PDF(Pubmed)
Abstract：
A consensus-directed search for sigma(B) promoters was used to locate potential candidates for new sigma(B)-dependent genes in Bacillus subtilis. Screening of those candidates by oligonucleotide hybridizations with total RNA from exponentially growing or ethanol-stressed cells of the wild type as well as a sigB mutant revealed 22 genes that required sigma(B) for induction by ethanol. Although almost 50% of the proteins encoded by the newly discovered sigma(B)-dependent stress genes seem to be membrane localized, biochemical functions have so far not been defined for any of the gene products. Allocation of the genes to the sigma(B)-dependent stress regulon may indicate a potential function in the establishment of a multiple stress resistance. AldY and YhdF show similarities to NAD(P)-dependent dehydrogenases and YdbP to thioredoxins, supporting our suggestion that sigma(B)-dependent proteins may be involved in the maintenance of the intracellular redox balance after stress.
摘要：
对sigma（B）启动子的共有定向搜索用于在枯草芽孢杆菌中定位新的sigma（B）依赖性基因的潜在候选物。通过与野生型指数生长或乙醇胁迫的细胞以及sigB突变体的总RNA的寡核苷酸杂交来筛选那些候选物，揭示了22个需要sigma（B）进行乙醇诱导的基因。尽管新发现的sigma（B）依赖性应激基因编码的蛋白质中有近50％似乎位于膜中，到目前为止，还没有为任何基因产物定义生化功能。将基因分配到σ（B）依赖性胁迫调节子可能表明在建立多重胁迫抗性中的潜在功能。AldY和YhdF与NAD（P）依赖性脱氢酶和YdbP与硫氧还蛋白相似，支持我们的建议，即sigma（B）依赖性蛋白可能参与应激后细胞内氧化还原平衡的维持。
