Screening and analyses of the positive transformants. A: Antimicrobial activity screening of the positive transformants of Pichia pastoris GAPMP1102. 1–30: the fermentation supernatants of the different transformants of Pichia pastoris GAPMP1102; 31: the fermentation supernatant of Pichia pastoris X-33; 32: 0.5 μg ampicillin. B: Tricine-SDS-PAGE analyses of the different transformants with positive antimicrobial activities. M: A total of 5 μl of protein molecular weight marker (from top to bottom: 40, 25, 15, 10, 4.6 and 1.7 kDa); Lanes 1–7: Totals of 10 μl fermentation supernatants of different transformants of Pichia pastoris GAPMP1102. The arrow indicates rMP1102.