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[PMID]:26049454
[Au] Autor:Perlík V; Seibt J; Cranston LJ; Cogdell RJ; Lincoln CN; Savolainen J; Sanda F; Mancal T; Hauer J
[Ad] Endereço:Institute of Physics, Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, Prague 121 16, Czech Republic.
[Ti] Título:Vibronic coupling explains the ultrafast carotenoid-to-bacteriochlorophyll energy transfer in natural and artificial light harvesters.
[So] Source:J Chem Phys;142(21):212434, 2015 Jun 07.
[Is] ISSN:1089-7690
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The initial energy transfer steps in photosynthesis occur on ultrafast timescales. We analyze the carotenoid to bacteriochlorophyll energy transfer in LH2 Marichromatium purpuratum as well as in an artificial light-harvesting dyad system by using transient grating and two-dimensional electronic spectroscopy with 10 fs time resolution. We find that Förster-type models reproduce the experimentally observed 60 fs transfer times, but overestimate coupling constants, which lead to a disagreement with both linear absorption and electronic 2D-spectra. We show that a vibronic model, which treats carotenoid vibrations on both electronic ground and excited states as part of the system's Hamiltonian, reproduces all measured quantities. Importantly, the vibronic model presented here can explain the fast energy transfer rates with only moderate coupling constants, which are in agreement with structure based calculations. Counterintuitively, the vibrational levels on the carotenoid electronic ground state play the central role in the excited state population transfer to bacteriochlorophyll; resonance between the donor-acceptor energy gap and the vibrational ground state energies is the physical basis of the ultrafast energy transfer rates in these systems.
[Mh] Termos MeSH primário: Bacterioclorofilas/química
Carotenoides/química
Chromatium/química
Transferência de Energia
Complexos de Proteínas Captadores de Luz/química
[Mh] Termos MeSH secundário: Bacterioclorofilas/metabolismo
Carotenoides/metabolismo
Chromatium/metabolismo
Complexos de Proteínas Captadores de Luz/metabolismo
Análise Espectral
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacteriochlorophylls); 0 (Light-Harvesting Protein Complexes); 36-88-4 (Carotenoids)
[Em] Mês de entrada:1603
[Cu] Atualização por classe:150608
[Lr] Data última revisão:
150608
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150608
[St] Status:MEDLINE
[do] DOI:10.1063/1.4919548


  2 / 692 MEDLINE  
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[PMID]:25916149
[Au] Autor:Gorlenko VM; Briantseva IA; Lunina ON; Turova TP
[Ti] Título:[Phylogenetic position of the purple sulfur bacterium Lamprobacter modestohalophilus determined based on the data on new strains of the species].
[So] Source:Mikrobiologiia;84(1):68-77, 2015 Jan-Feb.
[Is] ISSN:0026-3656
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:Lamprobacter, the genus of halophilic purple sulfur bacteria (PSB) with the single species Lpb. modestohalophilus was described in 1979. Rod-shaped Lamprobacter cells contained gas vacuoles during the nonmotile growth phase; motile cells without gas vesicles were formed sometimes. Bacteria contained bacteriochlorophyll a and a carotenoid okenone. The names of this genus and species were included in the list of approved microbial names in 1988. Since the type strain Lpb. modestohalophilus ROI(T) has been lost, its 16S rRNA gene sequences have not been obtained. Based on analysis of the 16S rRNA genes, a new genus Halochromatium comprising the motile extremely halophilic Chromatium-like species was proposed in 1998. Members of this genus never contain gas vacuoles. In spite of the phenotypic differences between the genera Lamprobacter and Halochromatium, phylogenetic boundaries between these taxa remained undetermined. Description of a marine bacteria belonging to Lamprobacter according to its morphological andphysiological properties as a new Halochromatium species, Hch. roseum, resulted in additional complication of the taxonomic situation. The present work provides evidence for the preservation of two phenotypically and phylogenetically different genera, Lamprobacter and Halochromatium, Lpb. modestohalophilus is proposed, as the type species of the genus Lamprobacter. Characteristics of two Lpb. modestohalophilus strains were extensively investigated, and one of them (strain Sivash) was proposed as the neotype strain of the species. It was suggested to retain the genus Halochromatium as containing extremely halophilic species Hch. salexigens and Hch. glycolicum, while transfer of the weakly halophilic species Hch. roseum to the genus Lamprobacter is proposed, resulting in a new combination Lamprobacter roseus comb. nov.
