alpha-Hemolysin, gamma-hemolysin, and leukocidin from Staphylococcus aureus: distant in sequence but similar in structure.
alpha-Hemolysin, gamma-hemolysin, and leukocidin from Staphylococcus aureus: distant in sequence but similar in structure.
复制标题
金黄色葡萄球菌中的 α-溶血素、γ-溶血素和杀白细胞素：顺序较远，但结构相似。
作者：
E. Gouaux;M. Hobaugh;L. Song
来自金黄色葡萄球菌的α-溶血素在靶细胞表面上从水溶性单体物质组装成膜结合的七聚体，产生导致细胞死亡和裂解的充满水的通道。金黄色葡萄球菌还产生γ-溶血素和杀白细胞素毒素，其作为两种组分毒素在红细胞和白细胞的破坏和溶解中起作用。在α-溶血素七聚体结构的背景下，α-溶血素、γ-溶血素和杀白细胞素的比对序列的分析支持以下结论：即使α-溶血素与γ-溶血素和杀白细胞素毒素之间的序列同一性水平处于所谓的模糊区，但原聚体的三维结构可能是保守的。与α-溶血素类似，γ-溶血素和杀白细胞素也可以形成寡聚跨膜通道，其中反平行的β-桶构成主要的膜嵌入结构域。
alpha-Hemolysin from Staphylococcus aureus assembles from a water-soluble, monomeric species to a membrane-bound heptamer on the surface of target cells, creating water-filled channels that lead to cell death and lysis. Staphylococcus aureus also produces the gamma-hemolysin and leukocidin toxins, which function as two component toxins in the disruption and lysis of erythrocytes and leukocytes. Analysis of the aligned sequences of alpha-hemolysin, gamma-hemolysin, and leukocidin in the context of the alpha-hemolysin heptamer structure supports the conclusion that even though the level of sequence identity between alpha-hemolysin and the gamma-hemolysin and leukocidin toxins is in the so-called twilight zone, the three-dimensional structures of the protomers are probably conserved. By analogy with alpha-hemolysin, gamma-hemolysin and leukocidin may also form oligomeric, transmembrane channels in which an antiparallel beta-barrel constitutes the primary membrane-embedded domain.