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  1 / 24 MEDLINE  
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[PMID]:25990300
[Au] Autor:Velichko N; Chernyaeva E; Averina S; Gavrilova O; Lapidus A; Pinevich A
[Ad] Endereço:Department of Microbiology, Faculty of Biology, St Petersburg State University, St Petersburg, Russia.
[Ti] Título:Consortium of the 'bichlorophyllous' cyanobacterium Prochlorothrix hollandica and chemoheterotrophic partner bacteria: culture and metagenome-based description.
[So] Source:Environ Microbiol Rep;7(4):623-33, 2015 Aug.
[Is] ISSN:1758-2229
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:'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 consortium 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).
[Mh] Termos MeSH primário: Bacteroidetes/classificação
Biota
Metagenoma
Consórcios Microbianos
Prochlorothrix/crescimento & desenvolvimento
Proteobactérias/classificação
[Mh] Termos MeSH secundário: Bacteroidetes/genética
Bacteroidetes/crescimento & desenvolvimento
Bacteroidetes/isolamento & purificação
Análise por Conglomerados
Hibridização in Situ Fluorescente
Microscopia Eletrônica de Varredura
Dados de Sequência Molecular
Filogenia
Prochlorothrix/genética
Proteobactérias/genética
Proteobactérias/crescimento & desenvolvimento
Proteobactérias/isolamento & purificação
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1604
[Cu] Atualização por classe:150722
[Lr] Data última revisão:
150722
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150521
[St] Status:MEDLINE
[do] DOI:10.1111/1758-2229.12298


  2 / 24 MEDLINE  
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[PMID]:22728755
[Au] Autor:Hamada F; Yokono M; Hirose E; Murakami A; Akimoto S
[Ad] Endereço:Graduate School of Science, Kobe University, Kobe 657-8501, Japan.
[Ti] Título:Excitation energy relaxation in a symbiotic cyanobacterium, Prochloron didemni, occurring in coral-reef ascidians, and in a free-living cyanobacterium, Prochlorothrix hollandica.
[So] Source:Biochim Biophys Acta;1817(11):1992-7, 2012 Nov.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The marine cyanobacterium Prochloron is a unique photosynthetic organism that lives in obligate symbiosis with colonial ascidians. We compared Prochloron harbored in four different host species and cultured Prochlorothrix by means of spectroscopic measurements, including time-resolved fluorescence, to investigate host-induced differences in light-harvesting strategies between the cyanobacteria. The light-harvesting efficiency of photosystems including antenna Pcb, PS II-PS I connection, and pigment status, especially that of PS I Red Chls, were different among the four samples. We also discuss relationships between these observed characteristics and the light conditions, to which Prochloron cells are exposed, influenced by distribution pattern in the host colonies, presence or absence of tunic spicules, and microenvironments within the ascidians' habitat.
[Mh] Termos MeSH primário: Prochloron/metabolismo
Prochlorothrix/metabolismo
Simbiose
Urocordados/microbiologia
[Mh] Termos MeSH secundário: Animais
Complexo de Proteína do Fotossistema I/fisiologia
Complexo de Proteína do Fotossistema II/fisiologia
Espectrometria de Fluorescência
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Photosystem I Protein Complex); 0 (Photosystem II Protein Complex)
[Em] Mês de entrada:1211
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120626
[St] Status:MEDLINE
[do] DOI:10.1016/j.bbabio.2012.06.008


