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  1 / 2607 MEDLINE  
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[PMID]:29184998
[Au] Autor:Cürten C; Anders N; Juchem N; Ihling N; Volkenborn K; Knapp A; Jaeger KE; Büchs J; Spiess AC
[Ad] Endereço:Aachener Verfahrenstechnik-Enzyme Process Technology, RWTH Aachen University, Worringer Weg 1, 52074, Aachen, Germany.
[Ti] Título:Fast automated online xylanase activity assay using HPAEC-PAD.
[So] Source:Anal Bioanal Chem;410(1):57-69, 2018 Jan.
[Is] ISSN:1618-2650
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:In contrast to biochemical reactions, which are often carried out under automatic control and maintained overnight, the automation of chemical analysis is usually neglected. Samples are either analyzed in a rudimentary fashion using in situ techniques, or aliquots are withdrawn and stored to facilitate more precise offline measurements, which can result in sampling and storage errors. Therefore, in this study, we implemented automated reaction control, sampling, and analysis. As an example, the activities of xylanases on xylotetraose and soluble xylan were examined using high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The reaction was performed in HPLC vials inside a temperature-controlled Dionex™ AS-AP autosampler. It was started automatically when the autosampler pipetted substrate and enzyme solution into the reaction vial. Afterwards, samples from the reaction vial were injected repeatedly for 60 min onto a CarboPac™ PA100 column for analysis. Due to the rapidity of the reaction, the analytical method and the gradient elution of 200 mM sodium hydroxide solution and 100 mM sodium hydroxide with 500 mM sodium acetate were adapted to allow for an overall separation time of 13 min and a detection limit of 0.35-1.83 mg/L (depending on the xylooligomer). This analytical method was applied to measure the soluble short-chain products (xylose, xylobiose, xylotriose, xylotetraose, xylopentaose, and longer xylooligomers) that arise during enzymatic hydrolysis. Based on that, the activities of three endoxylanases (EX) were determined as 294 U/mg for EX from Aspergillus niger, 1.69 U/mg for EX from Bacillus stearothermophilus, and 0.36 U/mg for EX from Bacillus subtilis. Graphical abstract Xylanase activity assay automation.
[Mh] Termos MeSH primário: Aspergillus niger/enzimologia
Cromatografia por Troca Iônica/métodos
Endo-1,4-beta-Xilanases/metabolismo
Ensaios Enzimáticos/métodos
Geobacillus stearothermophilus/enzimologia
[Mh] Termos MeSH secundário: Cromatografia Líquida de Alta Pressão/métodos
Cromatografia por Troca Iônica/economia
Endo-1,4-beta-Xilanases/análise
Ensaios Enzimáticos/economia
Hidrólise
Limite de Detecção
Fatores de Tempo
Xilanos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Xylans); EC 3.2.1.8 (Endo-1,4-beta Xylanases)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171130
[St] Status:MEDLINE
[do] DOI:10.1007/s00216-017-0712-0


  2 / 2607 MEDLINE  
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[PMID]:29250543
[Au] Autor:Li Z; Su L; Duan X; Wu D; Wu J
[Ad] Endereço:State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China.
[Ti] Título:Efficient Expression of Maltohexaose-Forming -Amylase from in SP3 and Its Use in Maltose Production.
[So] Source:Biomed Res Int;2017:5479762, 2017.
[Is] ISSN:2314-6141
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The maltohexaose-forming, Ca -independent -amylase gene from (AmyMH) was efficiently expressed in SP3. To improve the production of AmyMH in SP3, the temperature and initial pH of culture medium were optimized. In addition, single-factor and response surface methodologies were pursued to optimize culture medium. Addition of proline to the culture medium significantly improved the production of recombinant -amylase in SP3. This improvement may result from improved cellular integrity of recombinant SP3 in existence of proline. Culture medium optimization resulted in an 8-fold improvement in -amylase yield, which reached 1.72 × 10 U·mL . The recombinant -amylase was applied to the production of maltose on a laboratory scale. A maltose content of 90.72%, which could be classified as an extremely high maltose syrup, could be achieved using 15% (m/v) corn starch as the substrate. This study demonstrated that the SP3 expression system was able to produce substantial quantities of recombinant -amylase that has potential application in the starch industry.
