Enhancing the thermal stability of lipases through mutagenesis and immobilization on zeolites.
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.
Costa
L
L
IBB-Institute for Biotechnology and Bioengineering, Centre for Biological and Chemical Engineering, Instituto Superior Técnico, Lisbon, Portugal. luis.costa@ist.utl.pt
Brissos
V
V
Lemos
F
F
Ribeiro
F Ramôa
FR
Cabral
J M S
JM
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*
D000180:Acrylic Resins; D005656:Fungal Proteins; D017641:Zeolites; C006903:carbopol 940; D008049:Lipase; C431349:lipase B, Candida antarctica