摘要
为了对来自酵母细胞的天然转化酶分子进行改造,以使其适用于工业和医药领域,利用壳寡糖(COS)对酵母转化酶(YInv)的氨基进行修饰。结果发现:COS修饰后的糖链成功连接到转化酶肽链的氨基上,修饰酶(COS-Inv)的分子量比天然酶(YInv)的明显增大;COS-Inv的催化活性比YInv的提高200.3%。YInv和COS-Inv分子中的多糖含量分别为2.75和6.34 mg/mg。COS-Inv的Km值(58.92 mmol/L)比YInv的Km值(125.45 mmol/L)低得多。YInv和COS-Inv的三维荧光光谱测定结果表明,COS-Inv的荧光强度比YInv的荧光强度低得多,说明COS-Inv与YInv两者的三维分子结构有非常大的差别。由此可见,利用壳寡糖修饰酵母转化酶以改造其分子结构是提高其催化活性的有效办法。
The yeast invertase is often modified for the industrial catalysis and medicine synthesis.Herein,chitooligosaccharide(COS)was used to react with the amino groups of yeast invertase(YInv),affording a modified invertase(named COS-Inv).As a result,COS-Inv showed much larger molecular weight than the natural yeast invertase(YInv),and the saccharide contents in YInv and COS-Inv were 2.75 and 6.34 mg/mg,respectively.Compared with YInv,the catalytic activity of COS-Inv was greatly improved by 200.3%,and COS-Inv displayed much lower K m than YInv(58.92 mmol/L vs 125.45 mmol/L).According to the three-dimensional fluorescence spectra,the fluorescence intensity of COS-Inv was much lower than that of YInv,indicating the different three-dimensional molecular structures for COS-Inv and YInv.Our results demonstrated that the modification of yeast invertase by chitooligosaccharide could serve as an effective way to improve its catalytic activity.
作者
黎春怡
黄卓烈
巫光宏
何平
詹福建
LI Chunyi;HUANG Zhuolie;WU Guanghong;HE Ping;ZHAN Fujian(Department of Chemical Engineering,Maoming Polytechnic,Maoming 525000,China;College of Life Sciences,South China Agricultural University,Guangzhou 510642,China;Experimental Basis and Practical Training Center,South China Agricultural University,Guangzhou 510642,China)
出处
《生物加工过程》
CAS
2023年第6期623-631,共9页
Chinese Journal of Bioprocess Engineering
基金
国家自然科学基金(10074016)。
关键词
酵母转化酶
壳寡糖
化学修饰
酶反应动力学
yeast invertase
chitooligosaccharide
chemical modification
enzyme reaction kinetics
作者简介
黎春怡(1973-),女,广东吴川人,副教授,研究方向:生物化学工程,E-mail:mmlcy_li@126.com;黄卓烈(联系人),教授,E-mail:zhuolieh@scau.edu.cn。