[Mh] Termos MeSH primário: Chromatiaceae/classificação
Chromatium/classificação
Genes de RNAr
Filogenia
RNA Ribossômico 16S/genética
[Mh] Termos MeSH secundário: Técnicas de Tipagem Bacteriana
Bacterioclorofila A/biossíntese
Carotenoides/biossíntese
Chromatiaceae/genética
Chromatiaceae/metabolismo
Chromatium/genética
Chromatium/metabolismo
Concentração de Íons de Hidrogênio
Tolerância a Sal
Análise de Sequência de DNA
Temperatura Ambiente
[Pt] Tipo de publicação:ENGLISH ABSTRACT; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacteriochlorophyll A); 0 (RNA, Ribosomal, 16S); 0 (okenone); 36-88-4 (Carotenoids)
[Em] Mês de entrada:1505
[Cu] Atualização por classe:150428
[Lr] Data última revisão:
150428
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150429
[St] Status:MEDLINE


  3 / 692 MEDLINE  
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[PMID]:23607577
[Au] Autor:Perrin BS; Ichiye T
[Ad] Endereço:Laboratory of Computational Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
[Ti] Título:Identifying residues that cause pH-dependent reduction potentials.
[So] Source:Biochemistry;52(18):3022-4, 2013 May 07.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The pH dependence of the reduction potential E° for a metalloprotein indicates that the protonation state of at least one residue near the redox site changes and may be important for its activity. The responsible residue is usually identified by site-specific mutagenesis, which may be time-consuming. Here, the titration of E° for Chromatium vinosum high-potential iron-sulfur protein is predicted to be in good agreement with experiment using density functional theory and Poisson-Boltzmann calculations if only the sole histidine undergoes changes in protonation. The implementation of this approach into CHARMMing, a user-friendly web-based portal, allows users to identify residues in other proteins causing similar pH dependence.
[Mh] Termos MeSH primário: Concentração de Íons de Hidrogênio
[Mh] Termos MeSH secundário: Chromatium/química
Modelos Moleculares
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1307
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130424
[St] Status:MEDLINE
[do] DOI:10.1021/bi4002858


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[PMID]:22150281
[Au] Autor:Terentyev VV; Shkuropatov AY; Shkuropatova VA; Shuvalov VA; Klimov VV
[Ad] Endereço:Institute of Basic Biological Problems, Russian Academy of Sciences, ul. Institutskaya 2, 142290 Pushchino, Moscow Region, Russia. v.v.terentyev@gmail.com
[Ti] Título:Investigation of the redox interaction between Mn-bicarbonate complexes and reaction centers from Rhodobacter sphaeroides R-26, Chromatium minutissimum, and Chloroflexus aurantiacus.
[So] Source:Biochemistry (Mosc);76(12):1360-6, 2011 Dec.
