Division of Global Epidemiology, Hokkaido University Research Center for Zoonosis Control, Sapporo, Japan.
Jpn J Infect Dis. 2012;65(1):72-4.
We conducted in vitro DNA supercoiling assays, utilizing recombinant DNA gyrases, to elucidate the influence of the lineage-specific serine or threonine residue at position 95 of GyrA on fluoroquinolone resistance in Mycobacterium tuberculosis. There was little effect of the GyrA-Ala74Ser amino acid substitution on activity of the GyrA-Ser95 gyrase, while activity of the GyrA-Asp94Gly-Ser95 gyrase was reduced. These findings were in striking contrast to previous reports analyzing GyrA with Thr95 and suggest an important impact of the amino acid in the development of fluoroquinolone resistance.
我们进行了体外 DNA 超螺旋化分析，利用重组 DNA 回旋酶，阐明分枝杆菌中 GyrA 位置 95 处的特异性丝氨酸或苏氨酸残基对氟喹诺酮耐药性的影响。GyrA-Ala74Ser 氨基酸取代对 GyrA-Ser95 回旋酶的活性影响很小，而 GyrA-Asp94Gly-Ser95 回旋酶的活性降低。这些发现与以前分析含有 Thr95 的 GyrA 的报告形成鲜明对比，表明该氨基酸对抗氟喹诺酮耐药性的发展有重要影响。
