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6?磷酸?β?葡萄糖苷酶( EC 3.2.1.86)催化6?磷酸-葡萄糖苷类化合物(如6?磷酸-纤维二糖、6?磷酸-纤维素寡糖)产生6?磷酸-葡萄糖而使纤维素完全分解,在微生物碳源利用过程中起重要作用。腾冲嗜热厌氧杆菌是一株嗜热厌氧微生物,提供了丰富的热稳定性蛋白基因资源。从该菌株中克隆编码6?磷酸?β?葡萄糖苷酶的基因TtebglB,并在E.coli BL21(DE3)进行了异源表达。结果表明,TteBglB催化反应的最适pH为6.0、最适温度为70℃,在pH 4~10或70℃时有着良好的稳定性;同时证实,TteBglB属于糖基水解酶家族1( GH1)成员,可不依赖Mn2+、Ni2+、Co2+或Fe2+等二价金属离子而发挥催化作用。以pNPβG6P为底物时,催化反应的Km为0.054 mmol/L,Kcat为81.47/min,Vmax为0.003992 mmol/min,酶比活为18.093 U/mg。“,”6?phosphate?β?glucosidase (EC 3.2.1.86), an enzyme catalyzes 6?phosphate?glucoside compounds (such as 6?phosphate?cellobiose, 6?phosphate?cellulose oligosaccharides ) to produce 6?phosphate?glucose, plays an important role in carbon utilization for microbes. Thermoanaerobacter tengcongensis MB4, a strain of thermophilic anaerobic microorganism, is an excellent resource for thermo?stable protein. In this study, gene TtebglB was isolated from this strain and then heterologously expressed in E. coli BL21 ( DE3 ) . The optimum pH and temperature of TteBglB were pH 6.0 and 70℃, respectively, and the enzyme kept stable at a pH 4~10 at 70℃. Additionally, it was also confirmed that TteBglB belonged to glycosyl hydrolase family 1 ( GH1) and could act without Mn2+, Ni2+, Co2+, Fe2+ and other divalent metal ions. Using pNPβG6P as substrate, the values of Km , Kcat , and Vmax for this enzyme was 0.054 mmol/L, 81.47/min and 0.003 992 mmol/min, respectively, and specific activity of the enzyme reached to 18?093 U/mg.