title: Discovery of a eukaryotic pyrroloquinoline quinone-dependent oxidoreductase belonging to a new auxiliary activity family in the database of carbohydrate-active enzymes.
abstract: Pyrroloquinoline quinone (PQQ) is a redox cofactor utilized by a number of prokaryotic dehydrogenases. Not all prokaryotic organisms are capable of synthesizing PQQ, even though it plays important roles in the growth and development of many organisms, including humans. The existence of PQQ-dependent enzymes in eukaryotes has been suggested based on homology studies or the presence of PQQ-binding motifs, but there has been no evidence that such enzymes utilize PQQ as a redox cofactor. However, during our studies of hemoproteins, we fortuitously discovered a novel PQQ-dependent sugar oxidoreductase in a mushroom, the basidiomycete Coprinopsis cinerea. The enzyme protein has a signal peptide for extracellular secretion and a domain for adsorption on cellulose, in addition to the PQQ-dependent sugar dehydrogenase and cytochrome domains. Although this enzyme shows low amino acid sequence homology with known PQQ-dependent enzymes, it strongly binds PQQ and shows PQQ-dependent activity. BLAST search uncovered the existence of many genes encoding homologous proteins in bacteria, archaea, amoebozoa, and fungi, and phylogenetic analysis suggested that these quinoproteins may be members of a new family that is widely distributed not only in prokaryotes, but also in eukaryotes.
authors.affiliation: Department of Biomaterials Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan.
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Matsumura
authors.affiliation: Department of Environmental and Natural Resource Science, Tokyo University of Agriculture and Technology, Tokyo, Japan.
authors.forename: Kiwamu
authors.initials: K
authors.lastname: Umezawa
authors.affiliation: Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Tokyo, Japan.
authors.forename: Kouta
authors.initials: K
authors.lastname: Takeda
authors.affiliation: Department of Biomaterials Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan.
authors.forename: Naohisa
authors.initials: N
authors.lastname: Sugimoto
authors.affiliation: Department of Biomaterials Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan; Advanced Low Carbon Technology Research and Development Program (ALCA), Japan Science and Technology Agency (JST), Tokyo, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Ishida
authors.affiliation: Department of Biomaterials Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Samejima
authors.affiliation: Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Tokyo, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ohno
authors.affiliation: Department of Environmental and Natural Resource Science, Tokyo University of Agriculture and Technology, Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoshida
authors.affiliation: Department of Biomaterials Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan; Advanced Low Carbon Technology Research and Development Program (ALCA), Japan Science and Technology Agency (JST), Tokyo, Japan.
authors.forename: Kiyohiko
authors.initials: K
authors.lastname: Igarashi
authors.affiliation: Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Tokyo, Japan; Advanced Low Carbon Technology Research and Development Program (ALCA), Japan Science and Technology Agency (JST), Tokyo, Japan.
authors.forename: Nobuhumi
authors.initials: N
authors.lastname: Nakamura
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001487:Basidiomycota / Q000201:enzymology; D002151:Calorimetry; D017931:DNA Primers; D030562:Databases, Protein; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000737:chemistry* / Q000235:genetics; D045542:PQQ Cofactor / Q000737:chemistry*; D010802:Phylogeny; D010843:Pichia / Q000235:genetics; D017386:Sequence Homology, Amino Acid
chemical_list: D017931:DNA Primers; D045542:PQQ Cofactor; D010088:Oxidoreductases