gene variant mutant D82G variant of GyrA A variant mutant in which aspartic acid in position 82 of the GyrA protein is replaced by tryptophan. It is resistant to 0.8 μg/ml of norfloxacin and causes elevated levels of gyrA and gyrB mRNA in vivo and lowers supercoiling activity of DNA gyrase in vitro in E. coli K12 strain MG1655 obtained from the ATCC. PMID: 15535862 colombos:gyrA_b2231.D82G_VARIANT D82G susbtitution in GyrA