Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands.
PLoS One. 2011;6(7):e21859. doi: 10.1371/journal.pone.0021859. Epub 2011 Jul 1.
The B. subtilis transcriptional factor ComK regulates a set of genes coding for DNA uptake from the environment and for its integration into the genome. In previous work we showed that Bacillus cereus expressing the B. subtilis ComK protein is able to take up DNA and integrate it into its own genome. To extend our knowledge on the effect of B. subtilis ComK overexpression in B. cereus we first determined which genes are significantly altered. Transcriptome analysis showed that only part of the competence gene cluster is significantly upregulated. Two ComK homologues can be identified in B. cereus that differ in their respective homologies to other ComK proteins. ComK1 is most similar, while ComK2 lacks the C-terminal region previously shown to be important for transcription activation by B. subtilis ComK. comK1 and comK2 overexpression and deletion studies using transcriptomics techniques showed that ComK1 enhances and ComK2 decreases expression of the comG operon, when B. subtilis ComK was overexpressed simultaneously.
枯草芽孢杆菌转录因子 ComK 调节一组基因，这些基因编码从环境中摄取 DNA 并将其整合到基因组中。在之前的工作中，我们表明表达枯草芽孢杆菌 ComK 蛋白的蜡状芽孢杆菌能够摄取 DNA 并将其整合到自己的基因组中。为了扩展我们对枯草芽孢杆菌 ComK 过表达对蜡状芽孢杆菌影响的认识，我们首先确定了哪些基因发生了显著改变。转录组分析表明，只有部分感受态基因簇被显著上调。在蜡状芽孢杆菌中可以识别出两种 ComK 同源物，它们与其他 ComK 蛋白的同源性不同。ComK1 最为相似，而 ComK2 缺乏先前证明对枯草芽孢杆菌 ComK 转录激活很重要的 C 末端区域。使用转录组学技术进行 comK1 和 comK2 的过表达和缺失研究表明，当同时过表达枯草芽孢杆菌 ComK 时，ComK1 增强了 comG 操纵子的表达，而 ComK2 则降低了其表达。
