title: Characterisation of Clostridium difficile strains by polymerase chain reaction with toxin A- and B-specific primers.
abstract: A total of 218 Clostridium difficile strains was examined for production of toxin A by ELISA, production of toxin B by a cytotoxin assay and the presence of toxin A and B gene-associated sequences by the polymerase chain reaction (PCR). After saturation amplification with toxin B-specific primers, the characteristic amplification product (591 bp) was detected in all 184 toxigenic strains examined. PCR with toxin A-specific primers gave positive results with all but one of the toxigenic strains. By contrast, PCR with toxin A- and toxin B-specific primers yielded negative results with all 34 non-toxigenic strains tested. This suggests that PCR detection of either the toxin A or B gene is a good indication of toxin production. PCR did not require DNA extraction or hybridisation and was convenient, sensitive and rapid. Toxigenic C. difficile could be detected in mixed cultures, suggesting a role for PCR in the identification of toxigenic C. difficile in primary culture.
authors.affiliation: Department of Medical Microbiology, St Bartholomew's Hospital Medical College, West Smithfield, London.
authors.forename: B W
authors.initials: BW
authors.lastname: Wren
authors.forename: S R
authors.initials: SR
authors.lastname: Heard
authors.forename: A I
authors.initials: AI
authors.lastname: al-Saleh
authors.forename: S
authors.initials: S
authors.lastname: Tabaqchali
mesh_terms: D001426:Bacterial Proteins; D001427:Bacterial Toxins / Q000096:biosynthesis*; D001483:Base Sequence; D016360:Clostridioides difficile / Q000302:isolation & purification / Q000378:metabolism*; D004277:DNA, Single-Stranded; D004768:Enterotoxins / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013045:Species Specificity
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004277:DNA, Single-Stranded; D004768:Enterotoxins; C041348:tcdA protein, Clostridium difficile; C031815:toxB protein, Clostridium difficile