%0 Journal Article
%T Studies on Enzymatic Synthesis of Cephalexin by Immobilized Penicillin Acylase by Polyacrylonitrile Fibres<br>聚丙烯腈纤维固定化青霉素酰化酶合成头孢氨苄的研究
%A Chen Hui
%A Han Hui
%A Xu Guanzhu
%A <br>陈晖
%A 韩辉
%A 徐冠珠
%J 微生物学报
%D 2002
%I 
%X The extracellular penicillin acylase from Bacillus megaterium was immobilized by coupling to derivatives of polyacrylonitrile fibres. The apparent activity of the immobilized enzyme was about 153 U/g (wet weight). The optimal pH and temperature were 6.5 and 40 degrees C for synthesis of cephalexin by penicillin acylase, respectively. Whe the concentration of 7-ADCA was 4% and the ratio of PGME and 7-ADCA and 1:2, the average velocity of synthesis reaction was highest. The optimal supplied amount of immobilized penicillin acylase was 1.125 g/g 7-ADCA.. The apparent Michaelis constant for 7-ADCA was 0.162 mol/L and for PGME was 0.364 mol/L, Vmax was 0.0462 mol.L-1.min-1 at 30 degrees C and pH6.5. The remained activity was about 83.9% after operating 50 times.
%K Bacillus megaterium
%K Polyacrylonitrile fibres
%K Immobilized penicillin acylase<br>巨大芽孢杆菌
%K 聚丙烯腈
%K 固定化青霉素酰化酶
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=A3C6BA55AB623B90FA9104CFFC826F3C&aid=8C48386109E709F0&yid=C3ACC247184A22C1&vid=ECE8E54D6034F642&iid=CA4FD0336C81A37A&sid=228A710F49B6CE58&eid=E203FB1A272C9DD2&journal_id=0001-6209&journal_name=微生物学报&referenced_num=4&reference_num=8