title: Araf51 with improved transglycosylation activities: one engineered biocatalyst for one specific acceptor.
abstract: A random mutagenesis of the arabinofuranosyl hydrolase Araf51 has been run in order to have access to efficient biocatalysts for the synthesis of alkyl arabinofuranosides. The mutants were selected on their ability to catalyze the transglycosylation reaction of p-nitrophenyl α-L-arabinofuranoside (pNP-Araf) used as a donor and various aliphatic alcohols as acceptors. This screening strategy underlined 5 interesting clones, each one corresponding to one acceptor. They appeared to be much more efficient in the transglycosylation reaction compared to the wild type enzyme whereas no self-condensation or hydrolysis products could be detected. Moreover, the high specificity of the mutants toward the alcohols for which they have been selected validates the screening process. Sequence analysis of the mutated enzymes revealed that, despite their location far from the active site, the mutations affect significantly the kinetics properties as well as the substrate affinity of these mutants toward the alcohol acceptors in the transglycosylation reaction.
authors.affiliation: Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France; Université européenne de Bretagne, France.
authors.forename: Alizé
authors.initials: A
authors.lastname: Pennec
authors.affiliation: Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France; Université européenne de Bretagne, France.
authors.forename: Richard
authors.initials: R
authors.lastname: Daniellou
authors.affiliation: Université européenne de Bretagne, France; INSERM UMR 991, Hôpital Pontchaillou, 35033 Rennes Cedex, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Loyer
authors.affiliation: Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France; Université européenne de Bretagne, France. Electronic address: caroline.nugier@ensc-rennes.fr.
authors.forename: Caroline
authors.initials: C
authors.lastname: Nugier-Chauvin
authors.affiliation: Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France; Université européenne de Bretagne, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Ferrières
mesh_terms: D001089:Arabinose / Q000031:analogs & derivatives* / Q000378:metabolism; D055162:Biocatalysis; D048013:Acetivibrio thermocellus / Q000201:enzymology; D006026:Glycoside Hydrolases / Q000235:genetics* / Q000378:metabolism*; D006031:Glycosylation; D007700:Kinetics; D016296:Mutagenesis; D013379:Substrate Specificity
chemical_list: C431714:arabinofuranose; D001089:Arabinose; D006026:Glycoside Hydrolases
keywords: Furanosidase; Furanosides; Random mutagenesis; Transglycosylation