Enzymatic characterization of a thermostable phosphatase from Thermomicrobium roseum and its application for biosynthesis of fructose from maltodextrin.

Enzymatic characterization of a thermostable phosphatase from Thermomicrobium roseum and its application for biosynthesis of fructose from maltodextrin. Appl Microbiol Biotechnol. 2019 Jun 06;: Authors: Meng D, Liang A, Wei X, You C Abstract Phosphatases, which catalyze the dephosphorylation of compounds containing phosphate groups, are important members of the haloacid dehalogenase (HAD)-like superfamily. Herein, a thermostable phosphatase encoded by an open reading frame of Trd_1070 from Thermomicrobium roseum was enzymologically characterized. This phosphatase showed promiscuous activity against more than ten sugar phosphates, with high specific activity toward ribose 5-phosphate, followed by ribulose 5-phosphate and fructose 6-phosphate. The half-life of Trd_1070 at 70 °C and pH 7.0 was about 14.2 h. Given that the catalytic efficiency of Trd_1070 on fructose 6-phosphate was 49-fold higher than that on glucose 6-phosphate, an in vitro synthetic biosystem containing alpha-glucan phosphorylase, phosphoglucomutase, phosphoglucose isomerase, and Trd_1070 was constructed for the production of fructose from maltodextrin by whole-cell catalysis, resulting in 21.6 g/L fructose with a ratio of fructose to glucose of approximately 2:1 from 50 g/L maltodextrin. This in vitro biosystem provides an alternative method to produce fructose with higher fructose content compared with the traditional production method using glucose isomerization. ...
Source: Applied Microbiology and Biotechnology - Category: Microbiology Authors: Tags: Appl Microbiol Biotechnol Source Type: research