[Is] ISSN:1608-3040
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The change in the dark reduction rate of photooxidized reaction centers (RC) of type II from three anoxygenic bacteria (Rhodobacter sphaeroides R-26, Chromatium minutissimum, and Chloroflexus aurantiacus) having different redox potentials of the P(+)/P pair and availability of RC for exogenous electron donors was investigated upon the addition of Mn(2+) and HCO(3)(-). It was found that the dark reduction of P(870)(+) from Rb. sphaeroides R-26 is considerably accelerated upon the combined addition of 0.5 mM MnCl(2) and 30-75 mM NaHCO(3) (as a result of formation of "low-potential" complexes [Mn(HCO(3))(2)]), while MnCl(2) and NaHCO(3) added separately had no such effect. The effect is not observed either in RC from Cf. aurantiacus (probably due to the low oxidation potential of the primary electron donor, P(865), which results in thermodynamic difficulties of the redox interaction between P(865)(+) and Mn(2+)) or in RC from Ch. minutissimum (apparently due to the presence of the RC-bound cytochrome preventing the direct interaction between P(870)(+) and Mn(2+)). The absence of acceleration of the dark reduction of P(870)(+) in the RC of Rb. sphaeroides R-26 when Mn(2+) and HCO(3)(-) were replaced by Mg(2+) or Ca(2+) and by formate, oxalate, or acetate, respectively, reveals the specificity of the Mn2+-bicarbonate complexes for the redox interaction with P(+). The results of this work might be considered as experimental evidence for the hypothesis of the participation of Mn(2+) complexes in the evolutionary origin of the inorganic core of the water oxidizing complex of photosystem II.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Cloretos/metabolismo
Chloroflexus/metabolismo
Chromatium/metabolismo
Compostos de Manganês/metabolismo
Complexo de Proteína do Fotossistema II/metabolismo
Rhodobacter sphaeroides/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Chloroflexus/química
Chloroflexus/genética
Chloroflexus/efeitos da radiação
Chromatium/química
Chromatium/genética
Chromatium/efeitos da radiação
Cinética
Luz
Oxirredução
Complexo de Proteína do Fotossistema II/química
Complexo de Proteína do Fotossistema II/genética
Rhodobacter sphaeroides/química
Rhodobacter sphaeroides/genética
Rhodobacter sphaeroides/efeitos da radiação
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Chlorides); 0 (Manganese Compounds); 0 (Photosystem II Protein Complex); QQE170PANO (manganese chloride)
[Em] Mês de entrada:1204
[Cu] Atualização por classe:121115
[Lr] Data última revisão:
121115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:111214
[St] Status:MEDLINE
[do] DOI:10.1134/S0006297911120091


  5 / 692 MEDLINE  
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[PMID]:20455432
[Au] Autor:Pavlova IuO; Hnatush SO; Hudz' SP
[Ti] Título:[Physilogical and biochemical properties of bacteria of Chromatium genus, isolated from water bodies enriched with hydrogen sulfide].
[So] Source:Mikrobiol Z;71(6):43-53, 2009 Nov-Dec.
[Is] ISSN:1028-0987
[Cp] País de publicação:Ukraine
[La] Idioma:ukr
[Ab] Resumo:Pure cultures of purple sulfur bacteria, which were attributed to genus Chromatium, were isolated from water bodies of the Yavoriv sulfur deposit. Both cultures perform anoxygenic photosynthesis and contain bacteriochlorophyll a and carotenoids of spirilloxanthin group. Isolated bacteria grow photolithoauthotrophically, photolithoheterotrophically and photoorganoheterotrophically. Hydrogen sulphide, sulfur and thiosulfate were used as inorganic electron donors. Bacteria were resistant to high hydrogen sulphide concentrations and assimilated it effectively in the process of anoxygenic photosynthesis. Isolated bacteria are considered as promising models for creation of biotechnologic ecosystems, which will be used for treatment of media polluted with sulfur compounds.
[Mh] Termos MeSH primário: Chromatium
Água Doce/análise
Sulfeto de Hidrogênio/análise
Microbiologia da Água
Poluentes Químicos da Água/análise
[Mh] Termos MeSH secundário: Biodegradação Ambiental
Chromatium/isolamento & purificação
Chromatium/metabolismo
Chromatium/fisiologia
Água Doce/química
Água Doce/microbiologia
Microscopia Eletrônica de Transmissão
Pigmentos Biológicos/isolamento & purificação
Espectrofotometria
[Pt] Tipo de publicação:ENGLISH ABSTRACT; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Pigments, Biological); 0 (Water Pollutants, Chemical); YY9FVM7NSN (Hydrogen Sulfide)
[Em] Mês de entrada:1006
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:100512
[St] Status:MEDLINE


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[PMID]:19423634
[Au] Autor:Franz B; Gehrke T; Lichtenberg H; Hormes J; Dahl C; Prange A
[Ad] Endereço:Hochschule Niederrhein, Mikrobiologie und Lebensmittelhygiene, 41065 Mönchengladbach, Germany.
[Ti] Título:Unexpected extracellular and intracellular sulfur species during growth of Allochromatium vinosum with reduced sulfur compounds.
[So] Source:Microbiology;155(Pt 8):2766-74, 2009 Aug.
