Papaya latex

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. 

Satrija, F., Nansen, P., Bjorn, H., Martini, S. and He, S. (1994). Effect of Papaya latex against Ascaris suum in naturally infected pigs . Journal of Helminthology, 68(4), 343-346. 

This enzyme [EC 3.4.22.6], also known as papaya proteinase II, is a member of the peptidase family Cl. It is the major endopeptidase of papaya (Carica papaya) latex. It has a specificity similar to that of papain. In addition, there are a number of chromatographic forms of the enzyme. 

Brocklehurst, K., Carlsson, J., Kierstan, M.P.J, and Crook, E.M., Covalent chromatography. Preparation of fully active papain from dried papaya latex, Biochem. J., 133, 573-584, 1973. 

This enzyme, which was discovered in papaya latex by Messer (10), catalyzes the conversion of glutamine and glutaminyl peptides to pyrrolidone carboxylic acid or pyrrolidone carboxylyl peptides, respectively ... 

The purification of glutamine cyclotransferase from papaya latex has been carried out by Messer and Ottesen (116). A batch procedure was used for the removal of impurities by passage of a papaya latex extract through a thin layer of carboxymethyl-Sephadex the active protein was separated by selective elution. Additional purification was achieved by chromatography on a column of carboxymethyl-Sephadex and by gel filtration on Sephadex G-100. The purified enzyme was homogeneous by the criteria of paper electrophoresis, ultracentrifugation, and gel filtration on Sephadex G-100 columns and chromatography on carboxy-methyl- or DEAE-Sephadex. The electrophoretic behavior of the enzyme indicates that it is a basic protein with an isoelectric point near... 

Note. (1) An inexpensive crude commercial product (dried papaya latex) was used the activity was not determined. Purified highly active enzyme preparations may, however, be obtained259 (e.g. Koch-Light, Sigma, etc.). 

In 198ft, Loozeet al. published a series of articles on the cysteine proteinases from papaya latex. In the first article, they described an alternative way to purify chymopapain and papaya proteinase El to homogeneity [32], In the following articles die primary structures of chymopapain [33] and papaya proteinase 2 [34] were described (Fig. ). The primary structure of chymopapain determined by Wblson et al. [35] is in perfect agreement with the results of Dubois ct al. 

Lynn [22) and POlgdr [39] detected in 1979 and 1981. respectively, that the papaya latex contained an endopeptidase with a markedly different specificity from (hose of the three previously purified enzymes. However, k look until 1989... 

El is well known that the cysteine proteinase of the papaya latex differ in their ability to hydrolyze proteins and synthetic peptides. Schechter and Beiger [67] first demonstrated that the landing regions in the active center of proteinases can be divided into different subtitles, of whidi die Sz subsite seems to be the most important in papain. 

The residues in the Sj subsite that make the most intimate contact are those of Val-133, Val-157, Ala-160, Pro-68, and iyr-67. In the four enzymes of the papaya latex, ail incite groups remain hydrophobic, wiui the exception of Pro-68, which is replaced by Olu in chymopapain and in gtycyl endopeptidase. The nonpolar character, and generally specificity, of the S2 subsite would therefore be conserved. 

Crude papaya latex, usually called papain, has found a number of industrial applications. It has been used in brewing, meat tenderization, flavor production. 

P. Sc hack. Fractionation of proteolytic enzymes of dried papaya latex. Isolation and pBriimiimy characterization of a new proteolytic enzyme. CJ . Lob. Carisberg J 67 (1967). 

K.R, Lynn. A purification and some properties of two proteases from papaya latex. Biochim. Biophys. Acta56 193 (1979). 

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

C. K. Kang and W. D. Warner. Tenderizatkm of meal with papaya latex proteases. /. FoodSci. 59 812 (1974). 

Papain Carica papaya, latex Peptides, amides, esters Carboxylic acid... 

Not only defense secondary metabolites but also defense proteins may exist as precursors. For example, papain, a cysteine proteinase that exists in papaya latex and recently found to have strong defense activity, is kept in laticifer as an inactive precursor and within 2 min after wounding, it becomes active.1 4... 

Some of the basic information on stabilizing sulfhydryl enzymes, has been responsible for their commercialization. Without the judicious use of reducing compounds throughout the processing of the papaya latex, it would not have been possible to maximize the proteolytic activity of commercial papain preparations. Examples of other studies of enzymes which have contributed to commercialization are the determination of calcium ion as a requirement for amylase stability at high temperature, the difference in properties of catalases derived from bacterial, fungal, or... 

In addition to papain, at least two other proteolytic components have been shown to be present in crude extracts of commercial papaya latex, namely, chymopapain (1,27) and papaya peptidase A (28). Since these isolated enzymes are not used commercially, they will not be considered further. 

To date, the latex of Carica papaya L. is known to contain at least four different proteolytic enzymes, namely, papain (E.C. 3.4.22.2), chymopapain (E.C. 3.4.22.6), caricain or papaya proteinase III or 2 (E.C. 3.4.22.30), and glycyl endopeptidase or papaya proteinase IV (E.C. 3.4.22.25). The importance of the latex of the unripe fruit of the tropical tree Carica papaya L. was first noted by G. C. Roy, who in 1873 published in the Calcutta Medical Journal (see Ref. 1) an article entitled The solvent action of papaya juice on the nitrogenous articles of food. The name papain was used for the first time by Wurtz and Bouchet [2] to describe partially purified cysteine proteinases from the papaya latex. They wrote, nous designerons ce ferment sous le nom de papa ine." In 1880, Wurtz postulated that papain acts in fibrin digestion by becoming bound to the fibrin [3]. This is remarkable in that Emil Fisher first described the specific association of enzyme with substrate in 1898. Since that time, many names have been used for commercial latex products, e.g., papayotin, papaoid, etc. 

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