title: Synthesis of carbohydrates in a continuous flow reactor by immobilized phosphatase and aldolase.
abstract: Herein, we report a new flow process with immobilized enzymes to synthesize complex chiral carbohydrate analogues from achiral inexpensive building blocks in a three-step cascade reaction. The first reactor contained immobilized acid phosphatase, which phosphorylated dihydroxyacetone to dihydroxyacetone phosphate using pyrophosphate as the phosphate donor. The second flow reactor contained fructose-1,6-diphosphate aldolase (RAMA, rabbit muscle aldolase) or rhamnulose-1-phosphate aldolase (RhuA from Thermotoga maritima) and acid phosphatase. The immobilized aldolases coupled the formed dihydroxyacetone phosphate to aldehydes, resulting in phosphorylated carbohydrates. A final reactor containing acid phosphatase that dephosphorylated the phosphorylated product yielded the final product. Different aldehydes were used to synthesize carbohydrates on a gram scale. To demonstrate the feasibility of the flow systems, we synthesized 0.6 g of the D-fagomine precursor. By using immobilized aldolase RhuA we were also able to obtain other stereoisomers of the D-fagomine precursor.
authors.affiliation: Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
authors.forename: Lara
authors.initials: L
authors.lastname: Babich
authors.forename: Aloysius F
authors.initials: AF
authors.lastname: Hartog
authors.forename: Lieke J C
authors.initials: LJ
authors.lastname: van Hemert
authors.forename: Floris P J T
authors.initials: FP
authors.lastname: Rutjes
authors.forename: Ron
authors.initials: R
authors.lastname: Wever
mesh_terms: D000135:Acid Phosphatase / Q000737:chemistry*; D000446:Aldehyde-Lyases / Q000737:chemistry*; D000447:Aldehydes / Q000737:chemistry; D002241:Carbohydrates / Q000138:chemical synthesis* / Q000737:chemistry; D004099:Dihydroxyacetone Phosphate / Q000737:chemistry; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005634:Fructose-Bisphosphate Aldolase / Q000737:chemistry*; D015394:Molecular Structure; D009943:Organophosphorus Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D002241:Carbohydrates; D004800:Enzymes, Immobilized; D009943:Organophosphorus Compounds; D004099:Dihydroxyacetone Phosphate; D000135:Acid Phosphatase; D000446:Aldehyde-Lyases; D005634:Fructose-Bisphosphate Aldolase; C022526:rhamnulose-1-phosphate adolase