Genetic analysis of spontaneous resistance to ampicillin in Neisseria gonorrhoeae

Abstract

Step-wise intrinsic resistance to ampicillin in Neisseria gonorrhoeae was analyzed genetically by DNA-medi-ated transformation experiments. A first-step ampicillin-resistant (Amprl) mutant and a second-step ampicillinresistant (Ampr2) mutant generated during sequential selection were used in these studies.

Beta-lactamase plasmids and chromosomally mediated antibiotic resistance in pathogenic Neisseria species

“…For example, increasing resistance to penicillin can be achieved by the cooperative interaction of the penA, penB, mtr (multiple transformable resistance), and tem genes (68). A stepwise increase in resistance to ampicillin was observed through the combined effects of four amp alleles, ampA, ampB, ampC and ampD, none of which conferred resistance independently (36). Similarly, a combination of tet, penB, and mtr genes produces a 16-fold increase in tetracycline MICs (68).…”

Identification and enhancing production of a novel macrolide compound in engineeredStreptomyces peucetius

“…[36][37][38][39] The emergence and spread of antimicrobial resistance are serious problems for public health around the world; 40 for example, Streptococcus pneumoniae and Streptococcus pyogenes are resistant to erythromycin; 41 Staphylococcus aureus and Neisseria gonorrhoeae are resistant to penicillin. 42,43 Therefore, nding new bioactive compounds is an important strategy.…”

Beta-lactamase plasmids and chromosomally mediated antibiotic resistance in pathogenic Neisseria species.

“…For example, increasing resistance to penicillin can be achieved by the cooperative interaction of the penA, penB, mtr (multiple transformable resistance), and tem genes (68). A stepwise increase in resistance to ampicillin was observed through the combined effects of four amp alleles, ampA, ampB, ampC and ampD, none of which conferred resistance independently (36). Similarly, a combi-nation of tet, penB, and mtr genes produces a 16-fold increase in tetracycline MICs (68).…”