title: 1,4-Anhydrogalactopyranose is not an intermediate of the mutase catalyzed UDP-galactopyranose/furanose interconversion.
abstract: UDP-galactopyranose mutase (UGM) catalyzes the isomerization of UDP-galactopyranose (UDP-Galp) into UDP-galactofuranose (UDP-Galf), an essential step of the mycobacterial cell wall biosynthesis. The first mechanistic assumption proposed in the literature was the involvement of 1,4-anhydrogalactose 1 as intermediate of this ring contraction. To confirm or rule out this hypothesis, we synthesized 1 and engaged it in reactions with UGM. The expected formations of UDP-Galf and UDP-Galp were never observed, thus showing that 1 is not, in fact, a low energy intermediate of this enzymatic contraction.
authors.affiliation: Ecole Normale Supérieure, Département de Chimie, Institut de Chimie Moléculaire (FR 2769), UMR 8642: CNRS-ENS-UPMC Paris 6, 24 rue Lhomond, 75231 Paris Cedex 05, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Caravano
authors.forename: Pierre
authors.initials: P
authors.lastname: Sinaÿ
authors.forename: Stéphane P
authors.initials: SP
authors.lastname: Vincent
mesh_terms: D002384:Catalysis; D004338:Drug Combinations; D005690:Galactose / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D019751:Intramolecular Transferases / Q000378:metabolism*; D015394:Molecular Structure; D009821:Oils; D010636:Phenols; D013696:Temperature; D014530:Uridine Diphosphate / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: C508851:1,4-anhydrogalactopyranose; D004338:Drug Combinations; D009821:Oils; C027222:P & S Liquid; D010636:Phenols; C104136:uridine diphosphate galactofuranose; D014530:Uridine Diphosphate; D019751:Intramolecular Transferases; C098051:UDP-galactopyranose mutase; D005690:Galactose