Salaj-Smic E, Petranović D, Petranović M, Trgovcević Z
Mol Gen Genet. 1979;177(1):91-4. doi: 10.1007/BF00267257.
UV-inducible "SOS" processes associated with W reactivation of phage lambda were studied for their effect on repair of lambda prophage integrated in the bacterial chromosome. For this purpose, lambda c1857 ind red-lysogens were used. These lysogens, although non-inducible by UV light, can be induced by raising the temperature from 30 degrees to 42 degrees. If the W reactivation processes are involved in repair of the bacterial DNA, when the lysogens are incubated at 30 degrees after UV exposure W reactivation should be fully expressed and should also exert an effect on the bacterial chromosome and the prophage inside it. When heat-induction is delayed until the time at which W reactivation reaches its maximum, a considerable increase in phage survival might then be expected. The results presented in this report show, however, that the delayed induction had only a small effect on the survival of prophage in the wild-type strain (possibly attributable to excision repair) and no detectable effect on prophage in a uvrA strain. From these results we conclude that W reactivation is largely irrelevant to the repair of UV-damaged bacterial DNA.
研究了与噬菌体λ的W复活相关的紫外线诱导“SOS”过程对整合在细菌染色体中的λ原噬菌体修复的影响。为此，使用了λc1857 ind red溶原菌。这些溶原菌虽然不能被紫外线诱导，但可以通过将温度从30℃提高到42℃来诱导。如果W复活过程参与细菌DNA的修复，那么在紫外线照射后将溶原菌在30℃下培养时，W复活应该会充分表达，并且也应该对细菌染色体及其内部的原噬菌体产生影响。当热诱导延迟到W复活达到最大值的时间时，噬菌体存活率可能会显著增加。然而，本报告中的结果表明，延迟诱导对野生型菌株中原噬菌体的存活只有很小的影响（可能归因于切除修复），而对uvrA菌株中的原噬菌体没有可检测到的影响。从这些结果我们得出结论，W复活在很大程度上与紫外线损伤的细菌DNA的修复无关。
