title: Enzymatic redox cofactor regeneration in organic media: functionalization and application of glycerol dehydrogenase and soluble transhydrogenase in reverse micelles.
abstract: An enzymatic system for the regeneration of redox cofactors NADH and NADPH was investigated in nanostructural reverse micelles using bacterial glycerol dehydrogenase (GLD) and soluble transhydrogenase (STH). Catalytic conversion of NAD+ to NADH was realized in the sodium dioctylsulfosuccinate (AOT)/isooctane reverse micellar system harboring GLD and a sacrificial substrate, glycerol. The initial rate of NADH regeneration was enhanced by exogenous addition of ammonium sulfate into the reverse micelles, suggesting that NH4+ acts as a monovalent cationic activator. STH was successfully entrapped in the AOT/isooctane reverse micelles as well as GLD and was revealed to be capable of catalyzing the stoichiometric hydrogen transfer reaction between NADP+ and NADPH in reverse micelles. These results indicate that GLD and STH have potential for use in redox cofactor recycling in reverse micelles, which allows the use of catalytic quantities of NAD(P)H in organic media.
authors.affiliation: Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, 4-1-8, Honmachi, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Ichinose
authors.forename: Noriho
authors.initials: N
authors.lastname: Kamiya
authors.forename: Masahiro
authors.initials: M
authors.lastname: Goto
mesh_terms: D001671:Biochemistry / Q000379:methods*; D003067:Coenzymes / Q000737:chemistry* / Q000378:metabolism; D004143:Dioctyl Sulfosuccinic Acid / Q000737:chemistry; D008823:Micelles; D009243:NAD / Q000737:chemistry / Q000378:metabolism; D009249:NADP / Q000737:chemistry / Q000378:metabolism; D009250:NADP Transhydrogenases / Q000737:chemistry* / Q000378:metabolism; D009795:Octanes / Q000737:chemistry; D009930:Organic Chemicals; D010084:Oxidation-Reduction; D012995:Solubility; D013401:Sugar Alcohol Dehydrogenases / Q000737:chemistry* / Q000378:metabolism
chemical_list: D003067:Coenzymes; D008823:Micelles; D009795:Octanes; D009930:Organic Chemicals; D009243:NAD; D004143:Dioctyl Sulfosuccinic Acid; D009249:NADP; D013401:Sugar Alcohol Dehydrogenases; C020672:glycerol dehydrogenase; D009250:NADP Transhydrogenases; C045798:2,2,4-trimethylpentane