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George S Bullerjahn - One of the best experts on this subject based on the ideXlab platform.
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doi: 10.3389/fmicb.2012.00173 Cyanobacteria of the genus Prochlorothrix†
2012Co-Authors: Er Pinevich, George S Bullerjahn, Natalia Ivanikova, Alexander Pinevich MicrobiologyAbstract:Green cyanobacteria differ from the blue–green cyanobacteria by the possession of a chlorophyll-containing light-harvesting antenna. Three genera of the green cyanobacteria namely Acaryochloris, Prochlorococcus, and Prochloron are unicellular and inhabit marine environments. Prochlorococcus marinus attracts most attention due to its prominent role in marine primary productivity. The fourth genus Prochlorothrix is represented by the fila-mentous freshwater strains. Unlike the other green cyanobacteria, Prochlorothrix strains are remarkably rare: to date, living isolates have been limited to two European locations. Taking into account fluctuating blooms, morphological resemblance to Planktothrix and Pseudanabaena, and unsuccessful attempts to obtain enrichments of Prochlorothrix, the most successful strategy to search for this cyanobacterium involves PCR with environ-mental DNA and Prochlorothrix-specific primers. This approach has revealed a broader distribution of Prochlorothrix. Marker genes have been found in at least two additional locations. Despite of the growing evidence for naturally occurring Prochlorothrix, there are only a few cultured strains with one of them (PCC 9006) being claimed to be axenic. In multixenic cultures, Prochlorothrix is accompanied by heterotrophic bacteria indicating
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dynamics in the transient complex of plastocyanin cytochrome f from Prochlorothrix hollandica
Journal of the American Chemical Society, 2008Co-Authors: Rinske Hulsker, George S Bullerjahn, Maria V Baranova, Marcellus UbbinkAbstract:The nature of transient protein complexes can range from a highly dynamic ensemble of orientations to a single well-defined state. This represents variation in the equilibrium between the encounter and final, functional state. The transient complex between plastocyanin (Pc) and cytochrome f (cytf) of the cyanobacterium Prochlorothrix hollandica was characterized by NMR spectroscopy. Intermolecular pseudocontact shifts and chemical shift perturbations were used as restraints in docking calculations to determine the structure of the wild-type Pc−cytf complex. The orientation of Pc is similar to orientations found in Pc−cytf complexes from other sources. Electrostatics seems to play a modest role in complex formation. A large variability in the ensemble of lowest energy structures indicates a dynamic nature of the complex. Two unusual hydrophobic patch residues in Pc have been mutated to the residues found in other plastocyanins (Y12G/P14L). The binding constants are similar for the complexes of cytf with wi...
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dynamics in the transient complex of plastocyanin cytochrome f from Prochlorothrix hollandica
Journal of the American Chemical Society, 2008Co-Authors: Rinske Hulsker, George S Bullerjahn, Maria V Baranova, Marcellus UbbinkAbstract:The nature of transient protein complexes can range from a highly dynamic ensemble of orientations to a single well-defined state. This represents variation in the equilibrium between the encounter and final, functional state. The transient complex between plastocyanin (Pc) and cytochrome f (cytf) of the cyanobacterium Prochlorothrix hollandica was characterized by NMR spectroscopy. Intermolecular pseudocontact shifts and chemical shift perturbations were used as restraints in docking calculations to determine the structure of the wild-type Pc−cytf complex. The orientation of Pc is similar to orientations found in Pc−cytf complexes from other sources. Electrostatics seems to play a modest role in complex formation. A large variability in the ensemble of lowest energy structures indicates a dynamic nature of the complex. Two unusual hydrophobic patch residues in Pc have been mutated to the residues found in other plastocyanins (Y12G/P14L). The binding constants are similar for the complexes of cytf with wi...
