Synthesis of D-Sorbose and D-Psicose by RecombinantEscherichia coli

Abstract

In the current work, the in vitro synthetic system for rare sugars was successfully transformed into an engineered Escherichia coli with a plasmid containing both the aldolase RhaD and phosphatase YqaB. By taking advantage of the inherent biosynthetic pathways in E. coli, this approach permits the use of simple and cheap glycerol for the synthesis of DHAP in vivo. Moreover, the introduction of the phosphatase into the E. coli system allows for the removal of the phosphate group on the synthetic intermediate to yield the neutral rare sugars, which can be readily secreted to the medium without accumulation in the cell.

Recent Advances Regarding the Physiological Functions and Biosynthesis of D-Allulose

“…However, there are several routes for DHAP synthesis via enzymatic strategies. For instance, DHAP can be obtained via dihydroxyacetone (DHA), glycerol or glycerol 3-phosphate or through metabolic pathways from an inexpensive raw material, such as glucose or glycerol ( Figure 6 ; Sánchez-Moreno et al, 2004 ; Li et al, 2012 , 2015a ; Wei et al, 2015 ; Yang et al, 2015 , 2016 ). In engineered E .…”

“…In addition, D-allulose and D-sorbose have been produced in a recombinant E. coli strain overexpressing aldolase RhaD and YqaB from glycerol by fermentation. After 15 h of fermentation, the concentrations of D-sorbose (1.6 g/L) and D-allulose (1.23 g/L) were determined in the supernatant ( Li et al, 2015a ). Recently, our group constructed an efficient system for whole-cell cascade synthesis of D-sorbose and D-allulose from glycerol and D-glyceraldehyde, which yielded 15.3 g/L of D-sorbose and 6.4 g/L of D-allulose in a batch biotransformation ( Chen et al, 2020a ).…”

One-Pot Multienzyme Synthesis of Rare Ketoses from Glycerol

“…However, the carbon fragments/starting materials glycerol 3-phosphate and d- / l -glyceraldehyde ( d- / l -GA) are still either expensive and/or relatively unstable. In fact, glycerol 3-phosphate could be produced from glycerol via direct phosphorylation either by glycerol kinase with adenosine 5′-triphosphate as a cofactor or in a more economical and greener way by phytase using inexpensive pyrophosphate (PPi) as the phosphate donor . One extra benefit of using phytase is that it could also remove the phosphate group in the aldol adduct under acidic conditions (pH 4.0) to achieve phosphate recycling in the synthesis.…”

Production of d‐allulose from d‐glucose by Escherichia coli transformant cells co‐expressing d‐glucose isomerase and d‐psicose 3‐epimerase genes

“…Using a two‐step approach for the isomerisation of d ‐allulose that employed GIase from Thermus thermophilus and DPEase from Agrobacterium tumefaciens immobilised on Saccharomyces cerevisiae , a yield of 12% was achieved . For the synthesis of rare sugars, d ‐sorbose and d ‐allulose, a multi‐enzymatic system that contained both phosphatase (YqaB) and l ‐rhamnulose‐1‐phosphate aldolase (RhaD) was constructed and over‐expressed in E. coli . The biocatalytic production of d ‐allulose using the co‐expression system developed in this study yielded 42.4, 125.5 and 204.3 g L −1 of d ‐fructose and 18.2, 54.0 and 89.1 g L −1 of d ‐allulose, using initial concentrations of 100, 300 and 500 g L −1 of d ‐glucose (Fig.…”