Base de dados : MEDLINE
Pesquisa : B03.440.400.425.377.500 [Categoria DeCS]
Referências encontradas : 421 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 43 ir para página                         

  1 / 421 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29231158
[Au] Autor:Oguntoyinbo FA; Cnockaert M; Cho GS; Kabisch J; Neve H; Bockelmann W; Wenning M; Franz CMAP; Vandamme P
[Ad] Endereço:1​Department of Microbiology and Biotechnology, Max Rubner-Institut, Federal Research Institute for Nutrition and Food, Hermann-Weigmann-Str. 1, 24103 Kiel, Germany.
[Ti] Título:Halomonas nigrificans sp. nov., isolated from cheese.
[So] Source:Int J Syst Evol Microbiol;68(1):371-376, 2018 Jan.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A Gram-stain-negative, rod-shaped Proteobacteria isolate, MBT G8648 , was obtained from an acid curd cheese called Quargel. The isolate was moderately salt tolerant and motile, with numerous peritrichous flagella. The 16S rRNA gene sequence analysis indicated that the strain belongs to the genus Halomonas, with 98.42 % 16S rRNA gene sequence similarity with Halomonas titanicae BH1 as nearest related neighbour. Further comparative sequence analysis of secA and gyrB genes, as well as physiological and biochemical tests, revealed that this bacterium formed a taxon well-separated from its nearest neighbours and other established Halomonas species. Thus, the strain represents a new species, for which the name Halomonas nigrificans sp. nov. is proposed, with strain MBT G8648 (=LMG 29097 =DSM 105749 ) as type strain.
[Mh] Termos MeSH primário: Queijo/microbiologia
Microbiologia de Alimentos
Halomonas/classificação
Filogenia
[Mh] Termos MeSH secundário: Técnicas de Tipagem Bacteriana
Composição de Bases
DNA Bacteriano/genética
Europa (Continente)
Genes Bacterianos
Halomonas/genética
Halomonas/isolamento & purificação
RNA Ribossômico 16S/genética
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180209
[Lr] Data última revisão:
180209
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171213
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002515


  2 / 421 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
[PMID]:27777302
[Au] Autor:Cheng B; Meng Y; Cui Y; Li C; Tao F; Yin H; Yang C; Xu P
[Ad] Endereço:From the State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100 and.
[Ti] Título:Alkaline Response of a Halotolerant Alkaliphilic Halomonas Strain and Functional Diversity of Its Na+(K+)/H+ Antiporters.
[So] Source:J Biol Chem;291(50):26056-26065, 2016 Dec 09.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Halomonas sp. Y2 is a halotolerant alkaliphilic strain from Na -rich pulp mill wastewater with high alkalinity (pH >11.0). Transcriptome analysis of this isolate revealed this strain may use various transport systems for pH homeostasis. In particular, the genes encoding four putative Na /H antiporters were differentially expressed upon acidic or alkaline conditions. Further evidence, from heterologous expression and mutant studies, suggested that Halomonas sp. Y2 employs its Na /H antiporters in a labor division way to deal with saline and alkaline environments. Ha-NhaD2 displayed robust Na (Li ) resistance and high transport activities in Escherichia coli; a ΔHa-nhaD2 mutant exhibited growth inhibition at high Na (Li ) concentrations at pH values of 6.2, 8.0, and 10.0, suggesting its physiological role in osmotic homeostasis. In contrast, Ha-NhaD1 showed much weaker activities in ion exporting and pH homeostasis. Ha-Mrp displayed a combination of properties similar to those of Mrp transporters from some Bacillus alkaliphiles and neutrophiles. This conferred obvious Na (Li , K ) resistance in E. coli-deficient strains, as those ion transport spectra of some neutrophil Mrp antiporters. Conversely, similar to the Bacillus alkaliphiles, Ha-Mrp showed central roles in the pH homeostasis of Halomonas sp. Y2. An Ha-mrp-disrupted mutant was seriously inhibited by high concentrations of Na (Li , K ) but only under alkaline conditions. Ha-NhaP was determined to be a K /H antiporter and shown to confer strong K resistance both at acidic and alkaline stresses.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Halomonas/metabolismo
Antiportadores de Potássio-Hidrogênio/metabolismo
Trocadores de Sódio-Hidrogênio/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Halomonas/química
Halomonas/genética
Concentração de Íons de Hidrogênio
Mutação
Antiportadores de Potássio-Hidrogênio/química
Antiportadores de Potássio-Hidrogênio/genética
Trocadores de Sódio-Hidrogênio/química
Trocadores de Sódio-Hidrogênio/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Potassium-Hydrogen Antiporters); 0 (Sodium-Hydrogen Exchangers)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171209
[Lr] Data última revisão:
171209
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161026
[St] Status:MEDLINE


