title: Biocatalytic racemization of sec-alcohols and alpha-hydroxyketones using lyophilized microbial cells.
abstract: Biocatalytic racemization of aliphatic and aryl-aliphatic sec-alcohols and alpha-hydroxyketones (acyloins) was accomplished using whole resting cells of bacteria, fungi, and one yeast. The mild (physiological) reaction conditions ensured the suppression of undesired side reactions, such as elimination or condensation. Cofactor and inhibitor studies suggest that the racemization proceeds through an equilibrium-controlled enzymatic oxidation-reduction sequence via the corresponding ketones or alpha-diketones, respectively, which were detected in various amounts. Ketone formation could be completely suppressed by exclusion of molecular oxygen. Figure Biocatalytic racemization whole microbial cells.
authors.affiliation: Department of Chemistry, Organic and Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria.
authors.forename: Bettina M
authors.initials: BM
authors.lastname: Nestl
authors.forename: Constance V
authors.initials: CV
authors.lastname: Voss
authors.forename: Anne
authors.initials: A
authors.lastname: Bodlenner
authors.forename: Ursula
authors.initials: U
authors.lastname: Ellmer-Schaumberger
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kroutil
authors.forename: Kurt
authors.initials: K
authors.lastname: Faber
mesh_terms: D000438:Alcohols / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D001419:Bacteria / Q000254:growth & development / Q000378:metabolism; D001709:Biotechnology / Q000379:methods*; D002384:Catalysis; D005233:Fatty Alcohols / Q000737:chemistry / Q000378:metabolism*; D005612:Freeze Drying; D005658:Fungi / Q000254:growth & development / Q000378:metabolism; D006801:Humans; D007659:Ketones / Q000737:chemistry / Q000378:metabolism; D010084:Oxidation-Reduction; D013237:Stereoisomerism; D015003:Yeasts / Q000254:growth & development / Q000378:metabolism
chemical_list: D000438:Alcohols; D005233:Fatty Alcohols; D007659:Ketones; C011159:acyloin