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  1 / 15 MEDLINE  
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[PMID]:25662973
[Au] Autor:Smith JA; Aklujkar M; Risso C; Leang C; Giloteaux L; Holmes DE
[Ad] Endereço:Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA.
[Ti] Título:Mechanisms involved in Fe(III) respiration by the hyperthermophilic archaeon Ferroglobus placidus.
[So] Source:Appl Environ Microbiol;81(8):2735-44, 2015 Apr.
[Is] ISSN:1098-5336
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The hyperthermophilic archaeon Ferroglobus placidus can utilize a wide variety of electron donors, including hydrocarbons and aromatic compounds, with Fe(III) serving as an electron acceptor. In Fe(III)-reducing bacteria that have been studied to date, this process is mediated by c-type cytochromes and type IV pili. However, there currently is little information available about how this process is accomplished in archaea. In silico analysis of the F. placidus genome revealed the presence of 30 genes coding for putative c-type cytochrome proteins (more than any other archaeon that has been sequenced to date), five of which contained 10 or more heme-binding motifs. When cell extracts were analyzed by SDS-PAGE followed by heme staining, multiple bands corresponding to c-type cytochromes were detected. Different protein expression patterns were observed in F. placidus cells grown on soluble and insoluble iron forms. In order to explore this result further, transcriptomic studies were performed. Eight genes corresponding to multiheme c-type cytochromes were upregulated when F. placidus was grown with insoluble Fe(III) oxide compared to soluble Fe(III) citrate as an electron acceptor. Numerous archaella (archaeal flagella) also were observed on Fe(III)-grown cells, and genes coding for two type IV pilin-like domain proteins were differentially expressed in Fe(III) oxide-grown cells. This study provides insight into the mechanisms for dissimilatory Fe(III) respiration by hyperthermophilic archaea.
[Mh] Termos MeSH primário: Proteínas Arqueais/genética
Archaeoglobales/genética
Citocromos c/genética
Compostos Férricos/metabolismo
Regulação da Expressão Gênica
Genoma Arqueal
[Mh] Termos MeSH secundário: Proteínas Arqueais/metabolismo
Archaeoglobales/metabolismo
Citocromos c/metabolismo
Dados de Sequência Molecular
Oxirredução
Proteoma
Análise de Sequência de DNA
Transcriptoma
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Archaeal Proteins); 0 (Ferric Compounds); 0 (Proteome); 9007-43-6 (Cytochromes c)
[Em] Mês de entrada:1512
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150210
[St] Status:MEDLINE
[do] DOI:10.1128/AEM.04038-14


  2 / 15 MEDLINE  
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[PMID]:25630364
[Au] Autor:Schmid G; René SB; Boll M
[Ad] Endereço:Microbiology, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg, 79104, Germany.
[Ti] Título:Enzymes of the benzoyl-coenzyme A degradation pathway in the hyperthermophilic archaeon Ferroglobus placidus.
[So] Source:Environ Microbiol;17(9):3289-300, 2015 Sep.
[Is] ISSN:1462-2920
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The Fe(III)-respiring Ferroglobus placidus is the only known archaeon and hyperthermophile for which a complete degradation of aromatic substrates to CO2 has been reported. Recent genome and transcriptome analyses proposed a benzoyl-coenzyme A (CoA) degradation pathway similar to that found in the phototrophic Rhodopseudomonas palustris, which involves a cyclohex-1-ene-1-carboxyl-CoA (1-enoyl-CoA) forming, ATP-dependent key enzyme benzoyl-CoA reductase (BCR). In this work, we demonstrate, by first in vitro studies, that benzoyl-CoA is ATP-dependently reduced by two electrons to cyclohexa-1,5-dienoyl-CoA (1,5-dienoyl-CoA), which is further degraded by hydration to 6-hydroxycyclohex-1-ene-1-carboxyl-CoA (6-OH-1-enoyl-CoA); upon addition of NAD(+) , the latter was subsequently converted to ß-oxidation intermediates. The four candidate genes of BCR were heterologously expressed, and the enriched, oxygen-sensitive enzyme catalysed the two-electron reduction of benzoyl-CoA to 1,5-dienoyl-CoA. A gene previously assigned to a 2,3-didehydropimeloyl-CoA hydratase was heterologously expressed and shown to act as a typical 1,5-dienoyl-CoA hydratase that does not accept 1-enoyl-CoA. A gene previously assigned to a 1-enoyl-CoA hydratase was heterologously expressed and identified to code for a bifunctional crotonase/3-OH-butyryl-CoA dehydrogenase. In summary, the results consistently provide biochemical evidence that F. placidus and probably other archaea predominantly degrade aromatics via the Thauera/Azoarcus type and not or only to a minor extent via the predicted R. palustris-type benzoyl-CoA degradation pathway.
