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Publication numberUS20070009947 A1
Publication typeApplication
Application numberUS 11/503,368
Publication dateJan 11, 2007
Filing dateAug 10, 2006
Priority dateSep 12, 1994
Also published asUS7943346, US20020055101, US20030180733, US20050042606, US20070105129, US20090053703
Publication number11503368, 503368, US 2007/0009947 A1, US 2007/009947 A1, US 20070009947 A1, US 20070009947A1, US 2007009947 A1, US 2007009947A1, US-A1-20070009947, US-A1-2007009947, US2007/0009947A1, US2007/009947A1, US20070009947 A1, US20070009947A1, US2007009947 A1, US2007009947A1
InventorsMichel Bergeron, Marc Ouellette, Paul Roy
Original AssigneeBergeron Michel G, Marc Ouellette, Roy Paul H
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Specific and universal probes and amplification primers to rapidly detect and identify common bacterial pathogens and antibiotic resistance genes from clinical specimens for routine diagnosis in microbiology laboratories
US 20070009947 A1
Abstract
The present invention relates to DNA-based methods for universal bacterial detection, for specific detection of the common bacterial pathogens Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Streptococcus pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Staphylococcus saprophyticus, Streptococcus pyogenes, Haemophilus influenzae and Moraxella catarrhalis as well as for specific detection of commonly encountered and clinically relevant bacterial antibiotic resistance genes directly from clinical specimens or, alternatively, from a bacterial colony. The above bacterial species can account for as much as 80% of bacterial pathogens isolated in routine microbiology laboratories. The core of this invention consists primarily of the DNA sequences from all species-specific genomic DNA fragments selected by hybridization from genomic libraries or, alternatively, selected from data banks as well as any oligonucleotide sequences derived from these sequences which can be used as probes or amplification primers for PCR or any other nucleic acid amplification methods. This invention also includes DNA sequences from the selected clinically relevant antibiotic resistance genes. With these methods, bacteria can be detected (universal primers and/or probes) and identified (species-specific primers and/or probes) directly from the clinical specimens or from an isolated bacterial colony. Bacteria are further evaluated for their putative susceptibility to antibiotics by resistance gene detection (antibiotic resistance gene specific primers and/or probes). Diagnostic kits for the detection of the presence, for the bacterial identification of the above-mentioned bacterial species and for the detection of antibiotic resistance genes are also claimed. These kits for the rapid (one hour or less) and accurate diagnosis of bacterial infections and antibiotic resistance will gradually replace conventional methods currently used in clinical microbiology laboratories for routine diagnosis. They should provide tools to clinicians to help prescribe promptly optimal treatments when necessary. Consequently, these tests should contribute to saving human lives, rationalizing treatment, reducing the development of antibiotic resistance and avoid unnecessary hospitalizations.
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Claims(15)
1. A method to detect and identify the presence of a at least three target bacterial species in a sample, from amongst a plurality of possible bacterial species comprising,
contacting the sample with a set of amplification primers comprising a plurality of different amplification primer pairs, wherein said plurality of primer pairs comprises a first, second and third primer pair directed against target DNA from a first, second and third target bacterial species, respectively, wherein
(i) said first, second and third primer pairs hybridize solely to target DNA of said first, second and third target bacterial species, respectively, and are ubiquitous to at least 80% to said first, second and third target bacterial species, respectively, and;
(ii) each of said first, second and third primer pairs is derived from a DNA fragment that also hybridizes solely to said first, second and third target bacterial species, respectively, and is ubiquitous to at least about 80% of said first, second and third target bacterial species, respectively;
(iii) the primers are all chosen to allow amplification, under a single amplification protocol,
allowing amplification to proceed under said single amplification protocol; and
detecting the presence or amount of amplified product(s) from said first, second and third primer pairs as an indication of the presence of the first, second, or third target bacterial species in the sample, respectively.
2. The method of claim 1, wherein at least one of said plurality of primer pairs has a ubiquity of less than 100% for DNA of one of said target bacterial species, and wherein said set of amplification primers further comprises at least one additional pair of amplification primers for said target bacterial species
3. The method of claim 1, further comprising
contacting said sample with at least one universal amplification primer, wherein said at least one universal primer is chosen to allow amplification under said single amplification protocol, and
allowing amplification to proceed under said single amplification protocol.
4. The method of claim 1, further comprising
contacting said sample with at least one antibiotic resistance gene amplification primer pair that hybridizes to a target antibiotic resistance gene, wherein said at least one antibiotic resistance gene primer pair is chosen to allow amplification under said single amplification protocol, and
allowing amplification to proceed under said single amplification protocol.
5. The method of claim 1, wherein at least one target bacterial species is selected from the group consisting of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Streptococcus pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Staphylococcus saprophyticus, Streptococcus pyogenes, Haemophilus influenzae, Moraxella catarrhalis and group A Streptococci bearing exotoxin A gene speA.
6. The method of claim 4, wherein said antibiotic resistance gene is selected from the group consisting of blatem, blarob, blashv, aadb, aacC1, aacC2, aacC3, aacA4, mecA, vanA, vanH, vanx, satA, aacA-aphD, vat, vga, msrA, sul, and int.
7. The method of claim 1, wherein said DNA fragment(s) is or are selected from:
SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7 and a complementary sequence thereof, for determining the presence or amount of Escherichia coli;
SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, and a complementary sequence thereof, for determining the presence or amount of Klebsiella pneumoniae;
SEQ ID NO: 16, SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 19, SEQ ID NO: 20 and a complementary sequence thereof, for determining the presence or amount of Pseudomonas aeruginosa;
SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15 and complementary sequence thereof, for determining the presence or amount of Proteus mirabilis;
SEQ ID NO: 30, SEQ ID NO: 31, SEQ ID NO: 34, SEQ ID NO: 35 and complementary sequence thereof, for determining the presence or amount of Streptococcus pneumoniae;
SEQ ID NO: 37 and a complementary sequence thereof, for determining the presence or amount of Staphylococcus aureus;
SEQ ID NO: 36 and a complementary sequence thereof, for determining the presence or amount of Staphylococcus epidermidis;
SEQ ID NO: 1, SEQ ID NO: 2 and a complementary sequence thereof, for determining the presence or amount of Enterococcus faecalis;
SEQ ID NO: 21, SEQ ID NO: 22, SEQ ID NO: 23, SEQ ID NO: 24, and a complementary sequence thereof, for determining the presence or amount of Staphylococcus saprophyticus;
SEQ ID NO: 33, and a complementary sequence thereof, for determining the presence or amount of a bacterial species bearing exotoxin A gene speA;
SEQ ID NO: 32 and a complementary sequence thereof, for determining the presence or amount of Streptococcus pyogenes;
SEQ ID NO: 25, SEQ ID NO: 26, SEQ ID NO: 27 and a complementary sequence thereof, for determining the presence or amount of Haemophilus influenzae, and
SEQ ID NO: 28, SEQ ID NO: 29 and a complementary sequence thereof, for determining the presence or amount of Moraxella catarrhalis.
8. The method of claim 1, further comprising performing said method directly on a sample obtained from human patients, animals, environment or food.
9. The method of claim 1, further comprising performing said method directly on a sample consisting of one or more bacterial colonies.
10. The method of claim 1, wherein said amplification step comprises a method selected from the group consisting of:
(a) polymerase chain reaction (PCR),
(b) ligase chain reaction,
(c) nucleic acid sequence-based amplification,
(d) self-sustained sequence replication,
(e) strand displacement amplification,
(f) branched DNA signal amplification,
(g) nested PCR, and
(h) multiplex PCR.
11. The method of claim 10, wherein said amplification step comprises PCR.
12. The method of claim 11, wherein said PCR comprises an annealing step of only one second at about 55° C. and a denaturation step of only one second at about 95° C. without any time specifically allocated to an elongation step.
13. The method of claim 1, wherein said amplification and detection comprises:
(a) contacting said sample with an aqueous solution comprising said first, second and third oligonucleotide primers pairs,
wherein each primer is at least twelve nucleotides in length,
wherein each primer pair comprises a first and a second oligonucleotide primer,
wherein said first primers of said first, second, and third primer pairs hybridize solely with one of the two complementary strands of said first, second, or third target bacterial species DNA, respectively, comprising of any one of said sequences for determining the presence or amount of said bacterial species, that contain a target sequence, and
wherein said second primer of said primer pairs hybridizes solely with the other strands of said target DNA of said first second, or third target bacterial species such that each primer pair can form an extension product which contains the target sequence as a template;
(b) synthesizing an extension product of each of said primers which extension product contains the target sequence, and amplifying said target sequence, if any, to a detectable level; and
(c) detecting the presence or amount of said amplified target sequence as an indication of the presence or amount of said target bacterial species in said test sample.
14. The method of claim 13, wherein step (c) further comprises hybridizing said amplified target sequence with a probe.
15. The method of claim 1, wherein said plurality of different amplification primer pairs comprises at least one amplification primer pair selected from the group consisting of:
SEQ ID NO: 112 and SEQ ID NO: 113,
SEQ ID NO: 118 and SEQ ID NO: 119, and
SEQ ID NO: 160 and SEQ ID NO: 119 for the detection of Moraxella catarrhalis;
SEQ ID NO: 83 and SEQ ID NO: 84, and
SEQ ID NO: 85 and SEQ ID NO: 86; for the detection of Pseudomonas aeruginosa;
SEQ ID NO: 145 and SEQ ID NO: 146, and
SEQ ID NO: 147 and SEQ ID NO: 148, for the detection of Staphylococcus epidermidis;
SEQ ID NO: 149 and SEQ ID NO: 150,
SEQ ID NO: 149 and SEQ ID NO: 151, and
SEQ ID NO: 152 and SEQ ID NO: 153, for the detection of Staphylococcus aureus;
SEQ ID NO: 78 and SEQ ID NO: 79,
SEQ ID NO: 156 and SEQ ID NO: 157, and
SEQ ID NO: 158 and SEQ ID NO: 159; for the detection of Streptococcus pneumoniae;
SEQ ID NO: 143 and SEQ ID NO: 144, for the detection of a bacterial species bearing exotoxin A gene speA,
SEQ ID NO: 141 and 142, for the detection of Streptococcus pyogenes,
SEQ ID NO: 38 and SEQ ID NO: 39, and
SEQ ID NO: 40 and SEQ ID NO: 41, for the detection of Enterococcus faecalis,
SEQ ID NO: 61 and SEQ ID NO: 62,
SEQ ID NO: 67 and SEQ ID NO: 68,
SEQ ID NO: 135 and SEQ ID NO: 136, and
SEQ ID NO: 137 and SEQ ID NO: 138, for the detection of Klebsiella pneumoniae;
SEQ ID NO: 74 and SEQ ID NO: 75, and
SEQ ID NO: 133 and SEQ ID NO: 134, for the detection of Proteus mirabilis;
SEQ ID NO: 98 and SEQ ID NO: 99, and
SEQ ID NO: 139 and SEQ ID NO: 140, for the detection of Staphylococcus saprophyticus; or
SEQ ID NO: 154 and SEQ ID NO: 155, for the detection of Haemophilus influenzae.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 10/121,120 to Bergeron et al., entitled “Specific and universal probes and amplification primers to rapidly detect and identify common bacterial pathogens and antibiotic resistance genes from clinical specimens for routine diagnosis in microbiology laboratories,” filed Apr. 11, 2002, which is a continuation of U.S. patent application Ser. No. 09/452,599, filed Dec. 1, 1999, now abandoned, which is a continuation of U.S. patent application Ser. No. 08/526,840, filed Sep. 11, 1995, now U.S. Pat. No. 6,001,564, which is a continuation-in-part of U.S. patent application Ser. No. 08/304,732, filed Sep. 12, 1994, now abandoned.

