Storz G, Tartaglia L A, Ames B N
Division of Biochemistry and Molecular Biology, University of California, Berkeley 94720.
Science. 1990 Apr 13;248(4952):189-94. doi: 10.1126/science.2183352.
The oxyR gene positively regulates genes induced by oxidative stress in Salmonella typhimurium and Escherichia coli. Purification of the OxyR protein showed that oxidized but not reduced OxyR activates transcription of oxidative stress-inducible genes in vitro. Conversion between the two forms of OxyR is rapid and reversible. Both the oxidized and the reduced forms of the OxyR protein are capable of binding to three diverse sequences upstream of OxyR-regulated promoters, but the interactions of the two forms of OxyR with the promoter regions are different. The results suggest that direct oxidation of the OxyR protein brings about a conformational change by which OxyR transduces an oxidative stress signal to RNA polymerase.
oxyR基因正向调控鼠伤寒沙门氏菌和大肠杆菌中由氧化应激诱导的基因。OxyR蛋白的纯化表明，氧化型而非还原型的OxyR在体外可激活氧化应激诱导基因的转录。两种形式的OxyR之间的转换快速且可逆。OxyR蛋白的氧化型和还原型均能够与OxyR调控启动子上游的三个不同序列结合，但两种形式的OxyR与启动子区域的相互作用有所不同。结果表明，OxyR蛋白的直接氧化导致构象变化，通过这种变化OxyR将氧化应激信号传递给RNA聚合酶。
