title: Purification and characterization of laccase from Pycnoporus sanguineus and decolorization of an anthraquinone dye by the enzyme.
abstract: The white rot fungus Pycnoporus sanguineus produced high amount of laccase in the basal liquid medium without induction. Laccase was purified using ultrafiltration, anion-exchange chromatography, and gel filtration. The molecular weight of the purified laccase was estimated as 61.4 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme oxidized typical substrates of laccases including 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonate), 2,6-dimethoxyphenol, and syringaldazine. The optimum pH and temperature for the purified laccase were 3.0 and 65 degrees C, respectively. The enzyme was stable up to 40 degrees C, and high laccase activity was maintained at pH 2.0-5.0. Sodium azide, L-cysteine, and dithiothreitol strongly inhibited the laccase activity. The purified enzyme efficiently decolorized Remazol Brilliant Blue R in the absence of added redox mediators. The high production of P. sanguineus laccase as well as its decolorization ability demonstrated its potential applications in dye decolorization.
authors.affiliation: College of Life Sciences, Northeast Forestry University, No. 26, Hexing Road, Harbin, Heilongjiang 150040, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Lu
authors.forename: Min
authors.initials: M
authors.lastname: Zhao
authors.forename: Bei-Bei
authors.initials: BB
authors.lastname: Zhang
authors.forename: Shu-Yu
authors.initials: SY
authors.lastname: Yu
authors.forename: Xi-Jun
authors.initials: XJ
authors.lastname: Bian
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000880:Anthraquinones / Q000737:chemistry / Q000378:metabolism*; D001487:Basidiomycota / Q000201:enzymology*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004396:Coloring Agents / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005656:Fungal Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D006835:Hydrazones / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D042845:Laccase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D008970:Molecular Weight; D011748:Pyrogallol / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D013696:Temperature; D014461:Ultracentrifugation
chemical_list: D000880:Anthraquinones; D004396:Coloring Agents; D005656:Fungal Proteins; D006835:Hydrazones; D011748:Pyrogallol; C009370:syringaldazine; C010120:pyrogallol 1,3-dimethyl ether; D042845:Laccase; C024758:Remazol Brilliant Blue R