Sites of modification of human angiogenin by bromoacetate at pH 5.5.
Human angiogenin is inactivated by treatment with bromoacetate at pH 5.5. Use of [14C]bromoacetate and tryptic peptide mapping have identified the sites of carboxymethylation as His-13 and His-114, with His-114 reacting approximately 1.5-fold more rapidly than His-13. At later stages in the reaction, both His-13 and -114 become modified with His-114 in part forming a bis derivative. Comparison with carboxymethylhistidine derivatives of known structure obtained from bovine pancreatic ribonuclease A indicates that the reaction order is N-1 of His-114 greater than N-3 of His-13 greater than N-3 of His-114.
Shapiro
R
R
Center for Biochemical and Biophysical Sciences and Medicine, Harvard Medical School, Boston, MA 02115.
Strydom
D J
DJ
Weremowicz
S
S
Vallee
B L
BL
D000085:Acetates / Q000378:metabolism / Q000494:pharmacology*; D000596:Amino Acids / Q000032:analysis; D043925:Angiogenesis Inducing Agents / Q000378:metabolism*; D001665:Binding Sites; D002851:Chromatography, High Pressure Liquid; D006133:Growth Substances / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D009363:Neoplasm Proteins / Q000378:metabolism*; D010446:Peptide Fragments / Q000302:isolation & purification; D011485:Protein Binding; D012259:Ribonuclease, Pancreatic; D014357:Trypsin
D000085:Acetates; D000596:Amino Acids; D043925:Angiogenesis Inducing Agents; D006133:Growth Substances; D009363:Neoplasm Proteins; D010446:Peptide Fragments; C016274:bromoacetate; C046366:angiogenin; D012259:Ribonuclease, Pancreatic; D014357:Trypsin