Base de dados : MEDLINE
Pesquisa : D09.894.417.313 [Categoria DeCS]
Referências encontradas : 1667 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 167 ir para página                         

  1 / 1667 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28941463
[Au] Autor:Vorobyeva NN; Kurilova SA; Anashkin VA; Rodina EV
[Ad] Endereço:Lomonosov Moscow State University, Faculty of Chemistry, Moscow, 119991, Russia. nvorob@yandex.ru.
[Ti] Título:Inhibition of Escherichia coli Inorganic Pyrophosphatase by Fructose-1-phosphate.
[So] Source:Biochemistry (Mosc);82(8):953-956, 2017 Aug.
[Is] ISSN:1608-3040
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Pyrophosphate regulates vital cellular reactions, and its level in E. coli cells is under the ultimate control of inorganic pyrophosphatase. The mechanisms involved in the regulation of pyrophosphatase activity still need to be elucidated. The present study demonstrated that fructose-1-phosphate inhibits pyrophosphatase activity by a mechanism not involving competition with substrate for binding to the active site. The inhibition constant governing the binding of the inhibitor to the enzyme-substrate complex is 1.1 mM. Substitutions of Lys112, Lys115, Lys148, and Arg43 in the regulatory site completely or partially abolished the inhibition. Thus, Fru-1-P is a physiological inhibitor of pyrophosphatase that acts via a regulatory site in this enzyme.
[Mh] Termos MeSH primário: Proteínas de Escherichia coli/metabolismo
Escherichia coli/enzimologia
Frutosefosfatos/metabolismo
Pirofosfatase Inorgânica/metabolismo
[Mh] Termos MeSH secundário: Regulação Alostérica
Domínio Catalítico
Proteínas de Escherichia coli/antagonistas & inibidores
Proteínas de Escherichia coli/genética
Frutosefosfatos/química
Hidrólise
Pirofosfatase Inorgânica/antagonistas & inibidores
Pirofosfatase Inorgânica/genética
Cinética
Mutagênese Sítio-Dirigida
Ligação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Escherichia coli Proteins); 0 (Fructosephosphates); 15978-08-2 (fructose-1-phosphate); EC 3.6.1.1 (Inorganic Pyrophosphatase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171025
[Lr] Data última revisão:
171025
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170925
[St] Status:MEDLINE
[do] DOI:10.1134/S0006297917080107


  2 / 1667 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28726643
[Au] Autor:Castro-Fernandez V; Herrera-Morande A; Zamora R; Merino F; Gonzalez-Ordenes F; Padilla-Salinas F; Pereira HM; Brandão-Neto J; Garratt RC; Guixe V
[Ad] Endereço:From the Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 800003, Chile, vcasfe@ug.uchile.cl.
[Ti] Título:Reconstructed ancestral enzymes reveal that negative selection drove the evolution of substrate specificity in ADP-dependent kinases.
[So] Source:J Biol Chem;292(38):15598-15610, 2017 Sep 22.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:One central goal in molecular evolution is to pinpoint the mechanisms and evolutionary forces that cause an enzyme to change its substrate specificity; however, these processes remain largely unexplored. Using the glycolytic ADP-dependent kinases of archaea, including the orders , , and , as a model and employing an approach involving paleoenzymology, evolutionary statistics, and protein structural analysis, we could track changes in substrate specificity during ADP-dependent kinase evolution along with the structural determinants of these changes. To do so, we studied five key resurrected ancestral enzymes as well as their extant counterparts. We found that a major shift in function from a bifunctional ancestor that could phosphorylate either glucose or fructose 6-phosphate (fructose-6-P) as a substrate to a fructose 6-P-specific enzyme was started by a single amino acid substitution resulting in negative selection with a ground-state mode against glucose and a subsequent 1,600-fold change in specificity of the ancestral protein. This change rendered the residual phosphorylation of glucose a promiscuous and physiologically irrelevant activity, highlighting how promiscuity may be an evolutionary vestige of ancestral enzyme activities, which have been eliminated over time. We also could reconstruct the evolutionary history of substrate utilization by using an evolutionary model of discrete binary characters, indicating that substrate uses can be discretely lost or acquired during enzyme evolution. These findings exemplify how negative selection and subtle enzyme changes can lead to major evolutionary shifts in function, which can subsequently generate important adaptive advantages, for example, in improving glycolytic efficiency in .
