Zheng M, Wang X, Templeton L J, Smulski D R, LaRossa R A, Storz G
Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
J Bacteriol. 2001 Aug;183(15):4562-70. doi: 10.1128/JB.183.15.4562-4570.2001.
The genome-wide transcription profile of Escherichia coli cells treated with hydrogen peroxide was examined with a DNA microarray composed of 4,169 E. coli open reading frames. By measuring gene expression in isogenic wild-type and oxyR deletion strains, we confirmed that the peroxide response regulator OxyR activates most of the highly hydrogen peroxide-inducible genes. The DNA microarray measurements allowed the identification of several new OxyR-activated genes, including the hemH heme biosynthetic gene; the six-gene suf operon, which may participate in Fe-S cluster assembly or repair; and four genes of unknown function. We also identified several genes, including uxuA, encoding mannonate hydrolase, whose expression might be repressed by OxyR, since their expression was elevated in the DeltaoxyR mutant strain. In addition, the induction of some genes was found to be OxyR independent, indicating the existence of other peroxide sensors and regulators in E. coli. For example, the isc operon, which specifies Fe-S cluster formation and repair activities, was induced by hydrogen peroxide in strains lacking either OxyR or the superoxide response regulators SoxRS. These results expand our understanding of the oxidative stress response and raise interesting questions regarding the nature of other regulators that modulate gene expression in response to hydrogen peroxide.
利用一个由4169个大肠杆菌开放阅读框组成的DNA微阵列，检测了用过氧化氢处理的大肠杆菌细胞的全基因组转录谱。通过测量同基因野生型和oxyR缺失菌株中的基因表达，我们证实了过氧化物反应调节因子OxyR激活了大多数高度过氧化氢诱导型基因。DNA微阵列测量使得鉴定出几个新的OxyR激活基因成为可能，包括血红素生物合成基因hemH；可能参与铁硫簇组装或修复的六基因suf操纵子；以及四个功能未知的基因。我们还鉴定出几个基因，包括编码甘露糖酸水解酶的uxuA，其表达可能受到OxyR的抑制，因为它们在DeltaoxyR突变菌株中的表达升高。此外，发现一些基因的诱导是不依赖OxyR的，这表明大肠杆菌中存在其他过氧化物传感器和调节因子。例如，指定铁硫簇形成和修复活性的isc操纵子，在缺乏OxyR或超氧化物反应调节因子SoxRS的菌株中被过氧化氢诱导。这些结果扩展了我们对氧化应激反应的理解，并提出了关于其他调节因子性质的有趣问题，这些调节因子可调节基因表达以应对过氧化氢。