[Mh] Termos MeSH primário: Acil Coenzima A/metabolismo
Archaeoglobales/enzimologia
Redes e Vias Metabólicas/fisiologia
[Mh] Termos MeSH secundário: Anaerobiose
Archaeoglobales/genética
Coenzima A/metabolismo
Enoil-CoA Hidratase/metabolismo
Compostos Férricos/metabolismo
Hidroliases/metabolismo
Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo
Thauera/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Acyl Coenzyme A); 0 (Ferric Compounds); 6756-74-7 (benzoyl-coenzyme A); EC 1.3.- (Oxidoreductases Acting on CH-CH Group Donors); EC 1.3.99.- (benzoyl-coenzyme A reductase (dearomatizing)); EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.- (cyclohexa-1,5-diene-1-carboxyl-CoA hydratase); EC 4.2.1.17 (Enoyl-CoA Hydratase); SAA04E81UX (Coenzyme A)
[Em] Mês de entrada:1604
[Cu] Atualização por classe:150909
[Lr] Data última revisão:
150909
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150130
[St] Status:MEDLINE
[do] DOI:10.1111/1462-2920.12785


  3 / 15 MEDLINE  
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[PMID]:25416759
[Au] Autor:Mardanov AV; Slododkina GB; Slobodkin AI; Beletsky AV; Gavrilov SN; Kublanov IV; Bonch-Osmolovskaya EA; Skryabin KG; Ravin NV
[Ad] Endereço:Bioengineering Centre, Russian Academy of Sciences, Moscow, Russia.
[Ti] Título:The Geoglobus acetivorans genome: Fe(III) reduction, acetate utilization, autotrophic growth, and degradation of aromatic compounds in a hyperthermophilic archaeon.
[So] Source:Appl Environ Microbiol;81(3):1003-12, 2015 Feb.
[Is] ISSN:1098-5336
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Geoglobus acetivorans is a hyperthermophilic anaerobic euryarchaeon of the order Archaeoglobales isolated from deep-sea hydrothermal vents. A unique physiological feature of the members of the genus Geoglobus is their obligate dependence on Fe(III) reduction, which plays an important role in the geochemistry of hydrothermal systems. The features of this organism and its complete 1,860,815-bp genome sequence are described in this report. Genome analysis revealed pathways enabling oxidation of molecular hydrogen, proteinaceous substrates, fatty acids, aromatic compounds, n-alkanes, and organic acids, including acetate, through anaerobic respiration linked to Fe(III) reduction. Consistent with the inability of G. acetivorans to grow on carbohydrates, the modified Embden-Meyerhof pathway encoded by the genome is incomplete. Autotrophic CO2 fixation is enabled by the Wood-Ljungdahl pathway. Reduction of insoluble poorly crystalline Fe(III) oxide depends on the transfer of electrons from the quinone pool to multiheme c-type cytochromes exposed on the cell surface. Direct contact of the cells and Fe(III) oxide particles could be facilitated by pilus-like appendages. Genome analysis indicated the presence of metabolic pathways for anaerobic degradation of aromatic compounds and n-alkanes, although an ability of G. acetivorans to grow on these substrates was not observed in laboratory experiments. Overall, our results suggest that Geoglobus species could play an important role in microbial communities of deep-sea hydrothermal vents as lithoautotrophic producers. An additional role as decomposers would close the biogeochemical cycle of carbon through complete mineralization of various organic compounds via Fe(III) respiration.
