1t7y
From Proteopedia
(New page: 200px<br /> <applet load="1t7y" size="450" color="white" frame="true" align="right" spinBox="true" caption="1t7y, resolution 2.80Å" /> '''Zn-alpha-2-glycopro...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1t7y.gif|left|200px]]<br /> | + | [[Image:1t7y.gif|left|200px]]<br /><applet load="1t7y" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1t7y" size=" | + | |
caption="1t7y, resolution 2.80Å" /> | caption="1t7y, resolution 2.80Å" /> | ||
'''Zn-alpha-2-glycoprotein; baculo-ZAG PEG 200, no glycerol'''<br /> | '''Zn-alpha-2-glycoprotein; baculo-ZAG PEG 200, no glycerol'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Zn-alpha2-glycoprotein (ZAG) is a 41 kDa soluble protein that is present | + | 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== | ==About this Structure== | ||
| - | 1T7Y is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with NAG as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1T7Y is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=NAG:'>NAG</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1T7Y OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 13: | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Bjorkman, P | + | [[Category: Bjorkman, P J.]] |
| - | [[Category: Delker, S | + | [[Category: Delker, S L.]] |
| - | [[Category: Jr., A | + | [[Category: Jr., A P.West.]] |
| - | [[Category: Kennedy, M | + | [[Category: Kennedy, M W.]] |
[[Category: McDermott, L.]] | [[Category: McDermott, L.]] | ||
[[Category: NAG]] | [[Category: NAG]] | ||
[[Category: mhc class i homolog]] | [[Category: mhc class i homolog]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:10:52 2008'' |
Revision as of 13:10, 21 February 2008
|
Zn-alpha-2-glycoprotein; baculo-ZAG PEG 200, no glycerol
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
1T7Y 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 Thu Feb 21 15:10:52 2008
