摘要
从渤海湾浅表海水中分离到150株产蛋白酶的低温菌 ,对其中5株产蛋白酶活力较高的菌株的生长特征和其所产蛋白酶的酶学性质进行了研究。这5株菌的最适生长温度都在20～25℃ ,最高生长温度都在35～40℃ ,属于典型的适冷菌。这5株菌中 ,SM9908的产酶活力最高 ,为320U/ml。这5株菌所产蛋白酶的最适酶活温度均为35～40℃。最适 pH在7.0～9.0范围内 ,为中性或碱性蛋白酶。这些蛋白酶的热稳定性普遍较低 ,SM9908所产蛋白酶的热稳定性最高 ,在50℃保温20min仍具有42.9 %的酶活。这些低温蛋白酶在洗涤剂、饲料。
protease excreted psychrotrophilic bacteria strains were isolated from the shallow sea water in Bohai Bay, and the characteristics of the growth and the properties of the excreted protease of the selected 5 strains were further studied. The optimum and highest growth temperatures were 20 25 ℃ and 35 40 ℃, respectively, which showed that the 5 strains were psychrotrophiles.Strain. SM9908 had the highest excreted protease activity, which was 320 U/ml. The optimum temperatures of the protease for casin hydrolysis were 35 40 ℃, and the optimum pH were 7.0 9.0. Therefore, the proteases belonged to neutral or alkaline protease. All these proteases had lower stability. Among of them, the protease excreted by strain SM9908 had the relatively best stability, which remained 42.9% activity after incubated at 50 ℃ for 20 minutes. These psychrotrophilic proteases have great potential in the industries of detergent, fodder, food.
出处
《海洋科学》
CAS
CSCD
北大核心
2000年第9期42-45,共4页
Marine Sciences
基金
海洋生物技术863资助项目!819 02 02号
国家自然科学基金资助项目!49790010号
关键词
渤海湾
海水
适冷菌
低温蛋白酶
Sea water, Psychrotrophilic bacteria, Psychrotrophilic proteases