[Mh] Termos MeSH primário: Complexos de ATP Sintetase/metabolismo
Evolução Molecular
[Mh] Termos MeSH secundário: Complexos de ATP Sintetase/química
Complexos de ATP Sintetase/genética
Sequência de Aminoácidos
Euryarchaeota/enzimologia
Frutosefosfatos/metabolismo
Glucose/metabolismo
Cinética
Modelos Moleculares
Mutação
Filogenia
Conformação Proteica
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fructosephosphates); 6814-87-5 (fructose-6-phosphate); EC 2.7.4.- (ATP Synthetase Complexes); IY9XDZ35W2 (Glucose)
[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:170721
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.790865


  3 / 1667 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28545955
[Au] Autor:Ismail R; Ul Hussain M
[Ad] Endereço:Department of Biotechnology, Hazratbal Srinagar, University of Kashmir, Jammu and Kashmir, India.
[Ti] Título:The up regulation of phosphofructokinase1 (PFK1) protein during chemically induced hypoxia is mediated by the hypoxia-responsive internal ribosome entry site (IRES) element, present in its 5'untranslated region.
[So] Source:Biochimie;139:38-45, 2017 Aug.
[Is] ISSN:1638-6183
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Astrocytes cope-up the hypoxia conditions by up regulating the activity of the enzymes catalyzing the irreversible steps of the glycolytic pathway. The phosphofructokinase1 (PFK1), which converts fructose-6-phosphate to fructose-1, 6-bisphosphate, is the major regulatory enzyme of the glycolytic pathway. For this purpose, we investigated the expression regulation of the PFK1 during chemically induced hypoxia. PRINCIPAL RESULT: After 48 h of the chemically induced hypoxia induction of the C6 glioma cells, the PFK1 protein depicted strong up regulation, with no appreciable change in its mRNA levels. The di-cistronic assay indicated the presence of a weak internal ribosome entry site (IRES) element in the 5'UTR of the PFK1 mRNA. Interestingly, the weak IRES element of the PFK1 was strongly up regulated after 48 h of the chemically induced hypoxia, indicative of a possible mechanism responsible for the induction of the PFK1 protein. The authenticity of the hypoxia-regulated IRES element of the PFK1, relative to the presence of the cryptic promoter element and/or the cryptic splicing was established using promoterless di-cistronic assay and the RT-PCR analysis. Moreover, the ectopic expression of the polypyrimidine tract binding (PTB) protein resulted in the enhanced activity of the IRES element of the PFK1. Additionally, it was established that the chemically induced hypoxia resulted in the increased shuttling of the PTB from the cell nucleus to the cytosol. MAJOR CONCLUSION: The presence of a hypoxia responsive IRES element, in the 5'UTR of the PFK1 was established to be the possible mechanism responsible for the up regulation of the PFK1 protein. Our data provides an interesting mechanism that may explain the increased glycolytic capacity of the astrocytes after brain hypoxia.
