摘要
为了给酶的应用提供理论依据,采用Folin-酚法测定蛋白酶活性,通过单一变量控制对KN1菌株的蛋白酶酶学特性和发酵条件进行研究。该酶的最适作用温度为75℃,最适作用pH7.5,Cu^(2+)对酶活有促进作用;EDTA对酶活有明显的抑制作用,而PMSF对酶活的抑制作用小,推测KN1菌株产生的是一种金属蛋白酶;经SDS处理后KN1的蛋白酶仍能保持较高的活性。KN1菌株的蛋白酶的最佳发酵条件为37℃培养4天,最佳碳源为玉米粉,最佳氮源为豆饼粉。KN1菌株的蛋白酶是一种耐高温中性蛋白酶,最适作用温度达到75℃,在最适合条件下,酶活性可达1498.84U/mL,具有良好的应用前景。
In order to provide theoretical basis for application of the thermophilic neutral protease,the Folin-phenol method had been used to detect the activity of the protease.The enzyme characteristics and the fermentation conditions were determined by the single factor control experiment.This enzyme＇s optimal acting temperature and pH value were 75℃and 7.5 respectively.Cu～（2＋） could activate the enzyme.EDTA has the obvious inhibition on the enzyme,but PMSF had a little inhibition on the enzyme.The protease was postulated to a metal protease.After treating with SDS,the protease of KN1 remained high activity.The KN1 strain＇s best fermentation conditions were cultured under 37℃for 4 days,the best carbon resource was the corn-starch and the best nitrogen resource was bean powder.The protease produced by KN1 strain was a kind of thermophilic neutral protease and its optimal temperature was 75℃,and under the proper condition,the activity of the protease could reach as high as 1498.84 U/mL,and the thermophilic neutral protease of KN1 would have a good application in the future.
出处
《中国农学通报》
CSCD
北大核心
2011年第30期177-181,共5页
Chinese Agricultural Science Bulletin
基金
北京教委项目"酵母拮抗菌抗菌机制研究及其遗传改良"(KM201110020003)
关键词
耐热中性蛋白酶
蛋白酶活性
酶学性质
发酵条件
thermophilic neutral protease
protease activity
enzyme characteristic
fermentation condition
