A four-step enzymatic cascade for the one-pot synthesis of non-natural carbohydrates from glycerol.
A total of four enzymatic steps were combined, in a one-pot reaction, to synthesize carbohydrates starting from glycerol. First, phosphorylation of glycerol by reaction with pyrophosphate in the presence of phytase at pH 4.0 in 95% glycerol afforded racemic glycerol-3-phosphate in 100% yield. The L-enantiomer of the latter underwent selective aerobic oxidation to dihydroxyacetone phosphate (DHAP) at pH 7.5 in the presence of glycerolphosphate oxidase (GPO) and catalase. Subsequently, fructose-1,6-bisphosphate aldolase catalyzed the aldol reaction of DHAP with butanal. Finally, dephosphorylation of the aldol adduct was mediated by phytase at pH 4 affording 5-deoxy-5-ethyl-D-xylulose in 57% yield from L-glycerol-3-phosphate. The phytase on/off-switch by pH was the key to controlling phosphorylation and dephosphorylation.
Schoevaart
R
R
Laboratory of Organic Chemistry and Catalysis, Delft University of Technology, Julianalaan 136, 2628 BL Delft, The Netherlands.
van Rantwijk
F
F
Sheldon
R A
RA
D002241:Carbohydrates / Q000138:chemical synthesis*; D002384:Catalysis; D011756:Diphosphates / Q000737:chemistry; D004798:Enzymes; D005990:Glycerol / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D010084:Oxidation-Reduction; D010766:Phosphorylation; D013056:Spectrophotometry, Ultraviolet
D002241:Carbohydrates; D011756:Diphosphates; D004798:Enzymes; D005990:Glycerol