[Mh] Termos MeSH primário: Acetatos/metabolismo
Archaeoglobales/genética
Processos Autotróficos
Compostos Ferrosos/metabolismo
Genoma Arqueal
Redes e Vias Metabólicas
Hidrocarbonetos Aromáticos Policíclicos/metabolismo
[Mh] Termos MeSH secundário: Biotransformação
DNA Arqueal/química
DNA Arqueal/genética
Dados de Sequência Molecular
Oxirredução
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Acetates); 0 (DNA, Archaeal); 0 (Ferrous Compounds); 0 (Polycyclic Aromatic Hydrocarbons)
[Em] Mês de entrada:1509
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141123
[St] Status:MEDLINE
[do] DOI:10.1128/AEM.02705-14


  4 / 15 MEDLINE  
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[PMID]:25269449
[Au] Autor:Aklujkar M; Risso C; Smith J; Beaulieu D; Dubay R; Giloteaux L; DiBurro K; Holmes D
[Ad] Endereço:Department of Biological Sciences, Towson University, Towson, MD, USA.
[Ti] Título:Anaerobic degradation of aromatic amino acids by the hyperthermophilic archaeon Ferroglobus placidus.
[So] Source:Microbiology;160(Pt 12):2694-709, 2014 Dec.
[Is] ISSN:1465-2080
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Ferroglobus placidus was discovered to oxidize completely the aromatic amino acids tyrosine, phenylalanine and tryptophan when Fe(III) oxide was provided as an electron acceptor. This property had not been reported previously for a hyperthermophilic archaeon. It appeared that F. placidus follows a pathway for phenylalanine and tryptophan degradation similar to that of mesophilic nitrate-reducing bacteria, Thauera aromatica and Aromatoleum aromaticum EbN1. Phenylacetate, 4-hydroxyphenylacetate and indole-3-acetate were formed during anaerobic degradation of phenylalanine, tyrosine and tryptophan, respectively. Candidate genes for enzymes involved in the anaerobic oxidation of phenylalanine to phenylacetate (phenylalanine transaminase, phenylpyruvate decarboxylase and phenylacetaldehyde : ferredoxin oxidoreductase) were identified in the F. placidus genome. In addition, transcription of candidate genes for the anaerobic phenylacetate degradation, benzoyl-CoA degradation and glutaryl-CoA degradation pathways was significantly upregulated in microarray and quantitative real-time-PCR studies comparing phenylacetate-grown cells with acetate-grown cells. These results suggested that the general strategies for anaerobic degradation of aromatic amino acids are highly conserved amongst bacteria and archaea living in both mesophilic and hyperthermophilic environments. They also provided insights into the diverse metabolism of Archaeoglobaceae species living in hyperthermophilic environments.
[Mh] Termos MeSH primário: Aminoácidos Aromáticos/metabolismo
Archaeoglobales/metabolismo
[Mh] Termos MeSH secundário: Anaerobiose
Biotransformação
Perfilação da Expressão Gênica
Ácidos Indolacéticos/metabolismo
Redes e Vias Metabólicas/genética
Análise em Microsséries
Dados de Sequência Molecular
Oxirredução
Fenilacetatos/metabolismo
Reação em Cadeia da Polimerase em Tempo Real
Análise de Sequência de DNA
[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:
0 (Amino Acids, Aromatic); 0 (Indoleacetic Acids); 0 (Phenylacetates); 3233-32-7 (4-hydroxyphenylacetate); 6U1S09C61L (indoleacetic acid); ER5I1W795A (phenylacetic acid)
[Em] Mês de entrada:1510
[Cu] Atualização por classe:151124
[Lr] Data última revisão:
151124
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141002
[St] Status:MEDLINE
[do] DOI:10.1099/mic.0.083261-0


  5 / 15 MEDLINE  
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[PMID]:23728807
[Au] Autor:Manzella MP; Reguera G; Kashefi K
[Ad] Endereço:Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA.
