title: Evaluating Ketoreductase Exchanges as a Means of Rationally Altering Polyketide Stereochemistry.
abstract: Modular polyketide synthases (PKSs) are multidomain multienzymes responsible for the biosynthesis in bacteria of a wide range of polyketide secondary metabolites of clinical value. The stereochemistry of these molecules is an attractive target for genetic engineering in attempts to produce analogues exhibiting novel therapeutic properties. The exchange of ketoreductase (KR) domains in model PKSs has been shown in several cases to predictably alter the configuration of the β-hydroxy functionalities but not of the α-methyl groups. By systematic screening of a broad panel of KR domains, we have identified two donor KRs that afford modification of α-methyl group stereochemistry. To the best of our knowledge, this provides the first direct in vivo evidence of KR-catalyzed epimerization. However, none of the introduced KRs afforded simultaneous alteration of methyl and hydroxy configurations in high yield. Therefore, swapping of whole modules might be necessary to achieve such changes in stereochemistry.
authors: UMR 7365, Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA), CNRS-Université de Lorraine, Biopôle de l'Université de Lorraine, Campus biologie-santé, 9 Avenue de la Forêt de Haye, CS 50184, 54505 Vandœuvre-lès-Nancy Cedex (France).
authors: Thibault
authors: T
authors: Annaval
authors: Laboratoire d'Ingénierie des Biomolécules, Ecole Nationale Supérieure d'Agronomie et des Industries Alimentaires (ENSAIA), Université de Lorraine, 2, Avenue de la Fôret de Haye, B. P. 172, 54518 Vandœuvre-lès-Nancy Cedex (France).
authors: Cédric
authors: C
authors: Paris
authors: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA (UK).
authors: Peter F
authors: PF
authors: Leadlay
authors: UMR 7365, Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA), CNRS-Université de Lorraine, Biopôle de l'Université de Lorraine, Campus biologie-santé, 9 Avenue de la Forêt de Haye, CS 50184, 54505 Vandœuvre-lès-Nancy Cedex (France). christophe.jacob@univ-lorraine.fr.
authors: Christophe
authors: C
authors: Jacob
authors: UMR 7365, Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA), CNRS-Université de Lorraine, Biopôle de l'Université de Lorraine, Campus biologie-santé, 9 Avenue de la Forêt de Haye, CS 50184, 54505 Vandœuvre-lès-Nancy Cedex (France). kira.weissman@univ-lorraine.fr.
authors: Kira J
authors: KJ
authors: Weissman
mesh_terms: D000429:Alcohol Oxidoreductases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D048630:Polyketide Synthases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D061065:Polyketides / Q000737:chemistry / Q000378:metabolism*; D015202:Protein Engineering; D017434:Protein Structure, Tertiary; D013237:Stereoisomerism; D013302:Streptomyces / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D061065:Polyketides; D048630:Polyketide Synthases; D000429:Alcohol Oxidoreductases; C087192:polyketide synthase ketoreductase
keywords: biosynthesis; genetic engineering; ketoreductases; polyketides; stereocontrol