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  1 / 5925 MEDLINE  
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[PMID]:29194017
[Au] Autor:Abdul Manan FM; Attan N; Widodo N; Aboul-Enein HY; Wahab RA
[Ad] Endereço:a Department of Chemistry, Faculty of Science , Universiti Teknologi Malaysia , Skudai , Malaysia.
[Ti] Título:Rhizomucor miehei lipase immobilized on reinforced chitosan-chitin nanowhiskers support for synthesis of eugenyl benzoate.
[So] Source:Prep Biochem Biotechnol;48(1):92-102, 2018 Jan 02.
[Is] ISSN:1532-2297
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:An alternative environmentally benign support was prepared from chitosan-chitin nanowhiskers (CS/CNWs) for covalent immobilization of Rhizomucor miehei lipase (RML) to increase the operational stability and recyclability of RML in synthesizing eugenyl benzoate. The CS/CNWs support and RML-CS/CNWs were characterized using X-ray diffraction, fluorescent microscopy, and Fourier transform infrared spectroscopy. Efficiency of the RML-CS/CNWs was compared to the free RML to synthesize eugenyl benzoate for parameters: reaction temperature, stirring rate, reusability, and thermal stability. Under optimal experimental conditions (50°C, 250 rpm, catalyst loading 3 mg/mL), a twofold increase in yield of eugenyl benzoate was observed for RML-CS/CNWs as compared to free RML, with the former achieving maximum yield of the ester at 62.1% after 5 hr. Results demonstrated that the strategy adopted to prepare RML-CS/CNWs was useful, producing an improved and prospectively greener biocatalyst that supported a sustainable process to prepare eugenyl benzoate. Moreover, RML-CS/CNWs are biodegradable and perform esterification reactions under ambient conditions as compared to the less eco-friendly conventional acid catalyst. This research provides a facile and promising approach for improving activity of RML in which the resultant RML-CS/CNWs demonstrated good operational stability for up to eight successive esterification cycles to synthesize eugenyl benzoate.
[Mh] Termos MeSH primário: Benzoatos/metabolismo
Quitina/química
Quitosana/química
Enzimas Imobilizadas/metabolismo
Eugenol/análogos & derivados
Lipase/metabolismo
Rhizomucor/enzimologia
[Mh] Termos MeSH secundário: Benzoatos/química
Estabilidade Enzimática
Enzimas Imobilizadas/química
Esterificação
Eugenol/metabolismo
Microbiologia Industrial
Lipase/química
Nanoestruturas/química
Rhizomucor/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Benzoates); 0 (Enzymes, Immobilized); 1398-61-4 (Chitin); 3T8H1794QW (Eugenol); 9012-76-4 (Chitosan); EC 3.1.1.3 (Lipase)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171202
[St] Status:MEDLINE
[do] DOI:10.1080/10826068.2017.1405021


  2 / 5925 MEDLINE  
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[PMID]:29335469
[Au] Autor:Aunkham A; Zahn M; Kesireddy A; Pothula KR; Schulte A; Baslé A; Kleinekathöfer U; Suginta W; van den Berg B
[Ad] Endereço:Biochemistry-Electrochemistry Research Unit, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
[Ti] Título:Structural basis for chitin acquisition by marine Vibrio species.
[So] Source:Nat Commun;9(1):220, 2018 01 15.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Chitin, an insoluble polymer of N-acetylglucosamine, is one of the most abundant biopolymers on Earth. By degrading chitin, chitinolytic bacteria such as Vibrio harveyi are critical for chitin recycling and maintenance of carbon and nitrogen cycles in the world's oceans. A decisive step in chitin degradation is the uptake of chito-oligosaccharides by an outer membrane protein channel named chitoporin (ChiP). Here, we report X-ray crystal structures of ChiP from V. harveyi in the presence and absence of chito-oligosaccharides. Structures without bound sugar reveal a trimeric assembly with an unprecedented closing of the transport pore by the N-terminus of a neighboring subunit. Substrate binding ejects the pore plug to open the transport channel. Together with molecular dynamics simulations, electrophysiology and in vitro transport assays our data provide an explanation for the exceptional affinity of ChiP for chito-oligosaccharides and point to an important role of the N-terminal gate in substrate transport.
