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Graf L, Yang EC, Han KY, Küpper FC, Benes KM, Oyadomari JK, Herbert RJH, Verbruggen H, Wetherbee R, Andersen RA, Yoon HS. Multigene Phylogeny, Morphological Observation and Re-examination of the Literature Lead to the Description of the Phaeosacciophyceae Classis Nova and Four New Species of the Heterokontophyta SI Clade. Protist 2020; 171:125781. [PMID: 33278705 DOI: 10.1016/j.protis.2020.125781] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 10/05/2020] [Accepted: 10/05/2020] [Indexed: 01/19/2023]
Abstract
The relationships among the Aurearenophyceae, Phaeothamniophyceae, Phaeophyceae and Xanthophyceae lineages of the Heterokontophyta SI clade are not well known. By adding previously unexamined taxa related to these classes in a five gene phylogeny (SSU rRNA, atpB, psaA, psaB, rbcL), we recovered an assemblage of taxa previously unrecognized. We propose the class Phaeosacciophyceae class. nov., that includes Phaeosaccion collinsii, Phaeosaccion multiseriatum sp. nov., Phaeosaccion okellyi sp. nov., Antarctosaccion applanatum, Tetrasporopsis fuscescens, Tetrasporopsis moei sp. nov., and Psammochrysis cassiotisii gen. & sp. nov. We re-examine the literature for Chrysomeris, Nematochrysis, Chrysowaernella and the invalid name "Giraudyopsis" and conclude some taxa in previous studies are misidentified or misnamed, i.e. Chrysomeris and Chrysowaernella, respectively. We also show that Nematochrysis sessilis var. vectensis and Nematochrysis hieroglyphica may belong in the recently described class Chrysoparadoxophyceae. The phylogenetic relationships of Phaeobotrys solitaria and Pleurochloridella botrydiopsis are not clearly resolved, but they branch near the Xanthophyceae. Here we describe a new class Phaeosacciophyceae, a new order Phaeosacciales, a new family Tetrasporopsidaceae, a new genus Psammochrysis and four new species.
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Affiliation(s)
- Louis Graf
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Eun Chan Yang
- Marine Ecosystem Research Center, Korea Institute of Ocean Science and Technology, Busan 49111, Republic of Korea
| | - Kwi Young Han
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Frithjof C Küpper
- School of Biological Sciences, Cruickshank Bldg, University of Aberdeen, St. Machar Drive, Aberdeen AB24 3UU, Scotland, UK; Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, Scotland, UK
| | - Kylla M Benes
- Davidson Honors College, University of Montana, Missoula, MT 59812, USA
| | - Jason K Oyadomari
- Suomi College of Arts and Sciences, Finlandia University, Hancock, MI 49930, USA
| | - Roger J H Herbert
- Department of Life and Environmental Sciences, Bournemouth University, Poole, Dorset BH12 5BB, UK
| | - Heroen Verbruggen
- School of BioSciences, University of Melbourne, Victoria 3010, Australia
| | - Richard Wetherbee
- School of BioSciences, University of Melbourne, Victoria 3010, Australia
| | - Robert A Andersen
- Friday Harbor Laboratories, University of Washington, Friday Harbor, WA 98250, USA.
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea.
