Drlica K, Franco R J, Steck T R
Department of Biology, University of Rochester, New York 14627.
J Bacteriol. 1988 Oct;170(10):4983-5. doi: 10.1128/jb.170.10.4983-4985.1988.
Two cases are described which indicate that RNA polymerase could alter DNA supercoiling. One occurred in a topA mutant in which abnormally high levels of plasmid supercoiling were lowered by rifampin, an inhibitor of the beta subunit of RNA polymerase. The second case involves suppression of a temperature-sensitive gyrB mutation by a rifampin-resistant allele of rpoB, the gene encoding the beta subunit of RNA polymerase. Measurements of chromosomal DNA supercoiling show that the rpoB mutation reduced DNA relaxation.
描述了两个案例，表明RNA聚合酶可改变DNA超螺旋。一个案例发生在topA突变体中，其中异常高水平的质粒超螺旋被利福平降低，利福平是RNA聚合酶β亚基的抑制剂。第二个案例涉及RNA聚合酶β亚基编码基因rpoB的利福平抗性等位基因对温度敏感的gyrB突变的抑制。染色体DNA超螺旋的测量表明，rpoB突变减少了DNA松弛。
