The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
Gene Review

gyrA  -  DNA gyrase subunit A

Escherichia coli O157:H7 str. EDL933

Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of gyrA

  • Some mutations in gyrA, known to confer high-level resistance to quinolones or CcdB, confer low-level resistance or hypersensitivity to albicidin in Escherichia coli [1].
  • In vivo selection of reduced enrofloxacin susceptibility in Ornithobacterium rhinotracheale and its resistance-related mutations in gyrA [2].
  • A nucleotide mutation associated with fluoroquinolone resistance observed in gyrA of in vitro obtained Rhodococcus equi mutants [3].
  • RESULTS: The Salmonella Infantis isolate exhibited the Asp87-->Tyr87 mutation in gyrA, but no resistance-mediating mutations in the other target genes [4].

High impact information on gyrA

  • In the Deltafis strain, both topA and gyrA/B genes were found to be upregulated [5].
  • We characterized gyrA and parC mutations and organic solvent tolerance (OST) [6].
  • With S. aureus, the dimer selected spontaneous resistant gyrA mutants, whereas ciprofloxacin selected a parC mutant [7].
  • Only three isolates (3%) were resistant to nalidixic acid (reduced susceptibility to ciprofloxacin), with a single mutation in the gyrA gene [8].
  • Typhimurium representative single-step mutants showed reduced susceptibilities associated with point mutations in the QRDR of the gyrA gene or efflux pump system [9].

Chemical compound and disease context of gyrA

  • OBJECTIVES: To evaluate the mutant prevention concentrations (MPCs) of ciprofloxacin for two susceptible and one first-step gyrA resistant mutant Escherichia coli strains in an in vitro kinetic model and to identify the pharmacodynamic index that best predicts prevention of resistance emergence [10].

Biological context of gyrA


Associations of gyrA with chemical compounds

  • The objective of this study was to analyse an array of ciprofloxacin and norfloxacin derivatives in order to determine those with good activity against bacteria that already present fluoroquinolone resistance associated with mutations in the gyrA and/or parC genes [12].

Other interactions of gyrA

  • In this study, the quinolone resistance-determining region (QRDR) in gyrA and gyrB of in vitro fluoroquinolone-resistant Rhodococcus equi mutants was sequenced [3].


  1. The Phytotoxin Albicidin is a Novel Inhibitor of DNA Gyrase. Hashimi, S.M., Wall, M.K., Smith, A.B., Maxwell, A., Birch, R.G. Antimicrob. Agents Chemother. (2007) [Pubmed]
  2. In vivo selection of reduced enrofloxacin susceptibility in Ornithobacterium rhinotracheale and its resistance-related mutations in gyrA. Marien, M., Decostere, A., Nauwynck, H., Froyman, R., Devriese, L., Haesebrouck, F. Microb. Drug Resist. (2006) [Pubmed]
  3. A nucleotide mutation associated with fluoroquinolone resistance observed in gyrA of in vitro obtained Rhodococcus equi mutants. Niwa, H., Hobo, S., Anzai, T. Vet. Microbiol. (2006) [Pubmed]
  4. Identification of the plasmid-borne quinolone resistance gene qnrS in Salmonella enterica serovar Infantis. Kehrenberg, C., Friederichs, S., de Jong, A., Michael, G.B., Schwarz, S. J. Antimicrob. Chemother. (2006) [Pubmed]
  5. Dynamic state of DNA topology is essential for genome condensation in bacteria. Ohniwa, R.L., Morikawa, K., Kim, J., Ohta, T., Ishihama, A., Wada, C., Takeyasu, K. EMBO J. (2006) [Pubmed]
  6. Phenotypic and genotypic characterization of fecal Escherichia coli isolates with decreased susceptibility to fluoroquinolones: results from a large hospital-based surveillance initiative. Lautenbach, E., Fishman, N.O., Metlay, J.P., Mao, X., Bilker, W.B., Tolomeo, P., Nachamkin, I. J. Infect. Dis. (2006) [Pubmed]
  7. Bactericidal activity and target preference of a piperazinyl-cross-linked ciprofloxacin dimer with Staphylococcus aureus and Escherichia coli. Zhao, X., Quinn, B., Kerns, R., Drlica, K. J. Antimicrob. Chemother. (2006) [Pubmed]
  8. Phenotypic and genotypic characterization of antimicrobial resistance in Escherichia coli O111 isolates. Guerra, B., Junker, E., Schroeter, A., Helmuth, R., Guth, B.E., Beutin, L. J. Antimicrob. Chemother. (2006) [Pubmed]
  9. Mutant prevention concentration of ciprofloxacin and enrofloxacin against Escherichia coli, Salmonella Typhimurium and Pseudomonas aeruginosa. Pasquali, F., Manfreda, G. Vet. Microbiol. (2007) [Pubmed]
  10. Selection of ciprofloxacin resistance in Escherichia coli in an in vitro kinetic model: relation between drug exposure and mutant prevention concentration. Olofsson, S.K., Marcusson, L.L., Komp Lindgren, P., Hughes, D., Cars, O. J. Antimicrob. Chemother. (2006) [Pubmed]
  11. Vertical transmission of a fluoroquinolone-resistant Escherichia coli within an integrated broiler operation. Petersen, A., Christensen, J.P., Kuhnert, P., Bisgaard, M., Olsen, J.E. Vet. Microbiol. (2006) [Pubmed]
  12. Antibacterial evaluation of a collection of norfloxacin and ciprofloxacin derivatives against multiresistant bacteria. Vila, J., Sánchez-Céspedes, J., Sierra, J.M., Piqueras, M., Nicolás, E., Freixas, J., Giralt, E. Int. J. Antimicrob. Agents (2006) [Pubmed]
WikiGenes - Universities