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Stoyneva-Gärtner M, Stoykova P, Uzunov B, Dincheva I, Atanassov I, Draganova P, Borisova C, Gärtner G. Carotenoids in five aeroterrestrial strains fromVischeria/Eustigmatosgroup: updating the pigment pattern of Eustigmatophyceae. BIOTECHNOL BIOTEC EQ 2019. [DOI: 10.1080/13102818.2018.1562984] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Affiliation(s)
- Maya Stoyneva-Gärtner
- Department of Botany, Faculty of Biology, Sofia University “St Kliment Ohridski”, Sofia, Bulgaria
| | - Petya Stoykova
- Functional Genetics Legumes Group, AgroBioInstitute, Agricultural Academy, Sofia, Bulgaria
| | - Blagoy Uzunov
- Department of Botany, Faculty of Biology, Sofia University “St Kliment Ohridski”, Sofia, Bulgaria
| | - Ivayla Dincheva
- Plant Genetic Resources Group, AgroBioInstitute, Agricultural Academy, Sofia, Bulgaria
| | - Ivan Atanassov
- Molecular Genetics Group, AgroBioInstitute, Agricultural Academy, Sofia, Bulgaria
| | - Petya Draganova
- Department of Botany, Faculty of Biology, Sofia University “St Kliment Ohridski”, Sofia, Bulgaria
| | - Cvetanka Borisova
- Department of Botany, Faculty of Biology, Sofia University “St Kliment Ohridski”, Sofia, Bulgaria
| | - Georg Gärtner
- Institute of Botany, Faculty of Biology, University of Innsbruck, Innsbruck, Austria
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Microheliella maris (Microhelida ord. n.), an Ultrastructurally Highly Distinctive New Axopodial Protist Species and Genus, and the Unity of Phylum Heliozoa. Protist 2012; 163:356-88. [DOI: 10.1016/j.protis.2011.10.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 10/09/2011] [Indexed: 11/30/2022]
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Kai A, Yoshii Y, Nakayama T, Inouye I. Aurearenophyceae classis nova, a New Class of Heterokontophyta Based on a New Marine Unicellular Alga Aurearena cruciata gen. et sp. nov. Inhabiting Sandy Beaches. Protist 2008; 159:435-57. [DOI: 10.1016/j.protis.2007.12.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Accepted: 12/29/2007] [Indexed: 10/22/2022]
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Cavalier-Smith T, Chao EEY. Phylogeny and Megasystematics of Phagotrophic Heterokonts (Kingdom Chromista). J Mol Evol 2006; 62:388-420. [PMID: 16557340 DOI: 10.1007/s00239-004-0353-8] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2004] [Accepted: 09/21/2005] [Indexed: 10/24/2022]
Abstract
Heterokonts are evolutionarily important as the most nutritionally diverse eukaryote supergroup and the most species-rich branch of the eukaryotic kingdom Chromista. Ancestrally photosynthetic/phagotrophic algae (mixotrophs), they include several ecologically important purely heterotrophic lineages, all grossly understudied phylogenetically and of uncertain relationships. We sequenced 18S rRNA genes from 14 phagotrophic non-photosynthetic heterokonts and a probable Ochromonas, performed phylogenetic analysis of 210-430 Heterokonta, and revised higher classification of Heterokonta and its three phyla: the predominantly photosynthetic Ochrophyta; the non-photosynthetic Pseudofungi; and Bigyra (now comprising subphyla Opalozoa, Bicoecia, Sagenista). The deepest heterokont divergence is apparently between Bigyra, as revised here, and Ochrophyta/Pseudofungi. We found a third universal heterokont signature sequence, and deduce three independent losses of ciliary hairs, several of 1-2 cilia, 10 of photosynthesis, but perhaps only two plastid losses. In Ochrophyta, heterotrophic Oikomonas is sister to the photosynthetic Chrysamoeba, whilst the abundant freshwater predator Spumella is biphyletic; neither clade is specifically related to Paraphysomonas, indicating four losses of photosynthesis by chrysomonads. Sister to Chrysomonadea (Chrysophyceae) is Picophagea cl. nov. (Picophagus, Chlamydomyxa). The diatom-parasite Pirsonia belongs in Pseudofungi. Heliozoan-like actinophryids (e.g. Actinosphaerium) are Opalozoa, not related to pedinellids within Hypogyristea cl. nov. of Ochrophyta as once thought. The zooflagellate class Bicoecea (perhaps the ancestral phenotype of Bigyra) is unexpectedly diverse and a major focus of our study. We describe four new biciliate bicoecean genera and five new species: Nerada mexicana, Labromonas fenchelii (=Pseudobodo tremulans sensu Fenchel), Boroka karpovii (=P. tremulans sensu Karpov), Anoeca atlantica and Cafeteria mylnikovii; several cultures were previously misidentified as Pseudobodo tremulans. Nerada and the uniciliate Paramonas are related to Siluania and Adriamonas; this clade (Pseudodendromonadales emend.) is probably sister to Bicosoeca. Genetically diverse Caecitellus is probably related to Anoeca, Symbiomonas and Cafeteria (collectively Anoecales emend.). Boroka is sister to Pseudodendromonadales/Bicoecales/Anoecales. Placidiales are probably divergent bicoeceans (the GenBank Placidia sequence is a basidiomycete/heterokont chimaera). Two GenBank 'opalinid' sequences are fungal; Pseudopirsonia is cercozoan; two previous GenBank 'Caecitellus' sequences are Adriamonas.
