Substrate Specificity of a Recombinant Chicken Beta-Carotene 15,15'-monooxygenase That Converts Beta-Carotene Into Retinal

Biotechnol Lett. 2009 Mar;31(3):403-8. doi: 10.1007/s10529-008-9873-4. Epub 2008 Nov 2.

Abstract

The recombinant beta-carotene 15,15'-monooxygenase from chicken liver was purified as a single 60 kDa band by His-Trap HP and Resource Q chromatography. It had a molecular mass of 240 kDa by gel filtration indicating the native form to be tetramer. The enzyme converted beta-carotene under maximal conditions (pH 8.0 and 37 degrees C) with a k (cat) of 1.65 min(-1) and a K (m) of 26 muM and its conversion yield of beta-carotene to retinal was 120% (mol mol(-1)). The enzyme displayed catalytic efficiency and conversion yield for beta-carotene, beta-cryptoxanthin, beta-apo-8'-carotenal, beta-apo-4'-carotenal, alpha-carotene and gamma-carotene in decreasing order but not for zeaxanthin, lutein, beta-apo-12'-carotenal and lycopene, suggesting that the presence of one unsubstituted beta-ionone ring in a substrate with a molecular weight greater than C(30) seems to be essential for enzyme activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chickens
  • Chromatography, Gel
  • Kinetics
  • Liver / enzymology*
  • Molecular Weight
  • Norisoprenoids / metabolism
  • Protein Multimerization
  • Protein Subunits
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Retinaldehyde / metabolism*
  • Substrate Specificity
  • beta Carotene / metabolism*
  • beta-Carotene 15,15'-Monooxygenase / chemistry
  • beta-Carotene 15,15'-Monooxygenase / genetics
  • beta-Carotene 15,15'-Monooxygenase / isolation & purification
  • beta-Carotene 15,15'-Monooxygenase / metabolism*

Substances

  • Norisoprenoids
  • Protein Subunits
  • Recombinant Proteins
  • beta Carotene
  • beta-ionone
  • beta-Carotene 15,15'-Monooxygenase
  • Retinaldehyde