[Mh] Termos MeSH primário: Regiões 5´ não Traduzidas/genética
Glioma/metabolismo
Hipóxia/metabolismo
Sítios Internos de Entrada Ribossomal/genética
Fosfofrutoquinase-1/metabolismo
Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo
[Mh] Termos MeSH secundário: Animais
Sequência de Bases
Western Blotting
Cobalto/toxicidade
Frutosefosfatos
Glioma/genética
Glioma/patologia
Hipóxia/induzido quimicamente
Hipóxia/genética
Fosfofrutoquinase-1/genética
Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética
Regiões Promotoras Genéticas/genética
RNA Mensageiro/genética
Ratos
Reação em Cadeia da Polimerase em Tempo Real
Reação em Cadeia da Polimerase Via Transcriptase Reversa
Ativação Transcricional
Células Tumorais Cultivadas
Regulação para Cima
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (5' Untranslated Regions); 0 (Fructosephosphates); 0 (Internal Ribosome Entry Sites); 0 (RNA, Messenger); 139076-35-0 (Polypyrimidine Tract-Binding Protein); 3G0H8C9362 (Cobalt); 6814-87-5 (fructose-6-phosphate); EC 2.7.1.11 (Phosphofructokinase-1); EVS87XF13W (cobaltous chloride)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170912
[Lr] Data última revisão:
170912
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170527
[St] Status:MEDLINE


  4 / 1667 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28011870
[Au] Autor:Hartman MD; Figueroa CM; Arias DG; Iglesias AA
[Ad] Endereço:Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Colectora Ruta Nacional, Santa Fe, Argentina.
[Ti] Título:Inhibition of Recombinant Aldose-6-Phosphate Reductase from Peach Leaves by Hexose-Phosphates, Inorganic Phosphate and Oxidants.
[So] Source:Plant Cell Physiol;58(1):145-155, 2017 01 01.
[Is] ISSN:1471-9053
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Glucitol, also known as sorbitol, is a major photosynthetic product in plants from the Rosaceae family. This sugar alcohol is synthesized from glucose-6-phosphate by the combined activities of aldose-6-phosphate reductase (Ald6PRase) and glucitol-6-phosphatase. In this work we show the purification and characterization of recombinant Ald6PRase from peach leaves. The recombinant enzyme was inhibited by glucose-1-phosphate, fructose-6-phosphate, fructose-1,6-bisphosphate and orthophosphate. Oxidizing agents irreversibly inhibited the enzyme and produced protein precipitation. Enzyme thiolation with oxidized glutathione protected the enzyme from insolubilization caused by diamide, while incubation with NADP+ (one of the substrates) completely prevented enzyme precipitation. Our results suggest that Ald6PRase is finely regulated to control carbon partitioning in peach leaves.
[Mh] Termos MeSH primário: Aldeído Redutase/metabolismo
Folhas de Planta/enzimologia
Proteínas de Plantas/metabolismo
Prunus domestica/enzimologia
[Mh] Termos MeSH secundário: Aldeído Redutase/antagonistas & inibidores
Aldeído Redutase/genética
Frutosedifosfatos/metabolismo
Frutosedifosfatos/farmacologia
Frutosefosfatos/metabolismo
Frutosefosfatos/farmacologia
Glucofosfatos/metabolismo
Glucofosfatos/farmacologia
Dissulfeto de Glutationa/metabolismo
Hexosefosfatos/metabolismo
Hexosefosfatos/farmacologia
Immunoblotting
Cinética
Modelos Biológicos
NADP/metabolismo
Oxidantes/metabolismo
Oxidantes/farmacologia
Fosfatos/metabolismo
Fosfatos/farmacologia
Filogenia
Folhas de Planta/genética
Proteínas de Plantas/classificação
Proteínas de Plantas/genética
Prunus domestica/genética
Proteínas Recombinantes/metabolismo
Especificidade por Substrato
Compostos de Sulfidrila/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fructosediphosphates); 0 (Fructosephosphates); 0 (Glucosephosphates); 0 (Hexosephosphates); 0 (Oxidants); 0 (Phosphates); 0 (Plant Proteins); 0 (Recombinant Proteins); 0 (Sulfhydryl Compounds); 53-59-8 (NADP); 6814-87-5 (fructose-6-phosphate); CIX3U01VAU (glucose-1-phosphate); EC 1.1.1.21 (Aldehyde Reductase); M7522JYX1H (fructose-1,6-diphosphate); ULW86O013H (Glutathione Disulfide)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170723
[Lr] Data última revisão:
170723
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161225
[St] Status:MEDLINE
[do] DOI:10.1093/pcp/pcw180


  5 / 1667 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27802586
[Au] Autor:Crochet RB; Kim JD; Lee H; Yim YS; Kim SG; Neau D; Lee YH
[Ad] Endereço:Departments of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803.
