title: A novel serine protease with caspase- and legumain-like activities from edible basidiomycete Flammulina velutipes.
abstract: A serine protease with caspase- and legumain-like activities from basidiocarps of the edible basidiomycete Flammulina velutipes was characterized. The protease was purified to near homogeneity by three steps of chromatography using acetyl-Tyr-Val-Ala-Asp-4-methylcoumaryl-7-amide (Ac-YVAD-MCA) as a substrate. The enzyme was termed FvSerP (F. velutipes serine protease). This enzyme activity was completely inhibited by the caspase-specific inhibitor, Ac-YVAD-CHO, as well as moderately inhibited by serine protease inhibitors. Based on the N-terminal sequence, the cDNA of FvSerP was identified. The deduced protease sequence was a peptide composed of 325 amino acids with a molecular mass of 34.5 kDa. The amino acid sequence of FvSerP showed similarity to neither caspases nor to the plant subtilisin-like serine protease with caspase-like activity called saspase. FvSerP shared identity to the functionally unknown genes from class of Agaricomycetes, with similarity to the peptidase S41 domain of a serine protease. It was thus concluded that this enzyme is likely a novel serine protease with caspase- and legumain-like activities belonging to the peptidase S41 family and distributed in the class Agaricomycetes. This enzyme possibly functions in autolysis, a type of programmed cell death that occurs in the later stages of development of basidiocarps with reference to their enzymatic functions.
authors.affiliation: Department of Biological Science, Faculty of Science, Shizuoka University, 422-8529 Shizuoka, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Iketani
authors.forename: Mayumi
authors.initials: M
authors.lastname: Nakamura
authors.forename: Yuya
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Koichiro
authors.initials: K
authors.lastname: Awai
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Shioi
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001487:Basidiomycota / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D020169:Caspases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D012697:Serine Endopeptidases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000099240:Asparaginyl Endopeptidase
chemical_list: D020169:Caspases; D003546:Cysteine Endopeptidases; D005656:Fungal Proteins; D012697:Serine Endopeptidases; D000099240:Asparaginyl Endopeptidase