Characterization of phaseolin modified by legumain
2007
Rotari, V. | Morari, D. | Stepurina, T.
The characterization of phaseolin modified by legumain is of great interest for the finding of the peculiarities that makes it susceptible to the action of other endopeptidases. Here we report the results of the investigation of the action of legumain on phaseolin that extend the previously obtained findings. These results indicate that legumain is the enzyme that triggers the degradation of phaseolin. The modifications caused by legumain makes the phaseolin molecule susceptible to the attack of CPPh. The elucidation of the mechanism by which this proteolysis is achieved is of major interest. Any proteinase is capable of splitting one to several accessible, flexible segments of a particular substrate protein, provided that these segments are situated on the surface of the protein molecules and contain peptide bonds corresponding to the proteinase specificity. If such cleavage(s) destabilize(s) the protein structure then unfolding of the substrate protein occurs leading to subsequent extensive hydrolysis. These considerations allow plausible explanations to be proposed for the differences observed in the course of proteolysis of different 7S proteins. So, the cause of the difference detected should be looked for in the peculiarities of phaseolin structure. Perhaps the determination of X-ray structure of phaseolin-L and/or phaseolin-CPPh could prove decisive in the solution of this conundrum.
显示更多 [+] 显示较少 [-]