1h2f
From Proteopedia
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BACILLUS STEAROTHERMOPHILUS PHOE (PREVIOUSLY KNOWN AS YHFR) IN COMPLEX WITH TRIVANADATE
Overview
Bacillus stearothermophilus phosphatase PhoE is a member of the, cofactor-dependent phosphoglycerate mutase superfamily possessing broad, specificity phosphatase activity. Its previous structural determination in, complex with glycerol revealed probable bases for its efficient hydrolysis, of both large, hydrophobic, and smaller, hydrophilic substrates. Here we, report two further structures of PhoE complexes, to higher resolution of, diffraction, which yield a better and thorough understanding of its, catalytic mechanism. The environment of the phosphate ion in the catalytic, site of the first complex strongly suggests an acid-base catalytic, function for Glu83. It also reveals how the C-terminal tail ordering is, linked to enzyme activation on phosphate binding by a different mechanism, to that seen in Escherichia coli phosphoglycerate mutase. The second, complex structure with an unusual doubly covalently bound trivanadate, shows how covalent modification of the phosphorylable His10 is accompanied, by small structural changes, presumably to catalytic advantage. When, compared with structures of related proteins in the cofactor-dependent, phosphoglycerate mutase superfamily, an additional phosphate ligand, Gln22, is observed in PhoE. Functional constraints lead to the, corresponding residue being conserved as Gly in, fructose-2,6-bisphosphatases and Thr/Ser/Cys in phosphoglycerate mutases., A number of sequence annotation errors in databases are highlighted by, this analysis. B. stearothermophilus PhoE is evolutionarily related to a, group of enzymes primarily present in Gram-positive bacilli. Even within, this group substrate specificity is clearly variable highlighting the, difficulties of computational functional annotation in the, cofactor-dependent phosphoglycerate mutase superfamily.
About this Structure
1H2F is a Single protein structure of sequence from Geobacillus stearothermophilus with PO4 and VA3 as ligands. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Structures of phosphate and trivanadate complexes of Bacillus stearothermophilus phosphatase PhoE: structural and functional analysis in the cofactor-dependent phosphoglycerate mutase superfamily., Rigden DJ, Littlejohn JE, Henderson K, Jedrzejas MJ, J Mol Biol. 2003 Jan 17;325(3):411-20. PMID:12498792
Page seeded by OCA on Tue Dec 18 15:53:46 2007
