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Fabiano L. Thompson - One of the best experts on this subject based on the ideXlab platform.
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Turbulence-driven shifts in holobionts and planktonic microbial assemblages in St. Peter and St. Paul Archipelago, Mid-Atlantic Ridge, Brazil
Frontiers in microbiology, 2015Co-Authors: Ana Paula B. Moreira, Pedro M. Meirelles, Eidy De O. Santos, Gilberto M. Amado-filho, Ronaldo B. Francini-filho, Cristiane C. Thompson, Fabiano L. ThompsonAbstract:The aim of this study was to investigate the planktonic and the holobiont Madracis decactis (Scleractinia) microbial diversity along a turbulence-driven upwelling event, in the world´s most isolated tropical island, St Peter and St Paul Archipelago (SPSPA, Brazil). Twenty one metagenomes were obtained for seawater (N=12), healthy and bleached holobionts (N=9) before, during and after the episode of high seawater turbulence and upwelling. Microbial assemblages differed between low turbulence-low nutrient (LLR) and high-turbulence-high nutrient (HHR) regimes in seawater. During LLR there was a balance between autotrophy and heterotrophy in the bacterioplankton and the ratio cyanobacteria:heterotrophs ~1 (C:H). Prochlorales, unclassified Alphaproteobacteria and Euryarchaeota were the dominant bacteria and archaea, respectively. Basic metabolisms and cyanobacterial phages characterized the LLR. During HHR C:H
Tadashi Maruyama - One of the best experts on this subject based on the ideXlab platform.
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intracellular symbiosis of a photosynthetic prokaryote prochloron sp in a colonial ascidian
Invertebrate Biology, 1996Co-Authors: Euichi Hirose, Lanna Cheng, Tadashi Maruyama, Ralph A LewinAbstract:Cells of a symbiotic prokaryote, Prochloron sp., in colonies of a tropical ascidian, Lissoclinum punctatum, occur not only outside but also inside cells of the host. Cells of these photosynthetic symbionts of ascidians have previously been reported only extracellularly. The intracellular and extracellular symbionts do not differ morphologically. The host cells carrying the symbionts are freely distributed in the ascidian tunic. They probably endocytize the symbionts and then retain them within a vacuole. Since the intracellular prokaryotes showed no evidence of rejection or degeneration, this association between tunic phagocytes of L. punctatum and cells of Prochloron sp. seems to constitute a stable symrnbiosis, comparable to the postulated ancestral association between heterotrophic cells and the photosynthetic prokaryotes which gave rise to chloroplasts. Additional key words: algae, cyanobacteria, plastid evolution, prochlorophytes, tunicates Chloroplasts are photosynthetic organelles found in all photosynthetic eukaryotes. There is now convincing evidence from molecular biological studies on 16S-rRNA and RNA polymerase subunit (rpo Cl) and ribulose-bisphosphate carboxylase genes (Seewaldt & Stackebrandt 1982; Palenik & Haselkorn 1992; Urbach et al. 1992; Shimada et al. 1995) that these organelles originated from prokaryotic photosynthetic endosymbionts (cyanobacteria) engulfed and retained by heterotrophic host cells (Lewin 1981; Margulis 1981). Symbiotic photosynthetic prokaryotes are therefore of interest in relation to the evolution of chloroplasts. Prochloron is a genus of unicellular prokaryotes with the same chlorophyll pigments, chl a and b, as those in the chloroplasts of green algae and all other green plants (Lewin 1976). Prochlorophyta/Prochlorales was originally established (Lewin 1976, 1977; Florenzano et al. 1986) for prokaryotes that bear chl. a and b, lack bilin pigments, and generate oxygen in photosynthesis; molecular phylogenetic studies, however, indicate that this is a polyphyletic group whose members arose within the cyanobacterial radiation and should be treated as members of Cyanophyta/Cyanobacteria (Palenik & Haselkorn 1992; Urbach et al. 1992; Shimada et al. 1995). Cells of Prochloron occur in coral reef areas, almost exclusively as symbionts of colonial didemnid ascidians (Lewin & Cheng 1989). There the symbionts are normally associated with external or internal colony surfaces, but outside the host cells. Prochloron didemni LEWIN 1977 was originally described from the outer surfaces of didemnid colonies; but since no prochloron cells have been cultured in vitro, and specific distinctions remain to be established, we will refer to the symbionts in this paper simply as Prochloron sp. We present here the first report of Prochloron sp. as an intracellular symbiont in a didemnid ascidian, Lissoclinum punctatum KOTT 1977. Recent molecular biological data (Palenik & Haselkorn 1992; Urbach et al. 1992) indicate that the phylogenetic affinities of chloroplasts are closer to other cyanobacteria than to Prochloron, but we suggest that intracellular Prochloron can be regarded as a model of the ancestral green plastid.
