摘要
为了获得缓解泌尿系统草酸盐结石病症的酶制剂,用无载体固定化方法——交联酶聚集体(CLEAs)制备交联草酸脱羧酶聚集体。使用基因工程菌E.coli BL21(DE3)/pET32a/YvrK诱导表达制备草酸脱羧酶粗酶液,用30%的乙醇进行沉淀分离提纯,纯化倍数为2.7倍,酶活回收率91.2%;在戊二醛添加量为0.06%、pH5、牛血清白蛋白添加量0.5g/L、4℃的条件下处理该酶2h,得到交联草酸脱羧酶聚集体(oxdc-CLEAs),酶活回收率达95.4%;酶学性质研究表明,相对游离草酸脱羧酶,交联草酸脱羧酶聚集体的耐酸性、耐热性、耐胰蛋白酶降解能力均有提高。
Cross-linked oxalate decarboxylase aggregates （oxdc-CLEAs） for use as an enzyme preparation to relieve urinary oxalate stone disease were prepared by a carrier-free immobilization method. Crude enzyme solution was obtained from the induced expression of the genetically engineered strain E.coli BL21（DE3）/pET32a/YvrK, and oxalate decarboxylase was separated by adding 30% ethanol with a purification factor of 2.7 and an activity recovery of 91.2%. Cross-linked oxdc-CLEAs were further obtained after 2 h of cold treatment at 4 ℃ in the presence of 0.5 g/L bovine serum albumin （BSA） and 0.06% glutaraldehyde at pH 5, resulting in an activity recovery of 95.4%. Enzymatic characterization showed that cross-linked oxdc-CLEAs had improved tolerance to acid, heat and trypsin degradation when compared to free oxalate decarboxylase.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2013年第1期215-219,共5页
Food Science
基金
广西化工过程创新技术研发平台建设项目(桂科能0992028-13)
广西自然科学基金项目(2011GXNSFC018015)