[Ti] Título:Crystal structure of heart 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB2) and the inhibitory influence of citrate on substrate binding.
[So] Source:Proteins;85(1):117-124, 2017 Jan.
[Is] ISSN:1097-0134
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The heart-specific isoform of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB2) is an important regulator of glycolytic flux in cardiac cells. Here, we present the crystal structures of two PFKFB2 orthologues, human and bovine, at resolutions of 2.0 and 1.8 Å, respectively. Citrate, a TCA cycle intermediate and well-known inhibitor of PFKFB2, co-crystallized in the 2-kinase domains of both orthologues, occupying the fructose-6-phosphate binding-site and extending into the γ-phosphate binding pocket of ATP. This steric and electrostatic occlusion of the γ-phosphate site by citrate proved highly consequential to the binding of co-complexed ATP analogues. The bovine structure, which co-crystallized with ADP, closely resembled the overall structure of other PFKFB isoforms, with ADP mimicking the catalytic binding mode of ATP. The human structure, on the other hand, co-complexed with AMPPNP, which, unlike ADP, contains a γ-phosphate. The presence of this γ-phosphate made adoption of the catalytic ATP binding mode impossible for AMPPNP, forcing the analogue to bind atypically with concomitant conformational changes to the ATP binding-pocket. Inhibition kinetics were used to validate the structural observations, confirming citrate's inhibition mechanism as competitive for F6P and noncompetitive for ATP. Together, these structural and kinetic data establish a molecular basis for citrate's negative feed-back loop of the glycolytic pathway via PFKFB2. Proteins 2016; 85:117-124. © 2016 Wiley Periodicals, Inc.
[Mh] Termos MeSH primário: Difosfato de Adenosina/química
Trifosfato de Adenosina/química
Ácido Cítrico/química
Frutosefosfatos/química
Isoenzimas/química
Miocárdio/química
Fosfofrutoquinase-2/química
[Mh] Termos MeSH secundário: Difosfato de Adenosina/metabolismo
Trifosfato de Adenosina/metabolismo
Adenilil Imidodifosfato/química
Adenilil Imidodifosfato/metabolismo
Animais
Sítios de Ligação
Bovinos
Ácido Cítrico/metabolismo
Clonagem Molecular
Cristalografia por Raios X
Escherichia coli/genética
Escherichia coli/metabolismo
Frutosefosfatos/metabolismo
Expressão Gênica
Seres Humanos
Isoenzimas/genética
Isoenzimas/metabolismo
Cinética
Modelos Moleculares
Miocárdio/enzimologia
Fosfofrutoquinase-2/genética
Fosfofrutoquinase-2/metabolismo
Ligação Proteica
Domínios e Motivos de Interação entre Proteínas
Estrutura Secundária de Proteína
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Especificidade da Espécie
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fructosephosphates); 0 (Isoenzymes); 0 (Recombinant Proteins); 25612-73-1 (Adenylyl Imidodiphosphate); 2968PHW8QP (Citric Acid); 61D2G4IYVH (Adenosine Diphosphate); 6814-87-5 (fructose-6-phosphate); 8L70Q75FXE (Adenosine Triphosphate); EC 2.7.1.105 (PFKFB2 protein, human); EC 2.7.1.105 (Phosphofructokinase-2)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170724
[Lr] Data última revisão:
170724
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161102
[St] Status:MEDLINE
[do] DOI:10.1002/prot.25204


  6 / 1667 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Alves, Sandra
Texto completo
[PMID]:27727023
[Au] Autor:Darii E; Alves S; Gimbert Y; Perret A; Tabet JC
[Ad] Endereço:CEA, Institut de Génomique, Génoscope, CNRS-UMR8030, Université d'Evry Val d'Essonne Evry, France. Electronic address: edariy@genoscope.cns.fr.
