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:1986
卷号:83
期号:5
页码:1320-1324
DOI:10.1073/pnas.83.5.1320
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Exotoxin A of Pseudomonas aeruginosa is a secreted bacterial toxin capable of translocating a catalytic domain into mammalian cells and inhibiting protein synthesis by the ADP-ribosylation of cellular elongation factor 2. The protein is a single polypeptide chain of 613 amino acids. The x-ray crystallographic structure of exotoxin A, determined to 3.0-A resolution, shows the following: an amino-terminal domain, composed primarily of antiparallel beta-structure and comprising approximately half of the molecule; a middle domain composed of alpha-helices; and a carboxyl-terminal domain comprising approximately one-third of the molecule. The carboxyl-terminal domain is the ADP-ribosyltransferase of the toxin. The other two domains are presumably involved in cell receptor binding and membrane translocation.