PDBsum entry: 1pxc

Oxidoreductase

PDB id: 1pxc

Contents

Protein chain

394 a.a. *

Ligands

FAD

PHB

Waters ×191

* Residue conservation analysis

PDB id:

1pxc

Name:

Oxidoreductase

Title:

Crystal structures of mutant pseudomonas aeruginosa p-hydrox hydroxylase: the tyr201phe, tyr385phe, and asn300asp varian

Structure:

P-hydroxybenzoate hydroxylase. Chain: a. Engineered: yes

Source:

Pseudomonas aeruginosa. Organism_taxid: 287

Biol. unit:

Dimer (from PQS)

Resolution:

2.10Å R-factor: 0.178

Authors:

M.S.Lah,B.A.Palfey,H.A.Schreuder,M.L.Ludwig

Key ref:

M.S.Lah et al. (1994). Crystal structures of mutant Pseudomonas aeruginosa p-hydroxybenzoate hydroxylases: the Tyr201Phe, Tyr385Phe, and Asn300Asp variants. Biochemistry, 33, 1555-1564. PubMed id: 8312276 DOI: 10.1021/bi00172a036

Date:

27-Sep-94 Release date: 27-Feb-95

Protein chain

P20586  (PHHY_PSEAE) -  P-hydroxybenzoate hydroxylase

Seq: 394 a.a.

Struc: 394 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.1.14.13.2 - 4-hydroxybenzoate 3-monooxygenase.
• Pathway: Benzoate Metabolism
• Reaction: 4-hydroxybenzoate + NADPH + O₂ = protocatechuate + NADP⁺ + H₂O

4-hydroxybenzoate (Bound ligand (Het Group name = PHB) corresponds exactly) + NADPH + O(2) = protocatechuate + NADP(+) + H(2)O

• Cofactor: FAD

FAD (Bound ligand (Het Group name = FAD) corresponds exactly)

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

 Gene Ontology (GO) functional annotation 

• Biological process: metabolic process (4 terms)
• Biochemical function: oxidoreductase activity (4 terms)

reference

DOI no: 10.1021/bi00172a036

Biochemistry 33:1555-1564 (1994)

PubMed id: 8312276

Crystal structures of mutant Pseudomonas aeruginosa p-hydroxybenzoate hydroxylases: the Tyr201Phe, Tyr385Phe, and Asn300Asp variants.

M.S.Lah, B.A.Palfey, H.A.Schreuder, M.L.Ludwig.

ABSTRACT

Structures of the mutant p-hydroxybenzoate hydroxylases, Tyr201Phe, Tyr385Phe, and Asn300Asp, each complexed with the substrate p-OHB have been determined by X-ray crystallography. Crystals of these three mutants of the Pseudomonas aeruginosa enzyme, which differs from the wild-type Pseudomonas fluorescens enzyme at two surface positions (228 and 249), were isomorphous with crystals of the wild-type P. fluorescens enzyme, allowing the mutant structures to be determined by model building and refinement, starting from the coordinates for the oxidized P. fluorescens PHBH-3,4-diOHB complex [Schreuder, H.A., van der Laan, J.M., Hol, W.G.J., & Drenth, J. (1988) J. Mol. Biol. 199, 637-648]. The R factors for the structures described here are: Tyr385Phe, 0.178 for data from 40.0 to 2.1 A; Tyr201Phe, 0.203 for data from 40.0 to 2.3 A; and Asn300Asp, 0.193 for data from 40.0 to 2.3 A. The functional effects of the Tyr201Phe and Tyr385Phe mutations, described earlier [Entsch, B., Palfey, B.A., Ballou, D.P., & Massey, V. (1991) J. Biol. Chem. 266, 17341-17349], were rationalized with the assumption that the mutations perturbed the hydrogen-bonding interactions of the tyrosine residues but caused no other changes in the enzyme structure. In agreement with these assumptions, the positions of the substrate, the flavin, and the modified residues are not altered in the Tyr385Phe and Tyr201Phe structures. In contrast, substitution of Asp for Asn at residue 300 has more profound effects on the enzyme structure. The side chain of Asp300 moves away from the flavin, disrupting the interactions of the carboxamide group with the flavin O(2) atom, and the alpha-helix H10 that begins at residue 297 is displaced, altering its dipole interactions with the flavin ring. The functional consequences of these changes in the enzyme structure and of the introduction of the carboxyl group at 300 are described and discussed in the accompanying paper (Palfey et al., 1994b).