Molecular and physiological characterisation of spore germination in Clostridium botulinum and C-sporogenes
Molecular and physiological characterisation of spore germination in Clostridium botulinum and C-sporogenes
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DOI：
10.1006/anae.2002.0424
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发表时间：
2002-06-01
期刊：
影响因子：
2.3
通讯作者：
Carlin, F
中科院分区：
文献类型：
--
作者：
Broussolle, V;Alberto, F;Carlin, F
萌发是休眠孢子发育成指数分裂细胞的第一步。在蛋白水解肉毒梭菌B型和C型中的孢子萌发。L-丙氨酸/L-乳酸盐/NaHCO 3对产孢菌的促生作用较强，L-丙氨酸/NaHCO 3的促生作用较弱，但肌苷或AGFK混合物（天冬酰胺、葡萄糖、果糖和钾离子）对产孢菌的促生作用不强。这表明在枯草芽孢杆菌中存在由gerA操纵子编码的L-丙氨酸受体的功能等价物，而响应肌苷（蜡状芽孢杆菌中的gerI）和AGFK混合物（B中的gerB/gerK）的萌发基因。枯草杆菌）似乎不存在。蛋白水解C. B型和C型肉毒杆菌。已经使用PCR用简并引物鉴定了产孢菌，并且显示出与编码GerAA和GerAB蛋白的gerAA和gerAB基因相似的遗传排列。在这两个物种中，第三个部分ORF可能编码GerAC同源物。GerAA和GerAB蛋白与其他梭菌属和芽孢杆菌属物种的GerAA和GerAB蛋白具有同源性，其中C.肉毒杆菌和C.产孢蛋白。这些物种的GerAA蛋白有6个假定的跨膜α-螺旋类似于其他L-丙氨酸依赖的萌发GerAA蛋白，表明膜位置。在C.肉毒杆菌的研究表明，gerAA和gerAB基因在孢子形成过程中共转录。(C)2002爱思唯尔科技有限公司版权所有
Germination is the first step in the development of dormant spores into exponentially dividing cells. Spore germination in proteolytic Clostridium botulinum type B and in C. sporogenes was triggered strongly by L-alanine/Llactate/NaHCO3, less well by L-alanine/NaHCO3, but not by inosine or the AGFK mixture (asparagine, glucose, fructose and potassium ions). This suggests the presence of a functional equivalent of the L-alanine receptor encoded by the gerA operon in Bacillus subtilis, while germination genes that respond to inosine (gerI in Bacillus cereus) and AGFK mixture (gerB/gerK in B. subtilis) appear to be absent. Putative gerA operons of proteolytic C. botulinum type B and C. sporogenes have been identified using PCR with degenerate primers and show a similar genetic arrangement with the gerAA and gerAB genes, encoding the GerAA and GerAB proteins. In both species, a third partial ORF may encode a GerAC homologue. The GerAA and GerAB proteins have homology with GerAA and GerAB proteins from other Clostridium and Bacillus species with the highest homology between the C. botulinum and C. sporogenes proteins. The GerAA proteins of these species have six putative transmembrane alpha-helices similar to other L-alanine-dependent germination GerAA proteins suggesting a membrane location. Expression studies in C. botulinum showed that the gerAA and gerAB genes are co-transcribed during sporulation. (C) 2002 Elsevier Science Ltd. All rights reserved