Honda T, Ni Y, Miwatani T, Adachi T, Kim J
Research Institute for Microbial Diseases, Osaka University, Japan.
Can J Microbiol. 1992 Nov;38(11):1175-80. doi: 10.1139/m92-192.
The hemolytic mechanism of thermostable direct hemolysin (TDH), a possible virulence factor of Vibrio parahaemolyticus, was studied. We demonstrated that TDH acts as a "pore-forming toxin" in temperature-dependent and -independent steps. The first temperature-dependent step requires only about 1-2 min incubation at 37 degrees C and makes a "pore" with a functional diameter of approximately 2 nm. The pore size was deduced from the molecular diameter of the colloidal inhibitory polysaccharides. The formation of the pores on TDH-treated erythrocyte membranes was also demonstrated by electron microscopic examination. The second step, which is a temperature-independent lytic step, causes the erythrocytes to swell owing to a colloidal osmotic influx of water via the "pores" into cells, resulting in erythrocyte lysis (or rupture) owing to increased intracellular pressure.
对副溶血性弧菌可能的毒力因子——耐热直接溶血素（TDH）的溶血机制进行了研究。我们证明，TDH在温度依赖性和非依赖性步骤中作为一种“成孔毒素”发挥作用。第一个温度依赖性步骤仅需要在37℃下孵育约1 - 2分钟，并形成一个功能直径约为2nm的“孔”。孔的大小是根据胶体抑制性多糖的分子直径推断出来的。通过电子显微镜检查也证实了在经TDH处理的红细胞膜上形成了孔。第二步是温度非依赖性的裂解步骤，由于水通过“孔”以胶体渗透的方式流入细胞，导致红细胞肿胀，由于细胞内压力增加而导致红细胞溶解（或破裂）。
