Base de dados : MEDLINE
Pesquisa : D12.125.068 [Categoria DeCS]
Referências encontradas : 252 [refinar]
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[PMID]:28946005
[Au] Autor:Alam SB; Reade R; Theilmann J; Rochon D
[Ad] Endereço:Faculty of Land and Food Systems, University of British Columbia, Vancouver, B.C., Canada.
[Ti] Título:Evidence for the role of basic amino acids in the coat protein arm region of Cucumber necrosis virus in particle assembly and selective encapsidation of viral RNA.
[So] Source:Virology;512:83-94, 2017 Dec.
[Is] ISSN:1096-0341
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Cucumber necrosis virus (CNV) is a T = 3 icosahedral virus with a (+)ssRNA genome. The N-terminal CNV coat protein arm contains a conserved, highly basic sequence ("KGRKPR"), which we postulate is involved in RNA encapsidation during virion assembly. Seven mutants were constructed by altering the CNV "KGRKPR" sequence; the four basic residues were mutated to alanine individually, in pairs, or in total. Virion accumulation and vRNA encapsidation were significantly reduced in mutants containing two or four substitutions and virion morphology was also affected, where both T = 1 and intermediate-sized particles were produced. Mutants with two or four substitutions encapsidated significantly greater levels of truncated RNA than that of WT, suggesting that basic residues in the "KGRKPR" sequence are important for encapsidation of full-length CNV RNA. Interestingly, "KGRKPR" mutants also encapsidated relatively higher levels of host RNA, suggesting that the "KGRKPR" sequence also contributes to selective encapsidation of CNV RNA.
[Mh] Termos MeSH primário: Aminoácidos Básicos/química
Proteínas do Capsídeo/metabolismo
Vírus de Plantas/metabolismo
RNA Viral/fisiologia
Montagem de Vírus/fisiologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas do Capsídeo/química
Proteínas do Capsídeo/genética
Mutação
Vírus de Plantas/genética
Conformação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Basic); 0 (Capsid Proteins); 0 (RNA, Viral)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170926
[St] Status:MEDLINE


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[PMID]:28695314
[Au] Autor:Regina TMR; Galluccio M; Scalise M; Pochini L; Indiveri C
[Ad] Endereço:Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036, Arcavacata di Rende, Cosenza, Italy.
[Ti] Título:Bacterial production and reconstitution in proteoliposomes of Solanum lycopersicum CAT2: a transporter of basic amino acids and organic cations.
[So] Source:Plant Mol Biol;94(6):657-667, 2017 Aug.
[Is] ISSN:1573-5028
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:KEY MESSAGE: The vacuolar SlCAT2 was cloned, over-produced in E. coli and reconstituted in proteoliposomes. Arg, Ornithine and Lys were identified as substrates. Unexpectedly, also the organic cations Tetraethylammonium and Acetylcholine were transported indicating involvement of SlCAT2 in signaling. In land plants several transporters are involved in ion and metabolite flux across membranes of cells or intracellular organelles. The vacuolar amino acid transporter CAT2 from Solanum lycopersicum was investigated in this work. SlCAT2 was cloned from tomato flower cDNA, over-produced in Escherichia coli and purified by Nichel-chelating chromatography. For functional studies, the transporter was reconstituted in proteoliposomes. Competence of SlCAT2 for Arg transport was demonstrated measuring uptake of [ H]Arg in proteoliposomes which was trans-stimulated by internal Arg or ornithine. Uptake of [ H]Ornithine and [ H]Lys was also detected at lower efficiency with respect to [ H]Arg. Transport was activated by the presence of intraliposomal ATP suggesting regulation by the nucleotide. The prototype for organic cations tetraethylammonium (TEA) was also transported by SlCAT2. However, scarce reciprocal inhibition between TEA and Arg was found, while the biguanide metformin was able to strongly inhibit uptake of both substrates. These findings suggest that amino acids and organic cations may interact with the transporter through different functional groups some of which are common for the two types of substrates. Interestingly, reconstituted SlCAT2 showed competence for acetylcholine transport, which was also inhibited by metformin. Kinetics of Arg and Ach transport were performed from which Km values of 0.29 and 0.79 mM were derived, respectively.
[Mh] Termos MeSH primário: Proteínas de Transporte/metabolismo
Lycopersicon esculentum/metabolismo
Proteínas de Plantas/metabolismo
Proteolipídeos/metabolismo
[Mh] Termos MeSH secundário: Acetilcolina/metabolismo
Aminoácidos Básicos/metabolismo
Arginina/metabolismo
Transporte Biológico
Proteínas de Transporte/genética
Cátions/metabolismo
Clonagem Molecular
Escherichia coli/genética
Lycopersicon esculentum/genética
Lisina/metabolismo
Ornitina/metabolismo
Proteínas de Plantas/genética
Proteínas de Plantas/isolamento & purificação
Proteínas Recombinantes/genética
Proteínas Recombinantes/isolamento & purificação
Tetraetilamônio/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Basic); 0 (Carrier Proteins); 0 (Cations); 0 (Plant Proteins); 0 (Proteolipids); 0 (Recombinant Proteins); 0 (proteoliposomes); 66-40-0 (Tetraethylammonium); 94ZLA3W45F (Arginine); E524N2IXA3 (Ornithine); K3Z4F929H6 (Lysine); N9YNS0M02X (Acetylcholine)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170814
[Lr] Data última revisão:
170814
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170712
[St] Status:MEDLINE
[do] DOI:10.1007/s11103-017-0632-6


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[PMID]:28530165
[Au] Autor:Hara K; Kashiwagi T; Hamada N; Watanabe H
[Ad] Endereço:Department of Infection Control and Prevention, Kurume University School of Medicine, Fukuoka 830-0011, Japan.
[Ti] Título:Basic amino acids in the N-terminal half of the PB2 subunit of influenza virus RNA polymerase are involved in both transcription and replication.
[So] Source:J Gen Virol;98(5):900-905, 2017 May.
[Is] ISSN:1465-2099
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The PB2 subunit of influenza virus RNA polymerase is known to be involved in the initiation of transcription of the virus genome via cap binding. However, other specific roles of PB2 for viral RNA synthesis are not well understood. Here, we demonstrate that basic residues, 124R, 142R, 143R, 268R and 331K/332R, in the N-terminal half of PB2 are important for the polymerase activity. Notably, R124A mutation remarkably reduced the synthesis of mRNA, cRNA and vRNA in vivo, which was in good agreement with the data obtained in vitro. Cross-linking studies suggested that a reduction of the polymerase activity in the R124A mutant was due to a significant decrease in binding to the viral RNA promoter. In the three-dimensional structure of the polymerase, 124R is visible through the NTP tunnel and is located close to the polymerase active site. We propose that 124R plays a key role in promoter binding during RNA synthesis.
[Mh] Termos MeSH primário: Aminoácidos Básicos/metabolismo
Orthomyxoviridae/fisiologia
Transcrição Genética
Proteínas Virais/metabolismo
Replicação Viral
[Mh] Termos MeSH secundário: Substituição de Aminoácidos
Aminoácidos Básicos/genética
Domínio Catalítico
Análise Mutacional de DNA
Modelos Moleculares
Conformação Proteica
RNA Complementar/biossíntese
RNA Mensageiro/biossíntese
RNA Viral/biossíntese
Proteínas Virais/química
Proteínas Virais/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Basic); 0 (PB2 protein, influenza virus); 0 (RNA, Complementary); 0 (RNA, Messenger); 0 (RNA, Viral); 0 (Viral Proteins)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170713
[Lr] Data última revisão:
170713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170523
[St] Status:MEDLINE
[do] DOI:10.1099/jgv.0.000750


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[PMID]:28254587
[Au] Autor:Silva RN; Oliveira LCG; Parise CB; Oliveira JR; Severino B; Corvino A; di Vaio P; Temussi PA; Caliendo G; Santagada V; Juliano L; Juliano MA
[Ad] Endereço:Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, Brazil.
[Ti] Título:Activity of human kallikrein-related peptidase 6 (KLK6) on substrates containing sequences of basic amino acids. Is it a processing protease?
[So] Source:Biochim Biophys Acta;1865(5):558-564, 2017 05.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Human kallikrein 6 (KLK6) is highly expressed in the central nervous system and with elevated level in demyelinating disease. KLK6 has a very restricted specificity for arginine (R) and hydrolyses myelin basic protein, protein activator receptors and human ionotropic glutamate receptor subunits. Here we report a previously unreported activity of KLK6 on peptides containing clusters of basic amino acids, as in synthetic fluorogenic peptidyl-Arg-7-amino-4-carbamoylmethylcoumarin (peptidyl-ACC) peptides and FRET peptides in the format of Abz-peptidyl-Q-EDDnp (where Abz=ortho-aminobenzoic acid and Q-EDDnp=glutaminyl-N-(2,4-dinitrophenyl) ethylenediamine), in which pairs or sequences of basic amino acids (R or K) were introduced. Surprisingly, KLK6 hydrolyzed the fluorogenic peptides Bz-A-R R-ACC and Z-R R-MCA between the two R groups, resulting in non-fluorescent products. FRET peptides containing furin processing sequences of human MMP-14, nerve growth factor (NGF), Neurotrophin-3 (NT-3) and Neurotrophin-4 (NT-4) were cleaved by KLK6 at the same position expected by furin. Finally, KLK6 cleaved FRET peptides derived from human proenkephalin after the KR, the more frequent basic residues flanking enkephalins in human proenkephalin sequence. This result suggests the ability of KLK6 to release enkephalin from proenkephalin precursors and resembles furin a canonical processing proteolytic enzyme. Molecular models of peptides were built into the KLK6 structure and the marked preference of the cut between the two R of the examined peptides was related to the extended conformation of the substrates.
[Mh] Termos MeSH primário: Calicreínas/metabolismo
Cinética
Peptídeo Hidrolases/metabolismo
Peptídeos/química
[Mh] Termos MeSH secundário: Aminoácidos Básicos/química
Aminoácidos Básicos/genética
Encefalinas/química
Encefalinas/metabolismo
Transferência Ressonante de Energia de Fluorescência
Furina/química
Furina/metabolismo
Seres Humanos
Hidrólise
Calicreínas/química
Calicreínas/genética
Metaloproteinase 14 da Matriz/química
Metaloproteinase 14 da Matriz/metabolismo
Modelos Moleculares
Fator de Crescimento Neural/química
Fator de Crescimento Neural/metabolismo
Fatores de Crescimento Neural/química
Fatores de Crescimento Neural/metabolismo
Peptídeo Hidrolases/química
Peptídeo Hidrolases/genética
Peptídeos/metabolismo
Conformação Proteica
Precursores de Proteínas/química
Precursores de Proteínas/metabolismo
Proteólise
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Amino Acids, Basic); 0 (Enkephalins); 0 (Nerve Growth Factors); 0 (Peptides); 0 (Protein Precursors); 0 (neurotrophin-3, human); 0 (proenkephalin); 9061-61-4 (Nerve Growth Factor); EC 3.4.- (Peptide Hydrolases); EC 3.4.21.- (KLK6 protein, human); EC 3.4.21.- (Kallikreins); EC 3.4.21.75 (Furin); EC 3.4.24.80 (Matrix Metalloproteinase 14); P658DCA9XD (neurotrophin 4)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171008
[Lr] Data última revisão:
171008
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170304
[St] Status:MEDLINE


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[PMID]:28173691
[Au] Autor:Hu H; Chen K; Li L; Long L; Ding S
[Ad] Endereço:College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, P.R. China.
[Ti] Título:Characterization of the Wild-Type and Truncated Forms of a Neutral GH10 Xylanase from : Roles of C-Terminal Basic Amino Acid-Rich Extension in Its SDS Resistance, Thermostability, and Activity.
[So] Source:J Microbiol Biotechnol;27(4):775-784, 2017 Apr 28.
[Is] ISSN:1738-8872
[Cp] País de publicação:Korea (South)
[La] Idioma:eng
[Ab] Resumo:A neutral xylanase (CcXyn) was identified from . It has a single GH10 catalytic domain with a basic amino acid-rich extension (PVRRK) at the C-terminus. In this study, the wild-type (CcXyn) and C-terminus-truncated xylanase (CcXyn-Δ5C) were heterologously expressed in and their characteristics were comparatively analyzed with aims to examine the effect of this extension on the enzyme function. The circular dichorism analysis indicated that both enzymes in general had a similar structure, but CcXyn-Δ5C contained less α-helices (42.9%) and more random coil contents (35.5%) than CcXyn (47.0% and 32.8%, respectively). Both enzymes had the same pH (7.0) and temperature (45°C) optima, and similar substrate specificity on different xylans. They all hydrolyzed beechwood xylan primarily to xylobiose and xylotriose. The amounts of xylobiose and xylotriose accounted for 91.5% and 92.2% (w/w) of total xylooligosaccharides (XOS) generated from beechwood by CcXyn and CcXyn-Δ5C, respectively. However, truncation of the C-terminal 5-amino-acids extension significantly improved the thermostability, SDS resistance, and pH stability at pH 6.0-9.0. Furthermore, CcXyn-Δ5C exhibited a much lower value than CcXyn (0.27 mg/ml vs 0.83 mg/ml), and therefore, the catalytic efficiency of CcXyn-Δ5C was 2.4-times higher than that of CcXyn. These properties make CcXyn-Δ5C a good model for the structure-function study of (α/ß) -barrel-folded enzymes and a promising candidate for various applications, especially in the detergent industry and XOS production.
[Mh] Termos MeSH primário: Aminoácidos Básicos/química
Coprinus/enzimologia
Endo-1,4-beta-Xilanases/química
Endo-1,4-beta-Xilanases/metabolismo
Proteínas Fúngicas/química
Proteínas Fúngicas/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Coprinus/genética
DNA Fúngico
Dissacarídeos/metabolismo
Ácido Edético/farmacologia
Eletroforese em Gel de Poliacrilamida
Endo-1,4-beta-Xilanases/efeitos dos fármacos
Endo-1,4-beta-Xilanases/genética
Ativação Enzimática
Ensaios Enzimáticos
Estabilidade Enzimática
Escherichia coli/genética
Proteínas Fúngicas/genética
Regulação Fúngica da Expressão Gênica
Genoma Fúngico
Glucuronatos/análise
Glucuronatos/metabolismo
Temperatura Alta
Concentração de Íons de Hidrogênio
Hidrólise
Cinética
Metais/farmacologia
Oligossacarídeos/análise
Oligossacarídeos/metabolismo
Pichia/enzimologia
Alinhamento de Sequência
Dodecilsulfato de Sódio/farmacologia
Especificidade por Substrato
Trissacarídeos/metabolismo
Xilanos/metabolismo
Xilose/análise
Xilose/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Basic); 0 (DNA, Fungal); 0 (Disaccharides); 0 (Fungal Proteins); 0 (Glucuronates); 0 (Metals); 0 (Oligosaccharides); 0 (Trisaccharides); 0 (Xylans); 0 (xylooligosaccharide); 0 (xylotriose); 368GB5141J (Sodium Dodecyl Sulfate); 9G34HU7RV0 (Edetic Acid); A1TA934AKO (Xylose); EC 3.2.1.8 (Endo-1,4-beta Xylanases); ID02R0EG7P (xylobiose)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170209
[St] Status:MEDLINE
[do] DOI:10.4014/jmb.1609.09011


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[PMID]:28069648
[Au] Autor:Morán-Barrio J; Cameranesi MM; Relling V; Limansky AS; Brambilla L; Viale AM
[Ad] Endereço:Instituto de Biología Molecular y Celular de Rosario (IBR), Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, CONICET, Universidad Nacional de Rosario (UNR), Rosario, Argentina.
[Ti] Título:The Acinetobacter Outer Membrane Contains Multiple Specific Channels for Carbapenem ß-Lactams as Revealed by Kinetic Characterization Analyses of Imipenem Permeation into Acinetobacter baylyi Cells.
[So] Source:Antimicrob Agents Chemother;61(3), 2017 Mar.
[Is] ISSN:1098-6596
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The number and type of outer membrane (OM) channels responsible for carbapenem uptake in are still not well defined. Here, we addressed these questions by using as a model species and a combination of methodologies aimed to characterize OM channels in their original membrane environment. Kinetic and competition analyses of imipenem (IPM) uptake by whole cells allowed us to identify different carbapenem-specific OM uptake sites. Comparative analyses of IPM uptake by wild-type (WT) cells and Δ mutants lacking CarO indicated that this OM protein provided a carbapenem uptake site displaying saturable kinetics and common binding sites for basic amino acids compatible with a specific channel. The kinetic analysis uncovered another carbapenem-specific channel displaying a somewhat lower affinity for IPM than that of CarO and, in addition, common binding sites for basic amino acids as determined by competition studies. The use of gene deletion mutants lacking OM proteins proposed to function in carbapenem uptake in indicated that CarO and OprD/OccAB1 mutants displayed low but consistent reductions in susceptibility to different carbapenems, including IPM, meropenem, and ertapenem. These two mutants also showed impaired growth on l-Arg but not on other carbon sources, further supporting a role of CarO and OprD/OccAB1 in basic amino acid and carbapenem uptake. A multiple-carbapenem-channel scenario may provide clues to our understanding of the contribution of OM channel loss or mutation to the carbapenem-resistant phenotype evolved by pathogenic members of the genus.
[Mh] Termos MeSH primário: Acinetobacter/metabolismo
Aminoácidos Básicos/metabolismo
Antibacterianos/metabolismo
Proteínas da Membrana Bacteriana Externa/metabolismo
Imipenem/metabolismo
Porinas/deficiência
[Mh] Termos MeSH secundário: Acinetobacter/genética
Acinetobacter baumannii/genética
Acinetobacter baumannii/metabolismo
Proteínas da Membrana Bacteriana Externa/genética
Transporte Biológico
Membrana Celular/química
Membrana Celular/metabolismo
Evolução Molecular
Deleção de Genes
Expressão Gênica
Cinética
Porinas/genética
Tienamicinas/metabolismo
beta-Lactamas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Basic); 0 (Anti-Bacterial Agents); 0 (Bacterial Outer Membrane Proteins); 0 (Porins); 0 (Thienamycins); 0 (beta-Lactams); 71OTZ9ZE0A (Imipenem); FV9J3JU8B1 (meropenem); G32F6EID2H (ertapenem)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170111
[St] Status:MEDLINE


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[PMID]:28012602
[Au] Autor:Tang M; Zhou Y; Li Y; Zou J; Yang B; Cai L; Zhang X; Liu Q
[Ad] Endereço:State Key Laboratory of Biocontrol, MOE Key Laboratory of Aquatic Product Safety, The Key Laboratory of Gene Engineering of Ministry of Education, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
[Ti] Título:Hydrogen donors and acceptors and basic amino acids jointly contribute to carcinogenesis.
[So] Source:Med Hypotheses;98:42-44, 2017 Jan.
[Is] ISSN:1532-2777
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A hypothesis is postulated that high content of hydrogen donors and acceptors, and basic amino acids cause the intracellular trapping of the H and Cl ions, which increases cancer risks as local formation of HCl is mutagenic to DNA. Other cations such as Ca , and weak acids such as short-chain organic acids may attenuate the intracellular gathering of the H and Cl , two of the most abundant ions in the cells. Current data on increased cancer risks in diabetic and obese patients are consistent with the assumption that hydrogen bonding propensity on glucose, triglycerides and other molecules is among the causative factors.
[Mh] Termos MeSH primário: Aminoácidos/química
Carcinogênese/metabolismo
Hidrogênio/química
[Mh] Termos MeSH secundário: Aminoácidos Básicos
Animais
Ânions
Cálcio/química
Celulose/química
Cloro/química
DNA/análise
Glucose/química
Seres Humanos
Ácido Clorídrico/química
Ligações de Hidrogênio
Camundongos
Camundongos Nus
Camundongos Transgênicos
Mutagênese
Mioglobina/metabolismo
Peptídeos/química
Prótons
Triglicerídeos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids); 0 (Amino Acids, Basic); 0 (Anions); 0 (Myoglobin); 0 (Peptides); 0 (Protons); 0 (Triglycerides); 4R7X1O2820 (Chlorine); 7YNJ3PO35Z (Hydrogen); 9004-34-6 (Cellulose); 9007-49-2 (DNA); IY9XDZ35W2 (Glucose); QTT17582CB (Hydrochloric Acid); SY7Q814VUP (Calcium)
[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:161226
[St] Status:MEDLINE


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[PMID]:27943578
[Au] Autor:Clemmensen C; Jørgensen CV; Smajilovic S; Bräuner-Osborne H
[Ad] Endereço:Faculty of Health and Medical Sciences, Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
[Ti] Título:Robust GLP-1 secretion by basic L-amino acids does not require the GPRC6A receptor.
[So] Source:Diabetes Obes Metab;19(4):599-603, 2017 Apr.
[Is] ISSN:1463-1326
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The G protein-coupled receptor GPRC6A (GPCR, Class C, group 6, subtype A) has been proposed to be a sensor for basic L-amino acids that are hypothesized to translate ingestive behaviour to endocrine information. However, the contribution of the GPRC6A receptor to L-amino acid-induced glucagon-like peptide 1 (GLP-1) secretion is unclear. Therefore, to discover whether the GPRC6A receptor is indispensible for amino acid-induced secretion of GLP-1, we treated, with oral gavage, GPRC6A knock-out (KO) and wild-type (WT) littermate mice with GPRC6A ligands (L-arginine and L-ornithine) and assessed GLP-1 levels in circulation. We found that oral administration of both L-arginine and L-ornithine significantly increased total plasma GLP-1 levels to a similar level in GPRC6A KO and WT mice 15 minutes after gavage (both amino acids) and accumulated up to 60 minutes after gavage (L-arginine). Conversely, GLP-1 secretion at the 30- and 60-minute time points in the KO mice was attenuated and did not reach statistical significance. In summary, these data confirm that L-arginine is a potent GLP-1 secretagogue and show that the main effect occurs independently of GPRC6A. In addition, this is the first study to show that also L-ornithine powerfully elicits GLP-1 release in vivo.
[Mh] Termos MeSH primário: Aminoácidos Básicos/secreção
Peptídeo 1 Semelhante ao Glucagon/secreção
Receptores Acoplados a Proteínas-G/fisiologia
[Mh] Termos MeSH secundário: Animais
Arginina/administração & dosagem
Arginina/secreção
Peptídeo 1 Semelhante ao Glucagon/sangue
Ligantes
Masculino
Camundongos
Camundongos Endogâmicos C57BL
Camundongos Knockout
Ornitina/administração & dosagem
Ornitina/secreção
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Basic); 0 (GPRC6A protein, mouse); 0 (Ligands); 0 (Receptors, G-Protein-Coupled); 89750-14-1 (Glucagon-Like Peptide 1); 94ZLA3W45F (Arginine); E524N2IXA3 (Ornithine)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161213
[St] Status:MEDLINE
[do] DOI:10.1111/dom.12845


  9 / 252 MEDLINE  
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[PMID]:27288446
[Au] Autor:Esadze A; Chen C; Zandarashvili L; Roy S; Pettitt BM; Iwahara J
[Ad] Endereço:Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-1068, USA.
[Ti] Título:Changes in conformational dynamics of basic side chains upon protein-DNA association.
[So] Source:Nucleic Acids Res;44(14):6961-70, 2016 Aug 19.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Basic side chains play major roles in recognition of nucleic acids by proteins. However, dynamic properties of these positively charged side chains are not well understood. In this work, we studied changes in conformational dynamics of basic side chains upon protein-DNA association for the zinc-finger protein Egr-1. By nuclear magnetic resonance (NMR) spectroscopy, we characterized the dynamics of all side-chain cationic groups in the free protein and in the complex with target DNA. Our NMR order parameters indicate that the arginine guanidino groups interacting with DNA bases are strongly immobilized, forming rigid interfaces. Despite the strong short-range electrostatic interactions, the majority of the basic side chains interacting with the DNA phosphates exhibited high mobility, forming dynamic interfaces. In particular, the lysine side-chain amino groups exhibited only small changes in the order parameters upon DNA-binding. We found a similar trend in the molecular dynamics (MD) simulations for the free Egr-1 and the Egr-1-DNA complex. Using the MD trajectories, we also analyzed side-chain conformational entropy. The interfacial arginine side chains exhibited substantial entropic loss upon binding to DNA, whereas the interfacial lysine side chains showed relatively small changes in conformational entropy. These data illustrate different dynamic characteristics of the interfacial arginine and lysine side chains.
[Mh] Termos MeSH primário: Aminoácidos Básicos/metabolismo
DNA/metabolismo
Proteínas/química
Proteínas/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Cátions
DNA/química
Entropia
Seres Humanos
Simulação de Dinâmica Molecular
Ressonância Magnética Nuclear Biomolecular
Fosfatos/metabolismo
Conformação Proteica
Espectroscopia de Prótons por Ressonância Magnética
Eletricidade Estática
Dedos de Zinco
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Basic); 0 (Cations); 0 (Phosphates); 0 (Proteins); 9007-49-2 (DNA)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170605
[Lr] Data última revisão:
170605
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160612
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkw531


  10 / 252 MEDLINE  
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[PMID]:27097286
[Au] Autor:Jiang Q; Yue D; Nie Y; Xu X; He Y; Zhang S; Wagner E; Gu Z
[Ad] Endereço:National Engineering Research Center for Biomaterials, Sichuan University , Chengdu 610064, Sichuan, P. R. China.
[Ti] Título:Specially-Made Lipid-Based Assemblies for Improving Transmembrane Gene Delivery: Comparison of Basic Amino Acid Residue Rich Periphery.
[So] Source:Mol Pharm;13(6):1809-21, 2016 06 06.
[Is] ISSN:1543-8392
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Cationic lipid based assemblies provide a promising platform for effective gene condensation into nanosized particles, and the peripheral properties of the assemblies are vital for complexation and interaction with physical barriers. Here, we report three cationic twin head lipids, and each of them contains a dioleoyl-glutamate hydrophobic tail and a twin polar head of lysine, arginine, or histidine. Such lipids were proven to self-assemble in aqueous solution with well-defined nanostructures and residual amino-, guanidine-, or imidazole-rich periphery, showing strong buffering capacity and good liquidity. The assemblies with arginine (RL) or lysine (KL) periphery exhibited positive charges (∼+35 mV) and complete condensation of pDNA into nanosized complexes (∼120 nm). In contrast, assemblies composed of histidine-rich lipids (HL) showed relatively low cationic electric potential (∼+10 mV) and poor DNA binding ability. As expected, the designed RL assemblies with guanidine-rich periphery enhanced the in vitro gene transfection up to 190-fold as compared with the golden standard PEI25k and Lipofectamine 2000, especially in the presence of serum. Meanwhile, interaction with cell and endo/lysosome membrane also revealed the superiority of RL complexes, that the guanidine-rich surface efficiently promoted transmembrane process in cellular internalization and endosomal disruption. More importantly, RL complexes also succeeded beyond others in vivo with significantly (∼7-fold) enhanced expression in HepG2 tumor xenografts in mice, as well as stronger green fluorescence protein imaging in isolated tumors and tumor frozen sections.
[Mh] Termos MeSH primário: Aminoácidos Básicos/química
Aminoácidos Básicos/metabolismo
Lipídeos/química
[Mh] Termos MeSH secundário: Animais
Cátions/química
Linhagem Celular
Linhagem Celular Tumoral
DNA/metabolismo
Técnicas de Transferência de Genes
Células HEK293
Células Hep G2
Seres Humanos
Interações Hidrofóbicas e Hidrofílicas
Lipossomos/química
Camundongos
Camundongos Endogâmicos BALB C
Camundongos Nus
Tamanho da Partícula
Plasmídeos/química
Transfecção/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Amino Acids, Basic); 0 (Cations); 0 (Lipids); 0 (Lipofectamine); 0 (Liposomes); 9007-49-2 (DNA)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171121
[Lr] Data última revisão:
171121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160421
[St] Status:MEDLINE
[do] DOI:10.1021/acs.molpharmaceut.5b00967



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