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mutagenesis of Prochlorothrix plastocyanin reveals additional features in photosystem i interactions
Journal of Biological Chemistry, 2003Co-Authors: Manuel Hervas, Eugene Myshkin, George S Bullerjahn, Nadejda Vintonenko, Miguel A. De La Rosa, José A. NavarroAbstract:Three surface residues of plastocyanin from Prochlorothrix hollandica have been modified by site-directed mutagenesis. Changes have been made in methionine 33, located in the hydrophobic patch of the copper protein, and in arginine 86 and proline 53, both located in the eastern hydrophilic area. The reactivity toward photosystem I of single mutants M33N, P53A, P53E, R86Q, R86E, and the double mutant M33N/P14L has been studied by laser flash absorption spectroscopy. All the mutations yield increased reactivity of plastocyanin toward photosystem I as compared with wild type plastocyanin, thus indicating that in Prochlorothrix electron donation to photosystem I is not optimized. The most drastic increases in the intracomplex electron transfer rate are obtained with mutants in methionine 33, whereas replacing arginine 86 only modestly affects the plastocyanin-photosystem I equilibrium constant for complex formation. Mutations at position 53 also promote major changes in the association of plastocyanin with photosystem I, yielding a change from a mechanism involving complex formation to a simpler collisional interaction. Molecular dynamics calculations indicate that mutations at position 33 promote changes in the H-bond network around the copper center. The comparative kinetic analysis of the reactivity of Prochlorothrix plastocyanin mutants toward photosystem I from other cyanobacteria reveals that mutations M33N, P53A, and P53E result in enhanced general reactivity.
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Plastocyanin-cytochrome f interactions: the influence of hydrophobic patch mutations studied by NMR spectroscopy.
Biochemistry, 2002Co-Authors: Peter B Crowley, George S Bullerjahn, Nadejda Vintonenko, Marcellus UbbinkAbstract:Transient complex formation between plastocyanin from Prochlorothrix hollandica and cytochrome f from Phormidium laminosumwas investigated using nuclear magnetic resonance (NMR) spectroscopy. Binding curves derived from NMR titrations at 10 mM ionic strength reveal a 1:1 stoichiometry and a binding constant of 6 ((2) 10 3 M -1 for complex formation, 1 order of magnitude larger than that for the physiological plastocyanin-cytochrome f complex from Ph. laminosum. Chemical- shift perturbation mapping indicates that the hydrophobic patch of plastocyanin is involved in the complex interface. When the unusual hydrophobic patch residues of P. hollandica plastocyanin were reverted to the conserved residues found in most other plastocyanins (Y12G/P14L), the binding constant for the interaction with cytochrome f was unaffected. However, the chemical shift perturbation map was considerably different, and the size of the average perturbation decreased by 40%. The complexes of both the wild-type and double mutant plastocyanin with cytochrome f were sensitive to ionic strength, contrary to the physiological complex. The possible implications of these findings for the mechanism of transient complex formation are discussed.
A. V. Pinevich - One of the best experts on this subject based on the ideXlab platform.
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draft genome of Prochlorothrix hollandica ccap 1490 1t calu1027 the chlorophyll a b containing filamentous cyanobacterium
Standards in Genomic Sciences, 2016Co-Authors: Natalia Velichko, Mikhail Rayko, Ekaterina Chernyaeva, Alla Lapidus, A. V. PinevichAbstract:Prochlorothrix hollandica is filamentous non-heterocystous cyanobacterium which possesses the chlorophyll a/b light-harvesting complexes. Despite the growing interest in unusual green-pigmented cyanobacteria (prochlorophytes) to date only a few sequenced genome from prochlorophytes genera have been reported. This study sequenced the genome of Prochlorothrix hollandica CCAP 1490/1T (CALU1027). The produced draft genome assembly (5.5 Mb) contains 3737 protein-coding genes and 114 RNA genes.
