Amino terminal amino acid sequence of macromomycin, a protein antitumor antibiotic

Forty-five amino acids at the amino terminus of macromomycin, a protein antitumor antibiotic, have the following sequence: Ala-Pro-Gly-Val-Thr-Val-Thr-Pro-Ala-Thr-Gly-Leu-Ser- Asn-Gly-Glu-Thr-Val-Thr-Val-Ser-Ala-Thr-Gly-Leu-Thr- Pro-Gly-Thr-Val-Tyr-His-Gly-Glu-Ser-Ala-Val-Ala-Glu- Pro-Gly-Val-Ile-Gly-Pro- ... Of the first 31 residues in this sequence 16 are homologous with the amino terminal sequence in neocarzinostatin, a protein antitumor antibiotic which also degrades DNA. Because of this conservation of structure, this region of the molecule may be involved in the mechanism of action of these proteins.