Work

p-Hydroxyphenylacetate-3-hydroxylase. A two-protein component enzyme.

Year: 1992

Type: article

Abstract: p-Hydroxyphenylacetate-3-hydroxylase, an inducible enzyme isolated from the soil bacterium Pseudomonas putida, catalyzes the conversion of p-hydroxyphenylacetate to 3,4-dihydroxyphenylacetate. The enzyme requires two protein components: a flavoprotein and a colorless protein referred to as the coupling protein. The flavoprotein alone in the presence of p-hydroxyphenylacetate and substrate analogs catalyzes the wasteful oxidation of NADH with the stoichiometric generation of H2O2. A 1:1 complex of the flavoprotein and coupling protein is required for stoichiometric product formation. Such complex formation also eliminates the nonproductive NADH oxidase activity of the flavoprotein. A new assay measuring the product formation activity of the enzyme was developed using homoprotocatechuate-2,3-dioxygenase, as monitoring the oxidation of NADH was not sufficient to demonstrate enzyme activity. The coupling protein does not seem to have any redox center in it. Thus, this 2-component flavin hydroxylase resembles the other aromatic hydroxylases in that the only redox chromophore present is FAD.

Source: Journal of Biological Chemistry

DOI: 10.1016/s0021-9258(18)35687-4

Authors: U Arunachalam, V Massey, C.S. Vaidyanathan

Institution: University of Michigan

Language: English

Topic: Microbial bioremediation and biosurfactants

Subfield: Pollution

Field: Environmental Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,430

Funder: National Institute of General Medical Sciences