title: Application of the phylogenetic species concept to Wallemia sebi from house dust and indoor air revealed by multi-locus genealogical concordance.
abstract: A worldwide survey of Wallemia occurring in house dust and indoor air was conducted. The isolated strains were identified as W. sebi and W. muriae. Previous studies suggested that the W. sebi phylogenetic clade contained cryptic species but conclusive evidence was lacking because only the internal transcribed spacer (ITS) marker was analyzed. The ITS and four protein-coding genes (MCM7, RPB1, RPB2, and TSR1) were sequenced for 85 isolates. Based on an initial neighbor joining analysis of the concatenated genes, W. muriae remained monophyletic but four clades were found in W. sebi, which we designated as W. sebi clades 1, 2, 3, and 4. We hypothesized that these clades represent distinct phylogenetic species within the Wallemia sebi species complex (WSSC). We then conducted multiple phylogenetic analyses and demonstrated genealogical concordance, which supports the existence of four phylogenetic species within the WSSC. Geographically, W. muriae was only found in Europe, W. sebi clade 3 was only found in Canada, W. sebi clade 4 was found in subtropical regions, while W. sebi clade 1 and 2 were found worldwide. Haplotype analysis showed that W. sebi clades 1 and 2 had multiple haplotypes while W. sebi clades 3 and 4 had one haplotype and may have been under sampled. We describe W. sebi clades 2, 3, and 4 as new species in a companion study.
authors: Department of Biology, Faculty of Science, University of Ottawa, Ottawa, Ontario, Canada; Biodiversity (Mycology), Eastern Cereal and Oilseed Research Centre, Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada.
authors: Hai D T
authors: HD
authors: Nguyen
authors: Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia.
authors: Sašo
authors: S
authors: Jančič
authors: CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands.
authors: Martin
authors: M
authors: Meijer
authors: Biodiversity (Mycology), Eastern Cereal and Oilseed Research Centre, Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada.
authors: Joey B
authors: JB
authors: Tanney
authors: Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia.
authors: Polona
authors: P
authors: Zalar
authors: Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia.
authors: Nina
authors: N
authors: Gunde-Cimerman
authors: Department of Biology, Faculty of Science, University of Ottawa, Ottawa, Ontario, Canada; Biodiversity (Mycology), Eastern Cereal and Oilseed Research Centre, Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada.
authors: Keith A
authors: KA
authors: Seifert
mesh_terms: D000391:Air Microbiology; D016902:Air Pollution, Indoor; D001487:Basidiomycota / Q000145:classification* / Q000235:genetics*; D004391:Dust; D005800:Genes, Fungal; D056426:Genetic Loci; D005819:Genetic Markers; D014644:Genetic Variation; D005843:Geography; D058885:Multilocus Sequence Typing; D010802:Phylogeny; D058974:Phylogeography
chemical_list: D004391:Dust; D005819:Genetic Markers