title: Isolation and Characterization of a Ubiquitin-Like Ribonuclease from the Cultured Deep Root Mushroom, Oudemansiella radicata (Higher Basidiomycetes).
abstract: The isolation of a novel 13.5-kDa ribonuclease, displaying a ubiquitin-like inner peptide sequence, from dried fruiting bodies of the cultured mushroom Oudemansiella radicata (Relhan: Fr.) Singer (=Xerula radicata) is reported. The purification protocol deployed encompassed sequentially, cation/anion exchange chromatography on CM-cellulose, DEAE-cellulose and SP-Sepharose, and FPLC-gel filtration on a Superdex 75 column. The purified enzyme manifested optimum activity at 70 °C and pH 4.6, respectively. The activity of the RNase was inhibited by the majority of metal ions tested, especially Al3+, Hg2+, and Cd2+ ions, but was promoted by K+ ions. It exhibited the highest ribonucleolytic activity toward poly (C), lower activity toward poly (G), and negligible activity toward poly (U) and poly (A). Compared with mushroom ubiquitin-like RNases reported earlier, O. radicata RNase possesses a larger molecular mass, distinctive chromatographic behavior on DEAE-cellulose, a lower optimum pH, and a unique polyhomoribonucleotide specificity.
authors: State Key Laboratory for Agrobiotechnology and Department of Microbiology, China Agricultural University, Beijing, China.
authors: Qin
authors: Q
authors: Liu
authors: State Key Laboratory for Agrobiotechnology and Department of Microbiology, China Agricultural University, Beijing, China.
authors: Hao
authors: H
authors: Chen
authors: State Key Laboratory for Agrobiotechnology and Department of Microbiology, China Agricultural University, Beijing 100193, China.
authors: Hexiang
authors: H
authors: Wang
authors: School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
authors: Tzi Bun
authors: TB
authors: Ng
mesh_terms: D000363:Agaricales / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D000595:Amino Acid Sequence; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004795:Enzyme Stability; D005656:Fungal Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D008969:Molecular Sequence Data; D008970:Molecular Weight; D012260:Ribonucleases / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D016415:Sequence Alignment; D025801:Ubiquitin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D025801:Ubiquitin; D012260:Ribonucleases