Mutation in 23S rRNA associated with macrolide resistance in Neisseria gonorrhoeae.

ABSTRACT: Fifty-six azithromycin-resistant (MICs, 2.0 to 4.0 micro g/ml) Neisseria gonorrhoeae strains with cross-resistance to erythromycin (MICs, 2.0 to 64.0 micro g/ml), isolated in Canada between 1997 and 1999, were characterized, and their mechanisms of azithromycin resistance were determined. Most (58.9%) of them belonged to auxotype-serotype class NR/IB-03, with a 2.6-mDa plasmid. Based on resistance to crystal violet (MICs >or= 1 micro g/ml), 96.4% of these macrolide-resistant strains appeared to have increased efflux. Nine of the eleven strains selected for further characterization were found to have a promoter region mtrR mutation, a single-base-pair (A) deletion in the 13-bp inverted repeat, which is believed to cause overexpression of the mtrCDE-encoded efflux pump. The two remaining mac

SUBMITTER: Ng LK 

PROVIDER: S-EPMC127397 | biostudies-literature | 2002 Sep

REPOSITORIES: biostudies-literature