DETECTION OF VEROTOXIN-PRODUCING ESCHERICHIA-COLI O157-H7 BY MULTIPLEX POLYMERASE-CHAIN-REACTION

We constructed primers for multiplex polymerase chain reaction (PCR) t o detect verotoxin-producing Escherichia coli (VTEC) O157:H7, The mult iplex PCR primers were designed from the sequence of the flagellin str uctural gene of Escherichia coli flagellar type H7 (GenBank under acce ssion number L07388), and from the sequence of the rfbE gene of Escher ichia coli O157:H7 (GenBank under accession number S83460). In additio n to these primers, we used a primer pair reported by Karch and Meyer (J. Clin. Microbiol, 27: 2751-2757, 1989) to amplify various VT genes from VTEC, AII of the examined specimens (18 isolates) of VT-producing E. coli O157:H7 showed a positive result by the multiplex PCR test wi th the three sets of primers. The sensitivity of detection for VT-prod ucing E. coli O157:H7 was shown to be at least 3,000 cells per PCR tub e.