Benov L, Fridovich I
Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA.
Arch Biochem Biophys. 1995 Sep 10;322(1):291-4. doi: 10.1006/abbi.1995.1465.
Superoxide appears to be a major cause of stationary-phase death and heat kill. In support of this conclusion are the following observations: (a) Stationary-phase death was apparent in the sodA sodB, but not in the superoxide dismutase (SOD)-competent parental strain; (b) Stationary phase death in the sodA sodB strain was dioxygen-dependent; (c) A manganic porphyrin, which catalyzes the dismutation of superoxide, protected the sodA sodB strain against stationary-phase death; (d) Heating the sodA sodB strain to 42 degrees C caused a loss of viability not seen with the SOD-competent parental strain and preventable by the manganic porphyrin. Exposure to aerobic conditions induced antibiotic resistance in the sodA sodB, but not in the parental strain and the manganic porphyrin prevented that induction. This again indicates its ability to substitute for SOD in Escherichia coli.
超氧化物似乎是稳定期死亡和热杀伤的主要原因。以下观察结果支持这一结论：(a) sodA sodB菌株出现稳定期死亡，而具有超氧化物歧化酶（SOD）活性的亲本菌株则未出现；(b) sodA sodB菌株的稳定期死亡依赖于双原子氧；(c) 一种催化超氧化物歧化的锰卟啉可保护sodA sodB菌株免于稳定期死亡；(d) 将sodA sodB菌株加热至42摄氏度会导致其活力丧失，而具有SOD活性的亲本菌株则不会出现这种情况，且锰卟啉可预防这种情况。暴露于有氧条件下会诱导sodA sodB菌株产生抗生素抗性，而亲本菌株则不会，并且锰卟啉可阻止这种诱导。这再次表明其在大肠杆菌中替代SOD的能力。