[Ti] Título:Extracellular electron transfer to Fe(III) oxides by the hyperthermophilic archaeon Geoglobus ahangari via a direct contact mechanism.
[So] Source:Appl Environ Microbiol;79(15):4694-700, 2013 Aug.
[Is] ISSN:1098-5336
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The microbial reduction of Fe(III) plays an important role in the geochemistry of hydrothermal systems, yet it is poorly understood at the mechanistic level. Here we show that the obligate Fe(III)-reducing archaeon Geoglobus ahangari uses a direct-contact mechanism for the reduction of Fe(III) oxides to magnetite at 85°C. Alleviating the need to directly contact the mineral with the addition of a chelator or the electron shuttle anthraquinone-2,6-disulfonate (AQDS) stimulated Fe(III) reduction. In contrast, entrapment of the oxides within alginate beads to prevent cell contact with the electron acceptor prevented Fe(III) reduction and cell growth unless AQDS was provided. Furthermore, filtered culture supernatant fluids had no effect on Fe(III) reduction, ruling out the secretion of an endogenous mediator too large to permeate the alginate beads. Consistent with a direct contact mechanism, electron micrographs showed cells in intimate association with the Fe(III) mineral particles, which once dissolved revealed abundant curled appendages. The cells also produced several heme-containing proteins. Some of them were detected among proteins sheared from the cell's outer surface and were required for the reduction of insoluble Fe(III) oxides but not for the reduction of the soluble electron acceptor Fe(III) citrate. The results thus support a mechanism in which the cells directly attach and transfer electrons to the Fe(III) oxides using redox-active proteins exposed on the cell surface. This strategy confers on G. ahangari a competitive advantage for accessing and reducing Fe(III) oxides under the extreme physical and chemical conditions of hot ecosystems.
[Mh] Termos MeSH primário: Antraquinonas/metabolismo
Archaeoglobales/metabolismo
Transporte de Elétrons
Compostos Férricos/metabolismo
[Mh] Termos MeSH secundário: Temperatura Alta
México
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anthraquinones); 0 (Ferric Compounds); 0 (anthraquinone-2,6-disulfonate)
[Em] Mês de entrada:1310
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130604
[St] Status:MEDLINE
[do] DOI:10.1128/AEM.01566-13


  6 / 15 MEDLINE  
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[PMID]:23555835
[Au] Autor:Peacock JP; Cole JK; Murugapiran SK; Dodsworth JA; Fisher JC; Moser DP; Hedlund BP
[Ad] Endereço:School of Life Sciences, University of Nevada, Las Vegas, Nevada, United States of America.
[Ti] Título:Pyrosequencing reveals high-temperature cellulolytic microbial consortia in Great Boiling Spring after in situ lignocellulose enrichment.
[So] Source:PLoS One;8(3):e59927, 2013.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:To characterize high-temperature cellulolytic microbial communities, two lignocellulosic substrates, ammonia fiber-explosion-treated corn stover and aspen shavings, were incubated at average temperatures of 77 and 85°C in the sediment and water column of Great Boiling Spring, Nevada. Comparison of 109,941 quality-filtered 16S rRNA gene pyrosequences (pyrotags) from eight enrichments to 37,057 quality-filtered pyrotags from corresponding natural samples revealed distinct enriched communities dominated by phylotypes related to cellulolytic and hemicellulolytic Thermotoga and Dictyoglomus, cellulolytic and sugar-fermenting Desulfurococcales, and sugar-fermenting and hydrogenotrophic Archaeoglobales. Minor enriched populations included close relatives of hydrogenotrophic Thermodesulfobacteria, the candidate bacterial phylum OP9, and candidate archaeal groups C2 and DHVE3. Enrichment temperature was the major factor influencing community composition, with a negative correlation between temperature and richness, followed by lignocellulosic substrate composition. This study establishes the importance of these groups in the natural degradation of lignocellulose at high temperatures and suggests that a substantial portion of the diversity of thermophiles contributing to consortial cellulolysis may be contained within lineages that have representatives in pure culture.