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Vickerman K, Appleton PL, Clarke KJ, Moreira D. Aurigamonas solis n. gen., n. sp., a soil-dwelling predator with unusual helioflagellate organisation and belonging to a novel clade within the Cercozoa. Protist 2005; 156:335-54. [PMID: 16325545 DOI: 10.1016/j.protis.2005.07.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Accepted: 07/15/2005] [Indexed: 11/26/2022]
Abstract
A flagellate predator, Aurigamonas solis n. gen., n. sp., with numerous radiating axopodia-like appendages, has been isolated in culture from soils. Despite its heliozoan-like appearance, Aurigamonas is not a sit-and-wait predator but a mobile hunter and its stiff appendages are not microtubule-supported axopodia but elongate haptopodia, each supported by a cylindrical core of microfilaments and bearing at its capitate tip a single extrusome-like body (haptosome). Prey flagellates are trapped on the sticky tips of the haptopodia and a large funnel-shaped pseudopodium then emerges to engulf the prey or suck out part of it for internal digestion. Pseudopodial contact is accompanied by killing, possibly as a result of the injection of spicules by the predator. Cytoplasmic haptosomes appear to induce formation of a haptopodium on making contact with the plasma membrane. Propulsion of the organism along the substratum is effected by beating of a long trailing flagellum, the short and inconspicuous second flagellum lacks motility. Small subunit rDNA sequencing shows that Aurigamonas arose within the Cercozoa. Its closest relatives are Cercobodo agilis and several flagellates currently known only as environmental sequences. This conclusion is supported further by the presence of only a single amino acid insertion in the polyubiquitin sequence of Aurigamonas solis.
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Affiliation(s)
- Keith Vickerman
- Division of Environmental and Evolutionary Biology, University of Glasgow, Glasgow G12 8QQ, UK.
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Andersen RA. Biology and systematics of heterokont and haptophyte algae. AMERICAN JOURNAL OF BOTANY 2004; 91:1508-1522. [PMID: 21652306 DOI: 10.3732/ajb.91.10.1508] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this paper, I review what is currently known of phylogenetic relationships of heterokont and haptophyte algae. Heterokont algae are a monophyletic group that is classified into 17 classes and represents a diverse group of marine, freshwater, and terrestrial algae. Classes are distinguished by morphology, chloroplast pigments, ultrastructural features, and gene sequence data. Electron microscopy and molecular biology have contributed significantly to our understanding of their evolutionary relationships, but even today class relationships are poorly understood. Haptophyte algae are a second monophyletic group that consists of two classes of predominately marine phytoplankton. The closest relatives of the haptophytes are currently unknown, but recent evidence indicates they may be part of a large assemblage (chromalveolates) that includes heterokont algae and other stramenopiles, alveolates, and cryptophytes. Heterokont and haptophyte algae are important primary producers in aquatic habitats, and they are probably the primary carbon source for petroleum products (crude oil, natural gas).
