Blanco M G, Hardisson C, Salas J A
J Gen Microbiol. 1984 Nov;130(11):2883-91. doi: 10.1099/00221287-130-11-2883.
Resistance to the endogenous antibiotic was studied in three actinomycetes that produce inhibitors of RNA polymerase. The three producers, Nocardia mediterranei (rifamycin producer), Streptomyces spectabilis (streptovaricin producer) and Streptomyces lydicus (streptolydigin producer), were each highly resistant to the antibiotic they produce (MIC greater than 200 micrograms ml-1) and in vivo RNA synthesis was also resistant. However, cross-resistance to the other RNA polymerase inhibitors was not found. Resistance to these antibiotics was due to target site modification, since the RNA polymerase enzymes of the three producing organisms were highly resistant in vitro to the corresponding antibiotic, and no antibiotic-inactivating enzymes were detected. A mutant was isolated from S. spectabilis which was sensitive to steptovaricin (its own product) and also showed an increased sensitivity to rifamycin and streptolydigin. This mutant had RNA polymerase which was extremely sensitive to the three antibiotics.
对三种产生RNA聚合酶抑制剂的放线菌的内源性抗生素抗性进行了研究。这三种产生菌，即地中海诺卡氏菌（利福霉素产生菌）、壮观链霉菌（链可变菌素产生菌）和里氏链霉菌（链霉溶菌素产生菌），各自对它们产生的抗生素具有高度抗性（最低抑菌浓度大于200微克/毫升），并且体内RNA合成也具有抗性。然而，未发现对其他RNA聚合酶抑制剂的交叉抗性。对这些抗生素的抗性是由于靶位点修饰，因为这三种产生菌的RNA聚合酶在体外对相应抗生素具有高度抗性，并且未检测到抗生素失活酶。从壮观链霉菌中分离出一个突变体，它对链可变菌素（其自身产物）敏感，并且对利福霉素和链霉溶菌素也表现出增加的敏感性。该突变体的RNA聚合酶对这三种抗生素极其敏感。
