摘要
采用细胞破碎,热变性除杂蛋白,有机溶剂沉淀,DEAE-Sepharose Fast Flow柱层析等方法从酵母中纯化酵母蔗糖酶,用5种化学修饰剂PMSF、SUAN、NBS、DTT、EDTA及几种金属离子对其进行化学修饰。结果表明:酶分子中的丝氨酸残基和金属离子与酶活力无关,赖氨酸残基和半胱氨酸残基对酶活力有一定贡献,但不位于酶的活性中心;而色氨酸残基是酶活性中心的必需基团。
In this study,yeast invertase（β-fructofuranoside hydrolase） was extracted and purified by cell disruption,heat denaturation,organic solvent precipitation and DEAE-Sepharose Fast Flow chromatography.Five chemical modification agents（PMSF,DTT,SUAN,NBS,EDTA） and several other metal ions were used to determine the amino acid residues involved in the active site of yeast invertase.The result indicated that serine residues and metal ions were inessential to the invertase activity while the lysine and cysteine residues were linked to the enzyme activity, which were not in the active site of the enzyme.That the indolyl ring of tryptophan residues could be modified by N-bromosuccinimide and these groups could be protected by sucrose revealed that the tryptophan residues were present at the invertase active site.
出处
《食品与生物技术学报》
CAS
CSCD
北大核心
2010年第6期901-904,共4页
Journal of Food Science and Biotechnology
基金
山东省自然科学基金项目(ZR2009DM042)
山东师范大学实验教学改革项目
山东师范大学精品课程建设项目
关键词
酵母蔗糖酶
纯化
化学修饰
yeast invertase
purification
chemical modification