[Is] ISSN:1350-0872
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Before its uptake and oxidation by purple sulfur bacteria, elemental sulfur probably first has to be mobilized. To obtain more insight into this mobilization process in the phototrophic purple sulfur bacterium Allochromatium vinosum, we used HPLC analysis and X-ray absorption near-edge structure (XANES) spectroscopy for the detection and identification of sulfur compounds in culture supernatants and bacterial cells. We intended to identify soluble sulfur compounds that specifically occur during growth on elemental sulfur, and therefore compared spectra of cultures grown on sulfur with those of cultures grown on sulfide or thiosulfate. While various unexpected oxidized organic sulfur species (sulfones, C-SO(2)-C, and sulfonates, C-SO(3)(-)) were observed via XANES spectroscopy in the supernatants, we obtained evidence for the presence of monosulfane sulfonic acids inside the bacterial cells by HPLC analysis. The concentrations of the latter compounds showed a tight correlation with the content of intracellular sulfur, reaching their maximum when sulfur began to be oxidized. None of the detected sulfur compounds appeared to be a specific soluble intermediate or product of elemental sulfur mobilization. It therefore seems unlikely that mobilization of elemental sulfur by purple sulfur bacteria involves excretion of soluble sulfur-containing substances that would be able to act on substrate distant from the cells.
[Mh] Termos MeSH primário: Chromatium/química
Chromatium/metabolismo
Espaço Extracelular/química
Espaço Intracelular/química
Enxofre/metabolismo
[Mh] Termos MeSH secundário: Chromatium/crescimento & desenvolvimento
Cromatografia Líquida de Alta Pressão
Meios de Cultura/química
Periplasma/química
Periplasma/metabolismo
Análise Espectral
Sulfetos/química
Sulfetos/metabolismo
Sulfonas/química
Sulfonas/metabolismo
Ácidos Sulfônicos/química
Ácidos Sulfônicos/metabolismo
Enxofre/química
Tiossulfatos/química
Tiossulfatos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Culture Media); 0 (Sulfides); 0 (Sulfones); 0 (Sulfonic Acids); 0 (Thiosulfates); 70FD1KFU70 (Sulfur)
[Em] Mês de entrada:0910
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:090509
[St] Status:MEDLINE
[do] DOI:10.1099/mic.0.027904-0


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[PMID]:19397681
[Au] Autor:Halm H; Musat N; Lam P; Langlois R; Musat F; Peduzzi S; Lavik G; Schubert CJ; Sinha B; Singha B; LaRoche J; Kuypers MM
[Ad] Endereço:Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany. hhalm@mpi-bremen.de
[Ti] Título:Co-occurrence of denitrification and nitrogen fixation in a meromictic lake, Lake Cadagno (Switzerland).
[So] Source:Environ Microbiol;11(8):1945-58, 2009 Aug.
[Is] ISSN:1462-2920
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The nitrogen cycling of Lake Cadagno was investigated by using a combination of biogeochemical and molecular ecological techniques. In the upper oxic freshwater zone inorganic nitrogen concentrations were low (up to approximately 3.4 microM nitrate at the base of the oxic zone), while in the lower anoxic zone there were high concentrations of ammonium (up to 40 microM). Between these zones, a narrow zone was characterized by no measurable inorganic nitrogen, but high microbial biomass (up to 4 x 10(7) cells ml(-1)). Incubation experiments with (15)N-nitrite revealed nitrogen loss occurring in the chemocline through denitrification (approximately 3 nM N h(-1)). At the same depth, incubations experiments with (15)N(2)- and (13)C(DIC)-labelled bicarbonate, indicated substantial N(2) fixation (31.7-42.1 pM h(-1)) and inorganic carbon assimilation (40-85 nM h(-1)). Catalysed reporter deposition fluorescence in situ hybridization (CARD-FISH) and sequencing of 16S rRNA genes showed that the microbial community at the chemocline was dominated by the phototrophic green sulfur bacterium Chlorobium clathratiforme. Phylogenetic analyses of the nifH genes expressed as mRNA revealed a high diversity of N(2) fixers, with the highest expression levels right at the chemocline. The majority of N(2) fixers were related to Chlorobium tepidum/C. phaeobacteroides. By using Halogen In Situ Hybridization-Secondary Ion Mass Spectroscopy (HISH-SIMS), we could for the first time directly link Chlorobium to N(2) fixation in the environment. Moreover, our results show that N(2) fixation could partly compensate for the N loss and that both processes occur at the same locale at the same time as suggested for the ancient Ocean.