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partial sequence of ribulose 1 5 bisphosphate carboxylase oxygenase and the phylogeny of prochloron and prochlorococcus Prochlorales
Journal of Molecular Evolution, 1995Co-Authors: Atsuhiro Shimada, Satoru Kanai, Tadashi MaruyamaAbstract:The prochlorophytes, oxygenic photosynthetic prokaryotes having no phycobiliprotein but possessing chlorophylls a and b, have been proposed to have a common ancestry with green chloroplasts, yet this is still controversal. We report here that partial sequence comparisons of the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase, including sequence data from two prochlorophytes, Prochlorococcus and Prochloron, indicate that Prochlorococcus is more closely related to a photosynthetic bacterium, Chromatium vinosum (γ-purple bacteria), than to cyanobacteria, while Prochloron is closely related to the prochlorophyte Prochlorothrix and to cyanobacteria. The molecular phylogenetic tree indicates that a common ancestor of Prochlorococcus and γ-purple bacteria branched off from the land plant lineage earlier than Prochloron, Prochlorothrix, and cyanobacteria.
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Partial sequence of ribulose-1,5-bisphosphate carboxylase/oxygenase and the phylogeny of Prochloron and Prochlorococcus (Prochlorales)
Journal of Molecular Evolution, 1995Co-Authors: Atsuhiro Shimada, Satoru Kanai, Tadashi MaruyamaAbstract:The prochlorophytes, oxygenic photosynthetic prokaryotes having no phycobiliprotein but possessing chlorophylls a and b, have been proposed to have a common ancestry with green chloroplasts, yet this is still controversal. We report here that partial sequence comparisons of the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase, including sequence data from two prochlorophytes, Prochlorococcus and Prochloron, indicate that Prochlorococcus is more closely related to a photosynthetic bacterium, Chromatium vinosum (γ-purple bacteria), than to cyanobacteria, while Prochloron is closely related to the prochlorophyte Prochlorothrix and to cyanobacteria. The molecular phylogenetic tree indicates that a common ancestor of Prochlorococcus and γ-purple bacteria branched off from the land plant lineage earlier than Prochloron, Prochlorothrix, and cyanobacteria.
Ana Paula B. Moreira - One of the best experts on this subject based on the ideXlab platform.
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Turbulence-driven shifts in holobionts and planktonic microbial assemblages in St. Peter and St. Paul Archipelago, Mid-Atlantic Ridge, Brazil
Frontiers in microbiology, 2015Co-Authors: Ana Paula B. Moreira, Pedro M. Meirelles, Eidy De O. Santos, Gilberto M. Amado-filho, Ronaldo B. Francini-filho, Cristiane C. Thompson, Fabiano L. ThompsonAbstract:The aim of this study was to investigate the planktonic and the holobiont Madracis decactis (Scleractinia) microbial diversity along a turbulence-driven upwelling event, in the world´s most isolated tropical island, St Peter and St Paul Archipelago (SPSPA, Brazil). Twenty one metagenomes were obtained for seawater (N=12), healthy and bleached holobionts (N=9) before, during and after the episode of high seawater turbulence and upwelling. Microbial assemblages differed between low turbulence-low nutrient (LLR) and high-turbulence-high nutrient (HHR) regimes in seawater. During LLR there was a balance between autotrophy and heterotrophy in the bacterioplankton and the ratio cyanobacteria:heterotrophs ~1 (C:H). Prochlorales, unclassified Alphaproteobacteria and Euryarchaeota were the dominant bacteria and archaea, respectively. Basic metabolisms and cyanobacterial phages characterized the LLR. During HHR C:H
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Turbulence-driven shifts in holobionts and planktonic microbial assemblages in St Peter & St Paul Archipelago, Mid-Atlantic Ridge, Brazil
Frontiers Media S.A., 2015Co-Authors: Ana Paula B. Moreira, Pedro M. Meirelles, Gilberto M. Amado-filho, Ronaldo B. Francini-filho, Cristiane C. Thompson, Eidy O. Santos, Fabiano EthompsonAbstract:The aim of this study was to investigate the planktonic and the holobiont Madracis decactis (Scleractinia) microbial diversity along a turbulence-driven upwelling event, in the world´s most isolated tropical island, St Peter and St Paul Archipelago (SPSPA, Brazil). Twenty one metagenomes were obtained for seawater (N=12), healthy and bleached holobionts (N=9) before, during and after the episode of high seawater turbulence and upwelling. Microbial assemblages differed between low turbulence-low nutrient (LLR) and high-turbulence-high nutrient (HHR) regimes in seawater. During LLR there was a balance between autotrophy and heterotrophy in the bacterioplankton and the ratio cyanobacteria:heterotrophs ~1 (C:H). Prochlorales, unclassified Alphaproteobacteria and Euryarchaeota were the dominant bacteria and archaea, respectively. Basic metabolisms and cyanobacterial phages characterized the LLR. During HHR C:H
Natalia Velichko - One of the best experts on this subject based on the ideXlab platform.
