Papain activities

Digestalin 3/100 extract/ceUulase/glutamic acid pancreatin/pepsin/papain/activated Vortech... 

When the target enzyme is difficult to obtain, related enzymes could be used to provide insights in the design of novel ligands. For example, papain was used to design a class of potent cathepsin K inhibitors [33] spanning both sides of the papain active site. However, fine-tuning these inhibitors to produce more potent ones required the use of the crystal structure of cathepsin K itself [34],... 

Winner, S. Rubin, and A. Riklin, Photoregulation of papain activity through anchoring photochromic azo groups to the enzyme backbone, J. Am. Chem. Soc., 113, 3321-3325(1991). 

Papain active fragment 00-65 Hill and Smith (1960) ment possible... 

Analogous photoresponsive peptide and polypeptide systems are being developed the photochemical properties of poly[W -p-(phenyl-azo)benzoyl-L-a,/8-diaminopropionic acid] have been examined, and the first example of photoregulation of permeability across a membrane has been achieved by the use of a new polyvinyl/poly-peptide graft copolymer composed of a photoresponsive copolypeptide branch from /3-p-phenylazobenzyl L-asparate and /3-benzyl L-asparate attached to a poly(Bu methacrylate) backbone.Papain activity has similarly been regulated by anchoring a photo-responsive azo group to the enzyme backbone. ... 

For many years a controversy over the nature of papain activation confused the literature. Apparently cyanide, cysteine, glutathione, and... 

The descending portions of the curves for ki in Figure 26 must represent the titration of groups essential for papain activity. On the acid side of the curve, ki reaches a maximum near pH 5. The... 

Although only a part of the peptide sequence appears to be essential, it should not be supposed that the secondary structure of this protein plays no role in its activity. The fact that papain activity can be destroyed by acid, alkali, or heat, under conditions w hich do not appear to break peptide bonds, indicates that some d ree of secondaiy organization is involved in the catalytic specificity of the enzyme. 

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