title: In vivo NH2-terminal acetylation of Sindbis virus proteins.
abstract: The in vivo incorporation of exogenous radioactive acetate into two proteins of Sindbis virus, the capsid protein and PE2, is described. Under appropriate labeling conditions, 40-50% of the label in the capsid protein is found in an N-acetyl group which constitutes the NH2-terminal modification of this blocked protein. The incorporated radiolabeled acetate was useful in the purification and analysis of peptides derived from the NH2-terminus of the capsid protein, and from these peptides the NH2-terminal sequence of the protein was determined to be N-acetyl-Met-Asx-, with the asx group most likely asparagine. The analysis of a peptide derived from the NH2-terminus of PE2 and containing 45% of the acetate-derived label in this protein leads us to conclude that at least a significant fraction of PE2 is also blocked by N-acetylation.
mesh_terms: D000085:Acetates / Q000378:metabolism; D019342:Acetic Acid; D000107:Acetylation; D002213:Capsid / Q000378:metabolism; D002918:Chymotrypsin; D010446:Peptide Fragments / Q000032:analysis; D010447:Peptide Hydrolases; D012845:Sindbis Virus / Q000378:metabolism*; D014316:Tritium; D014759:Viral Envelope Proteins; D014764:Viral Proteins / Q000378:metabolism*
chemical_list: D000085:Acetates; D010446:Peptide Fragments; D014759:Viral Envelope Proteins; D014764:Viral Proteins; D014316:Tritium; D010447:Peptide Hydrolases; D002918:Chymotrypsin; D019342:Acetic Acid