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consortium of the bichlorophyllous cyanobacterium Prochlorothrix hollandica and chemoheterotrophic partner bacteria culture and metagenome based description
Environmental Microbiology Reports, 2015Co-Authors: Natalia Velichko, Ekaterina Chernyaeva, Svetlana G. Averina, Alla Lapidus, Olga V. Gavrilova, A. V. PinevichAbstract:Summary 'Bacterial consortium' sensu lato applies to mutualism or syntrophy-based systems consisting of unrelated bacteria. Consortia of cyanobacteria have been preferentially studied on Anabaena epibioses; non-photosynthetic satellites of other filamentous or unicellular cyanobacteria were also considered although structure-functional data are few. At the same time, information about consortia of cyanobacteria which have light-harvesting antennae distinct from standard phycobilisome was missing. In this study, we characterized first, via a polyphasic approach, the cultivable consortium of Prochlorothrix hollandica CCAP 1490/1 (filamentous cyanobacterium which contains chlorophylls a, b/carotenoid/protein complex in the absence of phycobilisome) and non- photosynthetic heterotrophic bacteria. The strains of most abundant satellites were isolated and identified. Consortium metagenome reconstructed via 454-pyro and Illumina sequencing was shown to include, except for P. hollandica, several phylotypes of Proteobacteria and Bacteroidetes. The ratio of con- sortium members was essentially stable irrespective of culture age, and restored after artificially imposed imbalance. The consortium had a complex spatial arrangement as demonstrated by FISH and SEM images of the association, epibiosis, and biofilm type. Preliminary data of metagenome annotation agreed with the hypothesis that satellite bacteria contribute to P. hollandica protection from reactive oxygen species (ROS).
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Consortium of the ‘bichlorophyllous’ cyanobacterium Prochlorothrix hollandica and chemoheterotrophic partner bacteria: culture and metagenome‐based description
Environmental microbiology reports, 2015Co-Authors: Natalia Velichko, Ekaterina Chernyaeva, Svetlana G. Averina, Alla Lapidus, Olga V. Gavrilova, A. V. PinevichAbstract:Summary 'Bacterial consortium' sensu lato applies to mutualism or syntrophy-based systems consisting of unrelated bacteria. Consortia of cyanobacteria have been preferentially studied on Anabaena epibioses; non-photosynthetic satellites of other filamentous or unicellular cyanobacteria were also considered although structure-functional data are few. At the same time, information about consortia of cyanobacteria which have light-harvesting antennae distinct from standard phycobilisome was missing. In this study, we characterized first, via a polyphasic approach, the cultivable consortium of Prochlorothrix hollandica CCAP 1490/1 (filamentous cyanobacterium which contains chlorophylls a, b/carotenoid/protein complex in the absence of phycobilisome) and non- photosynthetic heterotrophic bacteria. The strains of most abundant satellites were isolated and identified. Consortium metagenome reconstructed via 454-pyro and Illumina sequencing was shown to include, except for P. hollandica, several phylotypes of Proteobacteria and Bacteroidetes. The ratio of con- sortium members was essentially stable irrespective of culture age, and restored after artificially imposed imbalance. The consortium had a complex spatial arrangement as demonstrated by FISH and SEM images of the association, epibiosis, and biofilm type. Preliminary data of metagenome annotation agreed with the hypothesis that satellite bacteria contribute to P. hollandica protection from reactive oxygen species (ROS).
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Probing environmental DNA reveals circum-Baltic presence and diversity of chlorophyll a/b-containing filamentous cyanobacteria (genus Prochlorothrix)
Hydrobiologia, 2014Co-Authors: Nataliya Vladislavovna Velichko, Svetlana G. Averina, Olga V. Gavrilova, Natalia Ivanikova, A. V. PinevichAbstract:Cyanobacteria that possess phycobilisomes, light-harvesting antenna, have been well studied. In contrast, more rare green cyanobacteria (four genera/five species) that instead make use of chlorophyll–protein complex are poorly studied. In particular, the genus Prochlorothrix is represented by a small environmental DNA database and reports of only two cultured species from Northern Europe. In this work, marine and freshwater habitats of Northwestern Russia were investigated. PCR with Prochlorothrix 16S rRNA gene specific primers, FISH analysis with a Prochlorothrix 16S rRNA-targeted probe, Prochlorothrix culture isolation, and phylogenetic analysis of Prochlorothrix diversity were carried out. We identified Prochlorothrix 16S rDNA in samples from the St. Petersburg region and corroborated this finding by FISH. Attempts to isolate PCR- and FISH-detected Prochlorothrix strains were unsuccessful. Phylogenetic analysis revealed that the Prochlorothrix 16S rDNA sequences identified were very similar and formed a single cluster with high bootstrap support. Some of these sequences represent environmental strains of the species Prochlorothrix hollandica and P. scandica, while the others belong to new Prochlorothrix species or even to a new Prochlorothrix-related genus. Our results suggest a broader distribution and greater diversity in Prochlorothrix than previously thought.
