Malghani M S, Fang Y, Cheley S, Bayley H, Yang J
Department of Physics, University of Vermont, Burlington 05405, USA.
Microsc Res Tech. 1999 Mar 1;44(5):353-6. doi: 10.1002/(SICI)1097-0029(19990301)44:5<353::AID-JEMT6>3.0.CO;2-0.
Atomic force microscopy has been used to study self-assembled structures of two alpha-hemolysin mutants. For a mutant (alphaHL-H5) that was locked into the prepore state on fluid phase egg-PC membranes, we visualized, for the first time, heptameric prepores and showed that the 7-fold axis in the prepore lies perpendicular to the membrane surface. For another mutant (TCM) with the transmembrane domain, the self-assembled oligomer that assumes the conformation of the fully assembled pore is also a heptamer. These results show that heptamers are the preferred oligomerization state of alpha-hemolysin.
原子力显微镜已被用于研究两种α-溶血素突变体的自组装结构。对于一种在液相卵-磷脂酰胆碱（egg-PC）膜上锁定在孔前体状态的突变体（αHL-H5），我们首次可视化了七聚体孔前体，并表明孔前体中的七重轴垂直于膜表面。对于另一种具有跨膜结构域的突变体（TCM），呈现完全组装孔构象的自组装寡聚体也是七聚体。这些结果表明七聚体是α-溶血素的首选寡聚化状态。