[Mh] Termos MeSH primário: Brevibacillus/metabolismo
Geobacillus stearothermophilus/enzimologia
Maltose/metabolismo
Oligossacarídeos/metabolismo
alfa-Amilases/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Reatores Biológicos
Brevibacillus/genética
Meios de Cultura
Fermentação
Geobacillus stearothermophilus/genética
Glucose/metabolismo
Maltose/análise
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
alfa-Amilases/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Culture Media); 0 (Oligosaccharides); 0 (Recombinant Proteins); 34620-77-4 (maltohexaose); 69-79-4 (Maltose); EC 3.2.1.1 (alpha-Amylases); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.1155/2017/5479762


  3 / 2607 MEDLINE  
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[PMID]:27778473
[Au] Autor:Gihaz S; Weiser D; Dror A; Sátorhelyi P; Jerabek-Willemsen M; Poppe L; Fishman A
[Ad] Endereço:Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, 3200003, Israel.
[Ti] Título:Creating an Efficient Methanol-Stable Biocatalyst by Protein and Immobilization Engineering Steps towards Efficient Biosynthesis of Biodiesel.
[So] Source:ChemSusChem;9(22):3161-3170, 2016 11 23.
[Is] ISSN:1864-564X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Two ternary sol-gel matrices, an octyltriethoxysilane-based aliphatic matrix and a phenyltriethoxysilane (PTEOS)-based aromatic matrix, were used to immobilize a methanol-stable variant of lipase from Geobacillus stearothermophilus T6 for the synthesis of biodiesel from waste oil. Superior thermal stability of the mutant versus the wildtype in methanol was confirmed by intrinsic protein fluorescence measurements. The influence of skim milk and soluble E. coli lysate proteins as bulking and stabilizing agents in conjunction with sol-gel entrapment were investigated. E. coli lysate proteins were better stabilizing agents of the purified lipase mutant than skim milk, as evidenced by reverse engineering of the aromatic-based system. This was also shown for commercial Candida antarctica lipase B (CaLB) and Thermomyces lanuginosus lipase (TLL). Uniform, dense, and nonaggregated particles imaged by scanning electron microscopy and a small particle size of 13 µm pertaining to the system comprising PTEOS and E. coli lysate proteins correlated well with high esterification activity. Combining protein and immobilization engineering resulted in a durable biocatalyst with efficient recycling ability and high biodiesel conversion rates.
[Mh] Termos MeSH primário: Biocatálise
Biocombustíveis
Enzimas Imobilizadas/química
Enzimas Imobilizadas/metabolismo
Lipase/química
Lipase/metabolismo
Metanol/farmacologia
[Mh] Termos MeSH secundário: Animais
Estabilidade Enzimática/efeitos dos fármacos
Enzimas Imobilizadas/genética
Proteínas de Escherichia coli/química
Geobacillus stearothermophilus/enzimologia
Hidrólise
Lipase/genética
Leite/química
Modelos Moleculares
Conformação Proteica
Engenharia de Proteínas
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Biofuels); 0 (Enzymes, Immobilized); 0 (Escherichia coli Proteins); EC 3.1.1.3 (Lipase); Y4S76JWI15 (Methanol)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:180117
[Lr] Data última revisão:
180117
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161026
[St] Status:MEDLINE
[do] DOI:10.1002/cssc.201601158


  4 / 2607 MEDLINE  
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[PMID]:28934494
[Au] Autor:Oscorbin IP; Belousova EA; Boyarskikh UA; Zakabunin AI; Khrapov EA; Filipenko ML
[Ad] Endereço:Laboratory of Pharmacogenomics, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Lavrentiev Avenue 8, Novosibirsk 630090, Russian Federation.
[Ti] Título:Derivatives of Bst-like Gss-polymerase with improved processivity and inhibitor tolerance.
