生物技术通报2024，Vol.40Issue(7)：299-306,8.DOI:10.13560/j.cnki.biotech.bull.1985.2024-0095
糖磷酸酶的挖掘及其酶学性质研究
Identification and Enzymatic Characterization of a Sugar Phosphatase
摘要
Abstract
[Objective]High value-added monosaccharides can be synthesized through multi-enzyme cascade reactions using starch or dextrin as substrates.In the reaction systems,sugar phosphatase catalyzes the irreversible dephosphorylation reaction of the phosphorylated sugar intermediates to generate the corresponding sugars.This work is aimed to mine the new sugar phosphatase and to characterize this enzyme.[Method]In this study,a gene with unknown function,named as TsPase derived from the thermophilic bacterium Thermoproteus sp.CIS_19,was obtained from gene mining and screening.TsPase was found to have sugar phosphatase activity after its heterologous soluble expression with Escherichia coli BL21(DE3),purification and enzymatic characterization.[Result]TsPase has a Tm value of(80.3±1.3)℃,while the optimal reaction temperature of 70℃and pH of 4.Our study indicated that metal ion Mg2+has a strong promoting effect on TsPase.With the substrate tagatose 6 phosphate kinetic constant Km is(2.40±0.98)mmol/L,and the catalytic constant kcat is(102.50±8.60)min-1.TsPase was integrated into an in vitro synthetic enzymatic biosystem for the one-pot production of D-tagatose from maltodextrin.The production of D-tagatose in the reaction equilibrium system was(4.26±0.03)g/L and the conversion rate reach 42.6%±0.3%.[Conclusion]Overall,TsPase possesses fine thermal stability and activity,as well as high conversation rate in vitro synthetic enzymatic biosystem.These characteristics make it great value in future theoretical research and industrial production.关键词
糖磷酸酶/酶学特性/热稳定性/基因挖掘Key words
sugar phosphatase/enzymatic characterization/thermal stability/gene mining引用本文复制引用
乔烨,张楠,杨建花,张翠英,朱蕾蕾..糖磷酸酶的挖掘及其酶学性质研究[J].生物技术通报,2024,40(7):299-306,8.基金项目
国家重点研发计划(2023YFA0914000) （2023YFA0914000）
