Ferrari F A, Trach K, LeCoq D, Spence J, Ferrari E, Hoch J A
Proc Natl Acad Sci U S A. 1985 May;82(9):2647-51. doi: 10.1073/pnas.82.9.2647.
The highly pleiotropic stage 0 sporulation locus of Bacillus subtilis, spo0A, has been cloned in bacteriophage lambda, subcloned in plasmids, and sequenced. The locus was found to code for a protein of 29,691 Da. Analysis of the in vivo transcripts from this region by nuclease S1 protection experiments located the start and stop of transcription of the locus. The transcription start site was preceded by a promoter resembling sigma 37-dependent promoters. Two mutations originally assigned to a second locus, spo0C, in this region because of their weakly pleiotropic phenotypes were cloned and sequenced. The mutations were found to be different missense alterations in the same base of the 10th codon preceding the carboxyl end of the Spo0A protein. These results, along with the finding that mutations in the spo0A gene product [Hoch, J. A., Trach, K., Kawamura, F. & Saito, H. (1985) J. Bacteriol. 161, 552-555] suppress the requirement for spo0B, spo0E, and spo0F gene products in transcription from sigma 28-dependent promoters, suggest that the Spo0A protein interacts directly with the transcription machinery to effect the initiation of sporulation. The deduced amino acid sequence of the Spo0A protein was highly related to that of the OmpR regulatory protein of Escherichia coli.
枯草芽孢杆菌高度多效性的0期芽孢形成基因座spo0A已被克隆到λ噬菌体中，亚克隆到质粒中并进行了测序。该基因座被发现编码一种29,691道尔顿的蛋白质。通过核酸酶S1保护实验对该区域的体内转录本进行分析，确定了该基因座转录的起始和终止位置。转录起始位点之前有一个类似于依赖σ37的启动子。最初由于其弱多效性表型而被指定为该区域第二个基因座spo0C的两个突变被克隆并测序。发现这些突变是Spo0A蛋白羧基末端之前第10个密码子同一碱基中的不同错义改变。这些结果，连同spo0A基因产物中的突变[霍赫，J. A.，特拉奇，K.，川村，F. & 斋藤，H.（1985年）《细菌学杂志》161，552 - 555]抑制了从依赖σ28的启动子转录时对spo0B、spo0E和spo0F基因产物的需求这一发现，表明Spo0A蛋白直接与转录机制相互作用以影响芽孢形成的起始。Spo0A蛋白推导的氨基酸序列与大肠杆菌的OmpR调节蛋白的序列高度相关。
