黑曲霉碱性蛋白酶CpyC的生化特征解析  

Biochemical characterization of alkaline peptidase CpyC from Aspergillus niger

作　　者：程磊 王正祥[1,2] CHENG Lei;WANG Zhengxiang(College of Biotechnology,Tianjin University of Science and Technology,Tianjin 300457,China;Key Lab of Industrial Microbiology of Tianjin Municipality,Tianjin 300457,China)

机构地区：[1]天津科技大学生物工程学院,天津300457 [2]天津市工业微生物重点实验室,天津300457

出　　处：《食品与发酵工业》2024年第23期1-6,共6页Food and Fermentation Industries

基　　金：天津市杰出人才计划项目(JC20200309);国家重点研发计划政府间国际科技创新合作重点专项项目(2018YFE0100400)。

摘　　要：该文对一种黑曲霉来源的蛋白酶CpyC进行了生化特征解析。该酶在结构与组成上具有丝氨酸蛋白水解酶SB家族特征性催化活性中心,由Asp188、His226和Ser381氨基酸残基组成,序列特征接近丝氨酸蛋白水解酶SB家族S08类,但与现有家族成员分类特征并不完全相同。重组CpyC的最适作用温度和pH值分别为50℃和8.0,Ca^(2+)和Co^(2+)对其分别具有最强的激活作用和抑制作用,丝氨酸蛋白酶特异性抑制剂苯甲基磺酰氟对其具有较强抑制作用,可见,黑曲霉蛋白酶CpyC是一种碱性丝氨酸蛋白酶。CpyC水解大豆分离蛋白结果显示,该酶具有水解蛋白质为多肽和寡肽的活性特征,在蛋白质生物加工中可能具有潜在应用价值。A proteolytic enzyme,CpyC,from Aspergillus niger was biochemically characterized.It contained a typical catalytic active site belonging to that of serine peptidase SB clan,with corresponding conserved amino acid residues Asp188,His226,and Ser381.Its conserved sequence or regions were similar to that of S08 class of the serine peptidase SB family,however,not completely identical to the existing family members classification features.The purified recombinant CpyC showed its maximum activity at 50℃and pH 8.0.The metal ion,Ca^(2+),showed the strongest activation effects on CpyC while Co^(2+)had the strongest inhibition effects.Its activity was strongly inhibited by phenylmethylsulfonyl fluoride,a specific serine protease inhibitor.The results suggested that protease CpyC from A.niger is an alkaline serine peptidase.CpyC could hydrolyze soybean protein isolate effectively and formed the main hydrolytes with polypeptide and oligopeptide,promoting its potential applications in protein bioprocessing.

关 键 词：碱性丝氨酸蛋白酶 黑曲霉 克隆与表达 生化特征 蛋白质水解 

分 类 号：Q55[生物学—生物化学]