[So] Source:Nucleic Acids Res;45(16):9595-9610, 2017 Sep 19.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:At the moment, one of the actual trends in medical diagnostics is a development of methods for practical applications such as point-of-care testing, POCT or research tools, for example, whole genome amplification, WGA. All the techniques are based on using of specific DNA polymerases having strand displacement activity, high synthetic processivity, fidelity and, most significantly, tolerance to contaminants, appearing from analysed biological samples or collected under purification procedures. Here, we have designed a set of fusion enzymes based on catalytic domain of DNA polymerase I from Geobacillus sp. 777 with DNA-binding domain of DNA ligase Pyrococcus abyssi and Sto7d protein from Sulfolobus tokodaii, analogue of Sso7d. Designed chimeric DNA polymerases DBD-Gss, Sto-Gss and Gss-Sto exhibited the same level of thermal stability, thermal transferase activity and fidelity as native Gss; however, the processivity was increased up to 3-fold, leading to about 4-fold of DNA product in WGA which is much more exiting. The attachment of DNA-binding proteins enhanced the inhibitor tolerance of chimeric polymerases in loop-mediated isothermal amplification to several of the most common DNA sample contaminants-urea and whole blood, heparin, ethylenediaminetetraacetic acid, NaCl, ethanol. Therefore, chimeric Bst-like Gss-polymerase will be promising tool for both WGA and POCT due to increased processivity and inhibitor tolerance.
[Mh] Termos MeSH primário: DNA Polimerase I/metabolismo
Geobacillus/enzimologia
Engenharia de Proteínas/métodos
Proteínas Recombinantes de Fusão/genética
[Mh] Termos MeSH secundário: Domínio Catalítico
Clonagem Molecular
DNA/metabolismo
DNA Polimerase I/antagonistas & inibidores
DNA Polimerase I/genética
Inibidores Enzimáticos/farmacologia
Genoma Humano
Geobacillus/genética
Geobacillus stearothermophilus/enzimologia
Geobacillus stearothermophilus/genética
Seres Humanos
Técnicas de Amplificação de Ácido Nucleico/métodos
Estabilidade Proteica
Pyrococcus abyssi/genética
Proteínas Recombinantes de Fusão/metabolismo
Sulfolobus/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Enzyme Inhibitors); 0 (Recombinant Fusion Proteins); 9007-49-2 (DNA); EC 2.7.7.- (DNA Polymerase I)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170922
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx645


  5 / 2607 MEDLINE  
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[PMID]:28898405
[Au] Autor:Pei H; Han S; Yang S; Lei Z; Zheng J; Jia Z
[Ad] Endereço:College of Chemistry, Beijing Normal University, China.
[Ti] Título:Phosphorylation of bacterial L9 and its functional implication in response to starvation stress.
[So] Source:FEBS Lett;591(20):3421-3430, 2017 Oct.
[Is] ISSN:1873-3468
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The bacterial L9 (bL9) protein expressed and purified from Escherichia coli is stably phosphorylated. We mapped seven Ser/Thr phosphorylation sites, all of which but one are located at the carboxyl-terminal domain (CTD). When a histidine tag is fused to the C-terminus, bL9 is no longer phosphorylated. Phosphorylation of bL9 causes complete disordering of its CTD and helps cell survival under nutrient-limiting conditions. Previous structural studies of the ribosome have shown that bL9 exhibits two distinct conformations, one of which competes with binding of RelA to the 30s rRNA and prevents RelA activation. Taken together, we suggest that the flexibility of the bL9 CTD enabled by phosphorylation would remove the steric hindrance, serving as a previously unknown mechanism to regulate RelA function and help cell survival under starvation stress.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Escherichia coli/metabolismo
Geobacillus stearothermophilus/química
Proteínas Ribossômicas/química
Ribossomos/química
Estresse Fisiológico
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Sítios de Ligação
Clonagem Molecular
Cristalografia por Raios X
Meios de Cultura/farmacologia
Escherichia coli/efeitos dos fármacos
Escherichia coli/genética
Expressão Gênica
Geobacillus stearothermophilus/metabolismo
Modelos Moleculares
Mutação
Fosforilação
Ligação Proteica
Conformação Proteica em alfa-Hélice
Conformação Proteica em Folha beta
Domínios e Motivos de Interação entre Proteínas
Estrutura Terciária de Proteína
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Proteínas Ribossômicas/genética
Proteínas Ribossômicas/metabolismo
Ribossomos/genética
Ribossomos/metabolismo
Alinhamento de Sequência
Homologia de Sequência de Aminoácidos
Especificidade por Substrato
[Pt] Tipo de publicação:LETTER
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Culture Media); 0 (Recombinant Proteins); 0 (Ribosomal Proteins); 0 (ribosomal protein L9)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170913
[St] Status:MEDLINE
[do] DOI:10.1002/1873-3468.12840


  6 / 2607 MEDLINE  
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[PMID]:28808061
[Au] Autor:Li YC; Naveen V; Lin MG; Hsiao CD
[Ad] Endereço:From the Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan and.