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Affiliation(s)
- Robert A Andersen
- Bigelow Laboratory for Ocean Sciences, P.O. Box 475, West Boothbay Harbor, Maine 04575 USA
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Cavalier-Smith T. Genomic reduction and evolution of novel genetic membranes and protein-targeting machinery in eukaryote-eukaryote chimaeras (meta-algae). Philos Trans R Soc Lond B Biol Sci 2003; 358:109-33; discussion 133-4. [PMID: 12594921 PMCID: PMC1693104 DOI: 10.1098/rstb.2002.1194] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Chloroplasts originated just once, from cyanobacteria enslaved by a biciliate protozoan to form the plant kingdom (green plants, red and glaucophyte algae), but subsequently, were laterally transferred to other lineages to form eukaryote-eukaryote chimaeras or meta-algae. This process of secondary symbiogenesis (permanent merger of two phylogenetically distinct eukaryote cells) has left remarkable traces of its evolutionary role in the more complex topology of the membranes surrounding all non-plant (meta-algal) chloroplasts. It took place twice, soon after green and red algae diverged over 550 Myr ago to form two independent major branches of the eukaryotic tree (chromalveolates and cabozoa), comprising both meta-algae and numerous secondarily non-photosynthetic lineages. In both cases, enslavement probably began by evolving a novel targeting of endomembrane vesicles to the perialgal vacuole to implant host porter proteins for extracting photosynthate. Chromalveolates arose by such enslavement of a unicellular red alga and evolution of chlorophyll c to form the kingdom Chromista and protozoan infrakingdom Alveolata, which diverged from the ancestral chromalveolate chimaera. Cabozoa arose when the common ancestor of euglenoids and cercozoan chlorarachnean algae enslaved a tetraphyte green alga with chlorophyll a and b. I suggest that in cabozoa the endomembrane vesicles originally budded from the Golgi, whereas in chromalveolates they budded from the endoplasmic reticulum (ER) independently of Golgi-targeted vesicles, presenting a potentially novel target for drugs against alveolate Sporozoa such as malaria parasites and Toxoplasma. These hypothetical ER-derived vesicles mediated fusion of the perialgal vacuole and rough ER (RER) in the ancestral chromist, placing the former red alga within the RER lumen. Subsequently, this chimaera diverged to form cryptomonads, which retained the red algal nucleus as a nucleomorph (NM) with approximately 464 protein-coding genes (30 encoding plastid proteins) and a red or blue phycobiliprotein antenna pigment, and the chromobiotes (heterokonts and haptophytes), which lost phycobilins and evolved the brown carotenoid fucoxanthin that colours brown seaweeds, diatoms and haptophytes. Chromobiotes transferred the 30 genes to the nucleus and lost the NM genome and nuclear-pore complexes, but retained its membrane as the periplastid reticulum (PPR), putatively the phospholipid factory of the periplastid space (former algal cytoplasm), as did the ancestral alveolate independently. The chlorarachnean NM has three minute chromosomes bearing approximately 300 genes riddled with pygmy introns. I propose that the periplastid membrane (PPM, the former algal plasma membrane) of chromalveolates, and possibly chlorarachneans, grows by fusion of vesicles emanating from the NM envelope or PPR. Dinoflagellates and euglenoids independently lost the PPM and PPR (after diverging from Sporozoa and chlorarachneans, respectively) and evolved triple chloroplast envelopes comprising the original plant double envelope and an extra outermost membrane, the EM, derived from the perialgal vacuole. In all metaalgae most chloroplast proteins are coded by nuclear genes and enter the chloroplast by using bipartite targeting sequences--an upstream signal sequence for entering the ER and a downstream chloroplast transit sequence. I present a new theory for the four-fold diversification of the chloroplast OM protein translocon following its insertion into the PPM to facilitate protein translocation across it (of both periplastid and plastid proteins). I discuss evidence from genome sequencing and other sources on the contrasting modes of protein targeting, cellular integration, and evolution of these two major lineages of eukaryote "cells within cells". They also provide powerful evidence for natural selection's effectiveness in eliminating most functionless DNA and therefore of a universally useful non-genic function for nuclear non-coding DNA, i.e. most DNA in the biosphere, and dramatic examples of genomic reduction. I briefly argue that chloroplast replacement in dinoflagellates, which happened at least twice, may have been evolutionarily easier than secondary symbiogenesis because parts of the chromalveolate protein-targeting machinery could have helped enslave the foreign plastids.
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Affiliation(s)
- T Cavalier-Smith
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK.
