Two-dimensional electrophoresis patterns of the CNBr peptides of collagen types I, II, III and V.

A two-dimensional mapping method developed for collagen chains has been applied to the CNBr-peptides of rat collagen types I, II, and III and bovine type V (AB) collagen. The method consists of isoelectric focusing in a 4% polyacrylamide gel-6 M urea-2% Pharmalyte with a pH gradient ranging 5 to 10 in the first dimension and SDS-polyacrylamide slab gel (15%) electrophoresis at pH 8.8 in the second dimension. Characteristic peptide maps were obtained for each type of alpha-chain and can be used for identification of isolated collagen chains. Application of this method to an authentic mixture of collagen types and a fraction isolated from rat skin has indicated that the method is sensitive enough to resolve collagen types with a sample as low as 40 micrograms per alpha-chain.