Mariappan Aruljothi, Makarewicz Oliwia, Chen Xiao-Hua, Borriss Rainer
Klinik für Innere Medizin II, Sektion Klinische Infektiologie and Center for Sepsis Control and Care, Universitätsklinikum Jena, Jena, Germany.
J Mol Microbiol Biotechnol. 2012;22(2):114-25. doi: 10.1159/000338804. Epub 2012 Jun 7.
The plant-growth-promoting-rhizobacteria Bacillus amyloliquefaciens FZB42 possess an enormous potential to synthesize a wide range of antimicrobial, antiviral and nematocidal compounds. One of them, the dipeptide antibiotic bacilysin, is synthesized by FZB42 during exponential growth. Here, we have demonstrated that bacilysin is positively regulated by the two-component response regulator DegU at the transcriptional level. In addition, ScoC (Hpr), a transition state regulator, negatively controlled expression of the bacA gene, which is the first gene within the bacilysin operon. Both DegU and ScoC were bound directly at the bacA promoter region. Furthermore, a monocistronic gene located in close vicinity of the bac operon and essential for bacilysin production, ywfH, was also regulated by DegU. Transcription of the bac operon and of the ywfH gene in B. amyloliquefaciens FZB42 was positively controlled by the DegU global regulator protein. The role of interactions within a ternary complex formed by the antagonistically acting regulators DegU and ScoC as well as the bacA promoter sequence remains to be elucidated.
促进植物生长的根际细菌解淀粉芽孢杆菌FZB42具有合成多种抗菌、抗病毒和杀线虫化合物的巨大潜力。其中之一，二肽抗生素杆菌溶素，是FZB42在指数生长期合成的。在此，我们证明了杆菌溶素在转录水平上受到双组分响应调节因子DegU的正调控。此外，过渡态调节因子ScoC（Hpr）负调控杆菌溶素操纵子中的第一个基因bacA的表达。DegU和ScoC都直接结合在bacA启动子区域。此外，位于bac操纵子附近且对杆菌溶素产生至关重要的单顺反子基因ywfH也受DegU调控。解淀粉芽孢杆菌FZB42中bac操纵子和ywfH基因的转录受全局调节蛋白DegU的正调控。由拮抗作用的调节因子DegU和ScoC以及bacA启动子序列形成的三元复合物内相互作用的作用仍有待阐明。
