title: Thermostability, pH stability and dye degrading activity of a bacterial laccase are enhanced in the presence of Cu2O nanoparticles.
abstract: The present study relates to a nanotechnology enabled method in which purified laccase from Escherichia coli AKL2 was supplemented with 100 μM copper oxide nanoparticles (Cu(2)O) (NP-laccase). The activity, half life and stability of NP-laccase were enhanced by 4, 42 and 36-fold respectively at high temperature (80 °C) and also over a wide range of pH (4-12) than laccase (in the presence of 0.18 mM CuSO(4)). Thermodynamic analysis of the nanoparticle-induced enzyme stability revealed an enhanced entropy-enthalpy compensation at 80 °C, which reflected the maintenance of its native structure. This was further supported by CD studies. The enhanced activity and thermostability of NP-laccase can be utilized for efficient decolorisation of dyes (both phenolic and azo).
authors.affiliation: Department of Biochemistry, University College of Science, Calcutta University, 35 Ballygunge Circular Road, West Bengal, Kolkata 700 019, India.
authors.forename: Arka
authors.initials: A
authors.lastname: Mukhopadhyay
authors.forename: Anjan Kumar
authors.initials: AK
authors.lastname: Dasgupta
authors.forename: Krishanu
authors.initials: K
authors.lastname: Chakrabarti
mesh_terms: D042081:Azospirillum lipoferum / Q000201:enzymology* / Q000235:genetics; D001483:Base Sequence; D002942:Circular Dichroism; D004396:Coloring Agents / Q000378:metabolism*; D003300:Copper / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D042845:Laccase / Q000378:metabolism*; D053768:Metal Nanoparticles; D008969:Molecular Sequence Data; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D021521:Ribotyping; D017422:Sequence Analysis, DNA; D013696:Temperature; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
chemical_list: D004396:Coloring Agents; D012336:RNA, Ribosomal, 16S; D014874:Water Pollutants, Chemical; D003300:Copper; D042845:Laccase; C000520:cuprous oxide