2YYJ image
Entry Detail
PDB ID:
2YYJ
Keywords:
Title:
Crystal structure of the oxygenase component (HpaB) of 4-hydroxyphenylacetate 3-monooxygenase complexed with FAD and 4-hydroxyphenylacetate
Biological Source:
Source Organism:
PDB Version:
Deposition Date:
2007-04-30
Release Date:
2007-09-04
Method Details:
Experimental Method:
Resolution:
1.66 Å
R-Value Free:
0.16
R-Value Work:
0.15
Space Group:
I 2 2 2
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:4-hydroxyphenylacetate-3-hydroxylase
Chain IDs:A
Chain Length:481
Number of Molecules:1
Biological Source:Thermus thermophilus
Primary Citation
Crystal Structure of the Oxygenase Component (HpaB) of the 4-Hydroxyphenylacetate 3-Monooxygenase from Thermus thermophilus HB8
J.Biol.Chem. 282 33107 33117 (2007)
PMID: 17804419 DOI: 10.1074/jbc.M703440200

Abstact

The 4-hydroxyphenylacetate (4HPA) 3-monooxygenase is involved in the initial step of the 4HPA degradation pathway and catalyzes 4HPA hydroxylation to 3,4-dihydroxyphenylacetate. This enzyme consists of two components, an oxygenase (HpaB) and a reductase (HpaC). To understand the structural basis of the catalytic mechanism of HpaB, crystal structures of HpaB from Thermus thermophilus HB8 were determined in three states: a ligand-free form, a binary complex with FAD, and a ternary complex with FAD and 4HPA. Structural analysis revealed that the binding and dissociation of flavin are accompanied by conformational changes of the loop between beta5 and beta6 and of the loop between beta8 and beta9, leading to preformation of part of the substrate-binding site (Ser-197 and Thr-198). The latter loop further changes its conformation upon binding of 4HPA and obstructs the active site from the bulk solvent. Arg-100 is located adjacent to the putative oxygen-binding site and may be involved in the formation and stabilization of the C4a-hydroperoxyflavin intermediate.

Legend

Protein

Chemical

Disease

Primary Citation of related structures