Zhang W, Li H, Jiang B, Zhang T, Mu W. Production of d-allulose from d-glucose by Escherichia coli transformant cells co-expressing d-glucose isomerase and d-psicose 3-epimerase genes.
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2017;
97:3420-3426. [PMID:
28009059 DOI:
10.1002/jsfa.8193]
[Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 12/18/2016] [Accepted: 12/19/2016] [Indexed: 06/06/2023]
Abstract
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 Co2+ 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.
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