A further study on the proteolysis of protective proteins by microbial and venom proteases

The limited proteolysis of protective proteins resulted in the decrease of their molecular mass which was analyzed in SDS-polyacrylamide gel electrophoresis. Both Serratia and Aspergillus proteases cleaved alpha-1-antitrypsin and slightly decreased its molecular mass. In addition to the cleavage of alpha-1-antitrypsin into several smaller fragments by Crotalus venom and Staphylococcus proteases, the mutiple prolytic fragments of IgM, IgG, and alpha-2-macrogobulin was also shown in wide-ranged molecular masses after Staphylococcus proteolysis. in comparison with relatively moderate proteolysis of egg-white lysozyme by Aspergillus, Serratia or Rizopus protease, or by Crotalus venom, the strong proteolysis of both recombinant lysozyme by Heloderma venom and egg-white lysozyme by Bacillus protease were noted. However, Androctonus venom did not significantly cleave alpha-1-antitrypsin.