Carboxy terminal region of haemolysin of Aeromonas sobria triggers dimerization
Carboxy terminal region of haemolysin of Aeromonas sobria triggers dimerization
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DOI：
10.1006/mpat.1999.0321
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发表时间：
2000-01-01
影响因子：
3.8
通讯作者：
Okamoto, K
中科院分区：
文献类型：
--
作者：
Nomura, T;Hamashima, H;Okamoto, K
温和气单胞菌的溶血素以溶血素原的形式释放到培养上清液中。在羧基末端去除42个氨基酸的肽将溶血素原转化为成熟溶血素。由于从成熟溶血素中去除的肽的作用尚未研究，我们突变溶血素基因，从羧基端删除几个氨基酸残基，在A. Sobria并分析产生的溶血素。删除三个以上的氨基酸残基显着降低了溶血素分泌到培养上清液的效率。缺失10个氨基酸的突变体溶血素在细胞中易于降解。此外，交联实验表明，溶血素在细胞中二聚化，因此二聚化的溶血素易位穿过外膜并出现在培养物上清液中。这些结果表明，溶血素原的羧基末端触发溶血素在细胞中的二聚化，导致溶血素有效分泌到培养上清液中。(C)北京大学出版社.
Haemolysin of Aeromonas sobria is released into the culture supernatant in the form of prohaemolysin. Removal of a 42 amino acid peptide at the carboxy-terminal end converts prohaemolysin into mature haemolysin. As the role of the peptide removed from the mature haemolysin has not been studied, we mutated the haemolysin genes to delete several amino acid residues from the carboxy terminus, expressed the mutant genes in A. sobria and analysed the haemolysins produced. Deletion of more than three amino acid residues significantly reduced the efficiency of secretion of haemolysin into the culture supernatant. Mutant haemolysins with deletion of 10 amino acids were easily degraded in cells. Furthermore, cross-linking experiments indicated that the haemolysins dimerize in cells, and thus dimerized haemolysins are translocated across the outer membrane and appear in the culture supernatant. These results indicated that the carboxy-terminal end of prohaemolysin triggers dimerization of haemolysin in cells, resulting in the efficient secretion of haemolysin into the culture supernatant. (C) 2000 Academic Press.