title: Enhancing the thermal stability of lipases through mutagenesis and immobilization on zeolites.
abstract: The hydrolysis reaction of p-nitrophenyl butyrate catalyzed by lipases was followed with in situ UV/vis diode array spectrophotometry. Five enzymes - Candida antarctica lipase B and Fusarium solani pisi cutinase wild-type and three single-mutation variants - were tested as catalysts in homogeneous conditions and immobilized on zeolite NaY, on a polyacrylate support and as cross-linked aggregates. Using deconvolution techniques and kinetic modeling, the thermal stability of the different biocatalysts was compared in operational conditions and the results were supported by steady-state enzyme fluorescence measurements. We concluded that both the mutagenesis and the immobilization on zeolite NaY had a positive effect on the thermal stability of F. solani pisi cutinase.
authors.affiliation: IBB-Institute for Biotechnology and Bioengineering, Centre for Biological and Chemical Engineering, Instituto Superior Técnico, Lisbon, Portugal. luis.costa@ist.utl.pt
authors.forename: L
authors.initials: L
authors.lastname: Costa
authors.forename: V
authors.initials: V
authors.lastname: Brissos
authors.forename: F
authors.initials: F
authors.lastname: Lemos
authors.forename: F Ramôa
authors.initials: FR
authors.lastname: Ribeiro
authors.forename: J M S
authors.initials: JM
authors.lastname: Cabral
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D002175:Candida / Q000201:enzymology; D002384:Catalysis; D005656:Fungal Proteins; D005670:Fusarium / Q000378:metabolism; D006868:Hydrolysis; D007700:Kinetics; D008049:Lipase / Q000032:analysis* / Q000737:chemistry; D015233:Models, Statistical; D016296:Mutagenesis; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013696:Temperature; D013997:Time Factors; D017641:Zeolites / Q000378:metabolism*
chemical_list: D000180:Acrylic Resins; D005656:Fungal Proteins; D017641:Zeolites; C006903:carbopol 940; D008049:Lipase; C431349:lipase B, Candida antarctica