title: Production of (R)-Ethyl-4-Chloro-3-Hydroxybutanoate Using Saccharomyces cerevisiae YOL151W Reductase Immobilized onto Magnetic Microparticles.
abstract: For the synthesis of various pharmaceuticals, chiral alcohols are useful intermediates. Among them, (R)-ethyl-4-chloro-3-hydroxybutanoate ((R)-ECHB) is an important building block for the synthesis of L-carnitine. (R)-ECHB is produced from ethyl-4-chloro-3-oxobutanoate (ECOB) by a reductase-mediated, enantioselective reduction reaction. The Saccharomyces cerevisiae YOL151W reductase that is expressed in Escherichia coli cells exhibited an enantioselective reduction reaction toward ECOB. By virtue of the C-terminal His-tag, the YOL151W reductase was purified from the cell-free extract using Ni(2+)-NTA column chromatography and immobilized onto Ni(2+)-magnetic microparticles. The physical properties of the immobilized reductase (Imm-Red) were measured using electron microscopy, a magnetic property measurement system, and a zeta potential system; the average size of the particles was approximately 1 μm and the saturated magnetic value was 31.76 emu/g. A neodymium magnet was used to recover the immobilized enzyme within 2 min. The Imm-Red showed an optimum temperature at 45°C and an optimum pH at 6.0. In addition, Bacillus megaterium glucose dehydrogenase (GDH) was produced in the E. coli cells and was used in the coupling reaction to regenerate the NADPH cofactor. The reduction/oxidation coupling reaction composed of the Imm-Red and GDH converted 20 mM ECOB exclusively into (R)- ECHB with an e.e.p value of 98%.
authors.affiliation: Department of Biotechnology, The Catholic University of Korea, Bucheon 420-743, Republic of Korea.
authors.forename: Jin Woo
authors.initials: JW
authors.lastname: Choo
authors.affiliation: Department of Biotechnology, The Catholic University of Korea, Bucheon 420-743, Republic of Korea.
authors.forename: Hyung Kwoun
authors.initials: HK
authors.lastname: Kim
mesh_terms: D001410:Bacillus megaterium / Q000201:enzymology / Q000235:genetics; D002087:Butyrates / Q000378:metabolism*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D042843:Glucose 1-Dehydrogenase / Q000235:genetics / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D060328:Magnetic Phenomena; D008854:Microscopy, Electron; D009249:NADP / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D013696:Temperature
chemical_list: D002087:Butyrates; D004800:Enzymes, Immobilized; D029701:Saccharomyces cerevisiae Proteins; C121244:ethyl 4-chloro-3-hydroxybutanoate; D009249:NADP; D010088:Oxidoreductases; C432953:GRE2 protein, S cerevisiae; D042843:Glucose 1-Dehydrogenase
keywords: Reductase; chiral intermediate; coupling reaction; immobilized enzyme; magnetic particle