Fig. 4

The purified recombinant protein rF2 has antifungal activity. SDS-PAGE analysis of the recombinant protein rF2 heterologously expressed in Pichia pastoris and purified using Niaffinity column (a). The antifungal activity of recombinant protein F2 (rF2) against R. cerealis (b). Lane 1: molecular weight marker; lane 2: total protein fraction from non-induced strain; lane 3: total protein fraction from the methanol-induced strain; lane 4: the recombinant protein rF2 purified by Niaffinity column; A, the negative control of 10 mmol/l Tris–HCl buffer (pH 7.5); B, the total fermentation supernatant proteins of P. pastoris before methanol induction; C, the total fermentation supernatant proteins of P. pastoris after methanol induction; D, the positive control of 10 µg of iturin A standard dissolved in 30 µl of 10 mmol/l Tris–HCl buffer (pH 7.5); E, 10 µg of the purified rF2 dissolved with 30 µl of 10 mmol/l Tris–HCl buffer (pH 7.5). An aliquot of 30 µl of each sample was added into the well, respectively