[Ti] Título:Meaning and consequence of the coexistence of competitive hydrogen bond/salt forms on the dissociation orientation of non-covalent complexes.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1047:45-58, 2017 Mar 15.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Non-covalent complexes (NCC) between hexose monophosphates (HexP) and arginine (R) were analyzed using ESI MS and MS/MS in negative mode under different (hard, HC and soft, SC) desolvation conditions. High resolution mass spectrometry (HRMS) revealed the presence of different ionic species, namely, homo- and heteromultimers of R and HexP. Deprotonated heterodimers and corresponding sodiated species were enhanced under HC likely due to a decrease in available charge number associated with the reduction of H /Na exchange. The quantum calculations showed that the formation of covalent systems is very little exothermic, therefore, such systems are disfavored. Desolvation dependent CID spectra of deprotonated [(HexP+R)‒H] complexes demonstrated that they can exist within the hydrogen bond (HB) and salt bridge (SB) forms, yielding either NCC separation or covalent bond cleavages, respectively. Although HB forms are the main species, they cannot survive under HC; therefore, the minor SB forms became detectable. Energy-resolved mass spectrometry (ERMS) experiments revealed diagnostic fragment ions from both SB and HB forms, providing evidence that these isomeric forms are inconvertible. SB formation should result from the ionic interactions of highly acidic group of HexP with strongly basic guanidine group of arginine and thus requires an arginine zwitterion (ZW) form. This was confirmed by quantum calculations. Ion-ion interactions are significantly affected by the presence of sodium cation as demonstrated by the fragmentation patterns of sodiated complex species. Regarding CID data, only SB between protonated amino group of R and deprotonated phosphate group of HexP could be suggested, but the primary amine is not enough basic then, the SB must be fleeting. Nevertheless, the observation of the covalent bond cleavages suggests the presence of structures with a free negative charge able to induce fragmentations. Indeed, according to quantum calculations, solvated salt (SS) systems involving Na /COO salt solvated by neutral phosphate and negative charge on sugar ring are preferentially formed.
[Mh] Termos MeSH primário: Arginina/química
Frutosefosfatos/química
Glucose-6-Fosfato/química
Glucofosfatos/química
[Mh] Termos MeSH secundário: Ligações de Hidrogênio
Isomerismo
Modelos Moleculares
Espectrometria de Massas por Ionização por Electrospray
Espectrometria de Massas em Tandem
Termodinâmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fructosephosphates); 0 (Glucosephosphates); 15978-08-2 (fructose-1-phosphate); 56-73-5 (Glucose-6-Phosphate); 6814-87-5 (fructose-6-phosphate); 94ZLA3W45F (Arginine); CIX3U01VAU (glucose-1-phosphate)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170322
[Lr] Data última revisão:
170322
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161012
[St] Status:MEDLINE


  7 / 1667 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27591700
[Au] Autor:Villalobos P; Soto F; Baez M; Babul J
[Ad] Endereço:Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile.
[Ti] Título:Regulatory network of the allosteric ATP inhibition of E. coli phosphofructokinase-2 studied by hybrid dimers.
[So] Source:Biochimie;128-129:209-16, 2016 Sep-Oct.
[Is] ISSN:1638-6183
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:We have proposed an allosteric ATP inhibition mechanism of Pfk-2 determining the structure of different forms of the enzyme together with a kinetic enzyme analysis. Here we complement the mechanism by using hybrid oligomers of the homodimeric enzyme to get insights about the allosteric communication pathways between the same sites or different ones located in different subunits. Kinetic analysis of the hybrid enzymes indicate that homotropic interactions between allosteric sites for ATP or between substrate sites for fructose-6-P have a minor effect on the enzymatic inhibition induced by ATP. In fact, the sigmoid response for fructose-6-P observed at elevated ATP concentrations can be eliminated even though the enzymatic inhibition is still operative. Nevertheless, leverage coupling analysis supports heterotropic interactions between the allosteric ATP and fructose-6-P binding occurring between and within each subunit.