REFERENCE TO SEQUENCE LISTING, TABLE, OR COMPUTER PROGRAM LISTING

The present application is being filed along with duplicate copies of a CD-ROM marked “Copy 1” and “Copy 2” containing a Sequence Listing in electronic format. The duplicate copies of CD-ROM entitled The “Copy 1” and “Copy 2” each contains a file entitled GENOM.046CP1CC2.txt created on Aug. 10, 2006 which is 117,760 Bytes in size. The information on these duplicate CD-ROMs is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

Classical Identification of Bacteria

Bacteria are classically identified by their ability to utilize different substrates as a source of carbon and nitrogen through the use of biochemical tests such as the API20E™ system. Susceptibility testing of Gram negative bacilli has progressed to microdilution tests. Although the API and the microdilution systems are cost-effective, at least two days are required to obtain preliminary results due to the necessity of two successive overnight incubations to isolate and identify the bacteria from the specimen. Some faster detection methods with sophisticated and expensive apparatus have been developed. For example, the fastest identification system, the autoSCAN-Walk-Away system™ identifies both Gram negative and Gram positive from isolated bacterial colonies in 2 hours and susceptibility patterns to antibiotics in only 7 hours. However, this system has an unacceptable margin of error, especially with bacterial species other than Enterobacteriaceae (York et al., 1992. J. Clin. Microbiol. 30:2903-2910). Nevertheless, even this fastest method requires primary isolation of the bacteria as a pure culture, a process which takes at least 18 hours if there is a pure culture or 2 to 3 days if there is a mixed culture.

Urine Specimens

A large proportion (40-50%) of specimens received in routine diagnostic microbiology laboratories for bacterial identification are urine specimens (Pezzlo, 1988, Clin. Microbiol. Rev. 1:268-280). Urinary tract infections (UTI) are extremely common and affect up to 20% of women and account for extensive morbidity and increased mortality among hospitalized patients (Johnson and Stamm, 1989; Ann. Intern. Med. 111:906-917). UTI are usually of bacterial etiology and require antimicrobial therapy. The Gram negative bacillus Escherichia coli is by far the most prevalent urinary pathogen and accounts for 50 to 60% of UTI (Pezzlo, 1988, op. cit.). The prevalence for bacterial pathogens isolated from urine specimens observed recently at the “Centre Hospitalier de l'Universit Laval (CHUL)” is given in Tables 1 and 2.

Conventional pathogen identification in urine specimens. The search for pathogens in urine specimens is so preponderant in the routine microbiology laboratory that a myriad of tests have been developed. The gold standard is still the classical semi-quantitative plate culture method in which a calibrated loop of urine is streaked on plates and incubated for 18-24 hours. Colonies are then counted to determine the total number of colony forming units (CFU) per liter of urine. A bacterial UTI is normally associated with a bacterial count of .gtoreq.10.sup.7 CFU/L in urine. However, infections with less than 10.sup.7 CFU/L in urine are possible, particularly in patients with a high incidence of diseases or those catheterized (Stark and Maki, 1984, N. Engl. J. Med. 311:560-564). Importantly, close to 80% of urine specimens tested are considered negative (<10.sup.7 CFU/L; Table 3).

Accurate and rapid urine screening methods for bacterial pathogens would allow a faster identification of negative results and a more efficient clinical investigation of the patient. Several rapid identification methods (Uriscreen™, UTIscreen™, Flash Track™ DNA probes and others) were recently compared to slower standard biochemical methods which are based on culture of the bacterial pathogens. Although much faster, these rapid tests showed low sensitivities and specificities as well as a high number of false negative and false positive results (Koening et al., 1992. J. Clin. Microbiol. 30:342-345; Pezzlo et al., 1992. J. Clin. Microbiol. 30:640-684).

Urine specimens found positive by culture are further characterized using standard biochemical tests to identify the bacterial pathogen and are also tested for susceptibility to antibiotics.

Any Clinical Specimens

As with urine specimen which was used here as an example, our probes and amplification primers are also applicable to any other clinical specimens. The DNA-based tests proposed in this invention are superior to standard methods currently used for routine diagnosis in terms of rapidity and accuracy. While a high percentage of urine specimens are negative, in many other clinical specimens more than 95% of cultures are negative (Table 4). These data further support the use of universal probes to screen out the negative clinical specimens. Clinical specimens from organisms other than humans (e.g. other primates, mammals, farm animals or live stocks) may also be used.

Towards the Development of Rapid DNA-Based Diagnostic

A rapid diagnostic test should have a significant impact on the management of infections. For the identification of pathogens and antibiotic resistance genes in clinical samples, DNA probe and DNA amplification technologies offer several advantages over conventional methods. There is no need for subculturing, hence the organism can be detected directly in clinical samples thereby reducing the costs and time associated with isolation of pathogens. DNA-based technologies have proven to be extremely useful for specific applications in the clinical microbiology laboratory. For example, kits for the detection of fastidious organisms based on the use of hybridization probes or DNA amplification for the direct detection of pathogens in clinical specimens are commercially available (Persing et al, 1993. Diagnostic Molecular Microbiology: Principles and Applications, American Society for Microbiology, Washington, D.C.).

The present invention is an advantageous alternative to the conventional culture identification methods used in hospital clinical microbiology laboratories and in private clinics for routine diagnosis. Besides being much faster, DNA-based diagnostic tests are more accurate than standard biochemical tests presently used for diagnosis because the bacterial genotype (e.g. DNA level) is more stable than the bacterial phenotype (e.g. biochemical properties). The originality of this invention is that genomic DNA fragments (size of at least 100 base pairs) specific for 12 species of commonly encountered bacterial pathogens were selected from genomic libraries or from data banks. Amplification primers or oligonucleotide probes (both less than 100 nucleotides in length) which are both derived from the sequence of species-specific DNA fragments identified by hybridization from genomic libraries or from selected data bank sequences are used as a basis to develop diagnostic tests. Oligonucleotide primers and probes for the detection of commonly encountered and clinically important bacterial resistance genes are also included. For example, Annexes I and II present a list of suitable oligonucleotide probes and PCR primers which were all derived from the species-specific DNA fragments selected from genomic libraries or from data bank sequences. It is clear to the individual skilled in the art that oligonucleotide sequences appropriate for the specific detection of the above bacterial species other than those listed in Annexes 1 and 2 may be derived from the species-specific fragments or from the selected data bank sequences. For example, the oligonucleotides may be shorter or longer than the ones we have chosen and may be selected anywhere else in the identified species-specific sequences or selected data bank sequences. Alternatively, the oligonucleotides may be designed for use in amplification methods other than PCR. Consequently, the core of this invention is the identification of species-specific genomic DNA fragments from bacterial genomic DNA libraries and the selection of genomic DNA fragments from data bank sequences which are used as a source of species-specific and ubiquitous oligonucleotides. Although the selection of oligonucleotides suitable for diagnostic purposes from the sequence of the species-specific fragments or from the selected data bank sequences requires much effort it is quite possible for the individual skilled in the art to derive from our fragments or selected data bank sequences suitable oligonucleotides which are different from the ones we have selected and tested as examples (Annexes I and II).

Others have developed DNA-based tests for the detection and identification of some of the bacterial pathogens for which we have identified species-specific sequences (PCT patent application Serial No. WO 93/03186). However, their strategy was based on the amplification of the highly conserved 16S rRNA gene followed by hybridization with internal species-specific oligonucleotides. The strategy from this invention is much simpler and more rapid because it allows the direct amplification of species-specific targets using oligonucleotides derived from the species-specific bacterial genomic DNA fragments.

Since a high percentage of clinical specimens are negative, oligonucleotide primers and probes were selected from the highly conserved 16S or 23S rRNA genes to detect all bacterial pathogens possibly encountered in clinical specimens in order to determine whether a clinical specimen is infected or not. This strategy allows rapid screening out of the numerous negative clinical specimens submitted for bacteriological testing.

We are also developing other DNA-based tests, to be performed simultaneously with bacterial identification, to determine rapidly the putative bacterial susceptibility to antibiotics by targeting commonly encountered and clinically relevant bacterial resistance genes. Although the sequences from the selected antibiotic resistance genes are available and have been used to develop DNA-based tests for their detection (Ehrlich and Greenberg, 1994. PCR-based Diagnostics in Infectious Diseases, Blackwell Scientific Publications, Boston, Mass.; Persing et al, 1993. Diagnostic Molecular Microbiology: Principles and Applications, American Society for Microbiology, Washington, D.C.), our approch is innovative as it represents major improvements over current “gold standard” diagnostic methods based on culture of the bacteria because it allows the rapid identification of the presence of a specific bacterial pathogen and evaluation of its susceptibility to antibiotics directly from the clinical specimens within one hour.

We believe that the rapid and simple diagnostic tests not based on cultivation of the bacteria that we are developing will gradually replace the slow conventional bacterial identification methods presently used in hospital clinical microbiology laboratories and in private clinics. In our opinion, these rapid DNA-based diagnostic tests for severe and common bacterial pathogens and antibiotic resistance will (i) save lives by optimizing treatment, (ii) diminish antibiotic resistance by reducing the use of broad spectrum antibiotics and (iii) decrease overall health costs by preventing or shortening hospitalizations.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided sequence from genomic DNA fragments (size of at least 100 base pairs and all described in the sequence listing) selected either by hybridization from genomic libraries or from data banks and which are specific for the detection of commonly encountered bacterial pathogens (i.e. Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Streptococcus pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Staphylococcus saprophyticus, Streptococcus pyogenes, Haemophilus influenzae and Moraxella catarrhalis) in clinical specimens. These bacterial species are associated with approximately 90% of urinary tract infections and with a high percentage of other severe infections including septicemia, meningitis, pneumonia, intraabdominal infections, skin infections and many other severe respiratory tract infections. Overall, the above bacterial species may account for up to 80% of bacterial pathogens isolated in routine microbiology laboratories.

Synthetic oligonucleotides for hybridization (probes) or DNA amplification (primers) were derived from the above species-specific DNA fragments (ranging in sizes from 0.25 to 5.0 kilobase pairs (kbp)) or from selected data bank sequences (GenBank and EMBL). Bacterial species for which some of the oligonucleotide probes and amplification primers were derived from selected data bank sequences are Escherichia coli, Enterococcus faecalis, Streptococcus pyogenes and Pseudomonas aeruginosa. The person skilled in the art understands that the important innovation in this invention is the identification of the species-specific DNA fragments selected either from bacterial genomic libraries by hybridization or from data bank sequences. The selection of oligonucleotides from these fragments suitable for diagnostic purposes is also innovative. Specific and ubiquitous oligonucleotides different from the ones tested in the practice are considered as embodiments of the present invention.

