STUDIES ON THE DESAMIDATION OF BOVINE COLLAGEN

The most important reactive groups in collagen are amino, amido, guani dino, and carboxyl, all of which are present in comparatively large nu mbers. It is possible to modify amide groups present in the collagen o f achilles tendons and hide trimmings by desamidation (DAM). DAM cause s progressive hydrolysis of the amide groups of asparagine and glutami ne side chains of collagen, thereby resulting in the reduction of the amide content of collagen. Loss of amide brings about an increase in t he number of free carboxyl groups in the desamidated collagen, shown b y reduction in its isoionic pH. The new modified collagen, like type I bovine collagen, has high viscosity and high hydroxyproline content. The fibril formation of the modified collagen showed slight variation, and polyacrylamide gel electrophoretic analysis indicated largely alp ha components, indicating destruction of inter- and intramolecular cro sslinks. The swelling behavior of the modified collagen is significant ly higher compared to type I bovine collagen. (C) 1997 John Wiley & So ns, Inc.