  3 / 421 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28803103
[Au] Autor:Chen X; Yin J; Ye J; Zhang H; Che X; Ma Y; Li M; Wu LP; Chen GQ
[Ad] Endereço:School of Life Sciences, Tsinghua University, Beijing 100084, China.
[Ti] Título:Engineering Halomonas bluephagenesis TD01 for non-sterile production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate).
[So] Source:Bioresour Technol;244(Pt 1):534-541, 2017 Nov.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Poly(3-hydroxybutyrate-co-4-hydroxybutyrate), short as P(3HB-co-4HB), was successfully produced by engineered Halomonas bluephagenesis TD01 grown in glucose and γ-butyrolactone under open non-sterile conditions. Gene orfZ encoding 4HB-CoA transferase of Clostridium kluyveri was integrated into the genome to achieve P(3HB-co-4HB) accumulation comparable to that of strains encoding orfZ on plasmids. Fed-batch cultivations conducted in 1-L and 7-L fermentors, respectively, resulted in over 70g/L cell dry weight (CDW) containing 63% P(3HB-co-12mol% 4HB) after 48h under non-sterile conditions. The processes were further scaled up in a 1000-L pilot fermentor to reach 83g/L CDW containing 61% P(3HB-co-16mol% 4HB) in 48h, with a productivity of 1.04g/L/h, again, under non-sterile conditions. The elastic P(3HB-co-16mol% 4HB) shows an elongation at break of 1022±43%. Results demonstrate that the engineered Halomonas bluephagenesis TD01 is a suitable industrial strain for large scale production under open non-sterile conditions.
[Mh] Termos MeSH primário: Halomonas
Hidroxibutiratos
Poliésteres
[Mh] Termos MeSH secundário: Ácido 3-Hidroxibutírico
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hydroxybutyrates); 0 (Polyesters); 117068-64-1 (poly(3-hydroxybutyrate-co-4-hydroxybutyrate)); TZP1275679 (3-Hydroxybutyric Acid)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171106
[Lr] Data última revisão:
171106
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170814
[St] Status:MEDLINE


  4 / 421 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28559301
[Au] Autor:Meng Y; Yang Z; Cheng B; Nie X; Li S; Yin H; Xu P; Yang C
[Ad] Endereço:State Key Laboratory of Microbial Technology, Shandong University, Jinan, People's Republic of China.
[Ti] Título:Functional Interaction between the N and C Termini of NhaD Antiporters from Halomonas sp. Strain Y2.
[So] Source:J Bacteriol;199(16), 2017 Aug 15.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Two NhaD-type antiporters, NhaD1 and NhaD2, from the halotolerant and alkaliphilic sp. strain Y2, exhibit different physiological functions in regard to Na and Li resistance, although they share high sequence identity. In the present study, the truncation of an additional 4 C-terminal residues from NhaD2 or an exchange of 39 N-terminal residues between these proteins resulted in the complete loss of antiporter activity. Interestingly, combining 39 N-terminal residues and 7 C-terminal residues of NhaD2 (N39D2-C7) partially recovered the activity for Na and Li expulsion, as well as complementary growth following exposure to 300 mM Na and 100 mM Li stress. The recovered activity of chimera N39D2-C7 indicated that the N and C termini are structurally dependent on each other and function synergistically. Furthermore, fluorescence resonance energy transfer (FRET) analysis suggested that the N and C termini are relatively close in proximity which may account for their synergistic function in ion translocation. In the N-terminal region of N39D2-C7, the replacement of Glu with Pro abolished the recovered complementary and transport activities. In addition, this amino acid substitution in NhaD2 resulted in a drastically decreased complementation ability in KNabc (level identical to that of NhaD1), as well as decreased activity and an altered pH profile. Limited information on NhaD antiporters supports speculation that these antiporters are important for resistance to high salinity and alkalinity. Moreover, only a few functional residues have been identified in NhaD antiporters, and there is limited literature on the molecular mechanisms of NhaD antiporter activity. The altered antiporter abilities of chimeras and mutants in this study implicate the functions of the N and C termini, especially Glu , in pH regulation and ion translocation, and, most importantly, the essential roles of this negatively charged residue in maintaining the physiological function of NhaD2. These findings further our understanding of the molecular mechanism of NhaD antiporters for ion transport.
[Mh] Termos MeSH primário: Antiporters/metabolismo
Halomonas/enzimologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Antiporters/química
Antiporters/genética
Análise Mutacional de DNA
Escherichia coli/genética
Teste de Complementação Genética
Halomonas/genética
Halomonas/metabolismo
Modelos Moleculares
Ligação Proteica
Conformação Proteica
Recombinação Genética
Deleção de Sequência
Homologia de Sequência de Aminoácidos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antiporters)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170809
[Lr] Data última revisão:
170809
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170601
[St] Status:MEDLINE


