1887

Abstract

SUMMERY:

Resistance of to structurally diverse hydrophobic agents (HAs) has been associated with missense or deletion mutations in the ( ultiple transferable esistance egulator) gene of laboratory-derived strains but their prevalence in clinical isolates was heretofore unknown. Since faecal lipids provide strong selective pressure for the emergence of variants resistant to HAs (HA), the nucleotide sequence of the gene from rectal isolates of , which displayed different levels of HA, was determined. Compared to the gene possessed by the HA-sensitive strain FA19, each clinical isolate contained mutations in the coding and/or promoter regions of their gene. A missense mutation in codon 45 (Gly-45 to Asp) was the most common mutation found in the strains studied and impacted the structure of the helix-turn-helix domain of the MtrR protein thought to be important in DNA-binding activity. Two clinical isolates bearing a missense mutation in codon 45 also contained a single basepair deletion in a 13 bp inverted sequence positioned within the promoter region. Introduction of sequences amplified from the clinical isolates into strain FA19 revealed that acquisition of the single basepair deletion was correlated with high level HA while mutations in the -coding region provided for an intermediate level of HA.

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1995-04-01
2022-01-24
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References

  1. Brow M. A. D., Pesin R., Sutcliffe J. G. 1985; The tetracycline repressor of pSCl0l. Mol Biol Evol 2:1–12
    [Google Scholar]
  2. Eisenstein B. I., Sparling P. F. 1978; Mutations to increased antibiotic sensitivity in naturally-occurring gonococci. Nature 271:242–244
    [Google Scholar]
  3. Hagman K. E., Pan W., Spratt B. G., Balthazar J. T., Judd R. C., Shafer W. M. 1995; Resistance of Neisseria gonorrhoeae to antimicrobial hydrophobic agents is modulated by the mtrCDE efflux system. Microbiology 141:611–622
    [Google Scholar]
  4. Klein J. R., Heinrich B., Plapp R. 1991; Molecular analysis and nucleotide sequence of the envCD operon of Escherichia coli . Mol & Gen Genet 230:230–240
    [Google Scholar]
  5. Ma D., Cook D. N., Alberti M., Pon N. G., Nikaido H., Hearst J. E. 1993; Molecular cloning and characterization of acrA and acrE genes of Escherichia coli . J Bacteriol 175:6299–6313
    [Google Scholar]
  6. Maness M. J., Sparling P. F. 1973; Multiple antibiotic resistance due to a single mutation in Neisseria gonorrhoeae . J Infect Dis 128:321–330
    [Google Scholar]
  7. McAllister C. F., Stephens D. S. 1993; Analysis in Neisseria meningitidis and other Neisseria species of genes homologous to the FKBP immunophilin family. Mol Microbiol 10:13–24
    [Google Scholar]
  8. McFarland L., Mietzner T. A., Knapp J. S., Sandstrom E., Holmes K. K., Morse S. A. 1983; Gonococcal sensitivity to fecal lipids can be mediated by an mtr-independent mechanism. J Clin Microbiol 18:121–127
    [Google Scholar]
  9. Morse S. A., Lysko P. G., McFarland L., Knapp J. S., Sandstrom E., Critchlow C., Holmes K. K. 1982; Gonococcal strains from homosexual men have outer membranes with reduced permeability to hydrophobic molecules. Infect Immun 37:432–438
    [Google Scholar]
  10. Pan W., Spratt B. G. 1994; Regulation of the permeability of the gonococcal cell envelope by the mtr system. Mol Microbiol 11:769–775
    [Google Scholar]
  11. Poole K., Heinrichs D. E., Neshat S. 1993a; Cloning and sequence analysis of an EnvCD homologue in Pseudomonas aeruginosa: regulation by iron and possible involvement in the secretion of siderophore pyoverdine. Mol Microbiol 10:529–544
    [Google Scholar]
  12. Poole K., Krebs K., McNally C., Neshat S. 1993b; Multiple antibiotic resistance in Pseudomonas aeruginosa: evidence for involvement of an efflux operon. J Bacteriol 175:7363–7372
    [Google Scholar]
  13. Sarubbi F. A., Sparling P. F., Blackman E., Lewis E. 1975; Loss of low-level antibiotic resistance in Neisseria gonorrhoeae due to env mutations. J Bacteriol 124:750–756
    [Google Scholar]
  14. Shafer W. M., Guymon L. F., Lind I., Sparling P. F. 1984; Identification of an envelope mutation (env-10) resulting in increased antibiotic susceptibility and pyocin resistance in a clinical isolate of Neisseria gonorrhoeae . Antimicrob Agents Chemother 25:767–769
    [Google Scholar]
  15. Sparling P. F., Sarubbi F. A., Blackman E. 1975; Inheritance of low-level resistance to penicillin, tetracycline, and chloramphenicol in Neisseria gonorrhoeae . J Bacteriol 124:740–749
    [Google Scholar]
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