卵磷脂反胶束体系中β-1,4葡萄糖苷酶的研究  

Study of β-1,4 glucosidase in Water/PC/Heptane Butanol Reverse Micelles

作　　者：缪炜[1] 姚松年[1] 

机构地区：[1]武汉大学测试中心,武汉430072

出　　处：《物理化学学报》1999年第10期930-937,共8页Acta Physico-Chimica Sinica

摘　　要：测定了水、醋酸缓冲液和水杨苷醋酸 /醋酸钠缓冲液在水 /PC/庚烷 正丁醇反胶束体系中的饱和增溶量 ,利用UV、FT IR和NMR等技术考察了增溶到水 /PC/庚烷 正丁醇反胶束体系中的 β 1 ,4葡萄糖苷酶及水杨苷的结构变化 ,并研究了 β 1 ,4葡萄糖苷酶在水 /PC/庚烷 正丁醇反胶束中的活性 .发现了 β 1 ,4葡萄糖苷酶在水 /PC/庚烷 正丁醇反胶束中遵循米氏反应 ,最大反应速度vmax为 1 .475mg·min-1,是其在水中的 1 1 .8倍 ,米氏常数Km 为 0 .389mg·mL-1,是其在水中的 1 / 2 5 .β 1 ,4葡萄糖苷酶在水 /PC/庚烷 正丁醇反胶束中表现出的低底物浓度下的高催化速度 ,是微乳的界面发生的相互作用改变了 β 1 ,4葡萄糖苷酶的构象 ,增加了底物水杨苷的浓度 ,PC极性头部 -N+(CH3 ) 3 正离子作用水杨苷糖苷键的氧有利于糖苷键的断裂等因素造成的 .The maximum solubilization of water,acetic buffer and salicin in H 2O/PC/Heptan Butanol reverse micelles were measured.The change of structure of β 1,4 glucosidase and sali cin in this system was investigated by UV ,FT IR and NMR. The activity and kinetics of β 1,4 glucosidase in this system were also studied.The results indicated that β 1,4 glucosidase follows the Michaelis Menten kinetics in this reverse micelles,the v max is 1.475mg·min -1 ,11.8 times larger than that in aqueous,the K m is 0.389mg·mL -1 only 1/25 of that in aqueous. The reasons which cause this phenomenon are that the interaction at the interface of the reverse micelles changes the structure of β 1,4 glucosidase ,increases the concentration of salicin ,and that the -N +(CH 3) 3 in PC′polar head attacks the oxygen of the glycoside bond of salicin .

关 键 词：纤维素酶 葡萄糖苷酶 卵磷脂 反胶束 微乳液 

分 类 号：Q550.3[生物学—生物化学]