Shrinkage temperature collagen

The shrinkage temperature of collagen is very much affected by interaction with various small molecules, including electrolytes and nonelectrolytes, acids and bases, tanning agents, etc., and much interesting ex-... 

In particular, acetylation experiments seemed to lend strong support. Gustavson (1954) found that complete iV-acetylation of bovine collagen does not affect the thermal shrinkage temperature of the fibers. On the other hand, combined iV- and 0-acetylation (blocking both amino and hydroxy groups) lowered T, by approximately 20°C. 

To investigate this idea, Esipova (1957) and Doty and Nishihara (1958) examined the temperature at which solutions of various types of collagen were transformed to gelatin, and compared these measurements of T with thermal shrinkage temperatures obtained by Gustavson and others. 

Gustavson (1962), recalling that the shrinkage temperature of collagen is unaltered by complete acetylation or deamination, points out that the cross-links in collagen cannot involve the e-amino groups of lysine and hydroxylysine. 

Shrinkage temperatures were determined as an indicator of the de-naturation temperature of the films. In all cases, crosslinking greatly increased shrinkage temperatures for each preparation. Thus, crosslinking stabilizes collagen molecules and retards denaturation (Table II). 

Judge, M.D. and Aberle, E.D., 1982. Effect of chronological age and postmortem aging on thermal shrinkage temperature of bovine intramuscular collagen. Journal of Animal Science 54 68-71. 

Similar arguments relative to the importance of hydrogen bonding in collagen fibrillar structure are also derived from a comparison of the shrinkage temperatures and compositions of mammalian and fish skin collagens. The latter, which possesses (see Section II, 5) fewer hydrox-ylic side chains than does the former, also has less hydrothermal stability (92). 

At first it was assumed that the combination GLY-PRO-HYPRO was of primary importance for the stability of collagen. In that way, the intramolecular bond between the carboxyl group of glycine and the hydroxyl group of hydroxyproline would be responsible for the stability. From measurements of the heat of denaturation and of the shrinkage temperature of collagen, however, one... 

Table 8. Dependence between imino add content and the shrinkage temperature of collagen [C3]...

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