[Mh] Termos MeSH primário: Carbono/metabolismo
Quitina/metabolismo
Nitrogênio/metabolismo
Vibrio/metabolismo
[Mh] Termos MeSH secundário: Acetilglucosamina/metabolismo
Proteínas da Membrana Bacteriana Externa/química
Proteínas da Membrana Bacteriana Externa/genética
Proteínas da Membrana Bacteriana Externa/metabolismo
Ciclo do Carbono
Cristalografia por Raios X
Modelos Moleculares
Ciclo do Nitrogênio
Oceanos e Mares
Oligossacarídeos/metabolismo
Porinas/química
Porinas/genética
Porinas/metabolismo
Conformação Proteica
Água do Mar/química
Água do Mar/microbiologia
Vibrio/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Oligosaccharides); 0 (Porins); 1398-61-4 (Chitin); 7440-44-0 (Carbon); N762921K75 (Nitrogen); V956696549 (Acetylglucosamine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180306
[Lr] Data última revisão:
180306
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02523-y


  3 / 5925 MEDLINE  
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[PMID]:28461445
[Au] Autor:Yamamoto S; Ohnishi M
[Ad] Endereço:Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan yshouji@nih.go.jp.
[Ti] Título:Glucose-Specific Enzyme IIA of the Phosphoenolpyruvate:Carbohydrate Phosphotransferase System Modulates Chitin Signaling Pathways in Vibrio cholerae.
[So] Source:J Bacteriol;199(18), 2017 09 15.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In , the genes required for chitin utilization and natural competence are governed by the chitin-responsive two-component system (TCS) sensor kinase ChiS. In the classical TCS paradigm, a sensor kinase specifically phosphorylates a cognate response regulator to activate gene expression. However, our previous genetic study suggested that ChiS stimulates the non-TCS transcriptional regulator TfoS by using mechanisms distinct from classical phosphorylation reactions (S. Yamamoto, J. Mitobe, T. Ishikawa, S. N. Wai, M. Ohnishi, H. Watanabe, and H. Izumiya, Mol Microbiol 91:326-347, 2014, https://doi.org/10.1111/mmi.12462). TfoS specifically activates the transcription of , encoding a small regulatory RNA essential for competence gene expression. Whether ChiS and TfoS interact directly remains unknown. To determine if other factors mediate the communication between ChiS and TfoS, we isolated transposon mutants that turned off :: expression but possessed intact and genes. We demonstrated an unexpected association of chitin-induced signaling pathways with the glucose-specific enzyme IIA (EIIA ) of the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) for carbohydrate uptake and catabolite control of gene expression. Genetic and physiological analyses revealed that dephosphorylated EIIA inactivated natural competence and transcription. Chitin-induced expression of the operon, which is required for chitin transport and catabolism, was also repressed by dephosphorylated EIIA Furthermore, the regulation of and expression by EIIA was dependent on ChiS and intracellular levels of ChiS were not affected by disruption of the gene encoding EIIA These results define a previously unknown connection between the PTS and chitin signaling pathways in and suggest a strategy whereby this bacterium can physiologically adapt to the existing nutrient status. The EIIA protein of the PTS coordinates a wide variety of physiological functions with carbon availability. In this report, we describe an unexpected association of chitin-activated signaling pathways in with EIIA The signaling pathways are governed by the chitin-responsive TCS sensor kinase ChiS and lead to the induction of chitin utilization and natural competence. We show that dephosphorylated EIIA inhibits both signaling pathways in a ChiS-dependent manner. This inhibition is different from classical catabolite repression that is caused by lowered levels of cyclic AMP. This work represents a newly identified connection between the PTS and chitin signaling pathways in and suggests a strategy whereby this bacterium can physiologically adapt to the existing nutrient status.
[Mh] Termos MeSH primário: Quitina/metabolismo
Regulação Bacteriana da Expressão Gênica
Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/metabolismo
Transdução de Sinais
Vibrio cholerae/genética
Vibrio cholerae/metabolismo
[Mh] Termos MeSH secundário: Elementos de DNA Transponíveis
Redes Reguladoras de Genes
Mutagênese Insercional
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA Transposable Elements); 1398-61-4 (Chitin); EC 2.7.1.- (Phosphoenolpyruvate Sugar Phosphotransferase System)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:180306
[Lr] Data última revisão:
180306
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE


  4 / 5925 MEDLINE  
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[PMID]:29478637
[Au] Autor:Gurtowski LA; Griggs CS; Gude VG; Shukla MK
[Ad] Endereço:Environmental Laboratory, Engineer Research and Development Center, Vicksburg, MS 39180, USA.
[Ti] Título:An integrated theoretical and experimental investigation of insensitive munition compounds adsorption on cellulose, cellulose triacetate, chitin and chitosan surfaces.
[So] Source:J Environ Sci (China);64:174-180, 2018 Feb.
[Is] ISSN:1001-0742
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:This manuscript reports results of combined computational chemistry and batch adsorption investigation of insensitive munition compounds, 2,4-dinitroanisole (DNAN), triaminotrinitrobenzene (TATB), 1,1-diamino-2,2-dinitroethene (FOX-7) and nitroguanidine (NQ), and traditional munition compound 2,4,6-trinitrotoluene (TNT) on the surfaces of cellulose, cellulose triacetate, chitin and chitosan biopolymers. Cellulose, cellulose triacetate, chitin and chitosan were modeled as trimeric form of the linear chain of C chair conformation of ß-d-glucopyranos, its triacetate form, ß-N-acetylglucosamine and D-glucosamine, respectively, in the 1âž”4 linkage. Geometries were optimized at the M062X functional level of the density functional theory (DFT) using the 6-31G(d,p) basis set in the gas phase and in the bulk water solution using the conductor-like polarizable continuum model (CPCM) approach. The nature of potential energy surfaces of the optimized geometries were ascertained through the harmonic vibrational frequency analysis. The basis set superposition error (BSSE) corrected interaction energies were obtained using the 6-311G(d,p) basis set at the same theoretical level. The computed BSSE in the gas phase was used to correct interaction energy in the bulk water solution. Computed and experimental results regarding the ability of considered surfaces in adsorbing the insensitive munitions compounds are discussed.
[Mh] Termos MeSH primário: Substâncias Explosivas/química
Modelos Químicos
[Mh] Termos MeSH secundário: Adsorção
Anisóis/química
Celulose/análogos & derivados
Celulose/química
Quitina/química
Quitosana/química
Guanidinas/química
Nitrocompostos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (1,1-diamino-2,2-dinitroethene); 0 (Anisoles); 0 (Explosive Agents); 0 (Guanidines); 0 (Nitro Compounds); 1398-61-4 (Chitin); 1L0OD70295 (2,4-dinitroanisole); 9004-34-6 (Cellulose); 9012-09-3 (cellulose triacetate); 9012-76-4 (Chitosan); NAY6KWL67F (nitroguanidine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180227
[St] Status:MEDLINE


  5 / 5925 MEDLINE  
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[PMID]:28456077
[Au] Autor:Zhao Y; Wang Y; Gong J; Yang L; Niu C; Ni X; Wang Y; Peng S; Gu X; Sun C; Yang Y
[Ad] Endereço:Key Laboratory of Neuroregeneration, Nantong University, Nantong 226007, PR China; Co-innovation Center of Neuroregeneration, Jiangsu Province, Nantong 226007, PR China.
[Ti] Título:Chitosan degradation products facilitate peripheral nerve regeneration by improving macrophage-constructed microenvironments.
[So] Source:Biomaterials;134:64-77, 2017 Jul.
[Is] ISSN:1878-5905
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Chitosan-based artificial nerve grafts have been widely employed to repair peripheral nerve defects. Our previous study has shown that chitosan constructed nerve graft not only provides suitable scaffolds for nerve regeneration, its degradation products, chitooligosaccharides (COS), also promote nerve repair. However, the involved mechanisms are still not fully elucidated. In the present study, we observed that pro-inflammatory cytokines, as well as macrophage infiltration, were transiently up-regulated in the injured sciatic nerves which were bridged with silicon tubes filled with COS. Based upon transcriptome analysis, the axis of miR-327/CCL2 in Schwann cells (SCs) was identified as a potential target of COS. The following experiments have confirmed that COS stimulate CCL2 expression by down-regulating miR-327 in SCs. Consequently, the resulting CCL2 induces macrophage migration at injury sites to re-construct microenvironments and thus facilitates nerve regeneration. Collectively, our data provide a theoretical basis for the clinical application of chitosan-based grafts in peripheral nerve regeneration.
[Mh] Termos MeSH primário: Quitosana/química
Quitosana/farmacologia
Macrófagos/efeitos dos fármacos
Macrófagos/metabolismo
Regeneração Nervosa/efeitos dos fármacos
Nervos Periféricos/citologia
Nervos Periféricos/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Proliferação Celular/efeitos dos fármacos
Quitina/análogos & derivados
Quitina/química
Quitina/farmacologia
Cromatografia Líquida de Alta Pressão
Biologia Computacional
Ensaio de Imunoadsorção Enzimática
Células HEK293
Seres Humanos
Imuno-Histoquímica
Hibridização In Situ
Masculino
Camundongos
Células RAW 264.7
Ratos
Ratos Sprague-Dawley
Reação em Cadeia da Polimerase em Tempo Real
Células de Schwann/efeitos dos fármacos
Células de Schwann/metabolismo
Cicatrização/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (oligochitosan); 1398-61-4 (Chitin); 9012-76-4 (Chitosan)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170430
[St] Status:MEDLINE


  6 / 5925 MEDLINE  
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[PMID]:28468279
[Au] Autor:Terfrüchte M; Reindl M; Jankowski S; Sarkari P; Feldbrügge M; Schipper K
[Ad] Endereço:Institute for Microbiology, Cluster for Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, 40204 Düsseldorf, Germany. marius.terfruechte@hhu.de.
[Ti] Título:Applying Unconventional Secretion in Ustilago maydis for the Export of Functional Nanobodies.
[So] Source:Int J Mol Sci;18(5), 2017 Apr 29.
[Is] ISSN:1422-0067
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Exploiting secretory pathways for production of heterologous proteins is highly advantageous with respect to efficient downstream processing. In eukaryotic systems the vast majority of heterologous proteins for biotechnological application is exported via the canonical endoplasmic reticulum-Golgi pathway. In the endomembrane system target proteins are often glycosylated and may thus be modified with foreign glycan patterns. This can be destructive for their activity or cause immune reactions against therapeutic proteins. Hence, using unconventional secretion for protein expression is an attractive alternative. In the fungal model , chitinase Cts1 is secreted via an unconventional pathway connected to cell separation which can be used to co-export heterologous proteins. Here, we apply this mechanism for the production of nanobodies. First, we achieved expression and unconventional secretion of a functional nanobody directed against green fluorescent protein (Gfp). Second, we found that Cts1 binds to chitin and that this feature can be applied to generate a Gfp-trap. Thus, we demonstrated the dual use of Cts1 serving both as export vehicle and as purification tag. Finally, we established and optimized the production of a nanobody against botulinum toxin A and hence describe the first pharmaceutically relevant target exported by Cts1-mediated unconventional secretion.
[Mh] Termos MeSH primário: Quitinases/metabolismo
Proteínas Fúngicas/metabolismo
Anticorpos de Domínio Único/metabolismo
Ustilago/metabolismo
[Mh] Termos MeSH secundário: Toxinas Botulínicas Tipo A/imunologia
Quitina/metabolismo
Clonagem Molecular
Proteínas de Fluorescência Verde/imunologia
Microbiologia Industrial
Transporte Proteico
Proteínas Recombinantes/genética
Proteínas Recombinantes/imunologia
Proteínas Recombinantes/metabolismo
Anticorpos de Domínio Único/genética
Anticorpos de Domínio Único/imunologia
Ustilago/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fungal Proteins); 0 (Recombinant Proteins); 0 (Single-Domain Antibodies); 1398-61-4 (Chitin); 147336-22-9 (Green Fluorescent Proteins); EC 3.2.1.14 (Chitinases); EC 3.4.24.69 (Botulinum Toxins, Type A)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180221
[Lr] Data última revisão:
180221
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE


  7 / 5925 MEDLINE  
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[PMID]:29283261
[Au] Autor:Xu J; Liu S; Chen G; Chen T; Song T; Wu J; Shi C; He M; Tian J
[Ad] Endereço:State Key Laboratory of Pulp and Paper Engineering, School of Light Industry and Engineering and ‡School of Medicine, South China University of Technology , Guangzhou 510640, P. R. China.
[Ti] Título:Engineering Biocompatible Hydrogels from Bicomponent Natural Nanofibers for Anticancer Drug Delivery.
[So] Source:J Agric Food Chem;66(4):935-942, 2018 Jan 31.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Natural hydrogels have attracted extensive research interest and shown great potential for many biomedical applications. In this study, a series of biocompatible hydrogels was reported based on the self-assembly of positively charged partially deacetylated α-chitin nanofibers (α-DECHN) and negatively charged 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibers (TOCNF) for anticancer drug delivery. The formation mechanisms of the α-DECHN/TOCNF hydrogels with different mixing proportions were studied, and their morphological, mechanical, and swelling properties were comprehensively investigated. Additionally, the drug delivery performance of the hydrogels was compared via sustained release test of an anticancer drug (5-fluorouracil). The results showed that the hydrogel with higher physical cross-linking degree exhibited a higher drug loading efficiency and drug release percentage.
[Mh] Termos MeSH primário: Antineoplásicos/administração & dosagem
Materiais Biocompatíveis
Quitina/química
Óxidos N-Cíclicos/química
Sistemas de Liberação de Medicamentos
Nanofibras/química
[Mh] Termos MeSH secundário: Celulose/química
Reagentes para Ligações Cruzadas
Preparações de Ação Retardada
Fluoruracila/administração & dosagem
Hidrogéis
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antineoplastic Agents); 0 (Biocompatible Materials); 0 (Cross-Linking Reagents); 0 (Cyclic N-Oxides); 0 (Delayed-Action Preparations); 0 (Hydrogels); 1398-61-4 (Chitin); 9004-34-6 (Cellulose); U3P01618RT (Fluorouracil); VQN7359ICQ (TEMPO)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171229
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b04210


  8 / 5925 MEDLINE  
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[PMID]:27777036
[Au] Autor:Salgado-Lugo H; Sánchez-Arreguín A; Ruiz-Herrera J
[Ad] Endereço:Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Gto., Mexico.
[Ti] Título:Heterologous expression of an active chitin synthase from Rhizopus oryzae.
[So] Source:Fungal Genet Biol;97:10-17, 2016 12.
[Is] ISSN:1096-0937
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Chitin synthases are highly important enzymes in nature, where they synthesize structural components in species belonging to different eukaryotic kingdoms, including kingdom Fungi. Unfortunately, their structure and the molecular mechanism of synthesis of their microfibrilar product remain largely unknown, probably because no fungal active chitin synthases have been isolated, possibly due to their extreme hydrophobicity. In this study we have turned to the heterologous expression of the transcript from a small chitin synthase of Rhizopus oryzae (RO3G_00942, Chs1) in Escherichia coli. The enzyme was active, but accumulated mostly in inclusion bodies. High concentrations of arginine or urea solubilized the enzyme, but their dilution led to its denaturation and precipitation. Nevertheless, use of urea permitted the purification of small amounts of the enzyme. The properties of Chs1 (Km, optimum temperature and pH, effect of GlcNAc) were abnormal, probably because it lacks the hydrophobic transmembrane regions characteristic of chitin synthases. The product of the enzyme showed that, contrasting with chitin made by membrane-bound Chs's and chitosomes, was only partially in the form of short microfibrils of low crystallinity. This approach may lead to future developments to obtain active chitin synthases that permit understanding their molecular mechanism of activity, and microfibril assembly.
[Mh] Termos MeSH primário: Quitina Sintase/biossíntese
Quitina/biossíntese
Rhizopus/enzimologia
[Mh] Termos MeSH secundário: Arginina/química
Quitina/genética
Quitina Sintase/genética
Escherichia coli/genética
Regulação Fúngica da Expressão Gênica
Rhizopus/genética
Ureia/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
1398-61-4 (Chitin); 8W8T17847W (Urea); 94ZLA3W45F (Arginine); EC 2.4.1.16 (Chitin Synthase)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171214
[Lr] Data última revisão:
171214
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161030
[St] Status:MEDLINE


  9 / 5925 MEDLINE  
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[PMID]:27777382
[Au] Autor:Yu S; Lee E; Tsogbadrakh B; Son GI; Kim M
[Ad] Endereço:Department of Preventive Medicine, College of Medicine, Korea University, Seoul, 136-701, Republic of Korea.
[Ti] Título:Prenatal hyperbaric normoxia treatment improves healthspan and regulates chitin metabolic genes in .
[So] Source:Aging (Albany NY);8(10):2538-2550, 2016 Oct 24.
[Is] ISSN:1945-4589
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Aging is a universal, irreversible process accompanied by physiological declines that culminate in death. Rapid progress in gerontology research has revealed that aging can be slowed through mild stress-induced hormesis. We previously reported that hyperbaric normoxia (HN, 2 atm absolute pressure with 10% O ) induces a cytoprotective response by regulating fibronectin. In the present study, we investigated the hormetic effects of prenatal HN exposure on healthspan related to molecular defense mechanisms. HN exposure had no disruptive effect on developmental rate or adult body weight. However, lifespan was clearly enhanced, as was resistance to oxidative and heat stress. In addition, levels of reactive oxygen species were significantly decreased and motor performance was increased. HN stress has been shown to trigger molecular changes in the heat shock response and ROS scavenging system, including , and . Furthermore, to determine the hormetic mechanism underlying these phenotypic and molecular changes, we performed a genome-wide profiling in HN-exposed and control flies. Genes encoding chitin metabolism were highly up-regulated, which could possibly serve to scavenge free radicals. These results identify prenatal HN exposure as a potential hormetic factor that may improve longevity and healthspan by enhancing defense mechanisms in .
[Mh] Termos MeSH primário: Envelhecimento/genética
Quitina/genética
Longevidade/fisiologia
Estresse Fisiológico/fisiologia
[Mh] Termos MeSH secundário: Envelhecimento/metabolismo
Animais
Quitina/metabolismo
Drosophila melanogaster
Feminino
Regulação da Expressão Gênica
Proteínas de Choque Térmico HSP70/metabolismo
Resposta ao Choque Térmico/fisiologia
Estresse Oxidativo/fisiologia
Gravidez
Espécies Reativas de Oxigênio/metabolismo
Superóxido Dismutase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (HSP70 Heat-Shock Proteins); 0 (Reactive Oxygen Species); 1398-61-4 (Chitin); EC 1.15.1.1 (Superoxide Dismutase)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161026
[St] Status:MEDLINE
[do] DOI:10.18632/aging.101084


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[PMID]:28973025
[Au] Autor:Poncini L; Wyrsch I; Dénervaud Tendon V; Vorley T; Boller T; Geldner N; Métraux JP; Lehmann S
[Ad] Endereço:Department of Biology, University of Fribourg, Fribourg, Switzerland.
[Ti] Título:In roots of Arabidopsis thaliana, the damage-associated molecular pattern AtPep1 is a stronger elicitor of immune signalling than flg22 or the chitin heptamer.
[So] Source:PLoS One;12(10):e0185808, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Plants interpret their immediate environment through perception of small molecules. Microbe-associated molecular patterns (MAMPs) such as flagellin and chitin are likely to be more abundant in the rhizosphere than plant-derived damage-associated molecular patterns (DAMPs). We investigated how the Arabidopsis thaliana root interprets MAMPs and DAMPs as danger signals. We monitored root development during exposure to increasing concentrations of the MAMPs flg22 and the chitin heptamer as well as of the DAMP AtPep1. The tissue-specific expression of defence-related genes in roots was analysed using a toolkit of promoter::YFPN lines reporting jasmonic acid (JA)-, salicylic acid (SA)-, ethylene (ET)- and reactive oxygen species (ROS)- dependent signalling. Finally, marker responses were analysed during invasion by the root pathogen Fusarium oxysporum. The DAMP AtPep1 triggered a stronger activation of the defence markers compared to flg22 and the chitin heptamer. In contrast to the tested MAMPs, AtPep1 induced SA- and JA-signalling markers in the root and caused a severe inhibition of root growth. Fungal attack resulted in a strong activation of defence genes in tissues close to the invading fungal hyphae. The results collectively suggest that AtPep1 presents a stronger danger signal to the Arabidopsis root than the MAMPs flg22 and chitin heptamer.
[Mh] Termos MeSH primário: Proteínas de Arabidopsis/metabolismo
Quitina/metabolismo
Flagelina/metabolismo
Raízes de Plantas/metabolismo
Transdução de Sinais/fisiologia
Transativadores/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Arabidopsis/genética
Quitina/genética
Ciclopentanos/metabolismo
Etilenos/metabolismo
Flagelina/genética
Regulação da Expressão Gênica de Plantas
Oxilipinas/metabolismo
Raízes de Plantas/crescimento & desenvolvimento
Espécies Reativas de Oxigênio/metabolismo
Ácido Salicílico/metabolismo
Transativadores/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Arabidopsis Proteins); 0 (Cyclopentanes); 0 (Ethylenes); 0 (Oxylipins); 0 (Pep1 protein, Arabidopsis); 0 (Reactive Oxygen Species); 0 (Trans-Activators); 12777-81-0 (Flagellin); 1398-61-4 (Chitin); 6RI5N05OWW (jasmonic acid); 91GW059KN7 (ethylene); O414PZ4LPZ (Salicylic Acid)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171004
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185808



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