[Mh] Termos MeSH primário: Água Doce/microbiologia
Fixação de Nitrogênio
Nitrogênio/análise
[Mh] Termos MeSH secundário: Dióxido de Carbono/análise
Chlorobium/classificação
Chlorobium/isolamento & purificação
Chlorobium/metabolismo
Chromatium/isolamento & purificação
Chromatium/metabolismo
Água Doce/química
Hibridização In Situ
Nitritos/análise
Oxirredutases/genética
Oxirredutases/metabolismo
Filogenia
Compostos de Amônio Quaternário/análise
RNA Ribossômico 16S/metabolismo
Suíça
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nitrites); 0 (Quaternary Ammonium Compounds); 0 (RNA, Ribosomal, 16S); 142M471B3J (Carbon Dioxide); EC 1.- (Oxidoreductases); EC 1.18.6.1 (nitrogenase reductase); N762921K75 (Nitrogen)
[Em] Mês de entrada:0909
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:090429
[St] Status:MEDLINE
[do] DOI:10.1111/j.1462-2920.2009.01917.x


  8 / 692 MEDLINE  
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[PMID]:18600468
[Au] Autor:Essien JP; Antai SP
[Ad] Endereço:Department of Microbiology, University of Uyo, P.M.B1017 Uyo, Nigeria. jomato652003@yahoo.com
[Ti] Título:Chromatium species: an emerging bioindicator of crude oil pollution of tidal mud flats in the Niger Delta mangrove ecosystem, Nigeria.
[So] Source:Environ Monit Assess;153(1-4):95-102, 2009 Jun.
[Is] ISSN:1573-2959
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Establishing microbiological indices for the monitoring of environmental decay by crude oil pollution in the Niger Delta region has been a major concern of our current researches. Chromatium species, a purple, Gram positive pleomorphic, motile, microaerophlic sulfur bacterium offers a good potential for use in the assessment of the short term effects of oil pollution of tidal mud flats in the Niger Delta mangrove ecosystem. Its response to the November 22, 2003 spillage at the Qua Iboe Estuary and the adjoining Cross River Estuary was investigated. Our results have revealed that the sulphur bacterium is easily identified and widely distributed in the epipellic sediment of the mangrove ecosystem but very sensitive to hydrocarbon pollution. The bacterium was readily detected in the tidal mud flats containing as much as 2.0 mg kg(-1) but not detected in sediment with THC level of 3.65 mg kg(-1) and above. It is thus, suggestive that the threshold and lethal limits of effect of hydrocarbons against the sulfur bacterium lies between 2.04 and 3.65 mg kg(-1). These imply that in any case of crude oil pollution that Chromatium is not detected during monitoring the THC levels of the sediment may have been raised to a level close to or above 3.65 mg kg(-1). Statistical analysis of the relationship between THC level and density of Chromatium in sediment revealed a significant (p < 0.05) negative relationship (r = -0.85) in Qua Iboe mangrove ecosystem as against an insignificant (p > 0.05) relationship (r = -0.41) recorded for the Cross River mangrove ecosystem which served as the control. The result indicates that oil pollution affect the homeostatic status of Chromatium in tidal mud flats despite its even distribution (R2 = 71.4%). The finding though not definitive may contribute to the hierarchical process of oil pollution assessment in the Niger Delta region of Nigeria. However, its effective utilization will require not only the development of a selective medium for enumeration and isolation of the bacterium but also the establishment of a defined dose-response relationship under controlled conditions which requires further research.
