检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:周闯[1] 田桂玲[1] 沈鸿雁[1] 叶蕴华[1]
机构地区:[1]北京大学
出 处:《化学学报》2001年第10期1707-1711,共5页Acta Chimica Sinica
基 金:国家自然科学基金
摘 要:必需水的存在是酶在有机溶剂中保持活性的关键.本文研究了自由水初始水含量对有机溶剂中α-胰凝乳蛋白酶(α-chymotrvpsin)和嗜热杆菌蛋白酶粗品(thermoase)催化合成寡肽的影响.用无机盐水合物Na2SO4@10H2O和Na2CO3@10H2O代替自由水重复了上述反应.实验表明,足量的无机盐水合物能在有机溶剂中可逆地失去自身所带的结晶水,因而能代替自由水来提供酶所需的'必需水',并有效地控制有机溶剂中酶促反应体系的水活度(aw)值。Essential water is very important for the enzyme to keep its bioactivity in organic solvents. The effect of free water content on the synthesis of Z - Tyr - Gly - Gly - OEt and Z - Tyr - Gly - NHNHPh by alpha -chymotrypsin and Boc - Phe - Ala - NHNHPh by thermoase in various organic solvents, including dichloromethane, cyclohexane, ethyl acetate and toluene, was investigated. By replacing free water with salt hydrates such as Na2SO4 . 10H(2)O or Na2CO3 . 10H(2)O, the effect of salt hydrates on the above reaction systems was also discussed. The results indicated that essential water can be supplied by salt hydrates, and water activity (a(w)) of the synthetic reaction system can also be fixed by salt hydrates, both favoring the formation of peptide bonds.
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.28