[Ti] Título:Structural analyses of the bacterial primosomal protein DnaB reveal that it is a tetramer and forms a complex with a primosomal re-initiation protein.
[So] Source:J Biol Chem;292(38):15744-15757, 2017 Sep 22.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The DnaB primosomal protein from Gram-positive bacteria plays a key role in DNA replication and restart as a loader protein for the recruitment of replisome cascade proteins. Previous investigations have established that DnaB is composed of an N-terminal domain, a middle domain, and a C-terminal domain. However, structural evidence for how DnaB functions at the atomic level is lacking. Here, we report the crystal structure of DnaB, encompassing the N-terminal and middle domains (residues 1-300), from ( DnaB ) at 2.8 Å resolution. Our structure revealed that DnaB forms a tetramer with two basket-like architectures, a finding consistent with those from solution studies using analytical ultracentrifugation. Furthermore, our results from both GST pulldown assays and analytical ultracentrifugation show that DnaB is sufficient to form a complex with PriA, the primosomal reinitiation protein. Moreover, with the aid of small angle X-ray scattering experiments, we also determined the structural envelope of full-length DnaB ( DnaB ) in solution. These small angle X-ray scattering studies indicated that DnaB has an elongated conformation and that the protruding density envelopes originating from DnaB could completely accommodate the DnaB C-terminal domain (residues 301-461). Taken together with biochemical assays, our results suggest that DnaB uses different domains to distinguish the PriA interaction and single-stranded DNA binding. These findings can further extend our understanding of primosomal assembly in replication restart.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
DnaB Helicases/química
DnaB Helicases/metabolismo
Multimerização Proteica
[Mh] Termos MeSH secundário: DNA de Cadeia Simples/metabolismo
Geobacillus stearothermophilus/enzimologia
Modelos Moleculares
Ligação Proteica
Domínios Proteicos
Estrutura Quaternária de Proteína
Alinhamento de Sequência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (DNA, Single-Stranded); EC 3.6.4.12 (DnaB Helicases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171009
[Lr] Data última revisão:
171009
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170816
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.792002


  7 / 2607 MEDLINE  
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[PMID]:28777085
[Au] Autor:Naitow H; Matsuura Y; Tono K; Joti Y; Kameshima T; Hatsui T; Yabashi M; Tanaka R; Tanaka T; Sugahara M; Kobayashi J; Nango E; Iwata S; Kunishima N
[Ad] Endereço:Bio-Specimen Platform Group, RIKEN SPring-8 Center, Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.
[Ti] Título:Protein-ligand complex structure from serial femtosecond crystallography using soaked thermolysin microcrystals and comparison with structures from synchrotron radiation.
[So] Source:Acta Crystallogr D Struct Biol;73(Pt 8):702-709, 2017 Aug 01.
