title: A laccase with antiproliferative activity against tumor cells from an edible mushroom, white common Agrocybe cylindracea.
abstract: A laccase, with HIV-1 reverse transcriptase inhibitory activity (IC(50)=12.7 μM) and antiproliferative activity against HepG2 cells (IC(50)=5.6 μM) and MCF7 cells (IC(50)=6.5 μM), was purified from fresh fruiting bodies of the edible white common Agrocybe cylindracea mushroom. The laccase, which had a novel N-terminal sequence, displayed a molecular mass of 58 kDa within the range reported for most other mushroom laccases. The purification protocol entailed ion exchange chromatography on DEAE-cellulose, SP-Sepharose, and Q-Sepharose and gel filtration on Superdex 75. The laccase was adsorbed on DEAE-cellulose and Q-Sepharose, but unadsorbed on SP-Sepharose. Its optimum pH was pH 3-4 and its optimum temperature was 50°C. The activity of the isolated laccase differed from one substrate to another. The ranking was ABTS>N,N-dimethyl-1,4-phenylenediamine>hydroquinone>catechol>2-methylcatechol>pyrogallol.
authors.affiliation: State Key Laboratory for Agrobiotechnology, Department of Microbiology, China Agricultural University, Beijing, China.
authors.forename: D D
authors.initials: DD
authors.lastname: Hu
authors.forename: R Y
authors.initials: RY
authors.lastname: Zhang
authors.forename: G Q
authors.initials: GQ
authors.lastname: Zhang
authors.forename: H X
authors.initials: HX
authors.lastname: Wang
authors.forename: T B
authors.initials: TB
authors.lastname: Ng
mesh_terms: D055362:Agrocybe / Q000201:enzymology*; D000595:Amino Acid Sequence; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D048690:Fruiting Bodies, Fungal / Q000201:enzymology; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D042845:Laccase / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology*; D008970:Molecular Weight; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D042845:Laccase; D054303:HIV Reverse Transcriptase