Figure 3.

Prokaryotically expressed ChiIV3 inhibited the growth of P. capsici culturing in V8 medium. (A) SDS-PAGE assay was performed to confirm the expression level of ChiIV3 in Escherichia coli cells (BL21). The SDS-PAGE gel was stained with Coomassie Brilliant Blue (CBB) and scanned by a scanner. M, protein ladder marker; 1, pET32a-ChiIV3; 2, pET32a; 3, purified ChiIV3 protein. Asterisks represent the prokaryotically expressed ChiIV3 protein; (B) Trypan blue staining was performed to evaluate the cell death in pepper leaves triggered by purified prokaryotically expressed ChIV3 protein. Red and green circles indicate full and no cell death, respectively; (C) The purified prokaryotically expressed ChiIV3 suppressed the growth of P. capsici culturing in V8 medium. The P. capsici was first cultured in V8 medium, followed by supplemented with 500 ng prokaryotically expressed ChiIV3, and the OD₅₉₅ of P. capsici mycelia was measured at different time-points after treatment. Values are means ± SD (n = 6). Hpt, hours post treatment. Different letters indicate significant differences determined by Fisher’s protected LSD test (p < 0.05).