FIG. 1.

SDS-PAGE analysis and Coomassie brilliant blue staining of mutant cysteine protease made by E. coli. Lanes: 1, molecular mass standards of the sizes indicated at the left; 2, purified recombinant His340Ala zymogen with His tag; 3, purified recombinant His340Ala zymogen with His tag removed with rTEV protease; 4, purified recombinant Cys192Ser zymogen with His tag; 5, purified recombinant Cys192Ser zymogen with His tag removed with rTEV protease; 6, purified recombinant Cys192Ser 28-kDa mature form.