海洋低温溶菌酶的制备及酶学性质

对一株海洋杆菌产低温溶菌酶的分离纯化及理化性质进行了研究。20℃下将菌株在含有葡萄糖、酵母膏、胰蛋白胨的标准海水培养基中震荡培养40h。获得活性大约为150U/ml的溶菌酶上清液。上清液经SMB-20生物型错流超滤系统浓缩、透析及CM-Sepharose-FF阳离子交换层析（

Studies on preparation and characteristic of the marine low temperature lysozyme

The study on the physical and chemical properties and purification of low-temperature lysozyme of a marine bacterium is conducted.The strain is cultured at 20℃ for 40h on a shaker in the medium consisting of glucose, yeast extract, tryptone and artificial seawater. The supernatant of the lysozyme with activity about 150U/ml is acquired. The supernatant is purified by the procedures of lyperfiltration technology, dialyzing method, CM-Sepharose-FF positive ion column chromatography and perfusion chromatography. The enzyme electrophoreticly purified is obtained. The result shows that the enzyme consists of 143 amino acids, its molecular weight being 16KD, isoeleotric point 9.28, Km value 72μg/ml.The optimum pH of the lysozyme reacting to Micrococcus lysodleikticus is 4.5 to 8.0, the optimum temperature ranges from 5℃to 50℃. The lysozyme remains the activity of 55% at 5℃.It has certain anti-oxidation stability. The lysozyme is a typical low-temperature enzyme and can keep high activity at low-temperature. The lysozyme has broad-spectrum antibiotic reaction, which may kill gram-positive or gram-negetive germs.