East A K, Bhandari M, Hielm S, Collins M D
Department of Microbiology, Institute of Food Research, Earley Gate, Whiteknights Road, Reading RG6 6BZ, UK.
Curr Microbiol. 1998 Oct;37(4):262-8. doi: 10.1007/s002849900376.
Comparison of genes encoding type F botulinum neurotoxin progenitor complex in strains of proteolytic Clostridium botulinum strain Langeland, nonproteolytic Clostridium botulinum strain 202F, and Clostridium barati strain ATCC 43256 reveals an identical organization of genes encoding a protein of molecular mass of approx. 47 kDa (P-47), nontoxic-nonhemagglutinin (NTNH) and botulinum toxin (BoNT). Although homology between the protein components of the complexes encoded by these different species all producing botulinum neurotoxin type F is considerable (approx. 69-88% identity), exceptionally high homology is observed between the C-termini of the P-47s (approx. 96% identity) and the NTNHs (approx. 94% identity) encoded by Clostridium botulinum type F strain Langeland and Clostridium botulinum type A strain Kyoto. Such a region of extremely high sequence identity is strongly indicative of recombination in these strains synthesizing botulinum neurotoxins of different antigenic types.
对产蛋白解性肉毒梭菌Langeland菌株、非产蛋白解性肉毒梭菌202F菌株和巴氏梭菌ATCC 43256菌株中编码F型肉毒神经毒素前体复合物的基因进行比较，结果显示编码分子量约为47 kDa的蛋白质（P-47）、无毒非血凝素（NTNH）和肉毒毒素（BoNT）的基因具有相同的组织形式。尽管所有产生F型肉毒神经毒素的这些不同物种所编码的复合物的蛋白质成分之间的同源性相当高（约69 - 88%的同一性），但在F型肉毒梭菌Langeland菌株和A型肉毒梭菌京都菌株所编码的P-47的C末端（约96%的同一性）和NTNH（约94%的同一性）之间观察到异常高的同源性。这种极高序列同一性的区域强烈表明在这些合成不同抗原类型肉毒神经毒素的菌株中发生了重组。
