氨基树脂固定化S-腺苷甲硫氨酸合成酶的研究  

Study on Immobilization of S-Adenosylmethionine Synthetase on Amino Resin

作　　者：尹春丽[1] 曹珊珊[2] 许乐[2] 陶贵荣[1] 牛卫宁[2] 

机构地区：[1]西安文理学院生命科学系,陕西西安710065 [2]西北工业大学生命学院,陕西西安710072

出　　处：《化学与生物工程》2014年第9期17-20,共4页Chemistry & Bioengineering

基　　金：国家自然科学基金资助项目(20802057);陕西省科技攻关计划项目(2014K10-13);陕西省自然科学基金资助项目(2014JQ2063)

摘　　要：以氨基树脂为载体对S-腺苷甲硫氨酸（SAM）合成酶进行固定化,优化了酶的固定化条件并对固定化酶的性质进行了研究。优化的固定化条件为：戊二醛体积分数5%、SAM合成酶添加量20mg·g-1、固定化时间5h。所制备的固定化SAM合成酶的酶活力为476.8U·g-1,酶活力回收率为74.5%。与游离SAM合成酶相比,固定化SAM合成酶的稳定性大幅提高,在50℃孵育5h酶活力仍保留61.2%,而游离SAM合成酶则完全失活;在pH值为6.0-6.5、8.0-9.5的缓冲溶液中,固定化SAM合成酶也更加稳定;固定化SAM合成酶连续催化反应10批次,酶活力保留86.3%;固定化SAM合成酶在4℃储存30d,酶活力保留81.4%。固定化SAM合成酶米氏常数KATPm=0.14mmol·L-1,KLm-Met=0.28mmol·L-1。S-Adenosylmethionine（SAM）synthetase was immobilized on amino resin.The optimal immobilization conditions and the properties of the immobilized enzyme were investigated.The optimal immobilization conditions were as follows：the volume fraction of glutaraldehyde was 5%,the dosage of SAM synthetase was 20mg·g-1,the immobilization time was 5h.Under these conditions,the activity of the immobilized SAM synthetase was 476.8U·g-1 with the activity recovery rate of 74.5%.Additionally,compared with the free SAM synthetase,the stability of immobilized SAM synthetase was improved significantly.After incubation at 50 ℃for 5h,the immobilized SAM synthetase maintained 61.2% of the original activity while the free SAM synthetase was completely inactivated.The stability of immobilized SAM synthetase in buffer solution at pH value6.0-6.5,8.0-9.5was also improved.The immobilized SAM synthetase remained 86.3% activity after ten times repeated operations.Moreover,the immobilized SAM synthetase maintained 81.4%of the original activity when it was stored at 4℃for 30 d.The Michaelis constant of the immobilized SAM synthetase was 0.14mmol·L-1（KATPm）and 0.28mmol·L-1（KLm-Met）.

关 键 词：S-腺苷甲硫氨酸合成酶 氨基树脂 固定化酶 酶学性质 

分 类 号：Q814.2[生物学—生物工程]