摘要
报道了用以环氧乙烷为活性基的多孔颗粒状载体 (Eupergit C)制备固定由巨大芽孢杆菌 (B .megaterium)产生的青霉素酰化酶的研究。用己二胺 ,赖氨酸对载体进行化学修饰后制备固定化酶 ,获得了较好的固定结果。用未修饰的载体制备固定化酶 ,经 2 4h固定反应 ,酶活力达 1 76 5IU/g (wet) ,酶活力总收率达 5 3 7%,酶蛋白的固定量为 1 9 7mg/g(dry) ,酶蛋白的固定效率达 87 5 %。游离酶的酶浓度对制备固定化酶的活力无显著影响。当加酶量从 3 1 2IU/g (dry)上升到 6 2 5 0IU/g (dry)时 ,固定化酶活力从 89IU/g (wet)上升到 475IU/g (wet) ,总收率和固定化效率分别从 99%和 99%下降到 2 6 5 %和 3 2 5 %,酶蛋白的固定量从 6 9mg/g (dry)上升到 1 1 2mg/g (dry) ,酶蛋白的固定效率从 99%下降致80 5 %。以酶活力为 1 5 5IU/g (wet) ,酶蛋白固定量为 2 2mg/g (dry)的固定化酶水解青霉素G钾盐 ,经过 2 0批循环水解后 ,剩余酶活力为 92 5 %。
Penicillin Acylase from B. megaterium was immobilized on the porous bead carriers based on methacrylate, N,N-methelene-bis-methacrymide, glycidyl methacrylate, Allyl ether copolymers (Eupergit-c) either directly or after chemical modification with 1.6-deaminohexane and L-Lysine. Directly binding with oxirane groups, the most efficient immobilization results were achieved. The immobilization yield was markedly influenced by the ratio of amount of free enzyme to the weight of the carrier. The specific activities of 89 up to 475IU/g (wet) and binding protein of 6.9 to 112 mg/g (dry) were obtained when the free enzyme added to the immobilization solution was from 323IU/g (dry) up to 6250IU/g (dry). The residual activity of immobilized PGA in a recycling system at the 20th was about 92.5% of the initial value.
出处
《微生物学通报》
CAS
CSCD
北大核心
2002年第3期24-28,共5页
Microbiology China
基金
国家科技攻关项目 (No. 85 72 2 0 3 0 5 )
