Synapse
⌘+K
Synapse
PulseExploreClubsResearchersJournals
Instagram
HomeClubsExplore
September 1, 1989Antimicrobial Agents and ChemotherapyOpen Access

Cloning and expression of the norA gene for fluoroquinolone resistance in Staphylococcus aureus

View Full Paper
Ask AI
Bookmark
Share

Authors

KUKimiko UbukataTokyo Medical UniversityNIN Itoh-YamashitaTeikyo UniversityMKM KonnoTokyo Medical and Dental University

Discussion

Loading...

Member takes

Implication

Molecular cloning study demonstrates norA gene expression confers norfloxacin resistance in Staphylococcus aureus, indicating its critical role in bacterial fluoroquinolone tolerance.

Key Points

  • Identify, clone, and characterize the norA gene conferring fluoroquinolone resistance from chromosomal DNA of Staphylococcus aureus.
  • Cloned a 5.5-kb HindIII chromosomal DNA fragment from resistant S. aureus TK2566 into E. coli TG1 via plasmid pTUS1 and into S. aureus via plasmid pTUS20.
  • Evaluated antibiotic susceptibility by measuring minimum inhibitory concentrations (MIC) for norfloxacin, ofloxacin, and ciprofloxacin.
  • Mapped the minimal functional gene region using restriction digestion (KpnI-HaeIII) and DNA hybridization against susceptible S. aureus strains.
  • Expression of pTUS1 in E. coli increased the norfloxacin MIC from 0.1 to 3.13 µg/ml.
  • Recloning the fragment into S. aureus (pTUS20) restored parent-level norfloxacin resistance, with lower resistance observed for ofloxacin and ciprofloxacin.
  • Localized functional norfloxacin resistance to a 2.6- to 3.2-kb KpnI-HaeIII subregion that hybridized to DNA from fluoroquinolone-susceptible S. aureus.

Cite This Study

Ubukata et al. (1989) studied this question.

synapsesocial.com/papers/6a6f7ebd5d37378ac1dc8dadhttps://doi.org/10.1128/aac.33.9.1535
View Full Paper
Ask AI
Bookmark
Share

Also Consider

Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context:

  1. 1Clinical isolate of Citrobacter freundii highly resistant to new quinolones1988 · 38 citations
  2. 2Nalidixic acid resistance: A second genetic character involved in DNA gyrase activity1977 · 838 citations
  3. 3Genetic and physical organization of the cloned gyrA and gyrB genes of Bacillus subtilis1985 · 48 citations
  4. 4In Vitro Antibacterial Activity of AM-715, a New Nalidixic Acid Analog1980 · 221 citations
  5. 5Nucleotide sequence of the <i>pbpA</i> gene and characteristics of the deduced amino acid sequence of penicillin‐binding protein 2 of <i>Escherichia coli</i> K121986 · 67 citations