[Mh] Termos MeSH primário: Genes Arqueais
Fontes Termais/microbiologia
Lignina/química
Consórcios Microbianos/genética
Análise de Sequência de DNA/métodos
[Mh] Termos MeSH secundário: Archaeoglobales/genética
Biodiversidade
Desulfurococcales/genética
Temperatura Alta
Nevada
Filogenia
Polissacarídeos/química
RNA Ribossômico 16S/metabolismo
Árvores/microbiologia
Água/química
Microbiologia da Água
Zea mays/microbiologia
[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:
0 (Polysaccharides); 0 (RNA, Ribosomal, 16S); 059QF0KO0R (Water); 11132-73-3 (lignocellulose); 8024-50-8 (hemicellulose); 9005-53-2 (Lignin)
[Em] Mês de entrada:1401
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130405
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0059927


  7 / 15 MEDLINE  
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[PMID]:22102245
[Au] Autor:Osawa T; Inanaga H; Kimura S; Terasaka N; Suzuki T; Numata T
[Ad] Endereço:Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba-shi, Ibaraki 305-8566, Japan.
[Ti] Título:Crystallization and preliminary X-ray diffraction analysis of an archaeal tRNA-modification enzyme, TiaS, complexed with tRNA(Ile2) and ATP.
[So] Source:Acta Crystallogr Sect F Struct Biol Cryst Commun;67(Pt 11):1414-6, 2011 Nov 01.
[Is] ISSN:1744-3091
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The cytidine at the first anticodon position of archaeal tRNA(Ile2), which decodes the isoleucine AUA codon, is modified to 2-agmatinylcytidine (agm(2)C) to guarantee the fidelity of protein biosynthesis. This post-transcriptional modification is catalyzed by tRNA(Ile)-agm(2)C synthetase (TiaS) using ATP and agmatine as substrates. Archaeoglobus fulgidus TiaS was overexpressed in Escherichia coli cells and purified. tRNA(Ile2) was prepared by in vitro transcription with T7 RNA polymerase. TiaS was cocrystallized with both tRNA(Ile2) and ATP by the vapour-diffusion method. The crystals of the TiaS-tRNA(Ile2)-ATP complex diffracted to 2.9 Å resolution using synchrotron radiation at the Photon Factory. The crystals belonged to the primitive hexagonal space group P3(2)21, with unit-cell parameters a = b = 131.1, c = 86.6 Å. The asymmetric unit is expected to contain one TiaS-tRNA(Ile2)-ATP complex, with a Matthews coefficient of 2.8 Å(3) Da(-1) and a solvent content of 61%.
[Mh] Termos MeSH primário: Trifosfato de Adenosina/química
Archaeoglobales/enzimologia
Isoleucina-tRNA Ligase/química
RNA de Transferência de Isoleucina/química
[Mh] Termos MeSH secundário: Trifosfato de Adenosina/metabolismo
Cristalização
Cristalografia por Raios X
Isoleucina-tRNA Ligase/metabolismo
Ligação Proteica
RNA de Transferência de Isoleucina/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (RNA, Transfer, Ile); 8L70Q75FXE (Adenosine Triphosphate); EC 6.1.1.5 (Isoleucine-tRNA Ligase)
[Em] Mês de entrada:1202
[Cu] Atualização por classe:150129
[Lr] Data última revisão:
150129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:111122
[St] Status:MEDLINE
[do] DOI:10.1107/S1744309111034890


  8 / 15 MEDLINE  
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[PMID]:21742914
[Au] Autor:Holmes DE; Risso C; Smith JA; Lovley DR
[Ad] Endereço:Department of Microbiology, 203N Morrill Science Center IVN, University of Massachusetts-Amherst, Amherst, MA 01003, USA. dholmes@microbio.umass.edu
[Ti] Título:Anaerobic oxidation of benzene by the hyperthermophilic archaeon Ferroglobus placidus.
