title: Plasmid-mediated beta-lactamase production in Neisseria gonorrhoeae.
abstract: Several beta-lactamase-producing, penicillin-resistant strains of Neisseria gonorrhoeae were examined for R plasmids. Penicillin-resistant strains isolated from men returning from the Far East and their contacts contained a 4.4 x 10(6)-dalton plasmid in common. Transformation studies and the isolation of a spontaneous penicillin-susceptible segregant showed that the structural gene for beta-lactamase was part of the 4.4 x 10(6)-dalton plasmid. An additional penicillin-resistant gonococcal strain isolated in London was found to harbor a 3.2 x 10(6)-dalton R plasmid. Deoxyribonucleic acid (DNA)-DNA duplex studies revealed that the penicillin-resistant gonococcal isolates contained a significant portion (about 40%) of the transposable DNA sequence, TnA, which includes the beta-lactamase gene commonly found on R plasmids of the Enterobacteriaceae and Haemophilus influenzae.
mesh_terms: D004269:DNA, Bacterial / Q000032:analysis; D004352:Drug Resistance, Microbial; D004587:Electrophoresis, Agar Gel; D005111:Extrachromosomal Inheritance; D005796:Genes; D009344:Neisseria gonorrhoeae / Q000032:analysis / Q000201:enzymology*; D009693:Nucleic Acid Hybridization; D010403:Penicillin Resistance; D010405:Penicillinase / Q000096:biosynthesis*; D010957:Plasmids; D011815:R Factors
chemical_list: D004269:DNA, Bacterial; D010405:Penicillinase