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Another view on the role of photosynthetic pigments in taxonomy of oxygenic-phototrophic bacteria : Proposed rejection of the order Prochlorales Florenzano, Balloni, and Materassi 1986 (emend. Burger-Wiersma, Stal, and Mur 1989), the family Prochlora
International Journal of Systematic and Evolutionary Microbiology, 1997Co-Authors: A. V. Pinevich, Svetlana G. Averina, Natalia VelichkoAbstract:We propose that the order Prochlorales Florenzano, Balloni, and Materassi 1986 (emend. Burger-Wiersma, Stal, and Mur 1989), the family Prochloraceae Florenzano, Balloni, and Materassi 1986, and the family Prochlorotrichaceae Burger-Wiersma, Stal, and Mur 1989, validly published in the International Journal of Systematic Bacteriology under the rules of the Bacteriological Code, be rejected because of the imperfection of ordinal diagnosis. The oxygenic-phototrophic prokaryotes involved are proposed to be incorporated under their validly published names into the orders Chroococcales and Oscillatoriales of the “Cyanobacteria” group. Correspondingly, the latter is proposed to be upgraded to equal “Oxygenic photosynthetic bacteria” (Section 19 in Bergey's Manual).
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New ultrastructural aspects of membranes and cell inclusions in Prochlorothrix hollandica (Prochlorales, Cyanobacteria).
Microbios, 1996Co-Authors: A. V. Pinevich, Svetlana G. Averina, H. C. P. Matthijs, Olga V. Gavrilova, Natalia VelichkoAbstract:An electron microscopic study of Prochlorothrix hollandica revealed new aspects of the prochlorophytan ultrastructure. These were concerned with (1) starch-type cell inclusions; (2) the association of thylakoids with carboxysomes; (3) Bayer-type junctions between the cytoplasmic membrane and outer membrane; and (4) interactions, in particular, of the thylakoid centre-type between the cytoplasmic membrane and thylakoids. The functional implications of this morphology, as well as the ultrastructural similarities and dissimilarities of prochlorophytes with cyanobacteria, in general, are discussed.
Cristiane C. Thompson - One of the best experts on this subject based on the ideXlab platform.
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Turbulence-driven shifts in holobionts and planktonic microbial assemblages in St. Peter and St. Paul Archipelago, Mid-Atlantic Ridge, Brazil
Frontiers in microbiology, 2015Co-Authors: Ana Paula B. Moreira, Pedro M. Meirelles, Eidy De O. Santos, Gilberto M. Amado-filho, Ronaldo B. Francini-filho, Cristiane C. Thompson, Fabiano L. ThompsonAbstract:The aim of this study was to investigate the planktonic and the holobiont Madracis decactis (Scleractinia) microbial diversity along a turbulence-driven upwelling event, in the world´s most isolated tropical island, St Peter and St Paul Archipelago (SPSPA, Brazil). Twenty one metagenomes were obtained for seawater (N=12), healthy and bleached holobionts (N=9) before, during and after the episode of high seawater turbulence and upwelling. Microbial assemblages differed between low turbulence-low nutrient (LLR) and high-turbulence-high nutrient (HHR) regimes in seawater. During LLR there was a balance between autotrophy and heterotrophy in the bacterioplankton and the ratio cyanobacteria:heterotrophs ~1 (C:H). Prochlorales, unclassified Alphaproteobacteria and Euryarchaeota were the dominant bacteria and archaea, respectively. Basic metabolisms and cyanobacterial phages characterized the LLR. During HHR C:H
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Turbulence-driven shifts in holobionts and planktonic microbial assemblages in St Peter & St Paul Archipelago, Mid-Atlantic Ridge, Brazil
Frontiers Media S.A., 2015Co-Authors: Ana Paula B. Moreira, Pedro M. Meirelles, Gilberto M. Amado-filho, Ronaldo B. Francini-filho, Cristiane C. Thompson, Eidy O. Santos, Fabiano EthompsonAbstract:The aim of this study was to investigate the planktonic and the holobiont Madracis decactis (Scleractinia) microbial diversity along a turbulence-driven upwelling event, in the world´s most isolated tropical island, St Peter and St Paul Archipelago (SPSPA, Brazil). Twenty one metagenomes were obtained for seawater (N=12), healthy and bleached holobionts (N=9) before, during and after the episode of high seawater turbulence and upwelling. Microbial assemblages differed between low turbulence-low nutrient (LLR) and high-turbulence-high nutrient (HHR) regimes in seawater. During LLR there was a balance between autotrophy and heterotrophy in the bacterioplankton and the ratio cyanobacteria:heterotrophs ~1 (C:H). Prochlorales, unclassified Alphaproteobacteria and Euryarchaeota were the dominant bacteria and archaea, respectively. Basic metabolisms and cyanobacterial phages characterized the LLR. During HHR C:H