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:1977
卷号:74
期号:11
页码:5140-5144
DOI:10.1073/pnas.74.11.5140
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:We have examined the low-resolution structure of a complete human IgG1 using known domain coordinates from crystallographic investigations of immunoglobulin fragment structures. Our results indicate that the Fc portion of this molecule has a structure similar to that of an isolated Fc fragment, with the carbohydrate moiety playing a central role as the principal contact between the CH2 domains. Carbohydrate also forms a large part of the interface between the Fc and Fab regions. The relative orientations of the variable and constant portions of the Fab regions are intermediate between those reported previously, emphasizing the flexibility of the switch region. These data do not support a two-state allosteric model such as has been proposed for antibody effector functions.