[Mh] Termos MeSH primário: Trifosfato de Adenosina/metabolismo
Proteínas de Escherichia coli/metabolismo
Frutosefosfatos/metabolismo
Fosfofrutoquinase-2/metabolismo
[Mh] Termos MeSH secundário: Trifosfato de Adenosina/química
Trifosfato de Adenosina/farmacologia
Regulação Alostérica
Sítio Alostérico
Sítios de Ligação/genética
Biocatálise/efeitos dos fármacos
Simulação por Computador
Escherichia coli/enzimologia
Escherichia coli/metabolismo
Proteínas de Escherichia coli/química
Proteínas de Escherichia coli/genética
Frutosefosfatos/química
Cinética
Modelos Moleculares
Estrutura Molecular
Mutação
Fosfofrutoquinase-2/antagonistas & inibidores
Fosfofrutoquinase-2/química
Ligação Proteica
Domínios Proteicos
Multimerização Proteica
Subunidades Proteicas/química
Subunidades Proteicas/metabolismo
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Escherichia coli Proteins); 0 (Fructosephosphates); 0 (Protein Subunits); 6814-87-5 (fructose-6-phosphate); 8L70Q75FXE (Adenosine Triphosphate); EC 2.7.1.105 (Phosphofructokinase-2)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170131
[Lr] Data última revisão:
170131
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160904
[St] Status:MEDLINE


  8 / 1667 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27481705
[Au] Autor:Ogawa T; Murakami K; Yoshino M
[Ad] Endereço:Department of Biochemistry, School of Medicine, Aichi Medical University, Yazako-Karimata 1-1, Nagakute, Aichi 480-1195, Japan.
[Ti] Título:Inhibition by fructose 1,6-bisphosphate of transaldolase from Escherichia coli.
[So] Source:FEMS Microbiol Lett;363(17), 2016 Sep.
[Is] ISSN:1574-6968
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The effect of fructose 1,6-bisphosphate (Fru 1,6-P2) on the regulatory enzymes of pentose phosphate pathway of Escherichia coli was examined. Fru 1,6-P2 inhibited E. coli transaldolase (EC 2.2.1.2) competitively against fructose 6-phosphate and uncompetitively against erythrose 4-phosphate, whereas Fru 1,6-P2 did not affect glucose 6-phosphate dehydrogenase (EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (EC 1.1.1.44). Kinetic results can be explained by assuming that transaldolase has two kinds of binding sites for Fru 1,6-P2: a competitive binding site for fructose 6-phosphate and a second binding site on the enzyme-erythrose 4-phosphate complex. Fru 1,6-P2 increased resulting from the stimulation of glycolysis, can inhibit transaldolase and further participates in the elevation of the concentration of ribose 5-phosphate that can be preferentially utilized for anabolic reaction in exponential phase of E. coli.
[Mh] Termos MeSH primário: Escherichia coli/metabolismo
Frutosedifosfatos/metabolismo
Via de Pentose Fosfato/efeitos dos fármacos
Transaldolase/antagonistas & inibidores
[Mh] Termos MeSH secundário: Sítios de Ligação
Ligação Competitiva
Escherichia coli/efeitos dos fármacos
Escherichia coli/enzimologia
Escherichia coli/crescimento & desenvolvimento
Frutosedifosfatos/farmacologia
Frutosefosfatos/farmacologia
Glucosefosfato Desidrogenase/metabolismo
Glicólise/efeitos dos fármacos
Cinética
Fosfogluconato Desidrogenase/metabolismo
Ribosemonofosfatos/metabolismo
Fosfatos Açúcares/farmacologia
Transaldolase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fructosediphosphates); 0 (Fructosephosphates); 0 (Ribosemonophosphates); 0 (Sugar Phosphates); 4B2428FLTO (ribose-5-phosphate); 585-18-2 (erythrose 4-phosphate); 6814-87-5 (fructose-6-phosphate); EC 1.1.1.43 (Phosphogluconate Dehydrogenase); EC 1.1.1.49 (Glucosephosphate Dehydrogenase); EC 2.2.1.2 (Transaldolase); M7522JYX1H (fructose-1,6-diphosphate)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160803
[St] Status:MEDLINE


  9 / 1667 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27477958
[Au] Autor:Whitaker AM; Reinhart GD
[Ad] Endereço:Department of Biochemistry and Biophysics, Texas A&M University and Texas AgriLife Research, 2128 TAMU, College Station, TX, 77843-2128, USA.
