Šilar Radoslav, Holátko Jiří, Rucká Lenka, Rapoport Andrey, Dostálová Hana, Kadeřábková Pavla, Nešvera Jan, Pátek Miroslav
Institute of Microbiology, Czech Academy of Sciences, v.v.i., Vídeňská 1083, 142 20, Prague, Czech Republic.
Curr Microbiol. 2016 Sep;73(3):401-408. doi: 10.1007/s00284-016-1077-x. Epub 2016 Jun 6.
Promoter activities in Corynebacterium glutamicum strains with deletions of genes encoding sigma factors of RNA polymerase suggested that transcription from some promoters is controlled by two sigma factors. To prove that different sigma factors are involved in the recognition of selected Corynebacterium glutamicum promoters, in vitro transcription system was applied. It was found that a typical housekeeping promoter Pper interacts with the alternative sigma factor σ(B) in addition to the primary sigma factor σ(A). On the other way round, the σ(B)-dependent promoter of the pqo gene that is expressed mainly in the stationary growth phase was active also with σ(A). Some promoters of genes involved in stress responses (P1clgR, P2dnaK, and P2dnaJ2) were found to be recognized by two stress-responding sigma factors, σ(H) and σ(E). In vitro transcription system thus proved to be a useful direct technique for demonstrating the overlap of different sigma factors in recognition of individual promoters in C. glutamicum.
对谷氨酸棒杆菌中编码RNA聚合酶σ因子的基因进行缺失突变后，启动子活性研究表明，某些启动子的转录受两种σ因子控制。为证明不同的σ因子参与了谷氨酸棒杆菌特定启动子的识别过程，我们应用了体外转录系统。结果发现，典型的管家启动子Pper除了与主要的σ因子σ(A)相互作用外，还与替代σ因子σ(B)相互作用。另一方面，主要在稳定生长期表达的pqo基因的σ(B)依赖性启动子，与σ(A)结合时也具有活性。一些参与应激反应的基因启动子（P1clgR、P2dnaK和P2dnaJ2）被发现可被两种应激反应σ因子σ(H)和σ(E)识别。因此，体外转录系统被证明是一种有用的直接技术，可用于证明不同的σ因子在识别谷氨酸棒杆菌单个启动子时存在重叠现象。
