title: Purification of a laccase from fruiting bodies of the mushroom Pleurotus eryngii.
abstract: A purification scheme involving ion exchange chromatography on diethylaminoethyl (DEAE) cellulose, carboxymethyl (CM) cellulose, and Q-Sepharose, followed by fast protein liquid chromatography-gel filtration on Superdex 75, was utilized to isolate a laccase from the fruiting bodies of the mushroom Pleurotus eryngii. The laccase was adsorbed on DEAE-cellulose and Q-Sepharose and unadsorbed on CM-cellulose. The molecular mass of the laccase in sodium dodecyl sulfate-polyacrylamide gel electrophoresis was 34 kDa. The laccase activity was maximal at 70 degrees C and remained high at 80 degrees C. High activity of the laccase was maintained at ph 3 to 5. The activity underwent an abrupt decline at pH 6 and 7 and was indiscernible at ph 8 and 9. The laccase exhibited an inhibitory activity toward HIV-1 reverse transcriptase with an IC50 of 2.2 microM. Its N-terminal sequence was dissimilar to those of laccase isoenzymes previously isolated from cultured mycelia of the same species.
authors.affiliation: State Key Laboratory for Agrobiotechnology and Department of Microbiology, China Agricultural University, 100094, Beijing, China.
authors.forename: H X
authors.initials: HX
authors.lastname: Wang
authors.forename: T B
authors.initials: TB
authors.lastname: Ng
mesh_terms: D000595:Amino Acid Sequence; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D048690:Fruiting Bodies, Fungal / Q000201:enzymology*; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors; D006863:Hydrogen-Ion Concentration; D042845:Laccase / Q000737:chemistry / Q000302:isolation & purification*; D008970:Molecular Weight; D020076:Pleurotus / Q000201:enzymology*; D017386:Sequence Homology, Amino Acid; D013696:Temperature
chemical_list: D042845:Laccase; D054303:HIV Reverse Transcriptase