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1t7x
From Proteopedia
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Zn-alpha-2-glycoprotein; refolded CHO-ZAG PEG 400
Overview
Zn-alpha2-glycoprotein (ZAG) is a 41 kDa soluble protein that is present, in most bodily fluids. The previously reported 2.8 A crystal structure of, ZAG isolated from human serum demonstrated the structural similarity, between ZAG and class I major histocompatibility complex (MHC) molecules, and revealed a non-peptidic ligand in the ZAG counterpart of the MHC, peptide-binding groove. Here we present crystallographic studies to, explore further the nature of the non-peptidic ligand in the ZAG groove., Comparison of the structures of several forms of recombinant ZAG, including a 1.95 A structure derived from ZAG expressed in insect cells, suggests that the non-peptidic ligand in the current structures and in the, structure of serum ZAG is a polyethylene glycol (PEG), which is present in, the crystallization conditions used. Further support for PEG binding in, the ZAG groove is provided by the finding that PEG displaces a, fluorophore-tagged fatty acid from the ZAG binding site. From these, results we hypothesize that our purified forms of ZAG do not contain a, bound endogenous ligand, but that the ZAG groove is capable of binding, hydrophobic molecules, which may relate to its function.
About this Structure
1T7X is a Single protein structure of sequence from Homo sapiens with as ligand. Full crystallographic information is available from OCA.
Reference
Crystallographic studies of ligand binding by Zn-alpha2-glycoprotein., Delker SL, West AP Jr, McDermott L, Kennedy MW, Bjorkman PJ, J Struct Biol. 2004 Nov;148(2):205-13. PMID:15477100
Page seeded by OCA on Fri Feb 15 16:55:37 2008
