Collagens definition

Synonyms Acid chlorides, soya, reaction prods, with protein hydrolysates, sodium salts Sodium soya hydrolyzed animal protein Sodium soya hydrolyzed collagen Definition Sodium salt of the condensation prod, of soya acid chloride and hydrolyzed collagen... 

Synonyms Soluble animal collagen Soluble native collagen Definition Nonhydrolyzed, native protein derived from connective tissue of young animals consists of a mixt. of precursors of mature collagen Properties M.w. 285,000... 

The 5 N enrichment in dentine collagen relative to bone collagen in species with definite tooth growth is observed in samples from Marillac, Kent s Cavern, Aldene and Mialet caves (Fig. 4.10). The highest 8 N values are measured for deciduous teeth in fossil samples (Bocherens et al. 1994 Fizet et al. 1995). No enrichment is observed between dentine and bone collagen in horses (Bocherens et al. 1995b Fizet et al. 1995). 

Resilin and elastin, unlike other structural proteins, fulfill both definitions of an elastic material. Colloquially speaking, resilin and elastin are stretchy or flexible. They also fulfill the strict definition of an elastic material, i.e., the ability to deform in proportion to the magnitude of an applied stress without a loss of energy, and the recovery of the material to its original state when that stress is removed. Resilin and elastin are alone in the category of structural proteins (e.g., collagen, silk, etc.) in that they have the correct blend of physical properties that allow the proteins to fulfill both definitions of elasticity. Both proteins have high extensibility and combine that property with remarkable resilience [208]. 

In other studies, mast cells have been shown to be abundant in the marrow of osteoporotic patients, and heparin, which is contained within the secretory granules of connective tissue (peritoneal)-type mast cells, has been shown to enhance bone resorption and to inhibit bone-cell replication and collagen synthesis in vitro [130]. Moreover, heparin is known to bind growth factors such as fibroblast growth factor and may therefore be important in limiting their availability [134], Taken together, these various studies suggest a possible involvement of mast cells in the homeostasis of bone, but much more work is needed before any definitive conclusions can be drawn. 

After due consideration of the control experiments carried out in the studies on collagen and gelatin and of the fact that no 3-aspartyl linkages have been reported, it seems unlikely that any a —> 7 conversion has occurred. In the case of other proteins it also seems unlikely but, in view of the fairly low values obtained and the small but significant value given by poly-a-glutamic acid by the method of Haurowitz et al. (1957), confirmatory experiments using methods similar to those of Franzblau (1962) and Franzblau et al. (1963) are necessary before any definite conclusions can be drawn. 

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