  5 / 421 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28531862
[Au] Autor:Gutiérrez-Arnillas E; Arellano M; Deive FJ; Rodríguez A; Sanromán MÁ
[Ad] Endereço:Department of Chemical Engineering, University of Vigo, 36310 Vigo, Spain.
[Ti] Título:Unravelling the suitability of biological induction for halophilic lipase production by Halomonas sp. LM1C cultures.
[So] Source:Bioresour Technol;239:368-377, 2017 Sep.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In this study, the viability of using biological induction as an alternative to the conventional chemical induction in lipase production by a novel halophilic microorganism, Halomonas sp. LM1C, has been demonstrated. Thus, a 9-times increase of lipase activity (3000U/L) was recorded when Staphylococcus equorum sp. AMC7 was present in the medium, which is competitive with the results obtained when Triton X-100 was added as chemical inducer. The GC-MS data allowed concluding the true nature of the biological inducer effect, as the existence of high percentages of isomeric forms of pentadecanoic acid were detected. The suitability of the proposed strategy was validated by operating at bench scale bioreactor, and the influence of bioreactor configuration on the biomass and lipolytic activity levels was studied. All the data were fitted to logistic and Luedeking & Piret models to characterize the bioprocess kinetics, concluding the growth-associated character of the produced lipolytic enzymes.
[Mh] Termos MeSH primário: Halomonas
Lipase
[Mh] Termos MeSH secundário: Reatores Biológicos
Cinética
Octoxinol
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9002-93-1 (Octoxynol); EC 3.1.1.3 (Lipase)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171106
[Lr] Data última revisão:
171106
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170523
[St] Status:MEDLINE