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Abstract
Nucleomorphs of cryptomonad and chlorarachnean algae are the relict, miniaturised nuclei of formerly independent red and green algae enslaved by separate eukaryote hosts over 500 million years ago. The complete 551 kb genome sequence of a cryptomonad nucleomorph confirms that cryptomonads are eukaryote-eukaryote chimeras and greatly illuminates the symbiogenetic event that created the kingdom Chromista and their alveolate protozoan sisters. Nucleomorph membranes may, like plasma membranes, be more enduring after secondary symbiogenesis than are their genomes. Partial sequences of chlorarachnean nucleomorphs indicate that genomic streamlining is limited by the mutational difficulty of removing useless introns. Nucleomorph miniaturisation emphasises that selection can dramatically reduce eukaryote genome size and eliminate most non-functional nuclear non-coding DNA. Given the differential scaling of nuclear and nucleomorph genomes with cell size, it follows that most non-coding nuclear DNA must have a bulk-sequence-independent function related to cell volume.
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Affiliation(s)
- T Cavalier-Smith
- Department of Zoology, University of Oxford, South Parks Road, Oxford, UK
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Abstract
Secondary endosymbiosis is the process that drives the spread of plastids (chloroplasts) from one eukaryote to another. The number of times that this has occurred and the kinds of cells involved are now becoming clear. Reconstructions of plastid history using molecular data suggest that secondary endosymbiosis is very rare and that perhaps as few as three endosymbioses have resulted in a large proportion of algal diversity. The significance of these events extends beyond photosynthesis, however, because non-photosynthetic organisms such as ciliates appear to have evolved from photosynthetic ancestors and could still harbor plastid-derived genes or relict plastids.
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Affiliation(s)
- John M Archibald
- Canadian Institute for Advanced Research, Dept Botany, University of British Columbia, Vancouver, Canada.
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Ben Ali A, De Baere R, De Wachter R, Van de Peer Y. Evolutionary relationships among heterokont algae (the autotrophic stramenopiles) based on combined analyses of small and large subunit ribosomal RNA. Protist 2002; 153:123-32. [PMID: 12125754 DOI: 10.1078/1434-4610-00091] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In order to study the phylogenetic relationships within the stramenopiles, and particularly among the heterokont algae, we have determined complete or nearly complete large-subunit ribosomal RNA sequences for different species of raphidophytes, phaeophytes, xanthophytes, chrysophytes, synurophytes and pinguiophytes. With the small- and large-subunit ribosomal RNA sequences of representatives for nearly all known groups of heterokont algae, phylogenetic trees were constructed from a concatenated alignment of both ribosomal RNAs, including more than 5,000 positions. By using different tree construction methods, inferred phylogenies showed phaeophytes and xanthophytes as sister taxa, as well as the pelagophytes and dictyochophytes, and the chrysophytes/synurophytes and eustigmatophytes. All these relationships are highly supported by bootstrap analysis. However, apart from these sister group relationships, very few other internodes are well resolved and most groups of heterokont algae seem to have diverged within a relatively short time frame.
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Sekiguchi H, Moriya M, Nakayama T, Inouye I. Vestigial chloroplasts in heterotrophic stramenopiles Pteridomonas danica and Ciliophrys infusionum (Dictyochophyceae). Protist 2002; 153:157-67. [PMID: 12125757 DOI: 10.1078/1434-4610-00094] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Two heterotrophic members of the Dictyochophyceae (stramenopiles), Pteridomonas danica and Ciliophrys infusionum, were investigated. An undescribed organelle bounded by four membranes and closely associated with the nucleus was detected in P. danica. The outermost membrane was continuous with the outer nuclear membrane. These features strongly suggested that this organelle was a vestigial chloroplast. A photosynthetic gene, rbcL, was successfully amplified by polymerase chain reaction (PCR) from P. danica and C. infusionum. These sequences were readily and well aligned with those of photosynthetic stramenopiles. Phylogenetic trees of 18S rDNA and rbcL were constructed. In all the trees obtained, P. danica and C. infusionum appeared in two different clades, the Pedinellales clade and the Ciliophryales/Rhizochromulinales clade, each of which contained photosynthetic members as well as heterotrophic members. The results indicated that the loss of photosynthetic ability occurred independently in P. danica and C. infusionum. This is the first report of the presence of a vestigial chloroplast (leucoplast) in colorless dictyochophytes.
