2gsu
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="2gsu" size="350" color="white" frame="true" align="right" spinBox="true" caption="2gsu, resolution 2.00Å" /> '''Structure of Xac Nuc...)
Next diff →
Revision as of 18:07, 29 January 2008
|
Structure of Xac Nucleotide Pyrophosphatase/Phosphodiesterase in Complex with AMP
Overview
The rapid expansion of the amount of genomic and structural data has, provided many examples of enzymes with evolutionarily related active sites, that catalyze different reactions. Functional comparisons of these active, sites can provide insight into the origins of the enormous catalytic, proficiency of enzymes and the evolutionary changes that can lead to, different enzyme activities. The alkaline phosphatase (AP) superfamily is, an ideal system to use in making such comparisons given the extensive data, available on both nonenzymatic and enzymatic phosphoryl transfer, reactions. Some superfamily members, such as AP itself, preferentially, hydrolyze phosphate monoesters, whereas others, such as nucleotide, pyrophosphatase/phosphodiesterase (NPP), preferentially hydrolyze, phosphate diesters. We have measured rate constants for NPP-catalyzed, hydrolysis of phosphate diesters and monoesters. NPP preferentially, catalyzes diester hydrolysis by factors of 10(2)-10(6), depending on the, identity of the diester substrate. To identify features of the NPP active, site that could lead to preferential phosphate diester hydrolysis, we have, determined the structure of NPP in the absence of ligands and in complexes, with vanadate and AMP. Comparisons to existing structures of AP reveal, bimetallo cores that are structurally indistinguishable, but there are, several distinct structural features outside of the conserved bimetallo, site. The structural and functional data together suggest that some of, these distinct functional groups provide specific substrate binding, interactions, whereas others tune the properties of the bimetallo active, site itself to discriminate between phosphate diester and monoester, substrates.
About this Structure
2GSU is a Single protein structure of sequence from Xanthomonas axonopodis pv. citri str. 306 with and as ligands. Active as Nucleotide diphosphatase, with EC number 3.6.1.9 Full crystallographic information is available from OCA.
Reference
Structural and functional comparisons of nucleotide pyrophosphatase/phosphodiesterase and alkaline phosphatase: implications for mechanism and evolution., Zalatan JG, Fenn TD, Brunger AT, Herschlag D, Biochemistry. 2006 Aug 15;45(32):9788-803. PMID:16893180
Page seeded by OCA on Tue Jan 29 20:07:22 2008
