3cd4
From Proteopedia
REFINEMENT AND ANALYSIS OF THE FIRST TWO DOMAINS OF HUMAN CD4
Overview
The structure of a fragment of human CD4 containing two immunoglobulin (Ig)-like domains has been determined by X-ray crystallography and refined at 2.2 A resolution. The structure determination involved iterative building and simulated-annealing refinement, beginning with a partial model. Comparison of domain 1 with an Ig variable domain shows that CD4 has a long and prominent CDR2-like loop (the C"C" corner) and shortened CC' and FG loops (which mediate dimerization in IgV modules). Comparison of domain 2 with Ig modules and domain 1 shows that it can be described as a truncated Ig V domain, in which strands C" and D are deleted. The intersheet disulfide in domain 2 is absent, and there is an altered packing of the two beta-sheets together with a remodeling of the hydrophobic core. The interface between domains 1 and 2 is a lap joint with an extensive hydrophobic surface. The key features of domain 1 that contribute to the interface are found at corresponding positions in domain 2, leading us to propose that the contact between domains 2 and 3 will resemble the one between domains 1 and 2.
About this Structure
3CD4 is a Single protein structure of sequence from Homo sapiens. This structure supersedes the now removed PDB entry 2cd4. Full crystallographic information is available from OCA.
Reference
Refinement and analysis of the structure of the first two domains of human CD4., Garrett TP, Wang J, Yan Y, Liu J, Harrison SC, J Mol Biol. 1993 Dec 5;234(3):763-78. PMID:8254672 Page seeded by OCA on Sun May 4 21:36:31 2008
