An active site-tyrosine-containing heptapeptide from D-amino acid oxidase

J Biol Chem. 1980 Jul 10;255(13):6044-6.


The flavoenzyme D-amino acid oxidase (Eo) is rapidly chlorinated by N-chloro-D-leucine (Rudie, N.G., Porter, D.J.T., and Bright, H.J. (1980) J. Biol. Chem. 255, 498-508). We have carried out chymotryptic digestion of E0-36Cl2 and find that all of the radiolabel is located in a heptapeptide having [3.5-36Cl2]chlorotyrosine as the COOH-terminal residue. This heptapeptide, having the sequence -Asp-Leu-Glu-Arg-Gly-Ile-Tyr-, is located within a larger fragment obtained previously from cyanogen bromide cleavage of E0. These results demonstrate that the target for chlorination in E0 must be a single tyrosine residue and provide, when taken together with previous findings, the first clear evidence for the identity and location of an active site residue in the polypeptide chain of D-amino oxidase.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Amino Acids / analysis
  • Binding Sites
  • Chlorine / metabolism
  • Chymotrypsin / metabolism
  • D-Amino-Acid Oxidase / analysis*
  • D-Amino-Acid Oxidase / metabolism
  • Peptides / analysis*
  • Tyrosine / analysis*


  • Amino Acids
  • Peptides
  • Tyrosine
  • Chlorine
  • D-Amino-Acid Oxidase
  • Chymotrypsin