[Mh] Termos MeSH primário: Chromatium/efeitos dos fármacos
Chromatium/crescimento & desenvolvimento
Ecossistema
Monitoramento Ambiental/métodos
Poluição Ambiental/análise
Petróleo/toxicidade
Poluentes Químicos da Água/toxicidade
[Mh] Termos MeSH secundário: Geografia
Nigéria
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Petroleum); 0 (Water Pollutants, Chemical)
[Em] Mês de entrada:0907
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:080705
[St] Status:MEDLINE
[do] DOI:10.1007/s10661-008-0339-x


  9 / 692 MEDLINE  
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[PMID]:18692688
[Au] Autor:Plass C; Oakes C; Blum W; Marcucci G
[Ad] Endereço:German Cancer Research Center, Division of Toxicology and Cancer Risk Factors, Heidelberg, Germany. c.plass@dkfz.de
[Ti] Título:Epigenetics in acute myeloid leukemia.
[So] Source:Semin Oncol;35(4):378-87, 2008 Aug.
[Is] ISSN:0093-7754
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Acute myeloid leukemia (AML) is a disease characterized by uncontrolled proliferation of clonal neoplastic hematopoietic precursor cells. This leads to the disruption of normal hematopoiesis and bone marrow failure. Major breakthroughs in the past have contributed to our understanding of the genetic failures and the changed biology in AML cells that underlie the initiation and progression of the disease. It is now recognized that not only genetic but also epigenetic alterations are similarly important in this process. Since these alterations do not change the DNA sequences and are pharmacologically reversible, they have been regarded as optimal targets for what is now known as epigenetic therapy. In this review, we will discuss our current understanding of normal epigenetic processes, outline our knowledge of epigenetic alterations in AML, and discuss how this information is being used to improve current therapy of this disease.
[Mh] Termos MeSH primário: Epigênese Genética
Leucemia Mieloide Aguda/genética
[Mh] Termos MeSH secundário: Montagem e Desmontagem da Cromatina
Chromatium/fisiologia
Metilação de DNA
Inativação Gênica
Inibidores de Histona Desacetilases
Histonas/fisiologia
Seres Humanos
Leucemia Mieloide Aguda/terapia
RNA não Traduzido/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; REVIEW
[Nm] Nome de substância:
0 (Histone Deacetylase Inhibitors); 0 (Histones); 0 (RNA, Untranslated)
[Em] Mês de entrada:0809
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:080812
[St] Status:MEDLINE
[do] DOI:10.1053/j.seminoncol.2008.04.008


  10 / 692 MEDLINE  
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[PMID]:17977556
[Au] Autor:Van Petegem F; De Vos D; Savvides S; Vergauwen B; Van Beeumen J
[Ad] Endereço:Laboratory of Protein Biochemistry and Protein Engineering, Ghent University, 9000 Ghent, Belgium. filip.vanpetegem@gmail.com
[Ti] Título:Understanding nicotinamide dinucleotide cofactor and substrate specificity in class I flavoprotein disulfide oxidoreductases: crystallographic analysis of a glutathione amide reductase.
[So] Source:J Mol Biol;374(4):883-9, 2007 Dec 07.
[Is] ISSN:1089-8638
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Glutathione reductase (GR) plays a vital role in maintaining the antioxidant levels of the cytoplasm by catalyzing the reduction of glutathione disulfide to reduced glutathione, thereby using NADPH and flavin adenine dinucleotide as cofactors. Chromatiaceae have evolved an unusual homolog that prefers both a modified substrate (glutathione amide disulfide [GASSAG]) and a different cofactor (NADH). Herein, we present the crystal structure of the Chromatium gracile glutathione amide reductase (GAR) both alone and in complex with NAD(+). An altered charge distribution in the GASSAG binding pocket explains the difference in substrate specificity. The NADH binding pocket of GAR differs from that of wild-type GR as well as that of a low active GR that was engineered to mimic NADH binding. Based on the GAR structure, we propose two attractive rationales for producing an efficient GR enzyme with NADH specificity.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Chromatium/enzimologia
Flavoproteínas/química
Glutationa Redutase/química
Peroxidases/química
[Mh] Termos MeSH secundário: Sítios de Ligação
Cristalografia por Raios X
Modelos Moleculares
NAD/química
Oxirredução
Conformação Proteica
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Flavoproteins); 0U46U6E8UK (NAD); EC 1.11.1.- (Peroxidases); EC 1.11.1.- (garB protein, Marichromatium gracile); EC 1.8.1.7 (Glutathione Reductase)
[Em] Mês de entrada:0803
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:071106
[St] Status:MEDLINE



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