title: Molecular epidemiology of antibiotic resistance plasmids of Haemophilus species and Neisseria gonorrhoeae.
abstract: Ampicillin resistance in Haemophilus influenzae and Neisseria gonorrhoeae is most commonly due to plasmid-mediated production of the TEM beta-lactamase. The H. influenzae plasmids may have evolved by insertion of various antibiotic resistance transposons into a phenotypically cryptic plasmid found in one of 699 isolates of H. influenzae examined. The small, nonconjugative, beta-lactamase-specifying plasmids of N. gonorrhoeae and Haemophilus species are highly related. Phenotypically cryptic plasmids found in several epidemiologically distinct isolates of Haemophilus parainfluenzae are highly related to the beta-lactamase plasmids but carry no transposon A (TnA) sequences. This evidence strongly favors the hypothesis that the beta-lactamase plasmids evolved by the insertion of TnA (possibly introduced from enteric bacteria) into cryptic plasmids resident in H. parainfluenzae.
mesh_terms: D003227:Conjugation, Genetic; D004251:DNA Transposable Elements; D004352:Drug Resistance, Microbial; D004812:Epidemiologic Methods; D006069:Gonorrhea / Q000453:epidemiology / Q000382:microbiology; D006190:Haemophilus / Q000235:genetics*; D006192:Haemophilus Infections / Q000453:epidemiology / Q000382:microbiology; D006801:Humans; D009344:Neisseria gonorrhoeae / Q000201:enzymology / Q000235:genetics*; D010405:Penicillinase / Q000235:genetics; D011815:R Factors; D013449:Sulfonamides / Q000494:pharmacology; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D004251:DNA Transposable Elements; D013449:Sulfonamides; D010405:Penicillinase; D001618:beta-Lactamases