  6 / 421 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28381263
[Au] Autor:Tao W; Lv L; Chen GQ
[Ad] Endereço:School of Life Sciences, Tsinghua University, Beijing, 100084, China.
[Ti] Título:Engineering Halomonas species TD01 for enhanced polyhydroxyalkanoates synthesis via CRISPRi.
[So] Source:Microb Cell Fact;16(1):48, 2017 Apr 06.
[Is] ISSN:1475-2859
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Clustered regularly interspaced short palindromic repeats interference (CRISPRi) has provided an efficient approach for targeted gene inhibition. A non-model microorganism Halomonas species TD01 has been developed as a promising industrial producer of polyhydroxyalkanoates (PHA), a family of biodegradable polyesters accumulated by bacteria as a carbon and energy reserve compound. A controllable gene repression system, such as CRISPRi, is needed for Halomonas sp. TD01 to regulate its gene expression levels. RESULTS: For the first time CRISPRi was successfully used in Halomonas sp. TD01 to repress expression of ftsZ gene encoding bacterial fission ring formation protein, leading to an elongated cell morphology with typical filamentous shape similar to phenomenon observed with Escherichia coli. CRISPRi was employed to regulate expressions of prpC gene encoding 2-methylcitrate synthase for regulating 3-hydroxyvalerate monomer ratio in PHBV copolymers of 3-hydroxybutyrate (HB) and 3-hydroxyvalerate (HV). Percentages of HV in PHBV copolymers were controllable ranging from less than 1 to 13%. Furthermore, repressions on gltA gene encoding citrate synthase channeled more acetyl-CoA from the tricarboxylic acid (TCA) cycle to poly(3-hydroxybutyrate) (PHB) synthesis. The PHB accumulation by Halomonas sp. TD01 with its gltA gene repressed in various intensities via CRISPRi was increased by approximately 8% compared with the wild type control containing the CRISPRi vector without target. CONCLUSIONS: It has now been confirmed that the CRISPRi system can be applied to Halomonas sp. TD01, a promising industrial strain for production of various PHA and chemicals under open and continuous fermentation process conditions. In details, the CRISPRi system was successfully designed in this study to target genes of ftsZ, prpC and gltA, achieving longer cell sizes, channeling more substrates to PHBV and PHB synthesis, respectively. CRISPRi can be expected to use for more metabolic engineering applications in non-model organisms.
[Mh] Termos MeSH primário: Sistemas CRISPR-Cas
Halomonas/genética
Engenharia Metabólica/métodos
Poli-Hidroxialcanoatos/biossíntese
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Citrato (si)-Sintase/genética
Proteínas do Citoesqueleto/genética
Inativação Gênica
Halomonas/metabolismo
Hidroxibutiratos/metabolismo
Oxo-Ácido-Liases/genética
Poliésteres/metabolismo
Poli-Hidroxialcanoatos/metabolismo
Biologia Sintética/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Cytoskeletal Proteins); 0 (FtsZ protein, Bacteria); 0 (Hydroxybutyrates); 0 (Polyesters); 0 (Polyhydroxyalkanoates); 0 (poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate)); 26063-00-3 (poly-beta-hydroxybutyrate); EC 2.3.3.1 (Citrate (si)-Synthase); EC 2.3.3.5 (2-methylcitrate synthase); EC 4.1.3.- (Oxo-Acid-Lyases)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170424
[Lr] Data última revisão:
170424
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170407
[St] Status:MEDLINE
[do] DOI:10.1186/s12934-017-0655-3


  7 / 421 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28131879
[Au] Autor:Sakurai N; Kataoka K; Sugaya N; Shimodaira T; Iwamoto M; Shoda M; Horiuchi H; Kiyono M; Ohta Y; Triwiyono B; Seo D; Sakurai T
[Ad] Endereço:Division of Biological Science, Graduate School of Natural Sciences, Nagoya City University, Yamanohata 1, Mizuho, Nagoya 467-8501, Japan. Electronic address: sakurai@nsc.nagoya-cu.ac.jp.
[Ti] Título:Heterologous expression of Halomonas halodenitrificans nitric oxide reductase and its N-terminally truncated NorC subunit in Escherichia coli.
[So] Source:J Inorg Biochem;169:61-67, 2017 Apr.
[Is] ISSN:1873-3344
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Halomonas halodenitrificans nitric oxide reductase (NOR) is the membrane-bound heterodimer complex of NorC, which contains a low-spin heme c center, and NorB, which contains a low-spin heme b center, a high-spin heme b center, and a non-heme Fe center. The soluble domain of NorC, NorC* (ΔMet1-Val37) was heterologously expressed in Escherichia coli using expression plasmids harboring the truncated norC gene deleted of its 84 5'-terminal nucleotides. Analogous scission of the N-terminal helix as the membrane anchor took place when the whole norC gene was used. NorC* exhibited spectra typical of a low-spin heme c. In addition, NorC* functioned as the acceptor of an electron from a cytochrome c isolated from the periplasm of H. halodenitrificans and small reducing reagents. The redox potential of NorC* shifted ca. 40mV in the negative direction from that of NorC. Unlike NorC, recombinant NorB was not heterologously expressed. However, recombinant NOR (rNOR) could be expressed in E. coli by using a plasmid harboring all genes in the nor operon, norCBQDX, from which the three hairpin loops (mRNA) were deleted, and by using the ccm genes for the maturation of C-type heme. rNOR exhibited the same spectroscopic properties and reactivity to NO and O as NOR, although its enzymatic activity toward NO was considerably decreased. These results on the expression of rNOR and NorC* will allow us to develop more profound studies on the properties of the four Fe centers and the reaction mechanism of NOR from this halophilic denitrifying bacterium.
[Mh] Termos MeSH primário: Escherichia coli/enzimologia
Halomonas/enzimologia
Oxirredutases/metabolismo
Subunidades Proteicas/metabolismo
[Mh] Termos MeSH secundário: Escherichia coli/genética
Escherichia coli/metabolismo
Óperon/genética
Oxirredutases/química
Oxirredutases/genética
Plasmídeos/genética
Estrutura Secundária de Proteína
Subunidades Proteicas/química
Subunidades Proteicas/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Protein Subunits); EC 1.- (Oxidoreductases); EC 1.7.2.5 (nitric-oxide reductase)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170519
[Lr] Data última revisão:
170519
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170130
[St] Status:MEDLINE


