摘要
从海南土壤中筛选得到一株高产蛋白酶的菌株,并对其进行菌种鉴定、产蛋白酶发酵条件优化及蛋白酶分子质量测定。经筛选,得到一株高产蛋白酶的菌株,编号为CAUH83,蛋白酶活力达到126U/mL。通过形态观察、生理生化试验及16SrDNA序列分析,鉴定菌株CAUH83为粘质沙雷氏菌(Serratia marcescens)。通过单因素试验优化,确定该菌株产蛋白酶的最优发酵条件:大豆粉3.0%、蔗糖3.0%、初始pH6.0、培养温度30℃、培养时间48h。在此优化发酵条件下,该菌株产蛋白酶酶活力达到1932.3U/mL,较优化前提高15.3倍。通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)和酶谱分析表明该蛋白酶分子质量约51kDa。
A strain with high yield protease was isolated i^om soil sample of Hainan.The identification,fermentation conditions optimization and molecular mass of the strain were determined.After screening,a strain CAUH83 with high yield protease was obtained and the enzyme activity was 126 U/ml.Through morphological observation,physiological and biochemical tests and 16S rDNA sequence analysis,strain CAUH83 was identified as Serratia marcescens.The optimal fermentation conditions were optimized by single factor experiments as follows:soybean flour 3.0%,sucrose 3.0%,initial pH 6.0,culture temperature 30℃and time 48 h.Under the optimal conditions,the highest protease activity of the strain was 1 932.3 U/ml,which increased 15.3 times higher than that of before optimization.The molecular mass of the protease was about 51 kDa by SDS-PAGE and protease zymogram analysis.
作者
耿芳
杨绍青
闫巧娟
刘军
龚思怡
江正强
GENG Fang;YANG Shaoqing;YAN Qiaojuan;LIU Jun;GONG Siyi;JIANG Zhengqiang(College of Food Science and Nutritional Engineering,China Agricultural University,Beijing 100083,China;College of Engineering,China Agricultural University,Beijing 100083,China)
出处
《中国酿造》
CAS
北大核心
2018年第4期66-71,共6页
China Brewing
基金
国家重点研发计划(2017YFD0400200)
关键词
粘质沙雷氏菌
筛选鉴定
蛋白酶
发酵条件优化
Serratia marcescens
screening and identification
protease
fermentation conditions optimization
