title: Purification and characterization of an extracellular laccase from the anthracene-degrading fungus Fusarium solani MAS2.
abstract: An extracellular laccase was purified from the culture medium of the non-white rot, anthracene-degrading fungal strain Fusarium solani MAS2. Both native PAGE and SDS-PAGE revealed one single band corresponding to a molecular weight of about 72 kDa. Treatment with endoglycosidase H reduced the molecular weight by 12%. The purified laccase maintained stable at pH 3-11 and up to 50 degrees C. The highest activity was detected at pH 3.0 and at 70 degrees C. The enzyme retained 46.2-97.2% of it activity in the presence of 20mM Pb(2+), Ni(2+), Cr(3+), and its activity was enhanced in the presence of 20mM Hg(2+). The laccase retained more than 50% of its activity in the presence of 5% acetone, acetonitrile, dimethyl sulphoxide (DMSO), ethanol and methanol. The kinetic constants (K(m) and k(cat)) showed that 2,6-dimethoxyphenol (DMOP) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) diammonium salt (ABTS) were the more effective substrates rather than catechol and guaiacol. The novel properties of this laccase suggest its potential for biotechnological and environmental applications.
authors: Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, PR China. oxwyr@tom.com
authors: Yi-Rui
authors: YR
authors: Wu
authors: Zhu-Hua
authors: ZH
authors: Luo
authors: R
authors: R
authors: Kwok-Kei Chow
authors: L L P
authors: LL
authors: Vrijmoed
mesh_terms: D000873:Anthracenes / Q000378:metabolism*; D001673:Biodegradation, Environmental / Q000187:drug effects; D004591:Electrophoresis, Polyacrylamide Gel; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004795:Enzyme Stability / Q000187:drug effects; D005110:Extracellular Space / Q000187:drug effects / Q000201:enzymology*; D005670:Fusarium / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D007477:Ions; D007700:Kinetics; D042845:Laccase / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism*; D019216:Metals, Heavy / Q000494:pharmacology; D009930:Organic Chemicals / Q000494:pharmacology; D010084:Oxidation-Reduction / Q000187:drug effects; D010636:Phenols / Q000494:pharmacology; D012997:Solvents / Q000494:pharmacology; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism; D013696:Temperature
chemical_list: D000873:Anthracenes; D004791:Enzyme Inhibitors; D007477:Ions; D019216:Metals, Heavy; D009930:Organic Chemicals; D010636:Phenols; D012997:Solvents; D042845:Laccase; C034020:anthracene