摘要
目的:对来自裙带菜的1株产低温碱性蛋白酶内生菌株QD-1进行菌种鉴定,产酶条件和粗酶性质研究。方法:选取菌株性状优良、产蛋白酶活力较高的菌株QD-1,对其进行形态学及分子生物学16S rDNA鉴定,并研究其最适发酵条件。考察了碳源、氮源、发酵时间、培养温度、起始pH值等因素对菌株产蛋白酶的影响,并对其酶学性质进行研究。结果:经鉴定该菌株为芽孢杆菌属,命名为Bacillus sp.QD-1;该菌株在以蔗糖为碳源,蛋白胨为氮源,培养基初始pH 9.0,培养温度25℃,接种量10%的条件下150 r/min振荡培养48 h,所产蛋白酶活性最高达995 U/m L。该蛋白酶的最适作用温度20℃,最适作用pH 9.0,Mn^(2+)对该酶有较强的激活作用,Zn^(2+),EDTA和PMSF对该酶有抑制作用。结论 :从裙带菜内生菌QD-1发酵液中获得的蛋白酶是一种酶活较高的低温碱性蛋白酶。
The strains QD-1 producing low-temperature alkaline protease from wakame and fermentation conditions and enzymatic properties have been studied in this paper.Aim to develop new ways of high yield of protease.The strain QD-1 was identified on the morphological and 16s rDNA characteristic,and its optimum fermentation conditions were studied.The parameter of carbon source,nitrogen source,fermentation time,culture temperature and initial pH value were obtained.The results showed the strain QD-1 belonged to Bacillus according to physiological and biochemical analysis method combined with 16s rDNA sequence,named as Bacillus sp.QD-1.The optimum fermentation condition were sucrose as carbon source,peptone as nitrogen source,medium initial pH 9.0,10% inoculated quantity at 25 ℃ for 48 h,150 r/min.The protease activity reached 995 U/mL.Enzymology properties was studied further,the optimum temperature and pH value is 20 ℃ and 9.0,respectively,Mn2＋ has strong effect on the enzyme activation,while Zn2＋,EDTA and PMSF have an inhibitory effect on the enzyme.
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2017年第2期85-91,共7页
Journal of Chinese Institute Of Food Science and Technology
基金
国家级大学生创新创业训练计划项目(201410435027)
关键词
低温碱性蛋白酶
菌株
鉴定
优化
酶学性质
low-temperature alkaline protease
strain
identification
optimize
enzymatic properties
