Siranosian K J, Grossman A D
Department of Biology, Masschusetts Institute of Technology, Cambridge 02139.
J Bacteriol. 1994 Jun;176(12):3812-5. doi: 10.1128/jb.176.12.3812-3815.1994.
spo0A and spo0H are needed for the initiation of sporulation and for the development of genetic competence in Bacillus subtilis. Transcription of spo0A initiates from two promoters, Pv and Ps. Pv is active during vegetative growth and is recognized by RNA polymerase containing sigma A. Expression from Ps increases during sporulation and depends on sigma H, the spo0H gene product. A deletion mutation, spo0A delta Ps, that removes the promoter controlled by sigma H blocked sporulation but had no detectable effect on competence. These results indicate that expression of spo0A from Ps is necessary for sporulation and that the requirement for spo0H in competence development is not due to its role in expression of spo0A.
芽孢形成的起始以及枯草芽孢杆菌遗传感受态的发育需要spo0A和spo0H。spo0A的转录起始于两个启动子Pv和Ps。Pv在营养生长期间具有活性,可被含有σA的RNA聚合酶识别。Ps的表达在芽孢形成期间增加,并且依赖于spo0H基因产物σH。一个缺失由σH控制的启动子的缺失突变体spo0A delta Ps阻断了芽孢形成,但对感受态没有可检测到的影响。这些结果表明,来自Ps的spo0A表达对于芽孢形成是必需的,并且在感受态发育中对spo0H的需求并非由于其在spo0A表达中的作用。