Collagen enzymatic hydrolysis

Reese (18) is not convinced. He argues that the first step in the enzymatic hydrolysis of other highly ordered structures such as DNA and collagen is affected by enzymes whose function it is to produce some disorder in the structures as a preliminary to hydrolysis by other enzymes. Such enzymes are highly specific for ordered molecules, and they are unable to act on the disordered structures that they produce. Thus Reese rationalizes that the first step in the hydrolysis of crystalline cellulose involves a similar type of enzyme. 

Gelatin is the product obtained from the acid, alkaline, or enzymatic hydrolysis of collagen, the chief protein component... 

The most common methods for the preparation of collagens are various extractions and precipitations or the release of protein by enzymatic hydrolysis. These methods mainly include extraction with an NaCl-phosphate buffer, acetate buffer, or acetic acid, and precipitation using various concentrations of NaCl (their usage depends on the tissue and type of collagen). 

It is not always possible to apply enzymatic hydrolysis directly to proteins as they are in the native form. Native, globular proteins (e.g., from soy, corn, almond) or fibrous insoluble proteins (e.g., collagen, keratins, elastin) are generally resistant to proteolysis this is generally explained by the compact tertiary structure of the protein that protects most of the peptide bonds. In the denatured, unfolded form the peptide bonds are exposed and available for enzymatic cleavage. As native proteins in aqueous solution are in dynamic equilibrium with a number of more or less distorted forms, part of which can be considered denatured and thereby accessible to enzyme attack, the initial break of a few peptide bonds can destabilize the protein molecule and cause irreversible unfolding in some cases (e.g., hydrolysis of egg albumin by pepsin) this mechanism allows the protease to perform the hydrolysis to a remarkable extent. More frequently, especially when covalent bonds (disulfide bonds) stabilize the native form of the protein, a preliminary partial or extended denaturation is needed to make enzymatic hydrolysis possible this is normally achieved by heating or chemical attack, or a combination of the two. 

A different chemical reaction can naturally be used. This was done independently by Oplatka and his co-workers [123] who used the contraction of collagen induced by the acid-producing enzymatic hydrolysis of esters. They are now also developing systems using ATP. This mechano-chemical field will surely know an interesting development in connection with polyelectrolytes. 

In contemporary bone from a mature animal, native type I collagen makes up approximately 90% (by weight) of the protein and can only be brought into solution by partial enzymatic digestion or add hydrolysis.9 In... 

In addition to enzymatic degradation, the collagen xmdergoes degradation by hydrolysis under the influence of temperature and/or mechanical stress. The presence... 

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