High-Yield Soluble Expression and Simple Purification of the Antimicrobial Peptide OG2 Using the Intein System in Escherichia coli

Figure 3

Purification, and on-column cleavage of the fusion proteins. OG2-intein2 was purified using a 1 mL chitin column and cleaved by incubation with 40 mM DTT for 24 h (a) or 100 mM DTT for 24 h (b). Both the recovered insoluble (c) and soluble intein1-OG2 (d) were purified using a 1 mL chitin column, and cleavage was induced by shifting the pH from 8 to 6 and changing the temperature from 4°C to 25°C. lane M, SeeBlue Plus2 Pre-Stained Standard (kDa); lane SP, soluble protein; lane P, released OG2 (P1 and P2 were two fractions of 0.6 mL each); lane F, proteins eluted from the chitin column with 2% SDS (F1 and F2 were two fractions of 0.6 mL each); lane rIB, recovered inclusion body.