2j5s

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spinqualitylabelsall models 2j5s, resolution 1.57Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

STRUCTURAL OF ABDH, A BETA-DIKETONE HYDROLASE FROM THE CYANOBACTERIUM ANABAENA SP. PCC 7120 BOUND TO (S)-3-OXOCYCLOHEXYL ACETIC ACID

Overview

The gene alr4455 from the well-studied cyanobacterium Anabaena sp. PCC, 7120 encodes a crotonase orthologue that displays beta-diketone hydrolase, activity. Anabaena beta-diketone hydrolase (ABDH), in common with, 6-oxocamphor hydrolase (OCH) from Rhodococcus sp. NCIMB 9784, catalyzes, the desymmetrization of bicyclo[2.2.2]octane-2,6-dione to yield, [(S)-3-oxocyclohexyl]acetic acid, a reaction unusual among the crotonase, superfamily as the substrate is not an acyl-CoA thioester. The structure, of ABDH has been determined to a resolution of 1.5 A in both native and, ligand-bound forms. ABDH forms a hexamer similar to OCH and features one, active site per enzyme monomer. The arrangement of side chains in the, active site indicates that while the catalytic chemistry may be conserved, in OCH orthologues, the structural determinants of substrate specificity, are different. In the active site of ligand-bound forms that had been, cocrystallized with the bicyclic diketone substrate, bicyclo[2.2.2]octane-2,6-dione was found the product of the asymmetric, enzymatic retro-Claisen reaction [(S)-3-oxocyclohexyl]acetic acid. The, structures of ABDH in both native and ligand-bound forms reveal further, details about structural variation and modes of coenzyme A-independent, activity within the crotonases and provide further evidence of a wider, suprafamily of enzymes that have recruited the crotonase fold for the, catalysis of reactions other than those regularly attributed to canonical, superfamily members.

About this Structure

2J5S is a Single protein structure of sequence from Anabaena sp. with and as ligands. Active as Beta-diketone hydrolase, with EC number 3.7.1.7 Known structural/functional Site: . Full crystallographic information is available from OCA.

Reference

Structural characterization of a beta-diketone hydrolase from the cyanobacterium Anabaena sp. PCC 7120 in native and product-bound forms, a coenzyme A-independent member of the crotonase suprafamily., Bennett JP, Whittingham JL, Brzozowski AM, Leonard PM, Grogan G, Biochemistry. 2007 Jan 9;46(1):137-44. PMID:17198383

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