Mohamed Saleh A, Salah Hala A, Moharam Maysa E, Foda M S, Fahmy Afaf S
Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
Molecular Biology Department, National Research Centre, Dokki, Cairo, Egypt.
J Genet Eng Biotechnol. 2015 Jun;13(1):65-69. doi: 10.1016/j.jgeb.2014.12.001. Epub 2014 Dec 30.
Two inulinases (Inu2 and Inu3) were purified from NRRL 2710 by chromatography on DEAE-Sepharose and Sephacryl S-200 columns. The molecular weight of Inu2 and Inu3 were determined to be 76 and 30 kDa, respectively. Inu2 and Inu3 had the same pH optimum at 5.0, temperature optimum at 50 and 60 °C, and thermal stability up to 60 and 70 °C for 1 h, respectively. Inu2 and Inu3 had low km values (0.93 and 0.70 mM, respectively) indicating the high affinity toward inulin. Mg, Ca, Zn and EDTA did not significantly influence the enzyme activity. Ni, Cu, Fe and Co showed a partial inhibitory effect, and Hg had a strong inhibitory effect. -Chloromercuribenzoate had a partial inhibitory effect on Inu2. From these findings, inulinases can be beneficial enzymes for industrial enzymatic production of high fructose syrup.
通过在DEAE-琼脂糖和Sephacryl S-200柱上进行色谱分离，从NRRL 2710中纯化出两种菊粉酶（Inu2和Inu3）。Inu2和Inu3的分子量分别测定为76 kDa和30 kDa。Inu2和Inu3的最适pH均为5.0，最适温度分别为50和60℃，热稳定性分别高达60和70℃达1小时。Inu2和Inu3的米氏常数较低（分别为0.93和0.70 mM），表明对菊粉具有高亲和力。镁、钙、锌和乙二胺四乙酸对酶活性没有显著影响。镍、铜、铁和钴表现出部分抑制作用，汞具有强烈的抑制作用。对氯汞苯甲酸对Inu2有部分抑制作用。从这些发现来看，菊粉酶可能是工业酶法生产高果糖糖浆的有益酶。
