期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1980
卷号:77
期号:2
页码:952-956
DOI:10.1073/pnas.77.2.952
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:A projection, at 15- to 20-A resolution, is presented of the structure of the membrane-bound acetylcholine receptor protein from Torpedo marmorata. The projection has its axis perpendicular to the membrane plane; its main contribution originates from a hydrated portion of the protein, which extends from the membrane into the aqueous medium. The structure is distinctly asymmetric, with individual morphological subunits barely resolvable. These results have been obtained by noncrystallographic averaging, using correlation functions, applied to electron micrographs of receptor-rich membrane fragments. The micrographs had been taken with minimal beam exposure in a scanning transmission electron microscope.