title: Correlation between thermostability and stability of glycosidases in ionic liquid.
abstract: The activity and stability of a β-glycosidase (Thermus thermophilus) and two α-galactosidases (Thermotoga maritima and Bacillus stearothermophilus) were studied in different hydrophilic ionic liquid (IL)/water ratios. For the ILs used, the glycosidases showed the best stability and activity in 1,3-dimethylimidazolium methyl sulfate [MMIM][MeSO(4)] and 1,2,3-trimethylimidazolium methyl sulfate [TMIM][MeSO(4)]. A close correlation was observed between the thermostability of the enzymes and their stability in IL media. At high IL concentration (80%), a time-dependent irreversible denaturing effect was observed on glycosidases while, at lower concentration (<30%), a reversible inactivation affecting mainly the k (cat) was obtained. The results demonstrate that highly thermostable glycosidases are more suitable for biocatalytic reactions in water-miscible ILs.
authors.affiliation: Biotechnologie, Biocatalyse et Biorégulation, UMR 6204 CNRS, Université de Nantes, 2, rue de la Houssinière, 44322, Nantes cedex 03, France.
authors.forename: Salim
authors.initials: S
authors.lastname: Ferdjani
authors.forename: Marina
authors.initials: M
authors.lastname: Ionita
authors.forename: Bimalendu
authors.initials: B
authors.lastname: Roy
authors.forename: Michel
authors.initials: M
authors.lastname: Dion
authors.forename: Zeineddine
authors.initials: Z
authors.lastname: Djeghaba
authors.forename: Claude
authors.initials: C
authors.lastname: Rabiller
authors.forename: Charles
authors.initials: C
authors.lastname: Tellier
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D055162:Biocatalysis; D001709:Biotechnology; D004795:Enzyme Stability; D001411:Geobacillus stearothermophilus / Q000201:enzymology / Q000235:genetics; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D057927:Hydrophobic and Hydrophilic Interactions; D007093:Imidazoles; D052578:Ionic Liquids; D007700:Kinetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013696:Temperature; D020124:Thermotoga maritima / Q000201:enzymology / Q000235:genetics; D016963:Thermus thermophilus / Q000201:enzymology / Q000235:genetics; D014867:Water; D000519:alpha-Galactosidase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: C516814:1,3-dimethylimidazolium; D001426:Bacterial Proteins; D007093:Imidazoles; D052578:Ionic Liquids; D011994:Recombinant Proteins; D014867:Water; D006026:Glycoside Hydrolases; D000519:alpha-Galactosidase