title: Enhanced functionality and stabilization of a cold active laccase using nanotechnology based activation-immobilization.
abstract: A simple nanotechnology based immobilization technique for imparting psychrostability and enhanced activity to a psychrophilic laccase has been described here. Laccase from a psychrophile was supplemented with Copper oxide nanoparticles (NP) corresponding to copper (NP-laccase), the cationic activator of this enzyme and entrapped in single walled nanotube (SWNT). The activity and stability of laccase was enhanced both at temperatures as low as 4°C and as high as 80°C in presence of NP and SWNT. The enzyme could be released and re-trapped (in SWNT) multiple times while retaining significant activity. Laccase, immobilized in SWNT, retained its activity after repeated freezing and thawing. This unique capability of SWNT to activate and stabilize cold active enzymes at temperatures much lower or higher than their optimal range may be utilized for processes that require bio-conversion at low temperatures while allowing for shifts to higher temperature if so required.
authors.affiliation: Department of Biochemistry, University of Calcutta, West Bengal, India.
authors.forename: Arka
authors.initials: A
authors.lastname: Mukhopadhyay
authors.affiliation: Department of Biochemistry, University of Calcutta, West Bengal, India.
authors.forename: Anjan Kr
authors.initials: AK
authors.lastname: Dasgupta
authors.affiliation: Department of Biochemistry, University of Calcutta, West Bengal, India. Electronic address: kcbioc@gmail.com.
authors.forename: Krishanu
authors.initials: K
authors.lastname: Chakrabarti
mesh_terms: D003080:Cold Temperature; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005615:Freezing; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D042845:Laccase / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D053758:Nanoparticles; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry; D017433:Protein Structure, Secondary; D016958:Pseudomonas putida / Q000201:enzymology; D059027:Recycling; D013997:Time Factors
chemical_list: D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D042845:Laccase
keywords: Enzyme stability; Immobilisation; Kinetics determinants; Reusability; Single wall carbon nanotubes