Purification and properties of 4-hydroxyphenylacetic acid 3-hydroxylase from Pseudomonas putida

Biochem Biophys Res Commun. 1988 Jul 29;154(2):537-43. doi: 10.1016/0006-291x(88)90173-8.

Abstract

4-Hydroxyphenylacetic acid 3-hydroxylase is a key enzyme in the pathway for the microbial degradation of phenylalanine, tyrosine and many aromatic amines. This enzyme was purified to homogeneity from Pseudomonas putida by affinity chromatography. The protein had a molecular weight of 91,000 and was a dimer of identical subunits. It was a typical external flavoprotein monooxygenase and showed an absolute requirement of NADH for activity. The enzyme had a pH optimum of 7.5 and the Km values for 4-hydroxyphenylacetic acid and NADH were 2 x 10(-4) M and 5.9 x 10(-5) M respectively. It was strongly inhibited by heavy metal ions and thiol reagents, suggesting the possible involvement of -SH group(s) in enzyme reaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Hydrogen-Ion Concentration
  • Mixed Function Oxygenases / isolation & purification*
  • Molecular Weight
  • NAD / metabolism
  • Phenylacetates / metabolism
  • Pseudomonas / enzymology*
  • Substrate Specificity

Substances

  • Phenylacetates
  • NAD
  • 4-hydroxyphenylacetic acid
  • Mixed Function Oxygenases
  • 4-hydroxyphenylacetate 3-monooxygenase