The Three-dimensional Structure of 4-Hydroxybenzoyl-CoA Thioesterase from Pseudomonas sp. Strain CBS-3

Abstract

The soil-dwelling microbe, Pseudomonas sp. strain CBS-3, has attracted recent attention due to its ability to survive on 4-chlorobenzoate as its sole carbon source. The biochemical pathway by which this organism converts 4-chlorobenzoate to 4-hydroxybenzoate consists of three enzymes: 4-chlorobenzoyl-CoA ligase, 4-chlorobenzoyl-CoA dehalogenase, and 4-hydroxybenzoyl-CoA thioesterase. Here we describe the three-dimensional structure of the thioesterase determined to 2.0-Å resolution. Each subunit of the homotetramer is characterized by a five-stranded anti-parallel ␤-sheet and three major ␣-helices. While previous amino acid sequence analyses failed to reveal any similarity between this thioesterase and other known proteins, the results from this study clearly demonstrate that the molecular architecture of 4-hydroxybenzoyl-CoA thioesterase is topologically equivalent to that observed for ␤-hydroxydecanoyl thiol ester dehydrase from Escherichia coli. On the basis of the structural similarity between these two enzymes, the active site of the thioesterase has been identified and a catalytic mechanism proposed.

Structural basis for recruitment of tandem hotdog domains in acyl-CoA thioesterase 7 and its role in inflammation

“…1 c and d). Other reported oligomeric structures of microbial thioesterases include dimers (20,21) and different tetrameric arrangements (14,22,23).…”

“…long-chain acyl-CoA substrates with fatty acid chains of [8][9][10][11][12][13][14][15][16] carbon atoms (C 8 -C 16 ) (7,13). Acot7 contains a pair of fused thioesterase domains that share Ϸ30% sequence identity, with each thioesterase domain predicted to have the hotdog fold structure with an ␣-helix sausage wrapped by a ␤-sheet bun (14)(15)(16).…”

“…Acot7 contains a pair of fused thioesterase domains that share Ϸ30% sequence identity, with each thioesterase domain predicted to have the hotdog fold structure with an ␣-helix sausage wrapped by a ␤-sheet bun (14)(15)(16).…”

The crystal structure of palmitoyl protein thioesterase 1 and the molecular basis of infantile neuronal ceroid lipofuscinosis

“…The second, 4-hydroxybenzoyl-CoA thioesterase from Pseudomonas sp. strain CBS-3 (13), an enzyme of interest in bioremediation, is unrelated in both structure and mechanism to the ␣͞␤ hydrolases. PPT1 represents the only eukaryotic thioesterase to be examined at atomic resolution.…”

Crystal structure of a putative acyl‐CoA thioesterase from Xanthomonas campestris (XC229) adopts a tetrameric hotdog fold of ϵγ mode

“…1 Interestingly, these enzymes involved in the degradation of environmental pollutants contain a unique nucleophilic Asp residue in the active site, 1,2,4,7 contrary to those using active site Ser/Cys residues commonly observed in the thioesterase family of fatty acid metabolism. 8,9 XC229 (gi|21112185) from a soil-dwelling plant pathogen Xanthomonas campestris pv.…”