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Affiliation(s)
- Hiroshi Sekiguchi
- Institute of Biological Sciences, University of Tsukuba, Tennoudai, Ibaraki, Japan
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Abstract
Chloroplasts originated from cyanobacteria only once, but have been laterally transferred to other lineages by symbiogenetic cell mergers. Such secondary symbiogenesis is rarer and chloroplast losses commoner than often assumed.
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Affiliation(s)
- T Cavalier-Smith
- Department of Zoology, University of Oxford, South Parks Road, OX1 3PS, Oxford, UK.
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CAVALIER-SMITH TOM. Principles of Protein and Lipid Targeting in Secondary Symbiogenesis: Euglenoid, Dinoflagellate, and Sporozoan Plastid Origins and the Eukaryote Family Tree,2. J Eukaryot Microbiol 1999; 46:347-66. [DOI: 10.1111/j.1550-7408.1999.tb04614.x] [Citation(s) in RCA: 492] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Andersen RA, Van de Peer Y, Potter D, Sexton JP, Kawachi M, LaJeunesse T. Phylogenetic analysis of the SSU rRNA from members of the Chrysophyceae. Protist 1999; 150:71-84. [PMID: 10724520 DOI: 10.1016/s1434-4610(99)70010-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The nucleotide sequence for the nuclear-encoded small subunit ribosomal RNA gene (SSU rRNA) was determined for 24 species of the Chrysophyceae sensu stricto. These sequences were aligned, using primary and secondary structure, with nine previously published sequences for the Chrysophyceae, 14 for the Synurophyceae, and five for the Eustigmatophyceae (outgroup). Data analyses were the substitution rate calibration distance method using neighbor-joining (TREECON), Kimura 2-parameter neighbor-joining method (PAUP) and the maximum parsimony method (PAUP, PHYLIP). Trees from the analyses were largely congruent, but bootstrap support was weak at many nodes. The analyses recovered clades of uniflagellate and biflagellate organisms associated with current higher level taxonomy (e.g., subclass, order). The genus Ochromonas was polyphyletic, and O. tuberculata in particular was distantly related to the other Ochromonas species in the analysis. The family Paraphysomonadaceae occupied a basal position in three of four analyses. The class Synurophyceae appeared to be embedded within the Chrysophyceae, but bootstrap support was weak (< 50%) in all analyses except the PHYLIP parsimony analysis (= 81%). It was considered premature to place the Synurophyceae back into the Chrysophyceae based upon the analysis of one gene, especially given the ultrastructural and pigment differences between the two groups, but the relationship of these two groups deserves further study.
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Affiliation(s)
- R A Andersen
- Bigelow Laboratory for Ocean Sciences, West Boothbay Harbor, ME 04575, USA.
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Craig Bailey J, Bidigare RR, Christensen SJ, Andersen RA. Phaeothamniophyceae Classis Nova: A New Lineage of Chromophytes Based upon Photosynthetic Pigments, rbcL Sequence Analysis and Ultrastructure. Protist 1998. [DOI: 10.1016/s1434-4610(98)70032-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Cavalier-Smith T. Sagenista and bigyra, two phyla of heterotrophic heterokont chromists. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0003-9365(97)80006-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Amoeboflagellates and mitochondrial cristae in eukaryote evolution: megasystematics of the new protozoan subkingdoms eozoa and neozoa. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0003-9365(97)80051-6] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Leipe DD, Tong SM, Goggin CL, Slemenda SB, Pieniazek NJ, Sogin ML. 16S-like rDNA sequences from Developayella elegans, Labyrinthuloides haliotidis, and Proteromonas lacertae confirm that the stramenopiles are a primarily heterotrophic group. Eur J Protistol 1996. [DOI: 10.1016/s0932-4739(96)80004-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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