[Is] ISSN:2059-7983
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Serial femtosecond crystallography (SFX) with an X-ray free-electron laser is used for the structural determination of proteins from a large number of microcrystals at room temperature. To examine the feasibility of pharmaceutical applications of SFX, a ligand-soaking experiment using thermolysin microcrystals has been performed using SFX. The results were compared with those from a conventional experiment with synchrotron radiation (SR) at 100 K. A protein-ligand complex structure was successfully obtained from an SFX experiment using microcrystals soaked with a small-molecule ligand; both oil-based and water-based crystal carriers gave essentially the same results. In a comparison of the SFX and SR structures, clear differences were observed in the unit-cell parameters, in the alternate conformation of side chains, in the degree of water coordination and in the ligand-binding mode.
[Mh] Termos MeSH primário: Cristalografia/métodos
Geobacillus stearothermophilus/química
Geobacillus stearothermophilus/enzimologia
Termolisina/química
[Mh] Termos MeSH secundário: Cristalização/métodos
Cristalografia por Raios X/métodos
Desenho de Drogas
Geobacillus stearothermophilus/metabolismo
Ligantes
Modelos Moleculares
Conformação Proteica
Síncrotrons
Termolisina/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ligands); EC 3.4.24.27 (Thermolysin)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170805
[St] Status:MEDLINE
[do] DOI:10.1107/S2059798317008919


  8 / 2607 MEDLINE  
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[PMID]:28648296
[Au] Autor:Kakagianni M; Aguirre JS; Lianou A; Koutsoumanis KP
[Ad] Endereço:Laboratory of Food Microbiology and Hygiene, Department of Food Science and Technology, School of Agriculture, Faculty of Agriculture, Forestry and Natural Environment, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.
[Ti] Título:Effect of storage temperature on the lag time of Geobacillus stearothermophilus individual spores.
[So] Source:Food Microbiol;67:76-84, 2017 Oct.
[Is] ISSN:1095-9998
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The lag times (λ) of Geobacillus stearothermophilus single spores were studied at different storage temperatures ranging from 45 to 59 °C using the Bioscreen C method. A significant variability of λ was observed among individual spores at all temperatures tested. The storage temperature affected both the position and the spread of the λ distributions. The minimum mean value of λ (i.e. 10.87 h) was observed at 55 °C, while moving away from this temperature resulted in an increase for both the mean and standard deviation of λ. A Cardinal Model with Inflection (CMI) was fitted to the reverse mean λ, and the estimated values for the cardinal parameters T , T , T and the optimum mean λ of G. stearothermophilus were found to be 38.1, 64.2, 53.6 °C and 10.3 h, respectively. To interpret the observations, a probabilistic growth model for G. stearothermophilus individual spores, taking into account λ variability, was developed. The model describes the growth of a population, initially consisting of N spores, over time as the sum of cells in each of the N imminent subpopulations originating from a single spore. Growth simulations for different initial contamination levels showed that for low N the number of cells in the population at any time is highly variable. An increase in N to levels exceeding 100 spores results in a significant decrease of the above variability and a shorter λ of the population. Considering that the number of G. stearothermophilus surviving spores in the final product is usually very low, the data provided in this work can be used to evaluate the probability distribution of the time-to-spoilage and enable decision-making based on the "acceptable level of risk".
[Mh] Termos MeSH primário: Geobacillus stearothermophilus/crescimento & desenvolvimento
Preservação Biológica/métodos
Esporos Bacterianos/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Geobacillus stearothermophilus/química
Geobacillus stearothermophilus/genética
Preservação Biológica/instrumentação
Esporos Bacterianos/química
Esporos Bacterianos/genética
Temperatura Ambiente
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170822
[Lr] Data última revisão:
170822
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170627
[St] Status:MEDLINE


  9 / 2607 MEDLINE  
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[PMID]:28238534
[Au] Autor:Huen J; Lin CL; Golzarroshan B; Yi WL; Yang WZ; Yuan HS
[Ad] Endereço:Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan 11529, ROC.
[Ti] Título:Structural Insights into a Unique Dimeric DEAD-Box Helicase CshA that Promotes RNA Decay.
[So] Source:Structure;25(3):469-481, 2017 Mar 07.
