Takeda Kein, Tanaka Yoshikazu, Abe Naoki, Kaneko Jun
Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, Aramaki Aza Aoba, Sendai 980-8572, Japan.
Laboratory of Applied Biological Molecular Science, Graduate School of Life Sciences, Tohoku University, Katahira 980-8577, Sendai, Japan.
Toxicon. 2018 Dec 1;155:43-48. doi: 10.1016/j.toxicon.2018.10.002. Epub 2018 Oct 10.
The β-strand stem release system of staphylococcal β-barrel pore-forming toxin γ-hemolysin was investigated. Mutations at K15 and R16 in the cap domain of Hlg2 decreased hemolytic activity more markedly than their effect on erythrocyte binding. In addition, D122N mutation of LukF prestem lost the activity with Hlg2 R16A, indicating that electrostatic interactions between residues in the Hlg2 cap and prestem of adjacent LukF in the ring-shaped complex might serve as a switch for stem release.
对葡萄球菌β桶状成孔毒素γ溶血素的β链茎释放系统进行了研究。Hlg2帽结构域中K15和R16位点的突变对溶血活性的降低比其对红细胞结合的影响更为明显。此外，LukF前茎的D122N突变使与Hlg2 R16A的活性丧失，这表明在环形复合物中，Hlg2帽结构域中的残基与相邻LukF前茎之间的静电相互作用可能作为茎释放的开关。
