Identification and classification of Campylobacter strains by using nonradioactive DNA probes

Abstract

Acetylaminofluorene-labeled genomic DNA probes were used for the identification and classification of Campylobacter strains. Relationships among 17 well-known strains of Campylobacter species and subspecies were studied by comparing acetylaminofluoreneor 32P-labeled probes. Results obtained with both methods were closely correlated and were in agreement with those already reported. In an identification experiment, hybridization with nonradioactive probes was performed on 60 strains isolated from stool samples after subculturing and quick DNA extraction; conventional biochemical tests were conducted in parallel. A good correlation was found between the results obtained by nonradioactive hybridization and by biochemical tests. Thus, the acetylaminofluorene-labeled genomic DNA probe method is an interesting alternative for laboratories without access to radioisotopes for the identification and classification of bacteria. Campylobacter species have emerged during the past 10 years as major pathogens in the human gastrointestinal tract (38). C. jejuni is a leading cause of intestinal infection.

Use of the insertion element IS6110 for DNA fingerprinting of Mycobacterium tuberculosis isolates presenting various profiles of drug susceptibility

“…After hybridization, the modified probe is detected by using antibodies, directed against guanosylacetylaminofluorene, and an immunoenzymatic technique. AAF-modified nucleic acids have been widely used for in situ [23,24], dot-blot [14,15,[25][26][27], Southern, colony and plaque hybridizations [15] as well as for the detection of PCR products [28]. The ability to label RNA and DNA, doublestranded as well as single-stranded nucleic acids, extends the applicability of the AAF method.…”

“…Probes prepared in this way can be detected at the pg level and are stable for at least two years. The hybridization test using AAF-labelled ge-296 nomic DNA probes was sensitive enough to enable the detection of as few as 105 Campylobacter cells [27]. In addition, AAF-labelled Escherichia coli 16S + 23S rRNA was used successfully as a probe for DNA fingerprinting in molecular epidemiology [29].…”

A RAPID PCR METHOD FOR DIRECT DETECTION of LOW NUMBERS of CAMPYLOBACTER JEJUNI1

“…A DNA probe specific for C. jejuni could potentially be used for reliable identification of this bacteria, which would aid in the diagnosis of the disease. Several DNA probes for C. jejuni have been developed that have various degrees of specificity (Chevrier et al 1989;Cudjoe et al 1991;Korolik et al 1988;Olive et al 1990;Tenover d al. 1990).…”

Campylobacter jejuni: Specific oligonucleotides and DNA probes for use in polymerase chain reaction-based diagnosis

“…Campylobacter jejuni appears to be one of the most frequently involved species in human infectious diarrheal disease: its prevalence equals that of other enteric pathogens and can be even more important than that of Salmonella (for reviews see [1][2][3][4]). C. jejuni is routinely detected mainly by bacteriological, biochemical or serological methods, and in research laboratories speciesspecific antibodies [5] and genomic probes [6][7][8][9][10] Correspondence to: J.-L Guesdon, Laboratoire de Pr6d6veloppement des Sondes, Institut Pasteur. 25, rue du Docteur Roux, 75724 Paris Cedex 15,France. were developed.…”