Cargando…

Molecular Phylogeny and Taxonomy of the Genus Spumella (Chrysophyceae) Based on Morphological and Molecular Evidence

The genus Spumella, established by Cienkowsky in 1870, is characterized by omnivory, two (rarely three) flagella, a short stick-like structure beneath the flagella, a threadlike stalk, cell division via constriction and cyst formation. Since the first phylogenetic study of Spumella-like flagellates,...

Descripción completa

Detalles Bibliográficos
Autores principales: Jeong, Minseok, Kim, Jong Im, Nam, Seung Won, Shin, Woongghi
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8577464/
https://www.ncbi.nlm.nih.gov/pubmed/34764972
http://dx.doi.org/10.3389/fpls.2021.758067
_version_ 1784596064905461760
author Jeong, Minseok
Kim, Jong Im
Nam, Seung Won
Shin, Woongghi
author_facet Jeong, Minseok
Kim, Jong Im
Nam, Seung Won
Shin, Woongghi
author_sort Jeong, Minseok
collection PubMed
description The genus Spumella, established by Cienkowsky in 1870, is characterized by omnivory, two (rarely three) flagella, a short stick-like structure beneath the flagella, a threadlike stalk, cell division via constriction and cyst formation. Since the first phylogenetic study of Spumella-like flagellates, their paraphyly has consistently been shown, with separation into several genera. More recently, Spumella was carefully investigated using molecular and morphological data to propose seven new species. Classification of this genus and knowledge of its species diversity remain limited because Spumella-like flagellates are extremely difficult to identify based on limited morphological characters. To understand the phylogeny and taxonomy of Spumella, we analyzed molecular and morphological data from 47 strains, including 18 strains isolated from Korean ponds or swamps. Nuclear SSU, ITS and LSU rDNA data were used for maximum likelihood and Bayesian analyses. The molecular data divided the strains into 15 clades, including seven new lineages, each with unique molecular signatures for nuclear SSU rRNA from the E23-2 to E23-5 domains, the spacer between the E23-8 and E23-9 domains of the V4 region and domain 29 of the V5 region. Our results revealed increased species diversity in Spumella. In contrast to the molecular phylogeny results, the taxa showed very similar cell morphologies, suggesting morphological convergence into simple nanoflagellates to enable heterotrophy. Three new species produced stomatocysts in culture. Aspects of stomatocyst morphology, including collar structure, surface ornamentation, and cyst shape, were very useful in differentiating the three species. The general ultrastructure of Spumella bureschii strain Baekdongje012018B8 and S. benthica strain Hwarim032418A5 showed the typical chrysophyte form for the leucoplast, a vestigial chloroplast surrounded by four envelope membranes, supporting the hypothesis that Spumella evolved from a phototroph to a heterotroph via the loss of its photosynthetic ability. Seven new species are proposed: S. benthica, S. communis, S. longicolla, S. oblata, S. rotundata, S. similis, and S. sinechrysos.
format Online
Article
Text
id pubmed-8577464
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-85774642021-11-10 Molecular Phylogeny and Taxonomy of the Genus Spumella (Chrysophyceae) Based on Morphological and Molecular Evidence Jeong, Minseok Kim, Jong Im Nam, Seung Won Shin, Woongghi Front Plant Sci Plant Science The genus Spumella, established by Cienkowsky in 1870, is characterized by omnivory, two (rarely three) flagella, a short stick-like structure beneath the flagella, a threadlike stalk, cell division via constriction and cyst formation. Since the first phylogenetic study of Spumella-like flagellates, their paraphyly has consistently been shown, with separation into several genera. More recently, Spumella was carefully investigated using molecular and morphological data to propose seven new species. Classification of this genus and knowledge of its species diversity remain limited because Spumella-like flagellates are extremely difficult to identify based on limited morphological characters. To understand the phylogeny and taxonomy of Spumella, we analyzed molecular and morphological data from 47 strains, including 18 strains isolated from Korean ponds or swamps. Nuclear SSU, ITS and LSU rDNA data were used for maximum likelihood and Bayesian analyses. The molecular data divided the strains into 15 clades, including seven new lineages, each with unique molecular signatures for nuclear SSU rRNA from the E23-2 to E23-5 domains, the spacer between the E23-8 and E23-9 domains of the V4 region and domain 29 of the V5 region. Our results revealed increased species diversity in Spumella. In contrast to the molecular phylogeny results, the taxa showed very similar cell morphologies, suggesting morphological convergence into simple nanoflagellates to enable heterotrophy. Three new species produced stomatocysts in culture. Aspects of stomatocyst morphology, including collar structure, surface ornamentation, and cyst shape, were very useful in differentiating the three species. The general ultrastructure of Spumella bureschii strain Baekdongje012018B8 and S. benthica strain Hwarim032418A5 showed the typical chrysophyte form for the leucoplast, a vestigial chloroplast surrounded by four envelope membranes, supporting the hypothesis that Spumella evolved from a phototroph to a heterotroph via the loss of its photosynthetic ability. Seven new species are proposed: S. benthica, S. communis, S. longicolla, S. oblata, S. rotundata, S. similis, and S. sinechrysos. Frontiers Media S.A. 2021-10-26 /pmc/articles/PMC8577464/ /pubmed/34764972 http://dx.doi.org/10.3389/fpls.2021.758067 Text en Copyright © 2021 Jeong, Kim, Nam and Shin. https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Plant Science
Jeong, Minseok
Kim, Jong Im
Nam, Seung Won
Shin, Woongghi
Molecular Phylogeny and Taxonomy of the Genus Spumella (Chrysophyceae) Based on Morphological and Molecular Evidence
title Molecular Phylogeny and Taxonomy of the Genus Spumella (Chrysophyceae) Based on Morphological and Molecular Evidence
title_full Molecular Phylogeny and Taxonomy of the Genus Spumella (Chrysophyceae) Based on Morphological and Molecular Evidence
title_fullStr Molecular Phylogeny and Taxonomy of the Genus Spumella (Chrysophyceae) Based on Morphological and Molecular Evidence
title_full_unstemmed Molecular Phylogeny and Taxonomy of the Genus Spumella (Chrysophyceae) Based on Morphological and Molecular Evidence
title_short Molecular Phylogeny and Taxonomy of the Genus Spumella (Chrysophyceae) Based on Morphological and Molecular Evidence
title_sort molecular phylogeny and taxonomy of the genus spumella (chrysophyceae) based on morphological and molecular evidence
topic Plant Science
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8577464/
https://www.ncbi.nlm.nih.gov/pubmed/34764972
http://dx.doi.org/10.3389/fpls.2021.758067
work_keys_str_mv AT jeongminseok molecularphylogenyandtaxonomyofthegenusspumellachrysophyceaebasedonmorphologicalandmolecularevidence
AT kimjongim molecularphylogenyandtaxonomyofthegenusspumellachrysophyceaebasedonmorphologicalandmolecularevidence
AT namseungwon molecularphylogenyandtaxonomyofthegenusspumellachrysophyceaebasedonmorphologicalandmolecularevidence
AT shinwoongghi molecularphylogenyandtaxonomyofthegenusspumellachrysophyceaebasedonmorphologicalandmolecularevidence