title: Enzymatic production of three 6-deoxy-aldohexoses from L-rhamnose.
abstract: 6-Deoxy-L-glucose, 6-deoxy-L-altrose, and 6-deoxy-L-allose were produced from L-rhamnose with an immobilized enzyme that was partially purified (IE) and an immobilized Escherichia coli recombinant treated with toluene (TT). 6-Deoxy-L-psicose was produced from L-rhamnose by a combination of L-rhamnose isomerase (TT-PsLRhI) and D-tagatose 3-epimerase (TT-PcDTE). The purified 6-deoxy-L-psicose was isomerized to 6-deoxy-L-altrose and 6-deoxy-L-allose with L-arabinose isomerase (TT-EaLAI) and L-ribose isomerase (TT-AcLRI), respectively, and then was epimerized to L-rhamnulose with immobilized D-tagatose 3-epimerase (IE-PcDTE). Following purification, L-rhamnulose was converted to 6-deoxy-L-glucose with D-arabinose isomerase (TT-BpDAI). The equilibrium ratios of 6-deoxy-L-psicose:6-deoxy-L-altrose, 6-deoxy-L-psicose:6-deoxy-L-allose, and L-rhamnulose:6-deoxy-L-glucose were 60:40, 40:60, and 27:73, respectively. The production yields of 6-deoxy-L-glucose, 6-deoxy-L-altrose, and 6-deoxy-L-allose from L-rhamnose were 5.4, 14.6, and 25.1%, respectively. These results indicate that the aldose isomerases used in this study acted on 6-deoxy aldohexoses.
authors.affiliation: a Rare Sugar Research Center, Kagawa University , Miki , Japan.
authors.forename: Sirinan
authors.initials: S
authors.lastname: Shompoosang
authors.forename: Akihide
authors.initials: A
authors.lastname: Yoshihara
authors.forename: Keiko
authors.initials: K
authors.lastname: Uechi
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Asada
authors.forename: Kenji
authors.initials: K
authors.lastname: Morimoto
mesh_terms: D001419:Bacteria / Q000201:enzymology; D003837:Deoxy Sugars / Q000378:metabolism*; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D006601:Hexoses / Q000378:metabolism*; D019746:Intramolecular Oxidoreductases / Q000737:chemistry / Q000378:metabolism*; D012210:Rhamnose / Q000378:metabolism*
chemical_list: D003837:Deoxy Sugars; D004800:Enzymes, Immobilized; D006601:Hexoses; C053979:6-deoxyaltrose; D019746:Intramolecular Oxidoreductases; D012210:Rhamnose
keywords: 6-deoxy-l-allose; 6-deoxy-l-altrose; 6-deoxy-l-glucose; aldose isomerase reactivity; d-tagatose 3-epimerase reactivity