Mostertz Jörg, Scharf Christian, Hecker Michael, Homuth Georg
Institut für Mikrobiologie und Molekularbiologie, Ernst-Moritz-Arndt-Universität Greifswald, D-17487 Greifswald, Germany.
Microbiology (Reading). 2004 Feb;150(Pt 2):497-512. doi: 10.1099/mic.0.26665-0.
The Gram-positive soil bacterium Bacillus subtilis responds to oxidative stress by the activation of different cellular defence mechanisms. These are composed of scavenging enzymes as well as protection and repair systems organized in highly sophisticated networks. In this study, the peroxide and the superoxide stress stimulons of B. subtilis were characterized by means of transcriptomics and proteomics. The results demonstrate that oxidative-stress-responsive genes can be classified into two groups. One group encompasses genes which show similar expression patterns in the presence of both reactive oxygen species. Examples are members of the PerR and the Fur regulon which were induced by peroxide and superoxide stress. Similarly, both kinds of stress stimulated the activation of the stringent response. The second group is composed of genes primarily responding to one stimulus, like the members of the SOS regulon which were particularly upregulated in the presence of peroxide, and many genes involved in sulfate assimilation and methionine biosynthesis which were only induced by superoxide. Several genes encoding proteins of unknown function could be assigned to one of these groups.
革兰氏阳性土壤细菌枯草芽孢杆菌通过激活不同的细胞防御机制来应对氧化应激。这些机制由清除酶以及组织成高度复杂网络的保护和修复系统组成。在本研究中，通过转录组学和蛋白质组学对枯草芽孢杆菌的过氧化物和超氧化物应激刺激子进行了表征。结果表明，氧化应激反应基因可分为两组。一组包括在两种活性氧存在下表现出相似表达模式的基因。例如，PerR和Fur调控子的成员在过氧化物和超氧化物应激下被诱导。同样，这两种应激都刺激了严格反应的激活。第二组由主要对一种刺激作出反应的基因组成，如SOS调控子的成员在过氧化物存在下特别上调，以及许多参与硫酸盐同化和甲硫氨酸生物合成的基因仅由超氧化物诱导。几个编码功能未知蛋白质的基因可以归为这些组中的一组。