[Ti] Título:The effect of introducing small cavities on the allosteric inhibition of phosphofructokinase from Bacillus stearothermophilus.
[So] Source:Arch Biochem Biophys;607:1-6, 2016 Oct 01.
[Is] ISSN:1096-0384
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The allosteric coupling free energy between ligands fructose-6-phosphate (Fru-6-P) and phospho(enol)pyruvate (PEP) for phosphofructokinase-1 (PFK) from the moderate thermophile, Bacillus stearothermophilus (BsPFK), results from compensating enthalpy and entropy components. In BsPFK the positive coupling free energy that defines inhibition is opposite in sign from the negative enthalpy term and is therefore determined by the larger absolute value of the negative entropy term. Variants of BsPFK were made to determine the effect of adding small cavities to the structure on the allosteric function of the enzyme. The BsPFK Ile → Val (cavity containing) mutants have varied values for the coupling free energy between PEP and Fru-6-P, indicating that the modifications altered the effectiveness of PEP as an inhibitor. Notably, the mutation I153V had a substantial positive impact on the magnitude of inhibition by PEP. Van't Hoff analysis determined that this is the result of decreased entropy-enthalpy compensation with a larger change in the enthalpy term compared to the entropy term.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Geobacillus stearothermophilus/enzimologia
Fosfofrutoquinases/química
[Mh] Termos MeSH secundário: Sítio Alostérico
Proteínas de Bactérias/genética
Catálise
Cristalografia por Raios X
Frutosefosfatos/química
Geobacillus stearothermophilus/genética
Concentração de Íons de Hidrogênio
Cinética
Conformação Molecular
Mutagênese Sítio-Dirigida
Mutação
Fosfoenolpiruvato/química
Fosfofrutoquinases/genética
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Fructosephosphates); 6814-87-5 (fructose-6-phosphate); 73-89-2 (Phosphoenolpyruvate); EC 2.7.1 - (Phosphofructokinases)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171001
[Lr] Data última revisão:
171001
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160802
[St] Status:MEDLINE


  10 / 1667 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:27258673
[Au] Autor:Hansen AL; Behrman EJ
[Ad] Endereço:Campus Chemical Instrument Center, The Ohio State University, 496 W. 12th Avenue, Columbus, OH 43210, USA. Electronic address: Hansen.434@osu.edu.
[Ti] Título:Synthesis of 6-phosphofructose aspartic acid and some related Amadori compounds.
[So] Source:Carbohydr Res;431:1-5, 2016 Aug 05.
[Is] ISSN:1873-426X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:We describe the synthesis and characterization of 6-phosphofructose-aspartic acid, an intermediate in the metabolism of fructose-asparagine by Salmonella. We also report improved syntheses of fructose-asparagine itself and of fructose-aspartic acid.
[Mh] Termos MeSH primário: Ácido Aspártico/análogos & derivados
Frutosefosfatos/síntese química
[Mh] Termos MeSH secundário: Asparagina/química
Ácido Aspártico/química
Frutosefosfatos/química
Estrutura Molecular
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fructosephosphates); 30KYC7MIAI (Aspartic Acid); 7006-34-0 (Asparagine)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170805
[Lr] Data última revisão:
170805
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160604
[St] Status:MEDLINE



página 1 de 167 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