Intrinsic penicillin resistance in penicillinase-producing Neisseria gonorrhoeae strains

Microbiology and Immunology
F Ikeda

Abstract

The minimal inhibitory concentrations (MICs) of ampicillin for fifty strains of beta-lactamase-producing Neisseria gonorrhoeae (PPNG) isolated in Japan ranged from 1.56 to 200 micrograms/ml, and all the strains harbored a 4.5 megadalton plasmid. These strains were classified into two groups: dicloxacillin-susceptible (28%) and -resistant group (72%). A linear correlation was found in the dicloxacillin-susceptible strains between their beta-lactamase activity and the susceptibility to ampicillin, but not in the dicloxacillin-resistant strains. This suggests that the high ampicillin resistance in PPNG is due not only to acquiring the beta-lactamase producing plasmid, but also to some intrinsic resistance of the strains. To investigate a cause of the high ampicillin resistance, the beta-lactamase-producing plasmid, pTMS1, was transferred by conjugation to a penicillin-susceptible gonococcal strain as well as to its isogenic multiply antibiotic-resistant transformants, and the susceptibility of the transconjugants to ampicillin was determined. Acquisition of pTMS1 by a penicillin-susceptible strain resulted in a 32-fold increase in resistance to ampicillin, whereas the increase was 128-fold for its isogenic strains which contain so...Continue Reading

References

Sep 25, 1976·Lancet·W A AshfordV G Hemming
Dec 25, 1976·Lancet·A PercivalE H Annels
Apr 1, 1978·Antimicrobial Agents and Chemotherapy·S BergströmS Normark
Feb 1, 1979·Antimicrobial Agents and Chemotherapy·L A Eriquez, R F D'Amato
Jan 15, 1979·Biochemical and Biophysical Research Communications·T J DoughertyA Tomasz
Mar 11, 1977·Science·B I EisensteinP F Sparling
Apr 14, 1977·Nature·M Roberts, S Falkow
Mar 1, 1977·Antimicrobial Agents and Chemotherapy·L P ElwellS Falkow
Aug 1, 1977·Antimicrobial Agents and Chemotherapy·E S BaronJ A Wohlhieter
Apr 1, 1978·Journal of Bacteriology·T E SoxP F Sparling
Apr 8, 1976·Nature·C L HartleyM H Richmond
Mar 1, 1976·Journal of Bacteriology·G BiswasP F Sparling
Apr 1, 1972·Antimicrobial Agents and Chemotherapy·C H O'CallaghanA H Shingler
Dec 1, 1974·Journal of Bacteriology·F A SarubbiP F Sparling
Feb 1, 1972·Antimicrobial Agents and Chemotherapy·E B Lindström, K Nordström
Feb 1, 1973·The Journal of Infectious Diseases·P G Engelkirk, D E Schoenhard
Jan 1, 1968·Annual Review of Microbiology·E S Anderson
Nov 1, 1980·Antimicrobial Agents and Chemotherapy·T J DoughertyA Tomasz
Jun 1, 1963·Journal of Bacteriology·D S KELLOGGD I PIRKLE

❮ Previous
Next ❯

Related Concepts

Related Feeds

Antifungals

An antifungal, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis, cryptococcal meningitis, and others. Discover the latest research on antifungals here.

Antifungals (ASM)

An antifungal, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis, cryptococcal meningitis, and others. Discover the latest research on antifungals here.