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Polyphasic emended description of the filamentous prochlorophyte Prochlorothrix scandica Skulberg 2008
Algological Studies, 2013Co-Authors: Nataliya Vladislavovna Velichko, Svetlana G. Averina, Olga V. Gavrilova, Natalia Ivanikova, Anna S. Timofeyeva, A. V. PinevichAbstract:Abstract: Chlorophyll b -containing, phycobiliprotein-less cyanobacterium (“prochlorophyte”) Prochlorothrix scandica Skulberg 2008 represents the second species of the genus Prochlo-rothrix . Distinction between the strains P. scandica NIVA-8/90 and Prochlorothrix hollandica PCC 9006 (CCAP 1490/1 T ) is based predominantly on genomic DNA properties. The degree of DNA reassociation of the two strains is 5 %. Compared to P. hollandica, P. scandica possesses an additional rrn operon. In addition, there is a distinct polymorphism of the highly iterated short palindromes (Hip1). Among the pheno-typic features different in the two species are cell morphology, growth temperature optimum and fatty acids content. Keywords: polyphasic taxonomy, prochlorophytes, cyanobacteria, ITS, Hip1, Prochlorothrix, Prochlorothrix scandica The GenBank accession number for the single 16S−23S ITS sequence of Prochlo-rothrix hollandica PCC 9006 T is HQ316172 and the accession numbers for the two 16S−23S ITS sequences of
Natalia Velichko - One of the best experts on this subject based on the ideXlab platform.
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Draft genome of Prochlorothrix hollandica CCAP 1490/1^T (CALU1027), the chlorophyll a/b-containing filamentous cyanobacterium
Standards in Genomic Sciences, 2016Co-Authors: Natalia Velichko, Mikhail Rayko, Ekaterina Chernyaeva, Alla Lapidus, Alexander PinevichAbstract:Prochlorothrix hollandica is filamentous non-heterocystous cyanobacterium which possesses the chlorophyll a / b light-harvesting complexes. Despite the growing interest in unusual green-pigmented cyanobacteria (prochlorophytes) to date only a few sequenced genome from prochlorophytes genera have been reported. This study sequenced the genome of Prochlorothrix hollandica CCAP 1490/1^T (CALU1027). The produced draft genome assembly (5.5 Mb) contains 3737 protein-coding genes and 114 RNA genes.
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draft genome of Prochlorothrix hollandica ccap 1490 1t calu1027 the chlorophyll a b containing filamentous cyanobacterium
Standards in Genomic Sciences, 2016Co-Authors: Natalia Velichko, Mikhail Rayko, Ekaterina Chernyaeva, Alla Lapidus, A. V. PinevichAbstract:Prochlorothrix hollandica is filamentous non-heterocystous cyanobacterium which possesses the chlorophyll a/b light-harvesting complexes. Despite the growing interest in unusual green-pigmented cyanobacteria (prochlorophytes) to date only a few sequenced genome from prochlorophytes genera have been reported. This study sequenced the genome of Prochlorothrix hollandica CCAP 1490/1T (CALU1027). The produced draft genome assembly (5.5 Mb) contains 3737 protein-coding genes and 114 RNA genes.
