title: Delineation of six species of the primitive algal genus Glaucocystis based on in situ ultrastructural characteristics.
abstract: The field of microbiology was established in the 17(th) century upon the discovery of microorganisms by Antonie van Leeuwenhoek using a single-lens microscope. Now, the detailed ultrastructures of microorganisms can be elucidated in situ using three-dimensional electron microscopy. Since the availability of electron microscopy, the taxonomy of microscopic organisms has entered a new era. Here, we established a new taxonomic system of the primitive algal genus Glaucocystis (Glaucophyta) using a new-generation electron microscopic methodology: ultra-high-voltage electron microscopy (UHVEM) and field-emission scanning electron microscopy (FE-SEM). Various globally distributed Glaucocystis strains were delineated into six species, based on differences in in situ ultrastructural features of the protoplast periphery under UHVEM tomography and in the mother cell wall by FE-SEM, as well as differences in the light microscopic characteristics and molecular phylogenetic results. The present work on Glaucocystis provides a model case of new-generation taxonomy.
authors.affiliation: Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1 Mihogaoka, Ibaraki, Osaka, 567-0047, Japan.
authors.forename: Tomoki
authors.initials: T
authors.lastname: Nishida
authors.affiliation: Department of Botany, National Science Museum, 4-1-1 Amakubo, Tsukuba, Ibaraki, 305-0005, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Tuji
authors.affiliation: Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Chieko
authors.initials: C
authors.lastname: Saito
authors.affiliation: Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Matsuzaki
authors.affiliation: RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
authors.forename: Mayuko
authors.initials: M
authors.lastname: Sato
authors.affiliation: RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
authors.forename: Kiminori
authors.initials: K
authors.lastname: Toyooka
authors.affiliation: Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Yasuda
authors.affiliation: Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1 Mihogaoka, Ibaraki, Osaka, 567-0047, Japan.
authors.forename: Hisayoshi
authors.initials: H
authors.lastname: Nozaki
mesh_terms: D021901:DNA, Intergenic / Q000737:chemistry / Q000235:genetics; D058108:Glaucophyta / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics / Q000648:ultrastructure*; D009690:Nucleic Acid Conformation; D010802:Phylogeny; D013045:Species Specificity; D014054:Tomography
chemical_list: D021901:DNA, Intergenic