ANALYSIS OF COLLAGEN CYANOGEN-BROMIDE PEPTIDES USING ELECTROPHORESIS IN CONTINUOUS CONCAVE GRADIENT POLYACRYLAMIDE GELS

A method of analyzing cyanogen bromide peptides obtained from human type I and III collagens using electrophoresis in sodium dodecyl sulfate-concave polyacrylamide gel slabs was evaluated. Improved recoveries of small peptides (10,000-20,000 MW) were obtained and the type III collagen peptides 3, 6, and 8, which migrate as a single band on 7.5% polyacrylamide gels, were resolved into two bands on gradient gels. A callbration factor was derived to convert the densitometry areas of the α2 CB3.5 (type I collagen marker) and the αI(III) CB8 (type III collagen marker) into approximate weight ratios of these collagens. Using this calibration factor semiquantitative estimations of the relative proportions of type I and III collagens in insoluble dermis and bone were made. Gradient gels were also suitable for the study of some aspects of peptide involvement in cross-linkages. © 1979.