Figure 4

Expression and antimicrobial activity determination of rDrLysC and rDrLysG1. (A) Expression and purification of rDrLysC. M, protein marker; 1, induced bacterial lysate of pET-DrLysC/BL21; 2, residue of induced bacteria lysate of pET-DrLysC/BL21 after purification; 3, purified rDrLysC. (B) Expression and purification of rDrLysG1. M, protein marker; 1, induced bacterial lysate of pET-DrLysG1/BL21; 2, residue of induced bacteria lysate of pET-DrLysG1/BL21 after purification; 3, purified rDrLysG1. (C) Determination of the antimicrobial activity of the purified rDrLysC and rDrLysG1 against V. vulnificus. Relative antibacterial activity of the purified rDrLysC and rDrLysG1 were calculated using normal cultured V. vulnificus as control, and all samples were tested in triplicates. ** indicates highly significant differences. (D) Inhibition zones of the purified rDrLysC and rDrLysG1 against V. vulnificus strain FJ03-X2. The sterile filter paper containing 10 ?g of rDrLysC or rDrLysG1, respectively, was evenly pasted on the plate, and filter paper containing sterile water was used as control. The plates were incubated at 28 °C overnight, then the inhibition zone was observed and photographed.