Formation of beta-hydroxyisovalerate by an alpha-ketoisocaproate oxygenase in human liver

Metabolism. 1983 Feb;32(2):160-4. doi: 10.1016/0026-0495(83)90223-8.


Previously we demonstrated the occurrence of a soluble dioxygenase in rat liver which converts alpha-ketoisocaproic acid (the keto acid analog of leucine) to beta-hydroxyisovaleric acid. Herein we show that human liver contains a similar soluble enzyme which converts alpha-ketoisocaproate to beta-hydroxisovaleric acid. We suggest this enzyme functions as a "safety valve" in liver to help prevent excessive accumulation of alpha-ketoisocaproate.

Publication types

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

MeSH terms

  • Chemical Phenomena
  • Chemistry
  • Dioxygenases*
  • Humans
  • In Vitro Techniques
  • Liver / enzymology*
  • Oxygenases / metabolism*
  • Solubility
  • Valerates / biosynthesis*


  • Valerates
  • beta-hydroxyisovaleric acid
  • Oxygenases
  • Dioxygenases
  • alpha-ketoisocaproate oxygenase