  3 / 24 MEDLINE  
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[PMID]:22302713
[Au] Autor:Tsuchiya T; Mizoguchi T; Akimoto S; Tomo T; Tamiaki H; Mimuro M
[Ad] Endereço:Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501 Japan.
[Ti] Título:Metabolic engineering of the Chl d-dominated cyanobacterium Acaryochloris marina: production of a novel Chl species by the introduction of the chlorophyllide a oxygenase gene.
[So] Source:Plant Cell Physiol;53(3):518-27, 2012 Mar.
[Is] ISSN:1471-9053
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:In oxygenic photosynthetic organisms, the properties of photosynthetic reaction systems primarily depend on the Chl species used. Acquisition of new Chl species with unique optical properties may have enabled photosynthetic organisms to adapt to various light environments. The artificial production of a new Chl species in an existing photosynthetic organism by metabolic engineering provides a model system to investigate how an organism responds to a newly acquired pigment. In the current study, we established a transformation system for a Chl d-dominated cyanobacterium, Acaryochloris marina, for the first time. The expression vector (constructed from a broad-host-range plasmid) was introduced into A. marina by conjugal gene transfer. The introduction of a gene for chlorophyllide a oxygenase, which is responsible for Chl b biosynthesis, into A. marina resulted in a transformant that synthesized a novel Chl species instead of Chl b. The content of the novel Chl in the transformant was approximately 10% of the total Chl, but the level of Chl a, another Chl in A. marina, did not change. The chemical structure of the novel Chl was determined to be [7-formyl]-Chl d(P) by mass spectrometry and nuclear magnetic resonance spectroscopy. [7-Formyl]-Chl d(P) is hypothesized to be produced by the combined action of chlorophyllide a oxygenase and enzyme(s) involved in Chl d biosynthesis. These results demonstrate the flexibility of the Chl biosynthetic pathway for the production of novel Chl species, indicating that a new organism with a novel Chl might be discovered in the future.
[Mh] Termos MeSH primário: Clorofila/metabolismo
Cianobactérias/enzimologia
Cianobactérias/genética
Genes Bacterianos/genética
Engenharia Metabólica/métodos
Oxigenases/genética
Transformação Genética
[Mh] Termos MeSH secundário: Vias Biossintéticas/genética
Clorofila/química
Cromatografia Líquida de Alta Pressão
Conjugação Genética
Cianobactérias/citologia
Vetores Genéticos/genética
Especificidade de Hospedeiro/genética
Oxigenases/metabolismo
Plasmídeos/genética
Prochlorothrix/enzimologia
Reprodutibilidade dos Testes
Análise Espectral
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
1406-65-1 (Chlorophyll); 60L1FX1O1U (chlorophyll d); EC 1.13.- (Oxygenases); EC 1.13.12.- (chlorophyll a oxygenase)
[Em] Mês de entrada:1210
[Cu] Atualização por classe:121115
[Lr] Data última revisão:
121115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120204
[St] Status:MEDLINE
[do] DOI:10.1093/pcp/pcs007


  4 / 24 MEDLINE  
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[PMID]:20583762
[Au] Autor:Durchan M; Herbstová M; Fuciman M; Gardian Z; Vácha F; Polívka T
[Ad] Endereço:Institute of Physical Biology, University of South Bohemia, 373 33 Nové Hrady, Czech Republic.
[Ti] Título:Carotenoids in energy transfer and quenching processes in Pcb and Pcb-PS I complexes from Prochlorothrix hollandica.
[So] Source:J Phys Chem B;114(28):9275-82, 2010 Jul 22.
[Is] ISSN:1520-5207
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Chlorophyll (Chl) a/b-binding proteins from Prochlorothrix hollandica known as Pcb antennae were studied by femtosecond transient absorption technique to identify energy transfer rates and pathways in Pcb and Pcb-PS I complexes. Carotenoids transfer energy to Chl with low efficiency of approximately 25% in Pcb complexes. Interestingly, analysis of transient absorption spectra identified a pathway from the hot S(1) state of zeaxanthin and/or beta-carotene as the major energy transfer channel between carotenoids and chlorophylls in Pcb whereas the S(2) state contributes only marginally to energy transfer. Due to energetic reasons, no energy transfer is possible via the relaxed S(1) state of carotenoids. The low overall energy transfer efficiency of carotenoids recognizes chlorophylls as the main light-harvesting pigments. Besides Chl a, presence of Chl b, which transfers energy to Chl a with nearly 100% efficiency, significantly broadens the spectral range accessible for light-harvesting and improves cross section of Pcb complexes. The major role of carotenoids in Pcb is photoprotection.
[Mh] Termos MeSH primário: Carotenoides/química
Clorofila/química
Complexo de Proteína do Fotossistema I/química
Prochlorothrix/enzimologia
[Mh] Termos MeSH secundário: Transferência de Energia
Complexo de Proteína do Fotossistema I/metabolismo
Espectrometria de Fluorescência
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Photosystem I Protein Complex); 1406-65-1 (Chlorophyll); 36-88-4 (Carotenoids); 5712ZB110R (chlorophyll b); YF5Q9EJC8Y (chlorophyll a)
[Em] Mês de entrada:1012
[Cu] Atualização por classe:121115
[Lr] Data última revisão:
121115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:100630
[St] Status:MEDLINE
[do] DOI:10.1021/jp1026724


