Open AccessThree-dimensional structure of an intact human immunoglobulin.
Author(s) -
Enid W. Silverton,
Manuel A. Navia,
David R. Davies
Publication year - 1977
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.74.11.5140
Subject(s) - allosteric regulation , immunoglobulin fab fragments , immunoglobulin domain , fragment crystallizable region , antibody , chemistry , moiety , protein structure , molecule , immunoglobulin g , fragment (logic) , stereochemistry , immunoglobulin fc fragments , crystallography , biology , immunoglobulin light chain , biochemistry , receptor , computer science , immunology , complementarity determining region , organic chemistry , programming language
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.