A DNA clone from Rhodococcus equi conferring low-level rifampin resistance through the ability to inactivate this antibiotic via its decomposition was identified. The iri (inactivation of rifampin) gene consisted of an open reading frame of 1,437 bp encoding a 479-amino-acid sequence strongly resembling those of monooxygenases acting upon phenolic compounds or involved in polyketide antibiotic synthesis. When expressed in Escherichia coli, the gene conferred resistance to a > 50-micrograms/ml concentration of the drug.
研究人员从马尾球菌中发现了一个 DNA 克隆,它能够通过分解
利福平使其失活,从而赋予马尾球菌低
水平的
利福平抗药性。iri(
利福平灭活)
基因由一个 1,437 bp 的开放阅读框组成,编码一个 479
氨基酸序列,该序列与作用于
酚类化合物或参与聚
酮类抗生素合成的单氧化酶非常相似。当该
基因在大肠杆菌中表达时,可产生对 50 微克/毫升浓度药物的抗药性。