The development of hybridization (with either fragment or oligonucleotide probes) or of DNA amplification protocols for the detection of pathogens from clinical specimens renders possible a very rapid bacterial identification. This will greatly reduce the time currently required for the identification of pathogens in the clinical laboratory since these technologies can be applied for bacterial detection and identification directly from clinical specimens with minimum pretreatment of any biological specimens to release bacterial DNA. In addition to being 100% specific, probes and amplification primers allow identification of the bacterial species directly from clinical specimens or, alternatively, from an isolated colony. DNA amplification assays have the added advantages of being faster and more sensitive than hybridization assays, since they allow rapid and exponential in vitro replication of the target segment of DNA from the bacterial genome. Universal probes and amplification primers selected from the 16S or 23S rRNA genes highly conserved among bacteria, which permit the detection of any bacterial pathogens, will serve as a procedure to screen out the numerous negative clinical specimens received in diagnostic laboratories. The use of oligonucleotide probes or primers complementary to characterized bacterial genes encoding resistance to antibiotics to identify commonly encountered and clinically important resistance genes is also under the scope of this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Development of Species-Specific DNA Probes

DNA fragment probes were developed for the following bacterial species: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Streptococcus pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Haemophilus influenzae and Moraxella catarrhalis. (For Enterococcus faecalis and Streptococcus pyogenes, oligonucleotide sequences were exclusively derived from selected data bank sequences). These species-specific fragments were selected from bacterial genomic libraries by hybridization to DNA from a variety of Gram positive and Gram negative bacterial species (Table 5).

The chromosomal DNA from each bacterial species for which probes were seeked was isolated using standard methods. DNA was digested with a frequently cutting restriction enzyme such as Sau3AI and then ligated into the bacterial plasmid vector pGEM3Zf (Promega) linearized by appropriate restriction endonuclease digestion. Recombinant plasmids were then used to transform competent E. coli strain DH5α thereby yielding a genomic library. The plasmid content of the transformed bacterial cells was analyzed using standard methods. DNA fragments of target bacteria ranging in size from 0.25 to 5.0 kilobase pairs (kbp) were cut out from the vector by digestion of the recombinant plasmid with various restriction endonucleases. The insert was separated from the vector by agarose gel electrophoresis and purified in low melting point agarose gels. Each of the purified fragments of bacterial genomic DNA was then used as a probe for specificity tests.

For each given species, the gel-purified restriction fragments of unknown coding potential were labeled with the radioactive nucleotide α32P(dATP) which was incorporated into the DNA fragment by the random priming labeling reaction. Non-radioactive modified nucleotides could also be incorporated into the DNA by this method to serve as a label.

Each DNA fragment probe (i.e. a segment of bacterial genomic DNA of at least 100 bp in length cut out from clones randomly selected from the genomic library) was then tested for its specificity by hybridization to DNAs from a variety of bacterial species (Table 5). The double-stranded labeled DNA probe was heat-denatured to yield labeled single-stranded DNA which could then hybridize to any single-stranded target DNA fixed onto a solid support or in solution. The target DNAs consisted of total cellular DNA from an array of bacterial species found in clinical samples (Table 5). Each target DNA was released from the bacterial cells and denatured by conventional methods and then irreversibly fixed onto a solid support (e.g. nylon or nitrocellulose membranes) or free in solution. The fixed single-stranded target DNAs were then hybridized with the single-stranded probe. Pre-hybridization, hybridization and post-hybridization conditions were as follows: (i) Pre-hybridization; in 1 M NaCl+10% dextran sulfate+1% SDS (sodium dodecyl sulfate)+1 .mu.g/ml salmon sperm DNA at 650.degree. C. for 15 min. (ii) Hybridization; in fresh pre-hybridization solution containing the labeled probe at 650.degree. C. overnight. (iii) Post-hybridization; washes twice in 3.times.SSC containing 1% SDS (1.times.SSC is 0.15M NaCl, 0.015M NaCitrate) and twice in 0.1.times.SSC containing 0.1% SDS; all washes were at 650.degree. C. for 15 min. Autoradiography of washed filters allowed the detection of selectively hybridized probes. Hybridization of the probe to a specific target DNA indicated a high degree of similarity between the nucleotide sequence of these two DNAs. Species-specific DNA fragments selected from various bacterial genomic libraries ranging in size from 0.25 to 5.0 kbp were isolated for 10 common bacterial pathogens (Table 6) based on hybridization to chromosomal DNAs from a variety of bacteria performed as described above. All of the bacterial species tested (66 species listed in Table 5) were likely to be pathogens associated with common infections or potential contaminants which can be isolated from clinical specimens. A DNA fragment probe was considered specific only when it hybridized solely to the pathogen from which it was isolated. DNA fragment probes found to be specific were subsequently tested for their ubiquity (i.e. ubiquitous probes recognized most isolates of the target species) by hybridization to bacterial DNAs from approximately 10 to 80 clinical isolates of the species of interest (Table 6). The DNAs were denatured, fixed onto nylon membranes and hybridized as described above.

Sequencing of the Species-Specific Fragment Probes

The nucleotide sequence of the totality or of a portion of the species-specific DNA fragments isolated (Table 6) was determined using the dideoxynucleotide termination sequencing method which was performed using Sequenase™ (USB Biochemicals) or T7 DNA polymerase (Pharmacia). These nucleotide sequences are shown in the sequence listing. Alternatively, sequences selected from data banks (GenBank and EMBL) were used as sources of oligonucleotides for diagnostic purposes for Escherichia coli, Enterococcus faecalis, Streptococcus pyogenes and Pseudomonas aeruginosa. For this strategy, an array of suitable oligonucleotide primers or probes derived from a variety of genomic DNA fragments (size of more than 100 bp) selected from data banks was tested for their specificity and ubiquity in PCR and hybridization assays as described later. It is important to note that the data bank sequences were selected based on their potential of being species-specific according to available sequence information. Only data bank sequences from which species-specific oligonucleotides could be derived are included in this invention.

Oligonucleotide probes and amplification primers derived from species-specific fragments selected from the genomic libraries or from data bank sequences were synthesized using an automated DNA synthesizer (Millipore). Prior to synthesis, all oligonucleotides (probes for hybridization and primers for DNA amplification) were evaluated for their suitability for hybridization or DNA amplification by polymerase chain reaction (PCR) by computer analysis using standard programs (e.g. Genetics Computer Group (GCG) and Oligo™ 4.0 (National Biosciences)). The potential suitability of the PCR primer pairs was also evaluated prior to the synthesis by verifying the absence of unwanted features such as long stretches of one nucleotide, a high proportion of G or C residues at the 3′ end and a 3′-terminal T residue (Persing et al, 1993. Diagnostic Molecular Microbiology: Principles and Applications, American Society for Microbiology, Washington, D.C.).

Hybridization with Oligonucleotide Probes

In hybridization experiments, oligonucleotides (size less than 100 nucleotides) have some advantages over DNA fragment probes for the detection of bacteria such as ease of preparation in large quantities, consistency in results from batch to batch and chemical stability. Briefly, for the hybridizations, oligonucleotides were 5′ end-labeled with the radionucleotide γ32P(ATP) using T4 polynucleotide kinase (Pharmacia). The unincorporated radionucleotide was removed by passing the labeled single-stranded oligonucleotide through a Sephadex G50 column. Alternatively, oligonucleotides were labeled with biotin, either enzymatically at their 3′ ends or incorporated directly during synthesis at their 5′ ends, or with digoxigenin. It will be appreciated by the person skilled in the art that labeling means other than the three above labels may be used.

The target DNA was denatured, fixed onto a solid support and hybridized as previously described for the DNA fragment probes. Conditions for pre-hybridization and hybridization were as described earlier. Post-hybridization washing conditions were as follows: twice in 3×SSC containing 1% SDS, twice in 2×SSC containing 1% SDS and twice in 1×SSC containing 1% SDS (all of these washes were at 65° C. for 15 min ), and a final wash in 0.1× SSC containing 1% SDS at 25° C. for 15 min. For probes labeled with radioactive labels the detection of hybrids was by autoradiography as described earlier. For non-radioactive labels detection may be calorimetric or by chemiluminescence.

The oligonucleotide probes may be derived from either strand of the duplex DNA. The probes may consist of the bases A, G, C, or T or analogs. The probes may be of any suitable length and may be selected anywhere within the species-specific genomic DNA fragments selected from the genomic libraries or from data bank sequences.

DNA Amplification

For DNA amplification by the widely used PCR (polymerase chain reaction) method, primer pairs were derived either from the sequenced species-specific DNA fragments or from data bank sequences or, alternatively, were shortened versions of oligonucleotide probes. Prior to synthesis, the potential primer pairs were analyzed by using the program oligo™ 4.0 (National Biosciences) to verify that they are likely candidates for PCR amplifications.

During DNA amplification by PCR, two oligonucleotide primers binding respectively to each strand of the denatured double-stranded target DNA from the bacterial genome are used to amplify exponentially in vitro the target DNA by successive thermal cycles allowing denaturation of the DNA, annealing of the primers and synthesis of new targets at each cycle (Persing et al, 1993. Diagnostic Molecular Microbiology: Principles and Applications, American Society for Microbiology, Washington, D.C.). Briefly, the PCR protocols were as follows. Clinical specimens or bacterial colonies were added directly to the 50 μL PCR reaction mixtures containing 50 mM KCl, 10 mM Tris-HCl pH 8.3, 2.5 mM MgCl2, 0.4 μM of each of the two primers, 200 μM of each of the four dNTPs and 1.25 Units of Taq DNA polymerase (Perkin Elmer). PCR reactions were then subjected to thermal cycling (3 min at 95° C. followed by 30 cycles of 1 second at 95° C. and 1 second at 55° C.) using a Perkin Elmer 480™ thermal cycler and subsequently analyzed by standard ethidium bromide-stained agarose gel electrophoresis. It is clear that other methods for the detection of specific amplification products, which may be faster and more practical for routine diagnosis, may be used. Such methods may be based on the detection of fluorescence after amplification (e.g. TaqMan™ system from Perkin Elmer or Amplisensor™ from Biotronics) or liquid hybridization with an oligonucleotide probe binding to internal sequences of the specific amplification product. These novel probes can be generated from our species-specific fragment probes. Methods based on the detection of fluorescence are particularly promising for utilization in routine diagnosis as they are, very rapid and quantitative and can be automated.

To assure PCR efficiency, glycerol or dimethyl sulfoxide (DMSO) or other related solvents, can be used to increase the sensitivity of the PCR and to overcome problems associated with the amplification of target with a high GC content or with strong secondary structures. The concentration ranges for glycerol and DMSO are 5-15% (v/v) and 3-10% (v.backslash.v), respectively. For the PCR reaction mixture, the concentration ranges for the amplification primers and the MgCl2 are 0.1-1.0 μM and 1.5-3.5 mM, respectively. Modifications of the standard PCR protocol using external and nested primers (i.e. nested PCR) or using more than one primer pair (i.e. multiplex PCR) may also be used (Persing et al, 1993. Diagnostic Molecular Microbiology: Principles and Applications, American Society for Microbiology, Washington, D.C.). For more details about the PCR protocols and amplicon detection methods see examples 7 and 8.

The person skilled in the art of DNA amplification knows the existence of other rapid amplification procedures such as ligase chain reaction (LCR), transcription-based amplification systems (TAS), self-sustained sequence replication (3SR), nucleic acid sequence-based amplification (NASBA), strand displacement amplification (SDA) and branched DNA (bDNA) (Persing et al, 1993. Diagnostic Molecular Microbiology: Principles and Applications, American Society for Microbiology, Washington, D.C.). The scope of this invention is not limited to the use of amplification by PCR, but rather includes the use of any rapid nucleic acid amplification methods or any other procedures which may be used to increase rapidity and sensitivity of the tests. Any oligonucleotides suitable for the amplification of nucleic acid by approaches other than PCR and derived from the species-specific fragments and from selected antibiotic resistance gene sequences included in this document are also under the scope of this invention.