  8 / 421 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28123098
[Au] Autor:Harrison JP; Angel R; Cockell CS
[Ad] Endereço:UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, UK jesse.p.harrison@gmail.com.
[Ti] Título:Astrobiology as a framework for investigating antibiotic susceptibility: a study of Halomonas hydrothermalis.
[So] Source:J R Soc Interface;14(126), 2017 Jan.
[Is] ISSN:1742-5662
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Physical and chemical boundaries for microbial multiplication on Earth are strongly influenced by interactions between environmental extremes. However, little is known about how interactions between multiple stress parameters affect the sensitivity of microorganisms to antibiotics. Here, we assessed how 12 distinct permutations of salinity, availability of an essential nutrient (iron) and atmospheric composition (aerobic or microaerobic) affect the susceptibility of a polyextremotolerant bacterium, Halomonas hydrothermalis, to ampicillin, kanamycin and ofloxacin. While salinity had a significant impact on sensitivity to all three antibiotics (as shown by turbidimetric analyses), the nature of this impact was modified by iron availability and the ambient gas composition, with differing effects observed for each compound. These two parameters were found to be of particular importance when considered in combination and, in the case of ampicillin, had a stronger combined influence on antibiotic tolerance than salinity. Our data show how investigating microbial responses to multiple extremes, which are more representative of natural habitats than single extremes, can improve our understanding of the effects of antimicrobial compounds and suggest how studies of habitability, motivated by the desire to map the limits of life, can be used to systematically assess the effectiveness of antibiotics.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Farmacorresistência Bacteriana/fisiologia
Ecossistema
Halomonas/fisiologia
Salinidade
[Mh] Termos MeSH secundário: Farmacorresistência Bacteriana/efeitos dos fármacos
Exobiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170127
[St] Status:MEDLINE


