title: Molecular characterization of the basidiomycete isolate Nematoloma frowardii b19 and its manganese peroxidase places the fungus in the corticioid genus Phlebia.
abstract: The basidiomycete isolate b19, originally identified by morphological characteristics of the fruiting body as Nematoloma frowardii, efficiently produces manganese peroxidase (MNP) and is used for degradation of natural, persistent aromatic polymers (lignin, humic acids and brown coal components). The N. frowardii MNP has shown good activity in conversion of xenobiotic compounds such as polycyclic hydrocarbons and trinitrotoluene. However, this biotechnologically promising fungus has not previously been studied at the molecular biology level. We show here that according to the molecular characterization of its main MNP isozyme, Nf b19 MNP2, and partial sequencing of its MNP3-, three lignin peroxidase- and two laccase-encoding genes, and the gene encoding the ribosomal SSU 18S RNA, that the fungus has a close phylogenetic relationship to the white-rot basidiomycete Phlebia radiata (Fr.). Ribosomal internal transcribed spacer (ITS) sequence (ITS1+5.8S+ITS2) phylogeny reclassifies Nf b19 as a possible representative of a new species of the genus Phlebia, nearest to the Phlebia acerina clade. The genus Phlebia belongs to a completely different family (Corticiaceae) and order (Aphyllophorales) within the phylum Basidiomycota than the genus Nematoloma, which is classified in the order Agaricales, family Strophariaceae. Our results thus indicate a need for systematic re-identification of the previously named N. frowardii isolate b19.
authors.affiliation: Laboratory of Fungal Biotechnology, Department of Applied Chemistry and Microbiology, Division of Microbiology, University of Helsinki, FIN-00014 Helsinki, Finland.
authors.forename: Kristiina S
authors.initials: KS
authors.lastname: Hildén
authors.affiliation: Laboratory of Fungal Biotechnology, Department of Applied Chemistry and Microbiology, Division of Microbiology, University of Helsinki, FIN-00014 Helsinki, Finland.
authors.forename: Ralf
authors.initials: R
authors.lastname: Bortfeldt
authors.affiliation: Laboratory of Fungal Biotechnology, Department of Applied Chemistry and Microbiology, Division of Microbiology, University of Helsinki, FIN-00014 Helsinki, Finland.
authors.forename: Martin
authors.initials: M
authors.lastname: Hofrichter
authors.affiliation: Laboratory of Fungal Biotechnology, Department of Applied Chemistry and Microbiology, Division of Microbiology, University of Helsinki, FIN-00014 Helsinki, Finland.
authors.forename: Annele
authors.initials: A
authors.lastname: Hatakka
authors.affiliation: Laboratory of Fungal Biotechnology, Department of Applied Chemistry and Microbiology, Division of Microbiology, University of Helsinki, FIN-00014 Helsinki, Finland.
authors.forename: Taina K
authors.initials: TK
authors.lastname: Lundell
mesh_terms: D000363:Agaricales / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D000595:Amino Acid Sequence; D001487:Basidiomycota / Q000145:classification / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010544:Peroxidases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D005656:Fungal Proteins; D012337:RNA, Ribosomal, 18S; D010544:Peroxidases; C051129:manganese peroxidase