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consortium of the bichlorophyllous cyanobacterium Prochlorothrix hollandica and chemoheterotrophic partner bacteria culture and metagenome based description
Environmental Microbiology Reports, 2015Co-Authors: Natalia Velichko, Ekaterina Chernyaeva, Svetlana G. Averina, Alla Lapidus, Olga V. Gavrilova, A. V. PinevichAbstract:Summary 'Bacterial consortium' sensu lato applies to mutualism or syntrophy-based systems consisting of unrelated bacteria. Consortia of cyanobacteria have been preferentially studied on Anabaena epibioses; non-photosynthetic satellites of other filamentous or unicellular cyanobacteria were also considered although structure-functional data are few. At the same time, information about consortia of cyanobacteria which have light-harvesting antennae distinct from standard phycobilisome was missing. In this study, we characterized first, via a polyphasic approach, the cultivable consortium of Prochlorothrix hollandica CCAP 1490/1 (filamentous cyanobacterium which contains chlorophylls a, b/carotenoid/protein complex in the absence of phycobilisome) and non- photosynthetic heterotrophic bacteria. The strains of most abundant satellites were isolated and identified. Consortium metagenome reconstructed via 454-pyro and Illumina sequencing was shown to include, except for P. hollandica, several phylotypes of Proteobacteria and Bacteroidetes. The ratio of con- sortium members was essentially stable irrespective of culture age, and restored after artificially imposed imbalance. The consortium had a complex spatial arrangement as demonstrated by FISH and SEM images of the association, epibiosis, and biofilm type. Preliminary data of metagenome annotation agreed with the hypothesis that satellite bacteria contribute to P. hollandica protection from reactive oxygen species (ROS).
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Consortium of the ‘bichlorophyllous’ cyanobacterium Prochlorothrix hollandica and chemoheterotrophic partner bacteria: culture and metagenome‐based description
Environmental microbiology reports, 2015Co-Authors: Natalia Velichko, Ekaterina Chernyaeva, Svetlana G. Averina, Alla Lapidus, Olga V. Gavrilova, A. V. PinevichAbstract:Summary 'Bacterial consortium' sensu lato applies to mutualism or syntrophy-based systems consisting of unrelated bacteria. Consortia of cyanobacteria have been preferentially studied on Anabaena epibioses; non-photosynthetic satellites of other filamentous or unicellular cyanobacteria were also considered although structure-functional data are few. At the same time, information about consortia of cyanobacteria which have light-harvesting antennae distinct from standard phycobilisome was missing. In this study, we characterized first, via a polyphasic approach, the cultivable consortium of Prochlorothrix hollandica CCAP 1490/1 (filamentous cyanobacterium which contains chlorophylls a, b/carotenoid/protein complex in the absence of phycobilisome) and non- photosynthetic heterotrophic bacteria. The strains of most abundant satellites were isolated and identified. Consortium metagenome reconstructed via 454-pyro and Illumina sequencing was shown to include, except for P. hollandica, several phylotypes of Proteobacteria and Bacteroidetes. The ratio of con- sortium members was essentially stable irrespective of culture age, and restored after artificially imposed imbalance. The consortium had a complex spatial arrangement as demonstrated by FISH and SEM images of the association, epibiosis, and biofilm type. Preliminary data of metagenome annotation agreed with the hypothesis that satellite bacteria contribute to P. hollandica protection from reactive oxygen species (ROS).
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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.
Susan S. Golden - One of the best experts on this subject based on the ideXlab platform.
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Conserved relationship between psbH and petBD genes: presence of a shared upstream element in Prochlorothrix hollandica
Plant Molecular Biology, 1992Co-Authors: Karen L. Greer, Susan S. GoldenAbstract:Prochlorophytes are an unusual group of prokaryotic oxygenic photoautotrophs that morphologically appear to bridge the gap between cyanobacteria and the chloroplasts of eukaryotic plants. Molecular data place this group evolutionarily within the cyanobacteria, but they have a photosynthetic apparatus that is very similar to that found in chloroplasts. We have sequenced from the prochlorophyte Prochlorothrix hollandica a set of genes ( psbB, psbH, petB and petD ) that has a conserved organization in chloroplast genomes that is different from the organization in cyanobacterial genomes. The four genes are linked as an operon in chloroplasts, but only petB and petD are closely linked and cotranscribed in cyanobacteria. Although the prochlorophyte gene arrangement resembles that of cyanobacteria, one feature suggests the coordinated regulation of the unlinked genes. A 93 bp region of absolute conservation occurs upstream of the psbH gene and the petBD operon, near the site of transcription initiation in each gene set. This conserved element may indicate an alternative to cotranscription for achieving co-regulation of the psbH and petBD genes in the prochlorophyte.