Specificity and Ubiquity Tests for Oligonucleotide Probes and Primers

The specificity of oligonucleotide probes, derived either from the sequenced species-specific fragments or from data bank sequences, was tested by hybridization to DNAs from the array of bacterial species listed in Table 5 as previously described. Oligonucleotides found to be specific were subsequently tested for their ubiquity by hybridization to bacterial DNAs from approximately 80 isolates of the target species as described for fragment probes. Probes were considered ubiquitous when they hybridized specifically with the DNA from at least 80% of the isolates. Results for specificity and ubiquity tests with the oligonucleotide probes are summarized in Table 6. The specificity and ubiquity of the amplification primer pairs were tested directly from cultures (see example 7) of the same bacterial strains. For specificity and ubiquity tests, PCR assays were performed directly from bacterial colonies of approximately 80 isolates of the target species. Results are summarized in Table 7. All specific and ubiquitous oligonucleotide probes and amplification primers for each of the 12 bacterial species investigated are listed in Annexes I and II, respectively. Divergence in the sequenced DNA fragments can occur and, insofar as the divergence of these sequences or a part thereof does not affect the specificity of the probes or amplification primers, variant bacterial DNA is under the scope of this invention.

Universal Bacterial Detection

In the routine microbiology laboratory a high percentage of clinical specimens sent for bacterial identification is negative (Table 4). For example, over a 2 year period, around 80% of urine specimens received by the laboratory at the “Centre Hospitalier de l'Université Laval (CHUL)” were negative (i.e. <107 CFU/L) (Table 3). Testing clinical samples with universal probes or universal amplification primers to detect the presence of bacteria prior to specific identification and screen out the numerous negative specimens is thus useful as it saves costs and may rapidly orient the clinical management of the patients. Several oligonucleotides and amplification primers were therefore synthesized from highly conserved portions of bacterial 16S or 23S ribosomal RNA gene sequences available in data banks (Annexes III and IV). In hybridization tests, a pool of seven oligonucleotides (Annex I; Table 6) hybridized strongly to DNA from all bacterial species listed in Table 5. This pool of universal probes labeled with radionucleotides or with any other modified nucleotides is consequently very useful for detection of bacteria in urine samples with a sensitivity range of ≧107 CFU/L. These probes can also be applied for bacterial detection in other clinical samples.

Amplification primers also derived from the sequence of highly conserved ribosomal RNA genes were used as an alternative strategy for universal bacterial detection directly from clinical specimens (Annex IV; Table 7). The DNA amplification strategy was developed to increase the sensitivity and the rapidity of the test. This amplification test was ubiquitous since it specifically amplified DNA from 23 different bacterial species encountered in clinical specimens.

Well-conserved bacterial genes other than ribosomal RNA genes could also be good candidates for universal bacterial detection directly from clinical specimens. Such genes may be associated with processes essential for bacterial survival (e.g. protein synthesis, DNA synthesis, cell division or DNA repair) and could therefore be highly conserved during evolution. We are working on these candidate genes to develop new rapid tests for the universal detection of bacteria directly from clinical specimens.

Antibiotic Resistance Genes

Antimicrobial resistance complicates treatment and often leads to therapeutic failures. Furthermore, overuse of antibiotics inevitably leads to the emergence of bacterial resistance. Our goal is to provide the clinicians, within one hour, the needed information to prescribe optimal treatments. Besides the rapid identification of negative clinical specimens with DNA-based tests for universal bacterial detection and the identification of the presence of a specific pathogen in the positive specimens with DNA-based tests for specific bacterial detection, the clinicians also need timely information about the ability of the bacterial pathogen to resist antibiotic treatments. We feel that the most efficient strategy to evaluate rapidly bacterial resistance to antimicrobials is to detect directly from the clinical specimens the most common and important antibiotic resistance genes (i.e. DNA-based tests for the detection of antibiotic resitance genes). Since the sequence from the most important and common bacterial antibiotic resistance genes are available from data banks, our strategy is to use the sequence from a portion or from the entire gene to design specific oligonucleotides which will be used as a basis for the development of rapid DNA-based tests. The sequence from the bacterial antibiotic resistance genes selected on the basis of their clinical relevance (i.e. high incidence and importance) is given in the sequence listing. Table 8 summarizes some characteristics of the selected antibiotic resistance genes.

EXAMPLES

The following examples are intended to be illustrative of the various methods and compounds of the invention.

Example 1

Isolation and cloning of fragments. Genomic DNAs from Escherichia coli strain ATCC 25922, Klebsiella pneumoniae strain CK2, Pseudomonas aeruginosa strain ATCC 27853, Proteus mirabilis strain ATCC 35657, Streptococcus pneumoniae strain ATCC 27336, Staphylococcus aureus strain ATCC 25923, Staphylococcus epidermidis strain ATCC 12228, Staphylococcus saprophyticus strain ATCC 15305, Haemophilus influenzae reference strain Rd and Moraxella catarrhalis strain ATCC 53879 were prepared using standard procedures. It is understood that the bacterial genomic DNA may have been isolated from strains other than the ones mentioned above. (For Enterococcus faecalis and Streptococcus pyogenes oligonucleotide sequences were derived exclusively from data banks). Each DNA was digested with a restriction enzyme which frequently cuts DNA such as Sau3AI. The resulting DNA fragments were ligated into a plasmid vector (pGEM3Zf) to create recombinant plasmids and transformed into competent E. coli cells (DH5α). It is understood that the vectors and corresponding competent cells should not be limited to the ones herein above specifically examplified. The objective of obtaining recombinant plasmids and transformed cells is to provide an easily reproducible source of DNA fragments useful as probes. Therefore, insofar as the inserted fragments are specific and selective for the target bacterial DNA, any recombinant plasmids and corresponding transformed host cells are under the scope of this invention. The plasmid content of the transformed bacterial cells was analyzed using standard methods. DNA fragments from target bacteria ranging in size from 0.25 to 5.0 kbp were cut out from the vector by digestion of the recombinant plasmid with various restriction endonucleases. The insert was separated from the vector by agarose gel electrophoresis and purified in a low melting point agarose gel. Each of the purified fragments was then used for specificity tests.

Labeling of DNA fragment probes. The label used was α32P(dATP), a radioactive nucleotide which can be incorporated enzymatically into a double-stranded DNA molecule. The fragment of interest is first denatured by heating at 95° C. for 5 min, then a mixture of random primers is allowed to anneal to the strands of the fragments. These primers, once annealed, provide a starting point for synthesis of DNA. DNA polymerase, usually the Klenow fragment, is provided along with the four nucleotides, one of which is radioactive. When the reaction is terminated, the mixture of new DNA molecules is once again denatured to provide radioactive single-stranded DNA molecules (i.e. the probe). As mentioned earlier, other modified nucleotides may be used to label the probes.

Specificity and ubiquity tests for the DNA fragment probes. Species-specific DNA fragments ranging in size from 0.25 to 5.0 kbp were isolated for 10 common bacterial pathogens (Table 6) based on hybridization to chromosomal DNAs from a variety of bacteria. Samples of whole cell DNA for each bacterial strain listed in Table 5 were transferred onto a nylon membrane using a dot blot apparatus, washed and denatured before being irreversibly fixed. Hybridization conditions were as described earlier. A DNA fragment probe was considered specific only when it hybridized solely to the pathogen from which it was isolated. Labeled DNA fragments hybridizing specifically only to target bacterial species (i.e. specific) were then tested for their ubiquity by hybridization to DNAs from approximately 10 to 80 isolates of the species of interest as described earlier. The conditions for pre-hybridization, hybridization and post-hybridization washes were as described earlier. After autoradiography (or other detection means appropriate for the non-radioactive label used), the specificity of each individual probe can be determined. Each probe found to be specific (i.e. hybridizing only to the DNA from the bacterial species from which it was isolated) and ubiquitous (i.e. hybridizing to most isolates of the target species) was kept for further experimentations.

Example 2

Same as example 1 except that testing of the strains is by colony hybridization. The bacterial strains were inoculated onto a nylon membrane placed on nutrient agar. The membranes were incubated at 37° C. for two hours and then bacterial lysis and DNA denaturation were carried out according to standard procedures. DNA hybridization was performed as described earlier.

Example 3

Same as example 1 except that bacteria were detected directly from clinical samples. Any biological samples were loaded directly onto a dot blot apparatus and cells were lysed in situ for bacterial detection. Blood samples should be heparizined in order to avoid coagulation interfering with their convenient loading on a dot blot apparatus.

Example 4

Nucleotide sequencing of DNA fragments. The nucleotide sequence of the totality or a portion of each fragment found to be specific and ubiquitous (Example 1) was determined using the dideoxynucleotide termination sequencing method (Sanger et al., 1977, Proc. Natl. Acad. Sci. USA. 74:5463-5467). These DNA sequences are shown in the sequence listing. Oligonucleotide probes and amplification primers were selected from these nucleotide sequences, or alternatively, from selected data banks sequences and were then synthesized on an automated Biosearch synthesizer (Millipore™) using phosphoramidite chemistry.

Labeling of oliaonucleotides. Each oligonucleotide was 5′ end-labeled with γ32P-ATP by the T4 polynucleotide kinase (Pharmacia) as described earlier. The label could also be non-radioactive.

Specificity test for oligonucleotide probes. All labeled oligonucleotide probes were tested for their specificity by hybridization to DNAs from a variety of Gram positive and Gram negative bacterial species as described earlier. Species-specific probes were those hybridizing only to DNA from the bacterial species from which it was isolated. Oligonucleotide probes found to be specific were submitted to ubiquity tests as follows.

Ubiquity test for oligonucleotide probes. Specific oligonucleotide probes were then used in ubiquity tests with approximately 80 strains of the target species. Chromosomal DNAs from the isolates were transferred onto nylon membranes and hybridized with labeled oligonucleotide probes as described for specificity tests. The batteries of approximately 80 isolates constructed for each target species contain reference ATCC strains as well as a variety of clinical isolates obtained from various sources. Ubiquitous probes were those hybridizing to at least 80% of DNAs from the battery of clinical isolates of the target species. Examples of specific and ubiquitous oligonucleotide probes are listed in Annex I.

Example 5

Same as example 4 except that a pool of specific oligonucleotide probes is used for bacterial identification (i) to increase sensitivity and assure 100% ubiquity or (ii) to identify simultaneously more than one bacterial species. Bacterial identification could be done from isolated colonies or directly from clinical specimens

Example 6

PCR amplification. The technique of PCR was used to increase sensitivity and rapidity of the tests. The PCR primers used were often shorter derivatives of the extensive sets of oligonucleotides previously developed for hybridization assays (Table 6). The sets of primers were tested in PCR assays performed directly from a bacterial colony or from a bacterial suspension (see Example 7) to determine their specificity and ubiquity (Table 7). Examples of specific and ubiquitous PCR primer pairs are listed in annex II.

Specificity and ubiquity tests for amplification primers. The specificity of all selected PCR primer pairs was tested against the battery of Gram negative and Gram positive bacteria used to test the oligonucleotide probes (Table 5). Primer pairs found specific for each species were then tested for their ubiquity to ensure that each set of primers could amplify at least 80% of DNAs from a battery of approximately 80 isolates of the target species. The batteries of isolates constructed for each species contain reference ATCC strains and various clinical isolates representative of the clinical diversity for each species.

Standard precautions to avoid false positive PCR results should be taken. Methods to inactivate PCR amplification products such as the inactivation by uracil-N-glycosylase may be used to control PCR carryover.

