Premium
Production of d ‐allulose from d ‐glucose by Escherichia coli transformant cells co‐expressing d ‐glucose isomerase and d ‐psicose 3‐epimerase genes
Author(s) -
Zhang Wenli,
Li Hao,
Jiang Bo,
Zhang Tao,
Mu Wanmeng
Publication year - 2017
Publication title -
journal of the science of food and agriculture
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.782
H-Index - 142
eISSN - 1097-0010
pISSN - 0022-5142
DOI - 10.1002/jsfa.8193
Subject(s) - bioconversion , fructose , monosaccharide , escherichia coli , chemistry , biochemistry , recombinant dna , glucose 6 phosphate isomerase , substrate (aquarium) , epimer , isomerase , strain (injury) , enzyme , stereochemistry , fermentation , biology , gene , ecology , anatomy
BACKGROUND d ‐Allulose is a novel and low‐calorie rare monosaccharide that is a C‐3 epimer of d ‐fructose. Because of its excellent physiological properties and commercial potential, d ‐allulose has attracted researchers' interests. Based on the Izumoring strategy, d ‐allulose is converted from d ‐fructose by d ‐psicose 3‐epimerase ( DPEase ), while d ‐fructose is converted from d ‐glucose by d ‐glucose isomerase ( GIase ). In this study, we created a cellular system capable of converting d ‐glucose to d ‐allulose in a one‐step process that co‐expressed the GIase from Acidothermus cellulolyticus and the DPEase from Dorea sp. CAG . RESULTS The co‐expression plasmid pETDuet ‐Dosp‐ DPE /Acce‐ GI was generated and transformed into Escherichia coli BL21 ( DE3 ) cells. The recombinant co‐expression cells exhibited maximum catalytic activity at pH 6.5 and 75 °C. These cells were thermostable at less than 60 °C. The addition of Co 2+ significantly increased the catalytic activity by 10.8‐fold. When the reaction equilibrium was reached, the ratio of d ‐glucose, d ‐fructose and d ‐allulose was approximately 6.5:7:3, respectively. CONCLUSION A recombinant co‐expression strain that catalysed the bioconversion of d ‐allulose from d ‐glucose in a one‐step process was created and characterised. When adding 500 g L −1 d ‐glucose as a substrate, 204.3 g L −1 d ‐fructose and 89.1 g L −1 d ‐allulose were produced. © 2016 Society of Chemical Industry