YjgF is required for isoleucine biosynthesis when Salmonella enterica is grown on pyruvate medium

J Bacteriol. 2008 Apr;190(8):3057-62. doi: 10.1128/JB.01700-07. Epub 2008 Feb 22.


The YjgF/YER057c/UK114 family of proteins is conserved across the three domains of life, yet no biochemical function has been clearly defined for any member of this family. In Salmonella enterica, a deletion of yjgF results in a requirement for isoleucine when the mutant strain is grown in glucose-serine or pyruvate medium. Feedback inhibition of IlvA is required for the curative effect of isoleucine on glucose-serine medium. On pyruvate medium, yjgF mutants are unable to synthesize enough isoleucine for growth. From this study, we conclude that the isoleucine requirement of a yjgF mutant on pyruvate is a consequence of the decreased transaminase B (IlvE) activity that has previously been characterized in these mutants.

Publication types

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

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Biosynthetic Pathways
  • Gene Deletion
  • Glucose / metabolism
  • Isoleucine / biosynthesis*
  • Models, Biological
  • Pyruvic Acid / metabolism*
  • Salmonella typhimurium / growth & development
  • Salmonella typhimurium / metabolism*
  • Serine / metabolism
  • Suppression, Genetic
  • Threonine Dehydratase / metabolism*
  • Transaminases / metabolism*


  • Bacterial Proteins
  • YjgF protein, Bacteria
  • Isoleucine
  • Serine
  • Pyruvic Acid
  • Transaminases
  • branched-chain-amino-acid transaminase
  • Threonine Dehydratase
  • Glucose