Abstract

In this study, a metalloproteinase gene from Planococcus halotolerans SCU63 was cloned and expressed in Bacillus sp. SCK6. LB broth medium was used as the initial medium and for a series of fermentation optimisations. The most suitable medium components were as follows (g/l): yeast extract powder (20), casein (13), tryptone (7), NaCl (10), urea (8). When the inoculation amount was 2%, the filling amount was 100mL, the culture time was 37°C, and the pH was 7.0 for 40 hours the protease production reached the highest. The enzyme activity was completely inhibited by EDTA. Surfactants, such as Tween 20, Tween 80, and TritonX-100, could improve the enzyme activity, while SDS could inhibit the enzyme activity. Under protease action, goatskin can be completely depilated at 37°C and 28 hours. Compared with the conventional chemical dehairing, the enzymatic dehairing opened up the goatskin elastic fibre without any hair root in the hair follicle, and the skin was of high quality.