Purification and properties of NADPH-dependent aldehyde reductase from human liver

J Biol Chem. 1977 Jun 10;252(11):3821-8.

Abstract

An aldehyde reductase (EC 1.1.1.2) from human liver has been purified to homogeneity. The enzyme is NADPH-dependent, prefers aromatic to aliphatic aldehydes as substrates, and is inhibited by barbiturates and hydantoins. The following physicochemical parameters were determined: molecular weight, 36,200; sedimentation coefficient, 2.9 S; Stokes radius, 2.65 nm; isoelectric point, pH 5.3; extinction coefficient at 280 nm, 54,300 M-1 cm-1. Results from polyacrylamide gel electrophoresis with and without sodium dodecyl sulfate, gel filtration, and ultracentrifugation suggest a monomeric structure. On molecule of NADPH binds to the enzyme causing a red shift of the coenzyme absorption maximum from 340 to 352 nm. The amino acid composition has been determined and a partial specific volume of 0.74 was computed from these data. An alpha-helicity of 7 and 18% was estimated from the ellipticities at 208 and 222 nm, respectively. Combination of the most reactive thiol group with p-mercuribenzoate does not cause loss of catalytic activity. Inactivation occurs when more than one thiol group is modified. The presence of NADPH or NADP+ prevents loss of activity by thiol modification. The comparison of structural features of aldehyde reductase with other monomeric and oligomeric dehydrogenases suggest similarities of aldehyde reductase with octopine dehydrogenase.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Alcohol Oxidoreductases* / isolation & purification
  • Alcohol Oxidoreductases* / metabolism
  • Aldehydes / metabolism*
  • Amino Acids / analysis
  • Circular Dichroism
  • Female
  • Humans
  • Hydantoins / pharmacology
  • Hydrogen-Ion Concentration
  • Isoelectric Point
  • Kinetics
  • Liver / enzymology*
  • Male
  • Molecular Weight
  • NADP / metabolism
  • Phenobarbital / pharmacology
  • Pyrazoles / pharmacology
  • Spectrophotometry

Substances

  • Aldehydes
  • Amino Acids
  • Hydantoins
  • Pyrazoles
  • NADP
  • Alcohol Oxidoreductases
  • Phenobarbital