title: Primary structure of macromomycin, an antitumor antibiotic protein.
abstract: The antitumor protein macromomycin is a single chain polypeptide of 112 amino acid residues cross-linked by two intramolecular disulfide bonds. The protein was reduced and S-alkylated with 2-mercaptoethanol in 8 M urea followed by treatment with iodoacetic acid. Tryptic digestion of tetra-S-carboxymethyl macromomycin gave four tryptic peptides which were fractionated by gel permeation on Sephadex G-50. The amino acid sequence of the tryptic peptides and the overlap sequences were determined by a combination of automated Edman degradation analysis, gas chromatographic mass spectrometry, and fast atom bombardment mass spectrometry. A comparison of the structures of macromomycin, actinoxanthin, and neocarzinostatin suggests that they belong to a family of related proteins.
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents; D000903:Antibiotics, Antineoplastic; D004220:Disulfides / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D013058:Mass Spectrometry; D010446:Peptide Fragments / Q000032:analysis; D010455:Peptides; D014357:Trypsin
chemical_list: D000900:Anti-Bacterial Agents; D000903:Antibiotics, Antineoplastic; D004220:Disulfides; D010446:Peptide Fragments; D010455:Peptides; C001666:auromomycin; D014357:Trypsin