Papain and

Pish protein concentrate and soy protein concentrate have been used to prepare a low phenylalanine, high tyrosine peptide for use with phenylketonuria patients (150). The process includes pepsin hydrolysis at pH 1.5 ptonase hydrolysis at pH 6.5 to Hberate aromatic amino acids gel filtration on Sephadex G-15 to remove aromatic amino acids incubation with papain and ethyl esters of L-tyrosine and L-tryptophan, ie, plastein synthesis and ultrafiltration (qv). The plastein has a bland taste and odor and does not contain free amino acids. Yields of 69.3 and 60.9% from PPG and soy protein concentrate, respectively, have been attained. 

Dermatan sulfate (condroitin sulfate B from pig skin) [54328-33-5 (Na salt)]. Purified by digestion with papain and hyaluronidase, and fractionation using aqueous EtOH. [Gifonelli and Roden Biochem Prep 12 1 1968.]... 

Structure of GFP and its chromophore. To study the chro-mophore of GFP, a sample of GFP was denatured by heating it at 90°C. It was digested with papain, and then a peptide containing the fluorophore was isolated and purified from the digested mixture. The structural study of the peptide has indicated that the chromophore of GFP is an imidazolone derivative shown below (Shimomura, 1979). This chromophore structure was confirmed later by Cody etal. (1993) in a hexapeptide isolated from GFP. It is intriguing that the structure of the GFP chromophore is a part of the structure of coelenterazine. 

Papain and four protease formulations that varied from neutral to alkaline as regards optimal pH for activity. 

N-Nitrosamines have been shown to be inhibitors of cysteine-containing enzymes. For example, dephostatin and other N-methyl-N-nitrosoanilines (1) were found to be inhibitors of the protein tyrosin phosphatases, papain and caspase [90,91]. Inhibition results from the S-nitrosation of the critical cysteine residues in the active sites of the enzymes by the nitrosamines. Compounds 6 and 7 have been found to inhibit thrombus formation in arterioles and venules of rats [92], while N-nitrosamide 9 exhibited vasodilation and mutagenicity as a result of NO release [93]. 

CA 5 Families of mostly endopeptidases (including papain and some cathepsins in family Cl, and calpains in family C2) Gin, Cys, His, Asn/Asp ... 

An antibody can be cleaved by enzymes such as papain and pepsin into different fragments (Fig. 4.2). 

Inhibitor of serine and cysteine proteases plasmin, trypsin, papain and cathepsin B Inhibitor of type 1 and type 2A protein phosphatases... 

Leh, F., and J. B. Mudd. Reaction of peroxyacetyl nitrate with cysteine, qrstine. methionine, lipoic acid, papain, and lyso me. Arch. Biochem. Biophys. 161 216-221, 1974. 

Todd, G. W. Effect of low concentrations of ozone on the enzymes catalase, peroxidase, papain and urease. Physiol. Plant. 11 457-463, 1958. 

Lowe et al. investigated the substrate selectivity of the proteases papain and chy-motrypsin using PEGA-bound combinatorial peptide hbraries (32) (Fig. 10.3) [24]. The quahtative extent of enzymatic cleavage of the resin-bound peptide in case of an accepted substrate strand was rapidly visualized by a significant reduction in the fluorescence of the beads visuahzed with a fluorescence microscope. Furthermore it was proven that substrate selectivity of the enzyme remain the same on the solid phase and in solution. 

Borio P (1953) The anthelmintic action of papain and of piperazine diphenylacetate (DPP). Minerva Farm 2(4) 141-142... 

X 10 units papain and 100 mg Accuzyme (Healthpoint), Ethezyme 830 urea per g (Rx) (Ethex), Gladase (Smith Nephew)... 

At one time, broad spectrum proteolytic enzymes (mainly papain and bromelain) were widely used to delay or minimize haze formation in beer (de Clerck, 1969). The enzymes cleaved protein chains, that when... 

Later, oxyanion holes were also discovered in other proteases, such as the cysteine protease papain, and in esterases and lipases, enzymes capable of esterification or ester hydrolysis. Interestingly, in these esterases, sometimes up to three hydrogen bond donors can be located within 3 A of the carbonyl oxygen atom, whereas such triple hydrogen bonding motifs have not yet been found in the proteases. 

Extraction with sodium phosphate-sodium citrate/ ascorbate buffer at 100°C for lOmin enzymatic digestion with papain and amylase... 

Either acid or alkaline hydrolysis can be applied, converting nicotinamide to nicotinic acid. Alkaline hydrolysis releases also the unavailable vitamers providing the estimation of the total niacin content. Acid hydrolysis, instead, is slower than alkaline hydrolysis therefore the former is usually coupled with enzymatic digestion by using takadiastase, papain, and clarase. Extraction with water and dilute sulfuric or hydrochloride acid has been applied to release the vitamers from the matrix without degrading nicotinamide [598]. 

Homogenization with HjO, glutathione, EDTA, citrate buffer, papain and takadiastase (for high starch samples) incubation over night filtration... 

Proteins free-sulfvdrvl papain and chymopapain (papaya, Carica papaya L., Violales, Ang. native to S Amwica, cultivated in Zaire, Uganda, Tanzania, and the East) and brcmelain (pineapple. Ananas comosum, Bromeliales, Ang. native to S America, cultivated in Africa) NO-releasing heme nitrqjhwin (blood-sucking Ins. Rhodnius prolixux Walker 1999). 

C—N—OH, the mercaptan because it appears in the cysteine proteases (e.g., papain) and the others because they are effective in small-molecule model systems. 

In this way Goldman et al.2-5 incorporated papain and phosphatase in collodion membranes, and other authors6-7 have done likewise with several enzymes in cellophane membranes. It is important to note the work of Suzuki8 on collagen membranes as well as the work on enzyme reactors9,10... 

The cysteinyl proteases include papain calpains I and II cathepsins , H, and L proline endopeptidase and interleukin-converting enzyme (ICE) and its homologs. The most well-studied cysteinyl protease is likely papain, and the first x-ray crystallographic structures of papain [193] and a peptide chloromethylketone inhibitor-papain complex [194] provided the first high resolution molecular maps of the active site. Pioneering studies in the discovery of papain substrate peptide-based inhibitors having P, electrophilic moieties such as aldehydes [195], ketones (e.g., fluoromethylketone, which has been determined [196] to exhibit selectivity for cysteinyl proteases versus serinyl proteases), semicarbazones, and nitriles are noteworthy since 13C-NMR spectro-... 

Additional examples of type d (Scheme 5.1) bifunctional reactants are provided by the alkaline-earth metal ion complexes of lariat ethers 8-10, bearing a sulfhydryl side arm, instead ofthe phenolic hydroxyl of a calixcrown [23,24]. Here the acyl-receiving and acyl-releasing unit, like in papain and ficin, is a sulfhydryl group. 

Verma and McCalla ( ) studied the action of pepsin, papain and a commercial fungal protease on wheat gluten. All enzymes acted effectively on dispersed gluten however, the action of different enzymes produced different types of digestion products. Depending upon desired handling characteristics of bread doughs prepared from treated wheat flour, various types of protease treatments can be selected. 

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