研究了马肝醇脱氢酶(HLADH)在含离子液体1-丁基-3-甲基咪唑氯酸盐([bmim]Cl)的反应介质中的催化特性. 以乙醇为底物时,该酶在[bmim]Cl含量≤0.15 g/ml的体系中的活力高于在不含离子液体的体系中的活力; 离子液体浓度过高(>0.15 g/ml)对酶活性有明显的抑制作用. 反应温度和pH对含离子液体的反应介质中酶活力的影响规律与不含离子液体时的规律相似. 与不含离子液体的反应介质相比, HLADH在含0.05 g/ml [bmim]Cl的体系中催化乙醇氧化的活化能下降,酶反应的Vmax 和Km均升高. 反应体系中低浓度(≤0.1 g/ml)的离子液体能提高酶的热稳定性,但高浓度(>0.1 g/ml)的离子液体可降低酶的热稳定性. 紫外二阶导数光谱显示,在含不同浓度离子液体的反应介质中酶分子构象的变化有较大的差异.
参考文献
[1] | Welton T .[J].Chemical Reviews,1999,99(08):2071. |
[2] | Zhao H;Malhotra SV .Enzymatic resolution of amino acid esters using ionic liquid N-ethyl pyridinium trifluoroacetate[J].Biotechnology Letters,2002(15):1257-1260. |
[3] | Laszlo J A;Compton D L .[J].Biotechnology and Bioengineering,2001,75(02):181. |
[4] | Lau R M;van Rantwijk F;Seddon K R;Sheldon R A .[J].Organic Letters,2000,2(26):4189. |
[5] | Kim M-J;Choi M Y;Lee J K;Ahn Y .[J].Journal of Molecular Catalysis B:Enzymatic,2003,26(3-6):115. |
[6] | Okrasa K.;Guibe-Jampel E.;Therisod M. .Ionic liquids as a new reaction medium for oxidase-peroxidase-catalyzed sulfoxidation[J].Tetrahedron, Asymmetry: The International Journal for Repid Publication on all Aspects of Asymmetry in Orgainc, Inorganic, Organometallic, Physical and Bio-Organic Chemistry,2003(17):2487-2490. |
[7] | Lou W-Y;Zong M-H;Wu H .[J].Biocatalysis and Biotransformation,2004,22(03):171. |
[8] | Eckstein M;Villela Filho M;Liese A;Kragl U.[J].Chemical Communications,2004(09):1084. |
[9] | Vallee B L;Hoch F L .[J].Proceedings of the National Academy of Sciences of the United States of America,1955,41(06):327. |
[10] | Kragl U;Kaftzik N;Schofer S H et al.[J].Chim Oggi/Chem Today,2001,19(7-8):22. |
[11] | Zhang T.;Zhou HM. .COMPARISON OF INACTIVATION AND UNFOLDING OF YEAST ALCOHOL DEHYDROGENASE DURING DENATURATION IN UREA SOLUTIONS[J].International Journal of Biological Macromolecules: Structure, Function and Interactions,1996(2):113-119. |
[12] | Ragone R;Colonna G;Balestrieri C et al.[J].Biochemistry,1984,23(08):1871. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%