Isolation and characterization of the cyanogen bromide peptides from the α1 and α2 chains of soluble bovine striated muscle collagen

Abstract

1. 1.The α1 and α2 chains of soluble bovine striated muscle collagen were cleaved with CNBr and the resulting peptides separated and purified by a combination of ion-exchange and molecular sieve chromatography. 2. 2.The finding of eight peptides from the α1 chain and six from the α2 chain was consistent with the methionine content of these chains. 3. 3.The amino acid compositions and molecular weights of the peptides accounted for all the amino acids and the molecular weight of the intact chains. 4. 4.Only minor variations were discernible in the amino acid composition of the CNBr peptides from soluble muscle collagen and that reported for other mammalian and avian soluble collagens. 5. 5.Similar to primate collagen, a methionine substitution in the NH 2-terminal sequences of the α1 chain resulted in the elimination of the NH 2-terminal dipeptide, α1-CBo, which is present in rat tendon and chick soluble collagen. 6. 6.The soluble muscle collagen α1 also contained a single α1-CB6 peptide rather than the α1-CB6A and α1-CB6B peptides found in chick skin and bone. 7. 7.The presence of the aldehyde form of the NH 2-terminal nonhelical peptides from the α1 and α2 chains of soluble muscle collagen suggests that lysyl residues are involved in the formation of intramolecular cross-links as has been shown for rat and chick soluble collagens.