  5 / 24 MEDLINE  
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[PMID]:19761753
[Au] Autor:Herbstová M; Litvín R; Gardian Z; Komenda J; Vácha F
[Ad] Endereço:Institute of Plant Molecular Biology, Biology Centre, Academy of Sciences of the Czech Republic, Branisovská 31, 37005 Ceské Budejovice, Czech Republic.
[Ti] Título:Localization of Pcb antenna complexes in the photosynthetic prokaryote Prochlorothrix hollandica.
[So] Source:Biochim Biophys Acta;1797(1):89-97, 2010 Jan.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The freshwater filamentous green oxyphotobacterium Prochlorothrix hollandica is an unusual oxygenic photoautotrophic cyanobacterium differing from most of the others by the presence of light-harvesting Pcb antenna binding both chlorophylls a and b and by the absence of phycobilins. The pigment-protein complexes of P. hollandica SAG 10.89 (CCAP 1490/1) were isolated from dodecylmaltoside solubilized thylakoid membranes on sucrose density gradient and characterized by biochemical, spectroscopic and immunoblotting methods. The Pcb antennae production is suppressed by high light conditions (>200 mumol photons m(-2) s(-1)) in P. hollandica. PcbC protein was found either in higher oligomeric states or coupled to PS I (forming antenna rings around PS I). PcbA and PcbB are most probably only very loosely bound to photosystems; we assume that these pigment-protein complexes function as low light-induced mobile antennae. Further, we have detected alpha-carotene in substantial quantities in P. hollandica thylakoid membranes, indicating the presence of chloroplast-like carotenoid synthetic pathway which is not present in common cyanobacteria.
[Mh] Termos MeSH primário: Fotossíntese/fisiologia
Prochlorothrix/metabolismo
[Mh] Termos MeSH secundário: Cromatografia em Gel
Cromatografia Líquida de Alta Pressão
Eletroforese em Gel de Poliacrilamida
Immunoblotting
Luz
Complexo de Proteína do Fotossistema I/isolamento & purificação
Complexo de Proteína do Fotossistema I/metabolismo
Complexo de Proteína do Fotossistema II/isolamento & purificação
Complexo de Proteína do Fotossistema II/metabolismo
Proclorófitas/metabolismo
Tilacoides/metabolismo
Tilacoides/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Photosystem I Protein Complex); 0 (Photosystem II Protein Complex)
[Em] Mês de entrada:1004
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:090919
[St] Status:MEDLINE
[do] DOI:10.1016/j.bbabio.2009.09.002


  6 / 24 MEDLINE  
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[PMID]:18201089
[Au] Autor:Hulsker R; Baranova MV; Bullerjahn GS; Ubbink M
[Ad] Endereço:Leiden Institute of Chemistry, Leiden University, Gorlaeus Laboratories, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
[Ti] Título:Dynamics in the transient complex of plastocyanin-cytochrome f from Prochlorothrix hollandica.
[So] Source:J Am Chem Soc;130(6):1985-91, 2008 Feb 13.
[Is] ISSN:1520-5126
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo: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 wild-type Pc and mutant Pc, but the chemical shift perturbations are smaller for the complex with mutant Pc. Docking calculations for the Y12G/P14L Pc-cytf complex did not produce a converged ensemble of structures. Simulations of the dynamics were performed using the observed averaged NMR parameters as input. The results indicate a surprisingly large amplitude of mobility of Y12G/P14L Pc within the complex. It is concluded that the double mutation shifts the complex further from the well-defined toward the encounter state.
[Mh] Termos MeSH primário: Simulação por Computador
Citocromos f/química
Modelos Químicos
Plastocianina/química
Prochlorothrix/química
Prochlorothrix/enzimologia
[Mh] Termos MeSH secundário: Cádmio/química
Cobre/química
Citocromos f/biossíntese
Citocromos f/isolamento & purificação
Espectroscopia de Ressonância Magnética/métodos
Espectroscopia de Ressonância Magnética/normas
Conformação Molecular
Plastocianina/biossíntese
Plastocianina/isolamento & purificação
Padrões de Referência
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
00BH33GNGH (Cadmium); 789U1901C5 (Copper); 9014-09-9 (Plastocyanin); 9035-46-5 (Cytochromes f)
[Em] Mês de entrada:0804
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:080119
[St] Status:MEDLINE
[do] DOI:10.1021/ja077453p


