title: Tuning the catalytic properties of lipases immobilized on divinylsulfone activated agarose by altering its nanoenvironment.
abstract: Lipase from Thermomyces lanuginosus (TLL) and lipase B from Candida antarctica (CALB) have been immobilized on divinylsulfone (DVS) activated agarose beads at pH 10 for 72 h. Then, as a reaction end point, very different nucleophiles have been used to block the support and the effect of the nature of the blocking reagent has been analyzed on the features of the immobilized preparations. The blocking has generally positive effects on enzyme stability in both thermal and organic solvent inactivations. For example, CALB improved 7.5-fold the thermal stability after blocking with imidazole. The effect on enzyme activity was more variable, strongly depending on the substrate and the experimental conditions. Referring to CALB; using p-nitrophenyl butyrate (p-NPB) and methyl phenylacetate, activity always improved by the blocking step, whatever the blocking reagent, while with methyl mandelate or ethyl hexanoate not always the blocking presented a positive effect. Other example is TLL-DVS biocatalyst blocked with Cys. This was more than 8 times more active than the non-blocked preparation and become the most active versus p-NPB at pH 7, the least active versus methyl phenylacetate at pH 5 but the third one most active at pH 9, versus methyl mandelate presented lower activity than the unblocked preparation at pH 5 and versus ethyl hexanoate was the most active at all pH values. That way, enzyme specificity could be strongly altered by this blocking step.
authors.affiliation: ICP-CSIC, Campus UAM-CSIC, Cantoblanco, 28049 Madrid, Spain; Departamento de Engenharia Química, Universidade Federal Do Ceará, Campus Do Pici, CEP 60455-760, Fortaleza, CE, Brazil.
authors.forename: Jose C S
authors.initials: JC
authors.lastname: dos Santos
authors.affiliation: ICP-CSIC, Campus UAM-CSIC, Cantoblanco, 28049 Madrid, Spain; Escuela de Química, Grupo de investigación en Bioquímica y Microbiología (GIBIM), Edificio Camilo Torres 210, Universidad Industrial de Santander, Bucaramanga, Colombia.
authors.forename: Nazzoly
authors.initials: N
authors.lastname: Rueda
authors.affiliation: Departamento de Engenharia Química, Universidade Federal Do Ceará, Campus Do Pici, CEP 60455-760, Fortaleza, CE, Brazil.
authors.forename: Luciana R B
authors.initials: LR
authors.lastname: Gonçalves
authors.affiliation: ICP-CSIC, Campus UAM-CSIC, Cantoblanco, 28049 Madrid, Spain. Electronic address: rfl@icp.csic.es.
authors.forename: Roberto
authors.initials: R
authors.lastname: Fernandez-Lafuente
mesh_terms: D001203:Ascomycota / Q000201:enzymology; D002175:Candida / Q000201:enzymology; D002384:Catalysis; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008049:Lipase / Q000378:metabolism*; D036103:Nanotechnology; D012685:Sepharose; D013379:Substrate Specificity; D013450:Sulfones
chemical_list: D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D013450:Sulfones; C009873:divinyl sulfone; D012685:Sepharose; D008049:Lipase; C431349:lipase B, Candida antarctica
keywords: Divinylsulfone support; Enzyme nano-environment; Enzyme stability; Lipase; Lipase activity; Tuning lipase properties