[So] Source:Appl Environ Microbiol;77(17):5926-33, 2011 Sep.
[Is] ISSN:1098-5336
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Anaerobic benzene oxidation coupled to the reduction of Fe(III) was studied in Ferroglobus placidus in order to learn more about how such a stable molecule could be metabolized under strict anaerobic conditions. F. placidus conserved energy to support growth at 85°C in a medium with benzene provided as the sole electron donor and Fe(III) as the sole electron acceptor. The stoichiometry of benzene loss and Fe(III) reduction, as well as the conversion of [(14)C]benzene to [(14)C]carbon dioxide, was consistent with complete oxidation of benzene to carbon dioxide with electron transfer to Fe(III). Benzoate, but not phenol or toluene, accumulated at low levels during benzene metabolism, and [(14)C]benzoate was produced from [(14)C]benzene. Analysis of gene transcript levels revealed increased expression of genes encoding enzymes for anaerobic benzoate degradation during growth on benzene versus growth on acetate, but genes involved in phenol degradation were not upregulated during growth on benzene. A gene for a putative carboxylase that was more highly expressed in benzene- than in benzoate-grown cells was identified. These results suggest that benzene is carboxylated to benzoate and that phenol is not an important intermediate in the benzene metabolism of F. placidus. This is the first demonstration of a microorganism in pure culture that can grow on benzene under strict anaerobic conditions and for which there is strong evidence for degradation of benzene via clearly defined anaerobic metabolic pathways. Thus, F. placidus provides a much-needed pure culture model for further studies on the anaerobic activation of benzene in microorganisms.
[Mh] Termos MeSH primário: Archaeoglobales/metabolismo
Benzeno/metabolismo
[Mh] Termos MeSH secundário: Anaerobiose
Radioisótopos de Carbono/metabolismo
Compostos Férricos/metabolismo
Perfilação da Expressão Gênica
Temperatura Alta
Marcação por Isótopo
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Carbon Radioisotopes); 0 (Ferric Compounds); J64922108F (Benzene)
[Em] Mês de entrada:1112
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:110712
[St] Status:MEDLINE
[do] DOI:10.1128/AEM.05452-11


  9 / 15 MEDLINE  
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[PMID]:19508182
[Au] Autor:Del Vecchio P; Graziano G; Barone G
[Ad] Endereço:Dipartimento di Chimica, Università di Napoli Federico II, Via Cintia, 80126 Napoli, Italy. pompea.delvecchio@unina.it
[Ti] Título:Conformational stability of esterase enzymes from different sources.
[So] Source:Protein Pept Lett;16(10):1201-6, 2009.
[Is] ISSN:1875-5305
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:In the last years we have performed a series of studies to characterize the conformational stability of three esterases from thermophilic and mesophilic sources: Aes esterase from Escherichia coli, EST2 from Alicyclobacillus acidocaldarius and AFEST from Archeoglobus fulgidus. These three esterases belong to the Hormone-sensitive lipase group of the superfamily of carboxylester hydrolases. The conformational stability of the three enzymes against temperature, urea and GuHCl has been determined by means of circular dichroism, fluorescence and differential scanning calorimetry measurements. Analysis of experimental data coupled with available structural information allowed us to suggest that the optimization of charge-charge interactions on the protein surface could one of the mechanisms to increase the thermal stability for the three esterases. This idea has been tested in the case of EST2, which shows a fully reversible thermal unfolding, by producing and studying variant forms of wild type enzyme in which a charged residue has been mutated. In the present article the obtained results are critically recollected in order to provide a clear and unified scenario.
