An extracellular protease from Clonostachys rosea (syn . Gliocladium roseum) was purified to SDS-PAGE homogeneity with 14-fold purification by ultrafiltration、ammonium sulfate precipetation、hydrophobic interaction chromatography and anion exchange chromatography. The molecular weight of the protease was 32 kDa as estimated by SDS-PAGE. The N-terminal sequence of first 10 amino acids was A-T-Q-S-N-A-P-W-G-L. This enzyme exhibited pH and temperature optima of 9-10 and 60 ℃, respectively, and was stable over a wide range of pH 4-10 and temperature 4-50 ℃. It did not require Ca 2+. for activity and thermal stability. Pre-incubation of enzyme with Zn 2+., Cu 2+., Hg 2+., Fe 3+. inhibited most of the enzyme activity, but Mn 2+. increased enzyme activity up to 38%. It remained stable in the presence of Tween20, H 2O 2, EDTA. The inhibition profile of the enzymes by PMSF, suggested that this purified protease belongs to the serine protease family. The protease could immobilize nematodes (Panagrellus redivirus) in bioassays and hydrolyzed proteins of the purified cuticle.
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