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Comparison of Sequences and Organization of Photosynthesis Genes among the Prochlorophyte Prochlorothrix Hollandica, Cyanobacteria, and Chloroplasts
Origins of Plastids, 1992Co-Authors: Susan S. Golden, Clifford W. Morden, Karen L. GreerAbstract:Prochlorophytes similar to Prochloron sp. and Prochlorothrix hollandica have been suggested as possible progenitors of the plastids of green algae and land plants because they are oxygenic photosynthetic prokaryotes that possess chlorophyll b. We have sequenced the P. hollandica genes encoding the photosystem II (PSII) reaction-center protein Dl (psbA) and the large and small subunits of Rubisco (rbcL and rbcS) for comparison with those of other taxa to assess the phylogenetic placement of this species. P. hollandica has two psbA genes that encode identical D1 proteins. The gene sequences predict a seven-amino-acid deletion at the carboxy terminus of the deduced D1 protein relative to all cyanobacterial sequences examined, a feature that previously had been observed only in plant psbA sequences. Phylogenetic analysis of deduced D1 protein sequences indicated that the phylogenetic position of P. hollandica is either intermediate between cyanobacteria and chloroplasts or on a branch associated with Synechococcus sp. strain Pasteur Culture Collection (PCC) 7942 (one of the strains hitherto known as Anacystis nidulans) adjacent to the chloroplast lineage. The P. hollandica rbcL and rbcS genes are arranged in an operon, as is the case in cyanobacterial and other photosynthetic bacterial genomes and in the cyanelle genome of the eukaryote Cyanophora paradoxa. Phylogenetic analysis using deduced amino-acid sequences of rbcL and rbcS indicated that P. hollandica is more closely related to cyanobacteria than to the green plastid lineage. We also examined a group of genes that are arranged differently in the genomes of chloroplasts and cyanobacteria. The psbB, psbH, petB, and petD genes, encoding components of PSII and the cytochrome b 6 /f complex, are arranged as an operon in chloroplast genomes. In cyanobacterial genomes, petB and petD form an operon, but psbB and psbH are not part of this cluster. In P. hollandica these genes are arranged as in cyanobacteria, with psbB and psbH not closely linked to each other or to the petBD operon. However, psbH and petBD are preceded by identical 93-bp elements near transcription start sites for each cistron, suggesting that the clustering of these genes in chloroplasts and the presence of putative regulatory elements in the prochlorophyte may represent two mechanisms for coordinating their expression. These studies of gene sequences and gene arrangement support previous analyses of 16S rRNA sequences which indicated that P. hollandica is a close relative of the cyanobacteria, and reveal few special similarities at the gene level among prochlorophytes and chloroplasts.
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Sequence analysis and phylogenetic reconstruction of the genes encoding the large and small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase from the chlorophyllb-containing prokaryoteProchlorothrix hollandica
Journal of Molecular Evolution, 1991Co-Authors: Clifford W. Morden, Susan S. GoldenAbstract:Prochlorophytes similar to Prochloron sp. and Prochlorothrix hollandica have been suggested as possible progenitors of the plastids of green algae and land plants because they are prokaryotic organisms that possess chlorophyll b (chl b ). We have sequenced the Prochlorothrix genes encoding the large and small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco), rbcL and rbcS , for comparison with those of other taxa to assess the phylogenetic relationship of this species. Length differences in the large subunit polypeptide among all sequences compared occur primarily at the amino terminus, where numerous short gaps are present, and at the carboxy terminus, where sequences of Alcaligenes eutrophus and non-chlorophyll b algae are several amino acids longer. Some domains in the small subunit polypeptide are conserved among all sequences analyzed, yet in other domains the sequences of different phylogenetic groups exhibit specific structural characteristics. Phylogenetic analyses of rbcL and rbcS using Wagner parsimony analysis of deduced amino acid sequences indicate that Prochlorothrix is more closely related to cyanobacteria than to the green plastid lineage. The molecular phylogenies suggest that plastids originated by at least three separate primary endosymbiotic events, i.e., once each leading to green algae and land plants, to red algae, and to Cyanophora paradoxa . The Prochlorothrix rubisco genes show a strong GC bias, with 68% of the third codon positions being G or C. Factors that may affect the GC content of different genomes are discussed.
Tadashi Maruyama - One of the best experts on this subject based on the ideXlab platform.
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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.