Alkylation of isocitrate lyase from Escherichia coli by 3-bromopyruvate

Arch Biochem Biophys. 1990 May 1;278(2):373-80. doi: 10.1016/0003-9861(90)90273-2.


The inactivation of tetrameric isocitrate lyase from Escherichia coli by 3-bromopyruvate, exhibiting saturation kinetics, is accompanied by the loss of one sulfhydryl per subunit. The substrates glyoxylate and isocitrate protect against inactivation whereas the substrate succinate does not. The modification by 3-bromopyruvate (equimolar to subunits) imparts striking resistance to digestion of isocitrate lyase by trypsin, chymotrypsin, and V8 protease as well as a major decrease in the intensity of tryptophan fluorescence. After alkylation, the sequence Gly-His-Met-Gly-Gly-Lys is found following the modified Cys residue in the tryptic peptide representing positions 196-201. Thus Cys195 is alkylated by 3-bromopyruvate.

Publication types

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

MeSH terms

  • Affinity Labels*
  • Alkylation
  • Amino Acid Sequence
  • Enzyme Activation / drug effects
  • Escherichia coli / drug effects
  • Escherichia coli / enzymology*
  • Glyoxylates / pharmacology*
  • Isocitrate Lyase / metabolism*
  • Kinetics
  • Molecular Sequence Data
  • Oxo-Acid-Lyases / metabolism*
  • Pyruvates / pharmacology*
  • Substrate Specificity


  • Affinity Labels
  • Glyoxylates
  • Pyruvates
  • bromopyruvate
  • Oxo-Acid-Lyases
  • Isocitrate Lyase