Purification and characterization of methylmalonate-semialdehyde dehydrogenase from rat liver. Identity to malonate-semialdehyde dehydrogenase

G. W. Goodwin, P. M. Rougraff, E. J. Davis, R. A. Harris

Research output: Contribution to journalArticle

65 Scopus citations


Methylmalonate semialdehyde dehydrogenase was purified from rat liver in order to define the distal portion of valine catabolism and related pathways in mammals. The purified enzyme is active with malonate semialdehyde and consumes both stereoisomers of methylmalonate semialdehyde, implicating a single semialdehyde dehydrogenase in the catabolism of valine, thymine, and compounds catabolized by way of β-alanine. The oxidation of malonate and methylmalonate semialdehydes by this enzyme is CoA-dependent, the products being acetyl-CoA and propionyl-CoA, respectively. Expected activity with ethylmalonate semialdehyde as substrate was not found. Methylmalonate semialdehyde dehydrogenase was separated on DEAE-Sephacel into two isoforms which differ in mobility during nondenaturing polyacrylamide gel electrophoresis. The two forms are immunologically cross-reactive and exhibit the same N-terminal sequence, suggesting that one form is the product of the other. The monomer molecular mass, determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, was 58 kDa. The native molecular mass, estimated by gel filtration, was 250 kDa, suggesting a tetrameric structure.

Original languageEnglish (US)
Pages (from-to)14965-14971
Number of pages7
JournalJournal of Biological Chemistry
Issue number25
StatePublished - Jan 1 1989


ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Cite this