  7 / 24 MEDLINE  
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[PMID]:17874260
[Au] Autor:Bergmann I; Geiss-Brunschweiger U; Hagemann M; Schoor A
[Ad] Endereço:Institute of Biosciences, Aquatic Ecology, University of Rostock, Rostock, Germany.
[Ti] Título:Salinity tolerance of the chlorophyll b-synthesizing cyanobacterium Prochlorothrix hollandica strain SAG 10.89.
[So] Source:Microb Ecol;55(4):685-96, 2008 May.
[Is] ISSN:0095-3628
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Ecophysiological investigations on the salinity acclimation of the cyanobacterium Prochlorothrix hollandica SAG 10.89 led to significantly revised salinity tolerance limits. Besides potential effects of cultivation techniques, clear ion composition effects mainly explain formerly described hypersensitivity to NaCl-mediated salinity and lack of osmolyte detection. An extraordinarily broad plasticity of cellular chlorophyll a/b ratios occurred with variations of NaCl-induced salinity. Photosynthesis characteristics, pigment regulation, respiration, and biomass yield in growth medium with field-like ion composition indicated generally reduced acclimation pressure. A simultaneously significant increase in osmolyte (sucrose) accumulation indicated more efficient osmotic acclimation. Minor growth inhibition up to salinities of 10 practical salinity units enlarged the potential habitat of P. hollandica but at the most to about 300,000 km2 in the Baltic Sea. This supports probable observations of Prochlorothrix sp. in phytoplankton assemblages of open waters in Baltic Sea-monitoring studies. Brackish habitats differ from so far known habitats of Prochlorothrix spp. in turbidity, productivity, and plankton composition. Adjusted physiological features dispel fundamental doubts on the establishment of filamentous prochlorophytes in brackish waters.
[Mh] Termos MeSH primário: Clorofila/biossíntese
Prochlorothrix/efeitos dos fármacos
Prochlorothrix/crescimento & desenvolvimento
Cloreto de Sódio/farmacologia
[Mh] Termos MeSH secundário: Biomassa
Meios de Cultura
Concentração Osmolar
Fotossíntese/efeitos dos fármacos
Prochlorothrix/metabolismo
Salinidade
Sacarose/metabolismo
Microbiologia da Água
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Culture Media); 1406-65-1 (Chlorophyll); 451W47IQ8X (Sodium Chloride); 57-50-1 (Sucrose); 5712ZB110R (chlorophyll b)
[Em] Mês de entrada:0810
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:070918
[St] Status:MEDLINE


  8 / 24 MEDLINE  
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[PMID]:17174934
[Au] Autor:Boichenko VA; Pinevich AV; Stadnichuk IN
[Ad] Endereço:Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Russia. boichev@mail.ru
[Ti] Título:Association of chlorophyll a/b-binding Pcb proteins with photosystems I and II in Prochlorothrix hollandica.
[So] Source:Biochim Biophys Acta;1767(6):801-6, 2007 Jun.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Action spectra for photosystem II (PSII)-driven oxygen evolution and of photosystem I (PSI)-mediated H(2) photoproduction and photoinhibition of respiration were used to determine the participation of chlorophyll (Chl) a/b-binding Pcb proteins in the functions of pigment apparatus of Prochlorothrix hollandica. Comparison of the in situ action spectra with absorption spectra of PSII and PSI complexes isolated from the cyanobacterium Synechocystis 6803 revealed a shoulder at 650 nm that indicated presence of Chl b in the both photosystems of P. hollandica. Fitting of two action spectra to absorption spectrum of the cells showed a chlorophyll ratio of 4:1 in favor of PSI. Effective antenna sizes estimated from photochemical cross-sections of the relevant photoreactions were found to be 192+/-28 and 139+/-15 chlorophyll molecules for the competent PSI and PSII reaction centers, respectively. The value for PSI is in a quite good agreement with previous electron microscopy data for isolated Pcb-PSI supercomplexes from P. hollandica that show a trimeric PSI core surrounded by a ring of 18 Pcb subunits. The antenna size of PSII implies that the PSII core dimers are associated with approximately 14 Pcb light-harvesting proteins, and form the largest known Pcb-PSII supercomplexes.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Proteínas de Transporte/metabolismo
Complexo de Proteína do Fotossistema I/metabolismo
Complexo de Proteína do Fotossistema II/metabolismo
Prochlorothrix/metabolismo
[Mh] Termos MeSH secundário: Clorofila/metabolismo
Modelos Biológicos
Synechocystis/metabolismo
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Carrier Proteins); 0 (Photosystem I Protein Complex); 0 (Photosystem II Protein Complex); 1406-65-1 (Chlorophyll); 5712ZB110R (chlorophyll b); YF5Q9EJC8Y (chlorophyll a)
[Em] Mês de entrada:0708
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:061219
[St] Status:MEDLINE


