Plant proteases with excellent catalytical properties perform many functions in biological systems. Vallaris solanacea, a new plant protease has been identified and screened effectively for its caseinolytic activity. This protein activity was specifically inhibited by p-chloromercuribenzoate, which showed that it is a cysteine protease. Preliminary investigations such as effect of pH and temperature on the caseinolytic activity of crude protease were done. Stability towards temperature and pH were also evaluated. The pH and temperature activity curves and other stability studies suggested the possible presence of one proteolytic enzyme in the latex of Vallaris solanacea. In the present study, separation and purification of the cysteine protease
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Such a protease was identified in the latex of Vallaris solanacea. Further study aimed at performing preliminary investigations on protease, purification, molecular weight determination and further characterization of Vallaris solanacea derived protease solanain [29]. The latex of Vallaris solanacea has high proteolytic activity, the activity being comparable to those of other known latex proteases such as papain, ficin, bromelain, asclepain, calotropain etc. Crude latex showed a specific activity of 87.5 at pH 9.0. The pH optima observed with crude enzyme towards casein and hemoglobin as substrates was 9.0.This is comparable to other proteases, which are generally more active in the alkaline pH range [49,50].This observation suggests the possibility of existence of one component with proteolytic activity. The temperature for optimum activity was as high as 60°C and is comparable to other plant proteases. Stability studies showed that proteases may be stored in reversibly inhibited state. Resistance towards heat denaturation of the enzyme is remarkable and resembles other plant proteases [51, 52 and 53]. Preliminary studies on the protease activity of the crude latex revealed that the enzyme resemble other plant proteases in their a) requirement of a reducing agent for maximal activity; b) Inhibition by several conventional agents such as PCMB; and c) presence of an active SH group. The pH and temperature activity curves and other stability studies suggest the possible presence of one proteolytic enzyme in the latex of Vallaris solanacea. Cysteine protease isolated from Vallaris solanacea was purified to homogeneity by ammonium sulphate precipitation (between 30-50% saturation) followed by DEAE cellulose ion-exchange
Such a protease was identified in the latex of Vallaris solanacea. Further study aimed at performing preliminary investigations on protease, purification, molecular weight determination and further characterization of Vallaris solanacea derived protease solanain [29]. The latex of Vallaris solanacea has high proteolytic activity, the activity being comparable to those of other known latex proteases such as papain, ficin, bromelain, asclepain, calotropain etc. Crude latex showed a specific activity of 87.5 at pH 9.0. The pH optima observed with crude enzyme towards casein and hemoglobin as substrates was 9.0.This is comparable to other proteases, which are generally more active in the alkaline pH range [49,50].This observation suggests the possibility of existence of one component with proteolytic activity. The temperature for optimum activity was as high as 60°C and is comparable to other plant proteases. Stability studies showed that proteases may be stored in reversibly inhibited state. Resistance towards heat denaturation of the enzyme is remarkable and resembles other plant proteases [51, 52 and 53]. Preliminary studies on the protease activity of the crude latex revealed that the enzyme resemble other plant proteases in their a) requirement of a reducing agent for maximal activity; b) Inhibition by several conventional agents such as PCMB; and c) presence of an active SH group. The pH and temperature activity curves and other stability studies suggest the possible presence of one proteolytic enzyme in the latex of Vallaris solanacea. Cysteine protease isolated from Vallaris solanacea was purified to homogeneity by ammonium sulphate precipitation (between 30-50% saturation) followed by DEAE cellulose ion-exchange