Purification papain

Proteolytic enzyme from the latex of Carica papaya with an approximate molecular weight of 27000. It is differentiated from papain in electrophoresis behavior, in solubility and in substrate specifity. Isolation by acidify of papaya-latex with HCl, salting out with NaCl and following chromatographic purification. The formulation contains L-cysteine as reducing agent. 

The interest in papain increased enormously after the publication by Kimmel and Smith D ] of a modification of the purification procedure of Balls and Lineweaver [5j. This modification permitted the isolation of pure papain from papaya dried latex and was used for many years as the standard method for the production of papain. The crystalline papain of Kimmel and Smith consists of three components active papain, reversibly oxidized papain, and irreversibly oxidized papain. Reversibly oxidized papain can be converted into active papain by reduction of the active-site thiol by low molecular weight thiols [10], sodium borohydride [11], or CN [12]. In active papain, the Cys-25, which is essential far catalytic activity, is present in a reduced form, while in reversibly oxidized papain the Cvs-25 forms a mixed disulfide with cysteine. Drenth et al. reported that in irreversibly oxidized papain the Cys-25 has been oxidized to the sulfuric acid... 

When this purification procedure was applied to spray-dried latex, the papain was often contaminated with chymopapain [14]. 

Affinity purification of the novel cysteine proteinase papaya proteinase IV and papain fiom papaya latex. Biochan. J. 261 469 (1989). 

D. J. Buttle, A. A. Kembhavi, S. Sharp, R. E. Shute, D. H. Rich, and A. J. Barrett. Affinity purification of the novel cysteine proteinase papaya proteinase IV and papain from papaya latex. Biochem. J. 267 469 (1989). 

Production and Purification of Anti-TPT Fab (ATF). ATF was prepared by papain digestion of ATI. Briefly, ATI at a concentration of 5mg/mL in sodium acetate buffer (pH 5.5) was incubated in 37°C water in the presence of papain, cysteine, and ethylene diamine tetraacetic acid (EDTA) for 6h. The reaction was stopped by the addition of incubation of 305-mg iodoacetamide, and subsequent... 

Uygun DA, Akduman B, Uygun M, Akgdi S, Denizli A (2012) Purification of papain using reactive green 5 attached supermacroporous monolithic cryogel. Appl Biochem Biotechnol 167 552-563... 

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