Collagen acid-extracted

A better understanding of the structure of collagen IV molecules explains some previous observations. The occurrence of the 7 S domain and nonhelical interruptions in the molecule can explain in part the heterogeneous mixture of collagenous components isolated from basement membrane, particularly when pepsin or other proteases are used to solubilize the protein. The molecules isolated from lathyritic basement membrane by acid extraction are truncated and lack the 7 S domain presumably due to cleavage by endogenous proteases. 

Essentially similar conclusions have been reached by Grassmann et al. (1961) on the basis of an analysis of sedimentation patterns of denatured, acid-extracted calfskin collagen. They propose that the formation of the /3-component arises from cross-linking of two a components which may or may not be identical in amino acid composition, while a third component always present in small amount, the y component, represents a structure in which three a-components are cross-linked together. 

AG, Alkali-processed gelatin G, acid-extracted gelatin SC, soluble collagen IC, insoluble collagen LC, limed collagen. Time in days. 

Reconstitution of fibrils is necessary if native collagen molecules are to be obtained by acid extraction. Collagen... 

Collagen is the most abundant and ubiquitous structural protein in the body, and it may be readily purified from both animal and human tissues with an enzyme treatment and salt/acid extraction (Li 1995). Collagen has long been known to exhibit minimal inflammatory and antigenic responses (Furthmayr and Timpl 1976), and it has been approved by the U.S. Food and Drug Administration (FDA) for many types of medical applications, including wound dressings and artificial skin (Cen et al. 

Tig. 0. Chromatograms on CM cellulose of denatured soluble collagens obtained by sequential extractions of human infant skin with 1 M NaCl, 0.5 M acetic acid (two times), and 5 M guanidine hydrochloride. The column was eluted at 40 C and pH 4.8 with a salt gradient. Note that collagens ere extracted by ecid.s and guanidine which are not extracted by salt. (Courtesy Bornstein and Piez, 1964.)... 

M.p. 190-192 C. The enolic form of 3-oxo-L-gulofuranolactone. It can be prepared by synthesis from glucose, or extracted from plant sources such as rose hips, blackcurrants or citrus fruits. Easily oxidized. It is essential for the formation of collagen and intercellular material, bone and teeth, and for the healing of wounds. It is used in the treatment of scurvy. Man is one of the few mammals unable to manufacture ascorbic acid in his liver. Used as a photographic developing agent in alkaline solution. 

In addition, our results suggest that removal of hpids improves both yield characteristics and elemental characteristics. Recent work by Liden et al. (1995) suggests that the methanol-chloroform method used here is more effective than other methods, such as treatment with NaOH solution, or the maintenance of an acidic environment and ultrafiltration of products during collagen extraction. It is speculated that the presence of hpids in archaeological bone samples may interfere with the acid hydrolysis of protein during... 

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