[Is] ISSN:1878-4186
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:CshA is a dimeric DEAD-box helicase that cooperates with ribonucleases for mRNA turnover. The molecular mechanism for how a dimeric DEAD-box helicase aids in RNA decay remains unknown. Here, we report the crystal structure and small-angle X-ray scattering solution structure of the CshA from Geobacillus stearothermophilus. In contrast to typical monomeric DEAD-box helicases, CshA is exclusively a dimeric protein with the RecA-like domains of each protomer forming a V-shaped structure. We show that the C-terminal domains protruding outward from the tip of the V-shaped structure is critical for mediating strong RNA binding and is crucial for efficient RNA-dependent ATP hydrolysis. We also show that RNA remains bound with CshA during ATP hydrolysis cycles and thus bulk RNAs could be unwound and degraded in a processive manner through cooperation between exoribonucleases and CshA. A dimeric helicase is hence preserved in RNA-degrading machinery for efficient RNA turnover in prokaryotes and eukaryotes.
[Mh] Termos MeSH primário: RNA Helicases DEAD-box/química
RNA Helicases DEAD-box/metabolismo
Geobacillus stearothermophilus/metabolismo
RNA/metabolismo
[Mh] Termos MeSH secundário: Trifosfato de Adenosina/metabolismo
Proteínas de Bactérias/química
Proteínas de Bactérias/metabolismo
Cristalografia por Raios X
Exorribonucleases/metabolismo
Hidrólise
Modelos Moleculares
Multimerização Proteica
Estabilidade de RNA
Espalhamento a Baixo Ângulo
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 63231-63-0 (RNA); 8L70Q75FXE (Adenosine Triphosphate); EC 3.1.- (Exoribonucleases); EC 3.6.4.13 (DEAD-box RNA Helicases)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170823
[Lr] Data última revisão:
170823
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170228
[St] Status:MEDLINE


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[PMID]:28213016
[Au] Autor:Mtimet N; Trunet C; Mathot AG; Venaille L; Leguérinel I; Coroller L; Couvert O
[Ad] Endereço:Université de Brest, EA3882, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, UMT14.01 SPORE-RISK, IBSAM, 6 rue de l'Université, F-29334, Quimper, France; BONDUELLE, rue Nicolas Appert BP 30173, 59653, Villeneuve d'Ascq, France.
[Ti] Título:Walking dead: Permeabilization of heat-treated Geobacillus stearothermophilus ATCC 12980 spores under growth-preventing conditions.
[So] Source:Food Microbiol;64:126-134, 2017 Jun.
[Is] ISSN:1095-9998
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Although heat treatment is probably the oldest and the most common method used to inactivate spores in food processes, the specific mechanism of heat killing of spores is still not fully understood. The purpose of this study is to investigate the evolution of the permeabilization and the viability of heat-treated spores during storage under growth-preventing conditions. Geobacillus stearothermophilus spores were heat-treated under various conditions of temperature and pH, and then stored under conditions of temperature and pH that prevent growth. Spore survival was evaluated by count plating immediately after heat treatment, and then during storage over a period of months. Flow cytometry analyses were performed to investigate the Syto 9 permeability of heat-treated spores. Sub-lethally heat-treated spores of G. stearothermophilus were physically committed to permeabilization after heat treatment. However, prolonged heat treatment may abolish the spore permeabilization and block heat-treated spores in the refractive state. However, viability loss and permeabilization during heat treatment seem to be two different mechanisms that occur independently, and the loss of permeabilization properties takes place at a much slower rate than spore killing. Under growth-preventing conditions, viable heat-treated spores presumably lose their viability due to the permeabilization phenomena, which makes them more susceptible to the action of adverse conditions precluding growth.
[Mh] Termos MeSH primário: Geobacillus stearothermophilus/fisiologia
Temperatura Alta
Esporos Bacterianos/fisiologia
[Mh] Termos MeSH secundário: Contagem de Colônia Microbiana
Geobacillus stearothermophilus/crescimento & desenvolvimento
Concentração de Íons de Hidrogênio
Modelos Lineares
Viabilidade Microbiana
Modelos Biológicos
Permeabilidade
Esporos Bacterianos/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170314
[Lr] Data última revisão:
170314
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170219
[St] Status:MEDLINE



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