Example 7

Amplification directly from a bacterial colony or suspension. PCR assays were performed either directly from a bacterial colony or from a bacterial suspension, the latter being adjusted to a standard McFarland 0.5 (corresponds to 1.5 .times.10.sup.8 bacteria/mL). In the case of direct amplification from a colony, a portion of the colony was transferred directly to a 50 μL PCR reaction mixture (containing 50 mM KCl, 10 mM Tris pH 8.3, 2.5 mM MgCl2, 0.4 μM of each of the two primers, 200 μM of each of the four dNTPs and 1.25 Unit of Taq DNA polymerase (Perkin Elmer)) using a plastic rod. For the bacterial suspension, 4 μL of the cell suspension was added to 46 μL of the same PCR reaction mixture. For both strategies, the reaction mixture was overlaid with 50 μL of mineral oil and PCR amplifications were carried out using an initial denaturation step of 3 min. at 95° C. followed by 30 cycles consisting of a 1 second denaturation step at 95° C. and of a 1 second annealing step at 55° C. in a Perkin Elmer 480™ thermal cycler. PCR amplification products were then analyzed by standard agarose gel (2%) electrophoresis. Amplification products were visualized in agarose gels containing 2.5 μg/mL of ethidium bromide under UV at 254 nm. The entire PCR assay can be completed in approximately one hour.

Alternatively, amplification from bacterial cultures was performed as described above but using a “hot start” protocol. In that case, an initial reaction mixture containing the target DNA, primers and dNTPs was heated at 85° C. prior to the addition of the other components of the PCR reaction mixture. The final concentration of all reagents was as described above. Subsequently, the PCR reactions were submitted to thermal cycling and analysis as described above.

Example 8

Amplification directly from clinical specimens. For amplification from urine specimens, 4 .mu.L of undiluted or diluted (1:10) urine was added directly to 46 μL of the above PCR reaction mixture and amplified as described earlier.

To improve bacterial cell lysis and eliminate the PCR inhibitory effects of clinical specimens, samples were routinely diluted in lysis buffer containing detergent(s). Subsequently, the lysate was added directly to the PCR reaction mixture. Heat treatments of the lysates, prior to DNA amplification, using the thermocycler or a microwave oven could also be performed to increase the efficiency of cell lysis.

Our strategy is to develop rapid and simple protocols to eliminate PCR inhibitory effects of clinical specimens and lyse bacterial cells to perform DNA amplification directly from a variety of biological samples. PCR has the advantage of being compatible with crude DNA preparations. For example, blood, cerebrospinal fluid and sera may be used directly in PCR assays after a brief heat treatment. We intend to use such rapid and simple strategies to develop fast protocols for DNA amplification from a variety of clinical specimens.

Example 9

Detection of antibiotic resistance genes. The presence of specific antibiotic resistance genes which are frequently encountered and clinically relevant is identified using the PCR amplification or hybridization protocols described in previous sections. Specific oligonucleotides used as a basis for the DNA-based tests are selected from the antibiotic resistance gene sequences. These tests can be performed either directly from clinical specimens or from a bacterial colony and should complement diagnostic tests for specific bacterial identification.

Example 10

Same as examples 7 and 8 except that assays were performed by multiplex PCR (i.e. using several pairs of primers in a single PCR reaction) to (i) reach an ubiquity of 100% for the specific target pathogen or (ii) to detect simultaneously several species of bacterial pathogens.

For example, the detection of Escherichia coli requires three pairs of PCR primers to assure a ubiquity of 100%. Therefore, a multiplex PCR assay (using the “hot-start” protocol (Example 7)) with those three primer pairs was developed. This strategy was also used for the other bacterial pathogens for which more than one primer pair was required to reach a ubiquity of 100%.

Multiplex PCR assays could also be used to (i) detect simultaneously several bacterial species or, alternatively, (ii) to simultaneously identify the bacterial pathogen and detect specific antibiotic resistance genes either directly from a clinical specimen or from a bacterial colony.

For these applications, amplicon detection methods should be adapted to differentiate the various amplicons produced. Standard agarose gel electrophoresis could be used because it discriminates the amplicons based on their sizes. Another useful strategy for this purpose would be detection using a variety of fluorochromes emitting at different wavelengths which are each coupled with a specific oligonucleotide linked to a fluorescence quencher which is degraded during amplification to release the fluorochrome (e.g. TaqMan™, Perkin Elmer).

Example 11

Detection of amplification Products. The person skilled in the art will appreciate that alternatives other than standard agarose gel electrophoresis (Example 7) may be used for the revelation of amplification products. Such methods may be based on the detection of fluorescence after amplification (e.g. Amplisensor™, Biotronics; TaqMan™) or other labels such as biotin (SHARP Signal™system, Digene Diagnostics). These methods are quantitative and easily automated. One of the amplification primers or an internal oligonucleotide probe specific to the amplicon(s) derived from the species-specific fragment probes is coupled with the fluorochrome or with any other label. Methods based on the detection of fluorescence are particularly suitable for diagnostic tests since they are rapid and flexible as fluorochromes emitting different wavelengths are available (Perkin Elmer).

Example 12

Species-specific, universal and antibiotic resistance gene amplification primers can be used in other rapid amplification procedures such as the ligase chain reaction (LCR), transcription-based amplification systems (TAS), self-sustained sequence replication (3SR), nucleic acid sequence-based amplification (NASBA), strand displacement amplification (SDA) and branched DNA (bDNA) or any other methods to increase the sensitivity of the test. Amplifications can be performed from an isolated bacterial colony or directly from clinical specimens. The scope of this invention is therefore not limited to the use of PCR but rather includes the use of any procedures to specifically identify bacterial DNA and which may be used to increase rapidity and sensitivity of the tests.

Example 13

A test kit would contain sets of probes specific for each bacterium as well as a set of universal probes. The kit is provided in the form of test components, consisting of the set of universal probes labeled with non-radioactive labels as well as labeled specific probes for the detection of each bacterium of interest in specific clinical samples. The kit will also include test reagents necessary to perform the pre-hybridization, hybridization, washing steps and hybrid detection. Finally, test components for the detection of known antibiotic resistance genes (or derivatives therefrom) will be included. Of course, the kit will include standard samples to be used as negative and positive controls for each hybridization test.

Components to be included in the kits will be adapted to each specimen type and to detect pathogens commonly encountered in that type of specimen. Reagents for the universal detection of bacteria will also be included. Based on the sites of infection, the following kits for the specific detection of pathogens may be developed:

A kit for the universal detection of bacterial pathogens from most clinical specimens which contains sets of probes specific for highly conserved regions of the bacterial genomes.

A kit for the detection of bacterial pathogens retrieved from urine samples, which contains eight specific test components (sets of probes for the detection of Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus saprophyticus, Staphylococcus aureus and Staphylococcus epidermidis).

A kit for the detection of respiratory pathogens which contains seven specific test components (sets of probes for detecting Streptococcus pneumoniae, Moraxella catarrhalis, Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Streptococcus pyogenes and Staphylococcus aureus).

A kit for the detection of pathogens retrieved from blood samples, which contains eleven specific test components (sets of probes for the detection of Streptococcus pneumoniae, Moraxella catarrhalis, Haemophilus influenzae, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, Streptococcus pyogenes and Staphylococcus epidermidis).

A kit for the detection of pathogens causing meningitis, which contains four specific test components (sets of probes for the detection of Haemophilus influenzae, Streptococcus pneumoniae, Escherichia coli and Pseudomonas aeruginosa).

A kit for the detection of clinically important antibiotic resistance genes which contains sets of probes for the specific detection of at least one of the 19 following genes associated with bacterial resistance: blatem, blarob, blashv, aadB, aacC1, aacC2, aacC3, aacA4, mecA, vanA, vanh, vanX, satA, aacA-aphD, vat, vga, msrA, sul and int.

Other kits adapted for the detection of pathogens from skin, abdominal wound or any other clinically relevant kits will be developed.

Example 14

Same as example 13 except that the test kits contain all reagents and controls to perform DNA amplification assays. Diagnostic kits will be adapted for amplification by PCR (or other amplification methods) performed directly either from clinical specimens or from a bacterial colony. Components required for universal bacterial detection, bacterial identification and antibiotic resistance genes detection will be included.

Amplification assays could be performed either in tubes or in microtitration plates having multiple wells. For assays in plates, the wells will be coated with the specific amplification primers and control DNAs and the detection of amplification products will be automated. Reagents and amplification primers for universal bacterial detection will be included in kits for tests performed directly from clinical specimens. Components required for bacterial identification and antibiotic resistance gene detection will be included in kits for testing directly from colonies as well as in kits for testing directly from clinical specimens.

The kits will be adapted for use with each type of specimen as described in example 13 for hybridization-based diagnostic kits.

Example 15

It is understood that the use of the probes and amplification primers described in this invention for bacterial detection and identification is not limited to clinical microbiology applications. In fact, we feel that other sectors could also benefit from these new technologies. For example, these tests could be used by industries for quality control of food, water, pharmaceutical products or other products requiring microbiological control. These tests could also be applied to detect and identify bacteria in biological samples from organisms other than humans (e.g. other primates, mammals, farm animals and live stocks). These diagnostic tools could also be very useful for research purposes including clinical trials and epidemiological studies.

TABLE 1
Distribution of urinary isolates from positive urine samples
(≧107 CFU/L) at the Centre Hospitalier de l'Université
Laval (CHUL) for the 1992-1994 period
% of isolates
November April July January
1992 1993 1993 1994
Organisms n = 267a n = 265 n = 238 n = 281
Escherichia coli 53.2 51.7 53.8 54.1
Enterococcus faecalis 13.8 12.4 11.7 11.4
Klebsiella pneumoniae 6.4 6.4 5.5 5.3
Staphylococcus epidermidis 7.1 7.9 3.0 6.4
Proteus mirabilis 2.6 3.4 3.8 2.5
Pseudomonas aeruginosa 3.7 3.0 5.0 2.9
Staphylococcus saprophyticus 3.0 1.9 5.4 1.4
Othersb 10.2 13.3 11.8 16.0

an = total number of isolates for the indicated month

bSee Table 2

TABLE 2
Distribution of uncommona urinary isolates from positive urine samples
(≧107 CFU/L) at the Centre Hospitalier de l'Université Laval
(CHUL) for the 1992-1994 period
% of isolates
November April July January
Organisms 1992 1993 1993 1994
Staphylococcus aureus 0.4 1.1 1.3 1.4
Staphylococcus spp. 2.2 4.9 1.7 6.0
Micrococcus spp. 0.0 0.0 0.4 0.7
Enterococcus faecium 0.4 0.4 1.3 1.4
Citrobacter spp. 1.4 0.8 0.4 0.7
Enterobacter spp. 1.5 1.1 1.3 1.4
Klebsiella oxytoca 1.1 1.5 2.5 1.8
Serratia spp. 0.8 0.0 0.5 0.0
Proteus spp. 0.4 0.4 0.0 1.1
Moganella and Providencia 0.4 0.8 0.4 0.0
Hafania alvei 0.8 0.0 0.0 0.0
NFBb (Stenotrophomonas, 0.0 0.4 1.3 1.1
Acinetobacter
Candida spp. 0.8 1.9 0.7 0.4

aUncommon urinary isolates are those identified as “Others” in Table 1.

bNFB: non-fermentative bacilli

TABLE 3
Distribution of positivea (bacterial count ≧107 CFU/L) and
negative samples (bacterial count ≦107 CFU/L) urine specimens
tested at the Centre Hospitalier de l'Université Laval (CHUL)
for the 1992-1994 period
Number of isolates
November 1992 April 1993 July 1993 January 1994
n = 267a n = 265 n = 238 n = 281
received 53.2 51.7 53.8 54.1
positive 13.8 12.4 11.7 11.4
negative 6.4 6.4 5.5 5.3

an = total number of isolates for the indicated month

TABLE 4
Distribution of positive and negative clinical specimens tested in the
Microbiology Laboratory of the CHUL
No. of % of % of
samples positive negative
Clinical Specimensa tested specimens specimens
Urine 17,981 19.4 80.6
Haemoclulture/marrow 10.010 6.9 93.1
Sputum 1,266 68.4 31.6
Superficial pus 1,136 72.3 27.7
Cerebrospinal fluid 553 1.0 99.0
Synovial fluid-articular 523 2.7 97.3
Bronch./Trach./Amyg/Throat 502 56.6 43.4
Deep pus 473 56.8 43.2
Ears 289 47.1 52.9
Pleural and pericardial fluid 132 1.0 99.0
Peritonial fluid 101 28.6 71.4

aSpecimens tested from February 1994 to January 1995

TABLE 5
Bacterial Species (66) used for testing the specificity of DNA fragment probes,
oligonucleotides probes and PCR primers
Number of Number of
Bacterial species strains Bacterial species strains
Gram negative: tested Gram positive: tested
Proteus mirabilis 5 Streptococcus pneumoniae 7
Klebsiella pneumoniae 5 Streptococcus salivarius 2
Pseudomonas aeruginosa 5 Streptococcus viridans 2
Escherichia coli 5 Streptococcus pyogenes 2
Moraxella catarrhalis 5 Staphylococcus aureus 2
Proteus vulgaris 2 Staphylococcus epidermidis 2
Morganella morganii 2 Staphylococcus saprophyticus 5
Enterobater cloacae 2 Micrococcus species 2
Providencia stuartii 1 Corynebacterium species 2
Providencia spp. 1 Streptococcus group B 2
Enterobacter agglomerans 2 Staphylococcus simulans 2
Providencia rettgeri 2 Staphylococcus ludgunesis 1
Neisseria mucosa 1 Staphylococcus capitis 2
Providencia alcalifaciens 1 Staphylococcus haemolyticus 2
Providencia rustigianii 1 Staphylococcus hominis 2
Burkholderia cepacia 2 Enterococcus faecalis 2
Enterobacter aerogenes 2 Enterococcus faecium 1
Stenotrophomonas maltophilia 2 Staphylococcus warneri 1
Pseudomonas fluorescens 1 Enterococcus durans 1
Comamonas acidovorans 2 Streptococcus bovis 1
Pseudomonas putida 2 Diphteriods 2
Haemophilus influenzae 5 Lactobacillus acidophilus 1
Haemophilus parainfluenzae 2
Bordetella pertussis 2
Haemophilus 2
parahaemolyticus
Haemophilus aegyptius 2
Kingella indologenes 1
Moraxella atlantae 1
Neisseria cavaie 1
Neisseria subflava 1
Moraxella urethralis 1
Shigella sonnei 1
Shigella flexneri 1
Klebsiella oxytoca 2
Serratia marcescens 2
Salmonella typhimurium 1
Yersinia enterocolitica 1
Acinetobacter calcoaceticus 1
Acinetobacter lwoffi 1
Haftnia alvei 2
Citrobacter diversus 1
Citrobacter freundii 1
Salmonella species 1

TABLE 6
Species-specific DNA fragment and oligonucleotide probes for hybridization
Number of fragment probes Number of oligonucleotide probes
Organisms Tested Specific Ubiquitous Synthesized Specific Ubiquitous
E. coli d 20 12  9f
E. coli 14 2 2e
K. pneumoniae d 15 1 1
K. pneumoniae 33 3 3 18 12  8
P. mirabilis d  3 3 2
P. mirabilis 14 3 3e 15 8 7
P. aeruginosa d 26 13  9
P. aeruginosa  6 2 2e  6 0 0
S. saprophyticus  7 4 4 20 9 7
H. influenzae d 16 2 2
H. influenzae  1 1 1 20 1 1
S. pneumoniae d  6 1 1
M. catarrhalis  2 2 2  9 8 8
S. epidermidis 62 1 1
S. aureus 30 1 1
Universal probesd  7 7g

aNo DNA fragment or oligonucleotide probes were tested for E. faecalis and S. pyogenes.

bSizes of DNA fragments range from 0.25 to 5.0 kbp

cA specific probe was considered ubiquitous when at least 80% of isolates of the target species (approximately 80 isolates) were recognized by each specific probe. When 2 or more probes are combined, 100% of the isolates are recognized.

dThese sequences were selected from data banks.

eUbiquity tested with approximately 10 isolates of the target species

fA majority of probes (8/9) do not discriminate E. coli and Shigella spp.

gUbiquity testes with a pool of the 7 probes detected all 66 bacterial species listed in Table 5.

TABLE 7
PCR amplification for bacterial pathogens commonly encountered in urine,
sputum, blood, cerebrospinal fluid and other specimens
Primer pair DNA amplification
#(SEQ ID Amplicon from
Organism NO:) size (bp) Ubiquityb coloniesc from specimensd
E. coli 1e (55-56) 107 75/80 + +
2e (46-47) 297 77/80 + +
3 (42-43) 102 78/80 + +
4 (131-132) 134 73/80 + +
1 + 2 + 3 + 4 80/80 + +
E. faecalis 1e (38-39) 200 71/80 + +
2e (40-41) 121 79/80 + +
1 + 2 80/80 + +
K. pneumoniae 1 (67-68) 198 76/80 + +
2 (61-62) 143 67/80 + +
3h (135-136) 148 78/80 + N.T.i
4 (137-138) 116 69/80 + N.T.
1 + 2 + 3 80/80 + N.T.
P. mirabilis 1 (74-75) 167 73/80 + N.T.
2 (133-134) 123 8080 + N.T.
P. aeruginosa 1e (83-84) 139 79/80 + N.T.
2e (85-86) 223 80/80 + N.T.
S. saprophyticus 1 (98-99) 126 79/80 + +
2 (139-140) 190 80/80 + N.T.
M. catarrhalis 1 (112-113) 157 79/80 + N.T.
2 (118-119) 118 80/80 + N.T.
3 (160-119) 137 80/80 + N.T.
H. influenzae 1e (154-155) 217 80/80 + N.T.
S. pneumoniae 1e (156-157) 134 80/80 + N.T.
2e (158-159) 197 74/80 + N.T.
3 (78-79) 175 67/80 + N.T.
S. epidermidis 1 (147-148) 175 80/80 + N.T.
2 (145-146) 125 80/80 + N.T.
S. aureus 1 (152-153) 108 80/80 + N.T.
2 (149-150) 151 80/80 + N.T.
3 (149-151) 176 80/80 + N.T.
S. pyogenes f 1e (141-142) 213 80/80 + N.T.
2e (143-144) 157 24/24 + N.T.
Universal 1e (126-127) 241 194/195g + N.T.

aAll primer pairs are specific in PCR assays since no amplification was observed with DNA from 66 different species of both Gram positive and Gram negative bacteria other than the species of interest.

bThe ubiquity was normally tested on 80 strains of the species of interest. All retained primer pairs amplified at least 90% of the isolates. When combinations of primers were used, a ubiquity of 100% was reached.

cFor all primer pairs and multiplex combinations, PCR amplifications directly performed from a bacterial colony were 100% species specific.

dPCR assays performed directly from urine specimens.

ePrimer pairs derived from data bank sequences. Primer pairs with no “e” are derived from our species-specific fragments.

fFor S. pyogenes, primer pair #1 is specific for Group A Streptococci (GAS). Primer pair #2 is specific for GAS-producing exotoxin A gene (SpeA).

gUbiquity tested on 195 isolates from 23 species representative of bacterial pathogens commonly encountered in clinical specimens.

hOptimizations are in progress to eliminate non-specific amplification observed with some bacterial species other than the target species.

iN.T.: not tested.

TABLE 8
Selected antibiotic resistance genes for diagnostic purposes
Genes Antibiotics Bacteriaa SEQ ID NO:
(blatem) TEM-1 β-lactams Enterobacteriaceae, 161
Pseudomonadaceae,
Haemophilus,
Neisseria
(blarob) ROB-1 β-lactams Haemophilus, 162
Pasteurella
(blashv) SHV-1 β-lactams Klebsiella and other 163
Enterobacteriaceae
aadB, aacC1, aacC2, Aminoglycosides Enterobacteriaceae, 164, 165, 166, 167,
aacC3, aacC4, aacA4 Pseudomonadaceae 168
mecA β-lactams Staphylococci 169
vanH, vanA, vanX Vancomycin Enterococci 170
satA Macrolides Enterococci 173
aacA-aphD Aminoglycosides Enterococci, 174
Staphylococci
vat Macrolides Staphylococci 175
vga Macrolides Staphylococci 176
msrA Erythromycin Staphylococci 177
Int and Sul β-lactams, trimethoprim Enterobacteriaceae 171, 172
conserved sequences aminoglycosides, Pseudomonadaecae
antiseptic,
chloramphenicol

aBacteria having high incidence for the specified antibiotic resistance genes. The presence in other bacteria is not excluded.

ANNEX I
Specific and ubiquitous
oligonucleotide probes for hybridization
Originating
DNA fragment
SEQ SEQ
ID ID Nucleotide
NO: Nucleotide Sequence NO: position
Bacterial species:
Escherichia coli
 44 5′-CAC CCG CTT GCG TGG CAA GCT  5a 213-237
GCC C
 45 5′-CGT TTG TGG ATT CCA GTT CCA  5a 489-513
TCC G
 48 5′-TGA AGC ACT GGC CGA AAT GCT  6a 759-783
GCG T
 49 5′-GAT GTA CAG GAT TCG TTG AAG  6a 898-922
GCT T
 50 5′-TAG CGA AGG CGT AGC AGA AAC  7a 1264-1288
TAA C
 51 5′-GCA ACC CGA ACT CAA CGC CGG  7a 1227-1251
ATT T
 52 5′-ATA CAC AAG GGT CGC ATC TGC  7a 1313-1337
GGC C
 53 5′-TGC GTA TGC ATT GCA GAC CTT  7a 111-136
GTG GC
 54 5′-GCT TTC ACT GGA TAT CGC GCT  7a 373-397
TGG G
Bacterial species:
Proteus mirabilis
 70b 5′-TGG TTC ACT GAC TTT GCG ATG 12 23-47
TTT C
 72 5′-TCG AGG ATG GCA TGC ACT AGA 12 53-77
AAA T
 72b 5′-CGC TGA TTA GGT TTC GCT AAA 12  80-109
ATC TTA TTA
 73 5′-TTG ATC CTC ATT TTA TTA ATC 12 174-203
ACA TGA CCA
 76 5′-CCG CCT TTA GCA TTA ATT GGT 13 246-275
GTT TAT AGT
 77 5′-CCT ATT GCA GAT ACC TTA AAT 13 291-320
GTC TTG GGC
 80b 5′-TTG AGT GAT GAT TTC ACT GAC 14 18-42
TCC C
 81 5′-GTG AGA CAG TGA TGG TGA GGA 15a 1185-1203
CAC A
 82 5′-TGG TTG TCA TGC TGT TTG TGT 15a 1224-1230
GAA AAT
Bacterial species:
Klebsiella pneumoniae
 57 5′-GTG GTG TCG TTC AGG GGT TTC  8 45-67
AC
 58 5′-GCG ATA TTC ACA CCC TAC GCA  9 161-185
GCC A
 59b 5′-GTC GAA AAT GCC GGA AGA GGT  9 203-228
ATA CG
 60b 5′-ACT GAG CTG CAG ACC GGT AAA  9 233-258
ACT CA
 63b 5′-CGT GAT GGA TAT TCT TAA CGA 10 250-275
AGG GC
 64b 5′-ACC AAA CTG TTG AGC CGC CTG 10 201-223
GA
 65 5′-GTG ATC GCC CCT CAT CTG CTA 10 77-99
CT
 66 5′-CGC CCT TCG TTA AGA ATA TCC 10 249-274
ATC AC
 69 5′-CAG GAA GAT GCT GCA CCG GTT 11a 296-320
GTT G
Bacterial species:
Pseudomonas aeruginosa
 87 5′-AAT GCG GCT GTA CCT CGG CGC 18a 2985-3009
TGG T
 88 5′-GGC GGA GGG CCA GTT GCA CCT 18a 2929-2953
GCC A
 89 5′-AGC CCT GCT CCT CGG CAG CCT 18a 2821-2845
CTG C
 90 5′-TGG CTT TTG CAA CCG CGT TCA 18a 1079-1103
GGT T
 91 5′-GCG CCC GCG AGG GCA TGC TTC 19a 705-729
GAT G
 92 5′-ACC TGG GCG CCA ACT ACA AGT 19a 668-692
TCT A
 93 5′-GGC TAC GCT GCC GGG CTG CAG 19a 505-529
GCC G
 94 5′-CCG ATC TAG ACC ATC GAG ATG 20a 1211-1235
GGC G
 95 5′-GAG CGC GGC TAT GTG TTC GTC 20a 2111-2135
GGC T
Bacterial species:
Streptococcus pneumoniae
120 5′-TCT GTG CTA GAG ACT GCC CCA 30 423-447
TTT C
121 5′-CGA TGT CTT GAT TGA GCA GGG 31a 1198-1222
TTA T
Bacterial species:
Staphylococcus saprophyticus
 96 5′-CGT TTT TAC CCT TAC CTT TTC GTA 21 45-73
CTA CC
 97b 5′-TCA GGC AGA GGT AGT ACG AAA AGG 21 53-82
TAA GGG
100 5′-CAC CAA GTT TGA CAC GTG AAG ATT 22  89-115
CAT
101b 5′-ATG AGT GAA GCG GAG TCA GAT TAT 23 105-134
GTG CAG
102 5′-CGC TCA TTA CGT ACA GTG ACA ATC 24 20-44
G
103 5′-CTG GTT AGC TTG ACT CTT AAC AAT 24 61-90
CTT GTC
104b 5′-GAC GCG ATT GTC ACT GTA CGT AAT 24 19-48
GAG CGA
Bacterial species:
Moraxella catarrhalis
108 5′-GCC CCA AAA CAA TGA AAC ATA 28  81-105
TGG T
109 5′-CTG CAG ATT TTG GAA TCA TAT 28 126-130
CGC C
110 5′-TGG TTT GAC CAG TAT TTA ACG 28 165-189
CCA T
111 5′-CAA CGG CAC CTG ATG TAC CTT 28 232-256
GTA C
114 5′-TTA CAA CCT GCA CCA CAA GTC 29  97-121
ATC A
115 5′-GTA CAA ACA AGC CGT CAG CGA 29 139-163
CTT A
116 5′-CAA TCT GCG TGT GTG CGT TCA 29 178-200
CT
117 5′-GCT ACT TTG TCA GCT TTA GCC 29 287312
ATT CA
Bacterial species:
Haemophilus influenzae
105b 5′-GCG TCA GAA AAA GTA GGC GAA 25 138-165
ATG AAA G
106b 5′-AGC GGC TCT ATC TTG TAA TGA 26a 770-794
CAC A
107b 5′-GAA ACG TGA ACT CCC CTC TAT 27a 5184-5208
ATA A
Universal probesc
122b 5′-ATC CCA CCT TAG GCG GCT GGC
TCC A
123 5′-ACG TCA AGT CAT CAT GGC CCT
TAC GAG TAG G
124b 5′-GTG TGA CGG GCG GTG TGT ACA
AGG C
125b 5′-GAG TTG CAG ACT CCA ATC CGG
ACT ACG A
128b 5′-CCC TAT ACA TCA CCT TGC GGT
TTA GCA GAG AG
129 5′-GGG GGG ACC ATC CTC CA GGC
TAA ATA C
130b 5′-CGT CCA CTT TCG TGT TTG CAG
AGT GCT GTG TT

asequence from data banks

bThese sequences are from the opposite DNA strand of the sequences given in the Sequence listing.

ANNEX II
Specific and ubiquitous
primers for DNA amplification
Originating
DNA fragment
SEQ SEQ
ID ID Nucleotide
NO: Nucleotide Sequence NO: position
Bacterial species:
Escherichia coli
 42 5′-GCT TTC CAG CGT CAT ATT G  4 177-195
 43b 5′-GAT CTC GAC AAA ATG GTG A  4 260-278
 46 5′-TCA CCC GCT TGC GTG GC  5a 212-228
 47b 5′-GGA ACT GGA ATC CAC AAA C  5a 490-508
 55 5′-GCA ACC CGA ACT CAA CGC C  7a 1227-1245
 56b 5′-GCA GAT GCG ACC CTT GTG T  7a 1315-1333
131 5′-CAG GAG TAC GGT GAT TTT TA  3 60-79
132b 5′-ATT TCT GGT TTG GTC ATA CA  3 174-193
Bacterial species:
Enterococcus faecalis
 38 5′-GCA ATA CAG GGA AAA ATG TC  1a 69-88
 39b 5′-CTT CAT CAA ACA ATT AAC TC  1a 249-268
 40 5′-GAA CAG AAG AAG CCA AAA AA  2a 569-588
 41b 5′-GCA ATC CCA AAT AAT ACG GT  2a 670-689
Bacterial species:
Kiebsiella pneumoniae
 61 5′-GAC AGT CAG TTC GTC AGC C  9 37-55
 62b 5′-CGT AGG GTG TGA ATA TCG C  9 161-179
 67 5′-TCG CCC CTC ATC TGC TAC T 10 81-99
 68b 5′-GAT CGT GAT GGA TAT TCT T 10 260-278
135 5′-GCA GCG TGG TGT CGT TCA  8 40-57
136b 5′-AGC TGG CAA CGG CTG GTC  8 170-187
137 5′-ATT CAC ACC CTA CGC AGC CA  9 166-185
138b 5′-ATC CGG CAG CAT CTC TTT GT  9 262-281
Bacterial species:
Proteus mirabilis
 74 5′-GAA ACA TCG CAA AGT CAG T 12 23-41
 75b 5′-ATA AAA TGA GGA TCA AGT TC 12 170-189
133 5′-CGG GAG TCA GTG AAA TCA TC 14 17-36
134b 5′-CTA AAA TCG CCA CAC CTC TT 14 120-139
Bacterial species:
Staphylococcus saprophyticus
 98 5′-CGT TTT TAC CCT TAC CTT TTC 21 45-70
GTA CT
 99b 5′-ATC GAT CAT CAC ATT CCA TTT 21 143-170
GTT TTT A
139 5′-CTG GTT AGC TTG ACT CTT AAC 24 61-85
AAT C
140b 5′-TCT TAA CGA TAG AAT GGA GCA 24  26-250
ACT G
Bacterial species:
Psuedomonas aeruginosa
 83 5′-CGA GCG GGT GGT GTT CAT C 16a 554-572
 84b 5′-CAA GTC GTG GTG GGA GGG A 16a 674-692
 85 5′-TCG CTG TTC ATC AAG ACC C 17a 1423-1441
 86b 5′-CCG AGA ACC AGA CTT CAT C 17a 1627-1645
Bacterial species:
Moraxella catarrhalis
112 5′-GGC ACC TGA TGT ACC TTG 28 235-252
113b 5′-AAC AGC TCA CAC GCA TT 28 375-391
118 5′-TGT TTT GAG CTT TTT ATT TTT 29 41-64
TGA
119b 5′-CGC TGA CGG CTT GTT TGT ACC 29 137-158
A
160 5′-GCT CAA ATC AGG GTC AGC 29 22-39
119b 5′-CGC TGA CGG CTT GTT TGT ACG 29 137-158
A
Bacterial species:
Staphylococcus epidermidis
145 5′-ATC AAA AAG TTG GCG AAC CTT 36 21-45
TTC A
146b 5′-CAA AAG AGC GTG GAG AAA AGT 36 121-145
ATC A
147 5′-TCT CTT TTA ATT TCA TCT TCA 36 448-477
ATT CCA TAG
148b 5′-AAA CAC AAT TAC AGT CTG GTT 36 593-622
ATC CAT ATC
Bacterial species:
Staphylococcus aureus
149b 5′-CTT CAT TTT ACG GTG ACT TCT 37 409-438
TAG AAG ATT
150 5′-TCA ACT GTA GCT TCT TTA TCC 37 288-317
ATA CGT TGA
149b 5′-CTT CAT TTT ACG GTG ACT TCT 37 409-438
TAG AAG ATT
151 5′-ATA TTT TAG CTT TTC AGT TTC 37 263-292
TAT ATC AAC
152 5′-AAT CTT TGT CGG TAC ACG ATA 37  5-34
TTC TTC ACG
153b 5′-CGT AAT GAG ATT TCA GTA GAT 37  83-112
AAT ACA ACA
Bacterial species:
Haemophilus influenzae
154 5′-TTT AAC GAT CCT TTT ACT CCT 27a 5074-5098
TTT G
155b 5′-ACT GCT GTT GTA AAG AGG TTA 27a 5266-5290
AAA T
Bacterial species:
Streptococcus pneumoniae
 78 5′-AGT AAA ATG AAA TAA GAA CAG 34 164-189
GAC AG
 79b 5′-AAA ACA GGA TAG GAG AAC GGG 34 314-338
AAA A
156 5′-ATT TGG TGA CGG GTG ACT TT 31a 1401-1420
157b 5′-GCT GAG GAT TTG TTC TTC TT 31a 1515-1534
158 5′-GAG CGG TTT CTA TGA TTG TA 35a 1342-1361
159b 5′-ATC TTT CCT TTC TTG TTC TT 35a 1519-1538
Bacterial species:
Steptococcus pyogenes
149 5′-TGA AAA TTC TTG TAA CAG GC 32a 286-305
142b 5′-GGC CAC CAG CTT GCC CAA TA 32a 479-498
143 5′-ATA TTT TCT TTA TGA GGG TG 33a 966-985
144b 5′-ATC CTT AAA TAA AGT TGC CA 33a 1103-1122
Universal primersc
126 5′-GGA GGA AGG TGG GGA TGA CG
127b 5′-ATG GTG TGA CGG GCG GTG TG

aSequence from data banks

bThese sequences are from the opposite DNA strand of the sequences given in the Sequence listing.

ANNEX III
Selection of Universal Probes by Alignment of the
Sequences of Bacterial 16S and 23S Ribosomal RNA
Genes
Reverse strand of TGGACGG AGCCGCCTA GGTGGGAT
SEQ ID NO:122
1251                                              1300
Streptococcus TGAGGTAACC TTTTGGAGCC AGCCGCCTAA GGTGGGATAG ATGANNGGGG
salivarius
Proteus vulgaris TAGCTTAACC TTCGGGAGGG CGCTTACCAC TTTGTGATTC ATGACTGGGG
Pseudomonas aeruginosa TAGTCTAACC GCAAGGGGGA CGGTTACCAC GGAGTGATTC ATGACTGGGG
Neiserria gonorrhoeae TAGGGTAACC GCAAGGAGTC CGCTTACCAC GGTATGCTTC ATGACTGGGG
Streptococcus lactis TTGCCTAACC GCAAGGAGGG CGCTTCCTAA GGTAAGACCG ATGACNNGGG
SEQ ID NO: 123 ACGTCAAGTC ATCATGGC CCTTACGAGT AGG
1251                                              1300
Haemophilus influenzae GGTNGGGATG ACGTCAAGTC ..ATCATGGC CCTTACGAGT AGGGCTACAC
Neiserria gonorrhoeae GGTGGGGATG ACGTCAAGTC ..CTCATGGC CCTTATGACC AGGGCTTCAC
Pseudomonas cepacia GGTNGGGATG ACGTCAAGTC ..CTCATGGC CCTTATGGGT AGGGCTTCAC
Serratia marcescens GGTGGGGATG ACGTCAAGTC ..CTCATGGC CCTTATGGGT AGGGCTTCAC
Escherichia coli GGTGGGGATG ACGTCAAGTC ..ATCATGGC CCTTACGACC AGGGCTACAC
Proteus vulgaris GGTGGGGATG ACGTTAAGTC GTATCATGGC CCTTACGAGT AGGGCTACAC
Pseudomonas aeruginosa GGTGGGGATG ACGTCAAGTC ..ATCATGGC CCTTACGGCN AGGGCTACAC
Clostridium pefringens GGTGGGGATG ACGTNNAATC ..ATCATGCC CNTTATGTGT AGGOCTACAC
Mycoplasma hominis GGTGGGGATG ACGTCAAATC ..ATCATGCC TCTTACGAGT GGGGCCACAC
Helicobacter pylori GGTGGGGACG ACGTCAAGTC ..ATCATGGC CCTTACGCCT AGGGCTACAC
Mycoplasma pneumoniae GGAAGGGATG ACGTCAAATC ..ATCATGCC CCTTATGTCT AGGGCTGCAA
Reverse of the probe
SEQ ID NO:124 GCCTTGTACA CACCGCCCGT CACAC
1451                                   1490
Escherichia coli ACGTTCCCGG GCCTTGTACA CACCGCCCGT CACACCATGG
Neiserria ghonorrhoeae ACGTTCCCNG NNCTTGTACA CACCGCCCGT CACACCATGG
Pseudomonas cepacia ACGTTCCCGG GTCTTGTACA CACNGCCCGT CACACCATGG
Serratia marcescens ACGTTCCCGG GCCTTGTACA CACCGCCCGT CACACCATGG
Proteus vulgaris ACGTTCCCGG GCCTTGTACA CACCGCCCGT CACACCATGG
Haemophilus influenzae ACGTTCCCGG GCNTTGTACA CACCGCCCGT CACACCATGG
Pseudomonas aeruginosa ACGTTCCCGG GCCTTGTACA CACCGCCCGT CACACCATGG
Clostridium pefringens ACGTTCCCNG GTCTTGTACA CACCGCNCGT CACACCATGG
Mycoplasma hominis ACGTTCTCGG GTCTTGTACA CACCGCCCGT CACACCATGA
Helicobacter pylori ACGTTCCCGG GTCTTGTACT CACCGCCCGT CACACCATGG
Mycoplasma pneumoniae ACGTTCTCGG GTCTTGTACA CACCGCCCGT CAAACTATGA
Reverse strand of TCG TAGTCCGGAT TGGAGTCTGC AACTC
SEQ ID NO: 125
1361                                   1400
Escherichia coli AAGTGCGTCG TAGTCCGGAT TGGAGTCTGC AACTCGACTC
Neiserria ghonorrhoeae AAACCGATCG TAGTCCGGAT TGCACTCTGC AACTCGAGTG
Pseudomonas cepacia AAACCGATCG TAGTCCGGAT TGCACTCTGC AACTCGAGTG
Serratia marcescens AAGTATGTCG TAGTCCGGAT TGGAGTCTGC AACTCGACTC
Proteus vulgaris AAGTCTGTCG TAGTCCGGAT TGGAGTCTGC AACTCGACTC
Haemophilus influenzae AAGTACGTCT AAGTCCGGAT TGGAGTCTGC AACTCGACTC
Pseudomonas aeruginosa AAACCGATCG TAGTCCGGAT CGCAGTCTGC AACTCGACTG
Clostridium pefringens AAACCAGTCT CAGTTCGGAT TGTAGGCTGA AACTCGCCTA
Mycoplasma hominis AAGCCGATCT CAGTTCGGAT TGGAGTCTGC AATTCGACTC
Heilcobacter pylori ACACC..TCT CAGTTCGGAT TGTAGGCTGC AACTCGCCTG
Mycoplasma pneumoniae AAGTTGGTCT CAGTTCGGAT TGAGGGCTGC AATTCGTCTT
Reverse strand of
SEQ ID NO: 128
481                                                530
Lactobacillus lactis AAACAVAGCT CTCTGCTAAA CCGCAAGGTG ATGTATAGGG GGTGACGCCT
Eschenichia coli AAACACAGCA CTGTGCAAAC ACGAAAGTGG ACGTATACGG TGTGACGCCT
Pseudomonas aeruginosa AAACACAGCA CTCTGCAAAC ACGAAAGTGG ACGTATAGGG TGTGACGCCT
Pseudomonas cepacia AAACACAGCA CTCTGCAAAC ACGAAAGTGG ACGTATAAGG TGTGACGCCT
Bacillus AAACACAGGT CTCTGCGAAG TCGTAAGGCG ACGTATAGGG GCTGACACCT
stearothermophilus
Micrococcus luteus AAACACAGGT CCATGCGAAG TCGTAAGACG ATGTATATGG ACTGACTCCT
SEQ ID NO: 129 GGGGGGACC ATCCTCCAAG GCTAAATAC
1991                                              2040
Escherichia coli TGTCTGAATG TGGGGGGACC ATCCTCCAAG GCTAAATACT CCTGACTGAC
Pseudomonas aeruginosa TGTCTGAACA TGGGGGGACC ATCCTCCAAG GCTAAATACT ACTGACTGAC
Pseudomonas cepacia TGTCTGAAGA TGGGGGGACC ATCCTCCAAG GCTAAATACT CGTGATCGAC
Lactobacillus lactis AGTTTGAATC GCCCAGGACC ATCTCCCAAC CCTAAATACT CCTTAGTGAC
Micrococcus luteus CGTGTGAATC TGCCAGGACC ACCTGGTAAG CCTGAATACT ACCTGTTGAC
Reverse strand of AACACAGCA CTCTGCAAAC ACGAAAGTGG ACG
SEQ ID NO: 130
1981                                              2030
Pseudomonas aeruginosa TGTTTATTAA AAACACAGCA CTCTGCAAAC ACGAAAGTGG ACGTATAGGG
Escherichia coli TGTTTATTAA AAACACAGCA CTGTGCAAAC ACGAAAGTGG ACGTATACGG
Bacillus TGTTTAATAA AAACACAGCA CTCTGCAAAC ACGAAAGTGG ACGTATAGGG
stearothermophilus
Lactobacilius lactis TGTTTATCAA AAACACAGCT CTCTGCTAAA CCACAAGGTG ATGTATAGGG
Micrococcus luteus TGTTTATCAA AAACACAGGT CCATGCGAAG TCGTAAGACG ATGTATATGG
SEQ ID NO: 126 GGAGGAA GGTGGGGATG ACG
Reverse strand of CA CACCGCCCGT CACACCAT
SEQ ID NO: 127
Escherichia coli ACTGGAGGAA GGTGGGGATG ACGTCAAGTC . . . GCCTTGTACA CACCGCCCGT CACACCATGG
Neiserria ghonorrhoeae GCCGGAGGAA GGTGGGGATG ACGTCAAGTC . . . NNCTTGTACA CACCGCCCGT CACACCATGG
Pseudomonas cepacia ACCGGAGGAA GGTNGGGATG ACGTCAAGTC . . . GTCTTGTACA CACNGCCCGT CACACCATGG
Serratia marcescens ACTGGAGGAA GGTGGGGATG ACGTCAAGTC . . . GCCTTGTACA CACCGCCCGT CACACCATGG
Proteus vulgaris ACCGGAGGAA GGTGGGGATG ACGTTAAGTC . . . GCCTTGTACA CACCGCCCGT CACACCATGG
Haemophilus influenzae ACTGGAGGAA GGTNGGGATG ACGTCAAGTC . . . GCNTTGTACA CACCGCCCGT CACACCATGG
Legionella pneumophila ACCGGAGGAA GGCGGGGATG ACGTCAAGTC . . . GCCTTGTACA CACCGCCCGT CACACCATGG
Pseudomonas aeruginosa ACCGGAGGAA GGTGGGGATG ACGTCAAGTC . . . GCCTTGTACA CACCGCCCGT CACACCATGG
Clostridium pefringens CCAGGAGGAA GGTGGGGATG ACGTNNAATC . . . GTCTTGTACA CACCGCNCGT CACACCATGA
Mycoplasma hominis CTGGGAGGAA GGTGGGGATG ACGTCAAATC . . . GTCTTGTACA CACCGCCCGT CACACCATGG
Helicobacter pylori GGAGGAGGAA GGTGGGGACG ACGTCAAGTC . . . GTCTTGTACT CACCGCCCGT CACACCATGG
Mycoplasma pneumoniae ATTGGAGGAA GGAAGGGATG ACGTCAAATC . . . GTCTTGTACA CACCGCCCGT CAAACTATGA

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7943346May 1, 2006May 17, 2011Geneohm Sciences Canada Inc.Probes and primers for detection of bacterial pathogens and antibiotic resistance genes
US8034588Jan 7, 2004Oct 11, 2011Geneohm Sciences Canada Inc.Species-specific, genus-specific and universal DNA probes and amplification primers to rapidly detect and identify common bacterial and fungal pathogens and associated antibiotic resistance genes from clinical specimens for diagnosis in microbiology laboratories
US8067207May 2, 2006Nov 29, 2011Geneohm Sciences Canada Inc.Species-specific, genus-specific and universal DNA probes and amplification primers to rapidly detect and identify common bacterial and fungal pathogens and associated antibiotic resistance genes from clinical specimens for diagnosis in microbiology laboratories
US8114601Sep 27, 2005Feb 14, 2012Geneohm Sciences Canada Inc.Highly conserved genes and their use to generate probes and primers for detection of microorganisms
US8182996Aug 21, 2007May 22, 2012Geneohm Sciences Canada Inc.Compositions and methods for detecting Klebsiella pneumoniae
US8426137Jul 5, 2011Apr 23, 2013Genohm Sciences Canada, Inc.Methods and probes for detecting a vancomycin resistance gene
Classifications
U.S. Classification435/6.12, 435/91.2, 435/6.15
International ClassificationC07K14/26, C07K14/31, C07K14/285, C07K14/21, C07K14/245, C07K14/195, C07K14/315, C12P19/34, C12Q1/68
Cooperative ClassificationC07K14/3156, C07K14/285, C07K14/31, C07K14/195, C12Q1/6895, C12Q1/689, C07K14/245, C07K14/315, C07K14/212, C07K14/26, C07K14/21
European ClassificationC12Q1/68M10F, C07K14/285, C07K14/21, C07K14/245, C07K14/315, C07K14/315B, C07K14/31, C07K14/26, C07K14/21B, C07K14/195, C12Q1/68M10B
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