  9 / 24 MEDLINE  
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[PMID]:16574646
[Au] Autor:Hirashima M; Satoh S; Tanaka R; Tanaka A
[Ad] Endereço:Institute of Low Temperature Science, Hokkaido University, Kita-ku, N19 W8, Sapporo 060-0819, Japan.
[Ti] Título:Pigment shuffling in antenna systems achieved by expressing prokaryotic chlorophyllide a oxygenase in Arabidopsis.
[So] Source:J Biol Chem;281(22):15385-93, 2006 Jun 02.
[Is] ISSN:0021-9258
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The organization of pigment molecules in photosystems is strictly determined. The peripheral antennae have both chlorophyll a and b, but the core antennae consist of only chlorophyll a in green plants. Furthermore, according to the recent model obtained from the crystal structure of light-harvesting chlorophyll a/b-protein complexes II (LHCII), individual chlorophyll-binding sites are occupied by either chlorophyll a or chlorophyll b. In this study, we succeeded in altering these pigment organizations by introducing a prokaryotic chlorophyll b synthesis gene (chlorophyllide a oxygenase (CAO)) into Arabidopsis. In these transgenic plants (Prochlirothrix hollandica CAO plants), approximately 40% of chlorophyll a of the core antenna complexes was replaced by chlorophyll b in both photosystems. Chlorophyll a/b ratios of LHCII also decreased from 1.3 to 0.8 in PhCAO plants. Surprisingly, these transgenic plants were capable of photosynthetic growth similar to wild type under low light conditions. These results indicate that chlorophyll organizations are not solely determined by the binding affinities, but they are also controlled by CAO. These data also suggest that strict organizations of chlorophyll molecules are not essential for photosynthesis under low light conditions.
[Mh] Termos MeSH primário: Arabidopsis/metabolismo
Oxigenases/metabolismo
[Mh] Termos MeSH secundário: Agrobacterium tumefaciens/genética
Arabidopsis/genética
Arabidopsis/ultraestrutura
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Clorofila/metabolismo
Cloroplastos/metabolismo
Cloroplastos/ultraestrutura
Genes Bacterianos
Genes de Plantas
Microscopia Eletrônica
Mutação
Oxigenases/genética
Fenótipo
Fotossíntese
Plantas Geneticamente Modificadas
Prochlorothrix/enzimologia
Prochlorothrix/genética
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Transformação Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Recombinant Proteins); 1406-65-1 (Chlorophyll); 5712ZB110R (chlorophyll b); EC 1.13.- (Oxygenases); EC 1.13.12.- (chlorophyll a oxygenase); YF5Q9EJC8Y (chlorophyll a)
[Em] Mês de entrada:0608
[Cu] Atualização por classe:121115
[Lr] Data última revisão:
121115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:060401
[St] Status:MEDLINE


  10 / 24 MEDLINE  
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[PMID]:15949978
[Au] Autor:Bumba L; Prasil O; Vacha F
[Ad] Endereço:Institute of Plant Molecular Biology, Czech Academy of Sciences, Branisovska 31, 37005 Ceske Budejovice, Czech Republic. bumba@seznam.cz
[Ti] Título:Antenna ring around trimeric Photosystem I in chlorophyll b containing cyanobacterium Prochlorothrix hollandica.
[So] Source:Biochim Biophys Acta;1708(1):1-5, 2005 Jun 01.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Prochlorothrix hollandica is one of the three known species of an unusual clade of cyanobacteria (formerly called "prochlorophytes") that contain chlorophyll a and b molecules bound to intrinsic light-harvesting antenna proteins. Here, we report the structural characterization of supramolecular complex consisting of Photosystem I (PSI) associated with the chlorophyll a/b-binding Pcb proteins. Electron microscopy and single particle image analysis of negatively stained preparations revealed that the Pcb-PSI supercomplex consists of a central trimeric PSI surrounded by a ring of 18 Pcb subunits. We conclude that the formation of the Pcb ring around trimeric PSI represents a mechanism for increasing the light-harvesting efficiency in chlorophyll b-containing cyanobacteria.
[Mh] Termos MeSH primário: Complexo de Proteína do Fotossistema I/ultraestrutura
Prochlorothrix/ultraestrutura
[Mh] Termos MeSH secundário: Centrifugação com Gradiente de Concentração
Complexos de Proteínas Captadores de Luz/química
Complexos de Proteínas Captadores de Luz/ultraestrutura
Microscopia Eletrônica
Estrutura Quaternária de Proteína
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Light-Harvesting Protein Complexes); 0 (Photosystem I Protein Complex)
[Em] Mês de entrada:0507
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:050614
[St] Status:MEDLINE



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