1z84
From Proteopedia
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|GENE= AT5G18200 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=3702 Arabidopsis thaliana]) | |GENE= AT5G18200 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=3702 Arabidopsis thaliana]) | ||
|DOMAIN=<span class='plainlinks'>[http://www.ncbi.nlm.nih.gov/Structure/cdd/cddsrv.cgi?uid=cd00608 GalT], [http://www.ncbi.nlm.nih.gov/Structure/cdd/cddsrv.cgi?uid=COG1085 GalT]</span> | |DOMAIN=<span class='plainlinks'>[http://www.ncbi.nlm.nih.gov/Structure/cdd/cddsrv.cgi?uid=cd00608 GalT], [http://www.ncbi.nlm.nih.gov/Structure/cdd/cddsrv.cgi?uid=COG1085 GalT]</span> | ||
| - | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1z84 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1z84 OCA], [http://www.ebi.ac.uk/pdbsum/1z84 PDBsum | + | |RELATEDENTRY=[[1zwj|1ZWJ]], [[2gdk|2GDK]] |
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1z84 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1z84 OCA], [http://www.ebi.ac.uk/pdbsum/1z84 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1z84 RCSB]</span> | ||
}} | }} | ||
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[[Category: zinc]] | [[Category: zinc]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 01:31:48 2008'' |
Revision as of 22:31, 30 March 2008
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| , resolution 1.83Å | |||||||
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| Ligands: | , , | ||||||
| Gene: | AT5G18200 (Arabidopsis thaliana) | ||||||
| Domains: | GalT, GalT | ||||||
| Related: | 1ZWJ, 2GDK
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
X-ray structure of galt-like protein from arabidopsis thaliana at5g18200
Overview
The X-ray crystal structure of the At5g18200.1 protein has been determined to a nominal resolution of 2.30 A. The structure has a histidine triad (HIT)-like fold containing two distinct HIT-like motifs. The sequence of At5g18200.1 indicates a distant family relationship to the Escherichia coli galactose-1-P uridylyltransferase (GalT): the determined structure of the At5g18200.1 protein confirms this relationship. The At5g18200.1 protein does not demonstrate GalT activity but instead catalyzes adenylyl transfer in the reaction of ADP-glucose with various phosphates. The best acceptor among those evaluated is phosphate itself; thus, the At5g18200.1 enzyme appears to be an ADP-glucose phosphorylase. The enzyme catalyzes the exchange of (14)C between ADP-[(14)C]glucose and glucose-1-P in the absence of phosphate. The steady state kinetics of exchange follows the ping-pong bi-bi kinetic mechanism, with a k(cat) of 4.1 s(-)(1) and K(m) values of 1.4 and 83 microM for ADP-[(14)C]glucose and glucose-1-P, respectively, at pH 8.5 and 25 degrees C. The overall reaction of ADP-glucose with phosphate to produce ADP and glucose-1-P follows ping-pong bi-bi steady state kinetics, with a k(cat) of 2.7 s(-)(1) and K(m) values of 6.9 and 90 microM for ADP-glucose and phosphate, respectively, at pH 8.5 and 25 degrees C. The kinetics are consistent with a double-displacement mechanism that involves a covalent adenylyl-enzyme intermediate. The X-ray crystal structure of this intermediate was determined to 1.83 A resolution and shows the AMP group bonded to His(186). The value of K(eq) in the direction of ADP and glucose-1-P formation is 5.0 at pH 7.0 and 25 degrees C in the absence of a divalent metal ion, and it is 40 in the presence of 1 mM MgCl(2).
About this Structure
1Z84 is a Single protein structure of sequence from Arabidopsis thaliana. Full crystallographic information is available from OCA.
Reference
Structure and mechanism of an ADP-glucose phosphorylase from Arabidopsis thaliana., McCoy JG, Arabshahi A, Bitto E, Bingman CA, Ruzicka FJ, Frey PA, Phillips GN Jr, Biochemistry. 2006 Mar 14;45(10):3154-62. PMID:16519510
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