PDBsum entry 2vss

Lyase

PDB id: 2vss

Contents

Protein chains

(+ 0 more) 239 a.a. *

Ligands

ACO ×4

V55

Waters ×316

* Residue conservation analysis

PDB id:

2vss

Name:

Lyase

Title:

Wild-type hydroxycinnamoyl-coa hydratase lyase in complex with acetyl- coa and vanillin

Structure:

P-hydroxycinnamoyl coa hydratase/lyase. Chain: a, b, c, d. Synonym: hydroxycinnamoyl-coa hydratase-lyase. Engineered: yes. P-hydroxycinnamoyl coa hydratase/lyase. Chain: e. Synonym: hydroxycinnamoyl-coa hydratase-lyase. Engineered: yes. P-hydroxycinnamoyl coa hydratase/lyase.

Source:

Pseudomonas fluorescens. Organism_taxid: 294. Strain: an103. Expressed in: escherichia coli. Expression_system_taxid: 469008. Other_details: institute of food research, norwich u.K.. Other_details: institute of food research, norwich u.K.

Resolution:

2.22Å R-factor: 0.186 R-free: 0.242

Authors:

J.P.Bennett,L.M.Bertin,A.M.Brzozowski,N.J.Walton,G.Grogan

Key ref:

J.P.Bennett et al. (2008). A ternary complex of hydroxycinnamoyl-CoA hydratase-lyase (HCHL) with acetyl-CoA and vanillin gives insights into substrate specificity and mechanism. Biochem J, 414, 281-289. PubMed id: 18479250

Date:

29-Apr-08 Release date: 27-May-08

Protein chains

O69762  (HCHL_PSEFL) -  Hydroxycinnamoyl-CoA hydratase-lyase from Pseudomonas fluorescens

Seq: 276 a.a.

Struc: 239 a.a.

Enzyme reactions

• Enzyme class: E.C.4.1.2.61 - feruloyl-CoA hydratase/lyase.
• Reaction: (E)-feruloyl-CoA + H2O = vanillin + acetyl-CoA

(E)-feruloyl-CoA + H2O = vanillin (Bound ligand (Het Group name = ACO) corresponds exactly) + acetyl-CoA (Bound ligand (Het Group name = V55) corresponds exactly)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

Added reference

Biochem J 414:281-289 (2008)

PubMed id: 18479250

A ternary complex of hydroxycinnamoyl-CoA hydratase-lyase (HCHL) with acetyl-CoA and vanillin gives insights into substrate specificity and mechanism.

J.P.Bennett, L.Bertin, B.Moulton, I.J.Fairlamb, A.M.Brzozowski, N.J.Walton, G.Grogan.

ABSTRACT

HCHL (hydroxycinnamoyl-CoA hydratase-lyase) catalyses the biotransformation of feruloyl-CoA to acetyl-CoA and the important flavour-fragrance compound vanillin (4-hydroxy-3-methoxybenzaldehyde) and is exploited in whole-cell systems for the bioconversion of ferulic acid into natural equivalent vanillin. The reaction catalysed by HCHL has been thought to proceed by a two-step process involving first the hydration of the double bond of feruloyl-CoA and then the cleavage of the resultant beta-hydroxy thioester by retro-aldol reaction to yield the products. Kinetic analysis of active-site residues identified using the crystal structure of HCHL revealed that while Glu-143 was essential for activity, Ser-123 played no major role in catalysis. However, mutation of Tyr-239 to Phe greatly increased the K(M) for the substrate ferulic acid, fulfilling its anticipated role as a factor in substrate binding. Structures of WT (wild-type) HCHL and of the S123A mutant, each of which had been co-crystallized with feruloyl-CoA, reveal a subtle helix movement upon ligand binding, the consequence of which is to bring the phenolic hydroxyl of Tyr-239 into close proximity to Tyr-75 from a neighbouring subunit in order to bind the phenolic hydroxyl of the product vanillin, for which electron density was observed. The active-site residues of ligand-bound HCHL display a remarkable three-dimensional overlap with those of a structurally unrelated enzyme, vanillyl alcohol oxidase, that also recognizes p-hydroxylated aromatic substrates related to vanillin. The data both explain the observed substrate specificity of HCHL for p-hydroxylated cinnamate derivatives and illustrate a remarkable convergence of the molecular determinants of ligand recognition between the two otherwise unrelated enzymes.