Fig. 2From: High level expression and biochemical characterization of an alkaline serine protease from Geobacillus stearothermophilus to prepare antihypertensive whey protein hydrolysateSDS-PAGE analysis of GsProS8 before and after purification. Lane M, the protein marker; lane 1, the crude proteins; lane 2, the proteins purified by ammonium sulphate precipitation; lane 3, the proteins purified by SPFF treatment; lane 4, the proteins purified by QSFF treatment; lane 5, the zymogram of the protease. The full-length gel was presented in Fig. S3 and Fig. S4Back to article page