  9 / 421 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28103254
[Au] Autor:Mardo K; Visnapuu T; Vija H; Aasamets A; Viigand K; Alamäe T
[Ad] Endereço:Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia.
[Ti] Título:A Highly Active Endo-Levanase BT1760 of a Dominant Mammalian Gut Commensal Bacteroides thetaiotaomicron Cleaves Not Only Various Bacterial Levans, but Also Levan of Timothy Grass.
[So] Source:PLoS One;12(1):e0169989, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacteroides thetaiotaomicron, an abundant commensal of the human gut, degrades numerous complex carbohydrates. Recently, it was reported to grow on a ß-2,6-linked polyfructan levan produced by Zymomonas mobilis degrading the polymer into fructooligosaccharides (FOS) with a cell surface bound endo-levanase BT1760. The FOS are consumed by B. thetaiotaomicron, but also by other gut bacteria, including health-promoting bifidobacteria and lactobacilli. Here we characterize biochemical properties of BT1760, including the activity of BT1760 on six bacterial levans synthesized by the levansucrase Lsc3 of Pseudomonas syringae pv. tomato, its mutant Asp300Asn, levansucrases of Zymomonas mobilis, Erwinia herbicola, Halomonas smyrnensis as well as on levan isolated from timothy grass. For the first time a plant levan is shown as a perfect substrate for an endo-fructanase of a human gut bacterium. BT1760 degraded levans to FOS with degree of polymerization from 2 to 13. At optimal reaction conditions up to 1 g of FOS were produced per 1 mg of BT1760 protein. Low molecular weight (<60 kDa) levans, including timothy grass levan and levan synthesized from sucrose by the Lsc3Asp300Asn, were degraded most rapidly whilst levan produced by Lsc3 from raffinose least rapidly. BT1760 catalyzed finely at human body temperature (37°C) and in moderately acidic environment (pH 5-6) that is typical for the gut lumen. According to differential scanning fluorimetry, the Tm of the endo-levanase was 51.5°C. All tested levans were sufficiently stable in acidic conditions (pH 2.0) simulating the gastric environment. Therefore, levans of both bacterial and plant origin may serve as a prebiotic fiber for B. thetaiotaomicron and contribute to short-chain fatty acids synthesis by gut microbiota. In the genome of Bacteroides xylanisolvens of human origin a putative levan degradation locus was disclosed.
[Mh] Termos MeSH primário: Bacteroides thetaiotaomicron/enzimologia
Frutanos/metabolismo
Glicosídeo Hidrolases/metabolismo
Phleum/metabolismo
[Mh] Termos MeSH secundário: Erwinia/enzimologia
Frutanos/genética
Frutanos/isolamento & purificação
Halomonas/enzimologia
Hexosiltransferases/metabolismo
Seres Humanos
Hidrólise
Intestinos/microbiologia
Peso Molecular
Oligossacarídeos/metabolismo
Pseudomonas syringae/enzimologia
Homologia de Sequência
Especificidade por Substrato
Zymomonas/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fructans); 0 (Oligosaccharides); 0 (fructooligosaccharide); EC 2.4.1.- (Hexosyltransferases); EC 2.4.1.10 (levansucrase); EC 3.2.1.- (Glycoside Hydrolases); EC 3.2.1.65 (levanase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170821
[Lr] Data última revisão:
170821
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170120
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0169989


  10 / 421 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28081159
[Au] Autor:Kindzierski V; Raschke S; Knabe N; Siedler F; Scheffer B; Pflüger-Grau K; Pfeiffer F; Oesterhelt D; Marin-Sanguino A; Kunte HJ
[Ad] Endereço:Faculty of Mechanical Engineering, Specialty Division for Systems Biotechnology, Technische Universität München, München, Germany.
[Ti] Título:Osmoregulation in the Halophilic Bacterium Halomonas elongata: A Case Study for Integrative Systems Biology.
[So] Source:PLoS One;12(1):e0168818, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Halophilic bacteria use a variety of osmoregulatory methods, such as the accumulation of one or more compatible solutes. The wide diversity of compounds that can act as compatible solute complicates the task of understanding the different strategies that halophilic bacteria use to cope with salt. This is specially challenging when attempting to go beyond the pathway that produces a certain compatible solute towards an understanding of how the metabolic network as a whole addresses the problem. Metabolic reconstruction based on genomic data together with Flux Balance Analysis (FBA) is a promising tool to gain insight into this problem. However, as more of these reconstructions become available, it becomes clear that processes predicted by genome annotation may not reflect the processes that are active in vivo. As a case in point, E. coli is unable to grow aerobically on citrate in spite of having all the necessary genes to do it. It has also been shown that the realization of this genetic potential into an actual capability to metabolize citrate is an extremely unlikely event under normal evolutionary conditions. Moreover, many marine bacteria seem to have the same pathways to metabolize glucose but each species uses a different one. In this work, a metabolic network inferred from genomic annotation of the halophilic bacterium Halomonas elongata and proteomic profiling experiments are used as a starting point to motivate targeted experiments in order to find out some of the defining features of the osmoregulatory strategies of this bacterium. This new information is then used to refine the network in order to describe the actual capabilities of H. elongata, rather than its genetic potential.
[Mh] Termos MeSH primário: Proteínas de Bactérias/biossíntese
Regulação Bacteriana da Expressão Gênica/fisiologia
Halomonas/metabolismo
Osmorregulação/fisiologia
Proteoma/biossíntese
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Perfilação da Expressão Gênica
Halomonas/genética
Proteoma/genética
Biologia de Sistemas
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Proteome)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170802
[Lr] Data última revisão:
170802
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170113
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0168818



página 1 de 43 ir para página                         
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde