A PCR assay for discriminating Neisseria gonorrhoeaebeta-lactamase-producing plasmids

Oligonucleotide primers were developed for use in polymerase chain reaction (PCR) assays to differentiate three related, epidemic beta-lactamase-producing plasmids of Neisseria gonorrhoeae-the Asia-(7426 bp), Africa-(5599 bp) and Toronto-(5154 bp) type plasmids. One-hundred and two N. gonorrhoeae isolates with different plasmid profiles were tested-16 isolates carried the Asia plasmid, 41 isolates contained the Africa plasmid, 16 isolates contained the Toronto plasmid and 29 isolates contained no beta-lactamase-producing plasmids. Most (101/102) isolates also carried the gonococcal cryptic plasmid, while 27/102 and 44/102 isolates carried either the transfer plasmid or the tet M-containing plasmids, respectively. The assay was 100% sensitive and specific for identifying the correct plasmid type. This assay is useful for rapidly detecting the presence of gonococcal beta-lactamase-producing plasmids in clinical samples and discriminating them for epidemiological typing.