Study On The Screening And Part Enzymetic Properties Of A Novel Collagenase-producing Strain

A novel collagenase-producing strain was screened and isolated from soil samples. The strain was identified as Bacillus licheniformis, by testing physiological-biochemical and morphologic characteristics. We called it J-4-8.Fermentation conditions for enzyme production have been established : the optimum conditions are carbonic resource as sucrose; nitric resource as gelatin; initial pH for 7.5;culture medium volumes for 10ml in 100ml shake ;inocution for 6%;seeds age for 24h ;compositition of the medium is edible sucrose 5%, gelatin 1.2%, yeast extract 0.1%, MgSO4.7H2O 0.08%, CaCl2 0.02%, K2HPO4 .3H2O 0.1%.After fermentation in 2 liter of fermentor at 37 "C,with an aeration rate of 1:0.5-1:1 for one day, the average collagenase enzyme activity was 31U/ml of culture broth , improved 72.2% comparing with initial fermentation culture medium.The J-4-8 collagenase was concentrated from supernatant of strain culture broth. The optimum temperature and pH for it were 41@ and 7.5.It was stable in the pH range from 7 to 10 at 4@,from 7 to 9 at 30@. In addition, the collagenase is slightly stimulated in the presence of Ca2+, but is inhibited by chelator EDTA, Cu2+, Zn2+, Pb2+, Ba2+, Fe2+. Neither * PMSF nor Mg2+significantly affected enzyme activity. The results indicated the4-8 collagenase is a metalloproteinase.