[Mh] Termos MeSH primário: Proteínas Arqueais/química
Proteínas de Bactérias/química
Esterases/química
Conformação Proteica
[Mh] Termos MeSH secundário: Alicyclobacillus/enzimologia
Alicyclobacillus/genética
Proteínas Arqueais/genética
Proteínas Arqueais/metabolismo
Archaeoglobales/enzimologia
Archaeoglobales/genética
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Hidrolases de Éster Carboxílico/química
Hidrolases de Éster Carboxílico/genética
Hidrolases de Éster Carboxílico/metabolismo
Domínio Catalítico
Dicroísmo Circular
Cristalografia por Raios X
Estabilidade Enzimática
Escherichia coli/enzimologia
Escherichia coli/genética
Esterases/genética
Esterases/metabolismo
Guanidina/química
Cinética
Mutação
Dobramento de Proteína
Estrutura Terciária de Proteína
Esterol Esterase/química
Esterol Esterase/genética
Esterol Esterase/metabolismo
Temperatura Ambiente
Ureia/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Archaeal Proteins); 0 (Bacterial Proteins); 8W8T17847W (Urea); EC 3.1.- (Esterases); EC 3.1.1.- (Carboxylic Ester Hydrolases); EC 3.1.1.13 (Sterol Esterase); JU58VJ6Y3B (Guanidine)
[Em] Mês de entrada:1002
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:090611
[St] Status:MEDLINE


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[PMID]:18952801
[Au] Autor:Elliott KT; Zhulin IB; Stuckey JA; DiRita VJ
[Ad] Endereço:Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA.
[Ti] Título:Conserved residues in the HAMP domain define a new family of proposed bipartite energy taxis receptors.
[So] Source:J Bacteriol;191(1):375-87, 2009 Jan.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:HAMP domains, found in many bacterial signal transduction proteins, generally transmit an intramolecular signal between an extracellular sensory domain and an intracellular signaling domain. Studies of HAMP domains in proteins where both the input and output signals occur intracellularly are limited to those of the Aer energy taxis receptor of Escherichia coli, which has both a HAMP domain and a sensory PAS domain. Campylobacter jejuni has an energy taxis system consisting of the domains of Aer divided between two proteins, CetA (HAMP domain containing) and CetB (PAS domain containing). In this study, we found that the CetA HAMP domain differs significantly from that of Aer in the predicted secondary structure. Using similarity searches, we identified 55 pairs of HAMP/PAS proteins encoded by adjacent genes in a diverse group of microorganisms. We propose that these HAMP/PAS pairs form a new family of bipartite energy taxis receptors. Within these proteins, we identified nine residues in the HAMP domain and proximal signaling domain that are highly conserved, at least three of which are required for CetA function. Additionally, we demonstrated that CetA contributes to the invasion of human epithelial cells by C. jejuni, while CetB does not. This finding supports the hypothesis that members of HAMP/PAS pairs possess the capacity to act independently of each other in cellular traits other than energy taxis.
[Mh] Termos MeSH primário: Campylobacter jejuni/genética
Proteínas de Transporte/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas Arqueais/química
Proteínas Arqueais/genética
Proteínas Arqueais/metabolismo
Archaeoglobales/genética
Campylobacter jejuni/metabolismo
Campylobacter jejuni/patogenicidade
Proteínas de Transporte/química
Proteínas de Transporte/metabolismo
Linhagem Celular
Quimiotaxia/genética
Sequência Conservada
Células Epiteliais/microbiologia
Células Epiteliais/fisiologia
Escherichia coli/genética
Escherichia coli/metabolismo
Escherichia coli/patogenicidade
Proteínas de Escherichia coli/química
Proteínas de Escherichia coli/genética
Proteínas de Escherichia coli/metabolismo
Seres Humanos
Dados de Sequência Molecular
Estrutura Secundária de Proteína
Transdução de Sinais/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Archaeal Proteins); 0 (Carrier Proteins); 0 (Escherichia coli Proteins)
[Em] Mês de entrada:0902
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:081028
[St] Status:MEDLINE
[do] DOI:10.1128/JB.00578-08



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