Base de dados : MEDLINE
Pesquisa : D08.811.520.241.700 [Categoria DeCS]
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  1 / 1926 MEDLINE  
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[PMID]:28455404
[Au] Autor:Leng Y; Yang Y; Ren D; Huang L; Dai L; Wang Y; Chen L; Tu Z; Gao Y; Li X; Zhu L; Hu J; Zhang G; Gao Z; Guo L; Kong Z; Lin Y; Qian Q; Zeng D
[Ad] Endereço:State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou 310006, China (Yu.L., Y.Y., D.R., L.H., L.D., Y.W., L.C., Z.T., Y.G., L.Z., J.H., G.Z., Z.G., L.G., Q.Q., D.Z.).
[Ti] Título:A Rice Gene Is Required for Plant Growth and Leaf Senescence.
[So] Source:Plant Physiol;174(2):1151-1166, 2017 Jun.
[Is] ISSN:1532-2548
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:To better understand the molecular mechanisms behind plant growth and leaf senescence in monocot plants, we identified a mutant exhibiting dwarfism and an early-senescence leaf phenotype, termed ( ). Histological analysis showed that the abnormal growth was caused by a reduction in cell number. Further investigation revealed that the decline in cell number in was affected by the cell cycle. Physiological analysis, transmission electron microscopy, and TUNEL assays showed that leaf senescence was triggered by the accumulation of reactive oxygen species. The gene was cloned using a map-based approach. It was shown to encode a pectate lyase (PEL) precursor that contains a PelC domain. contains all the conserved residues of PEL and has strong similarity with plant PelC. is expressed in all tissues but predominantly in elongating tissues. Functional analysis revealed that mutation of decreased the total PEL enzymatic activity, increased the degree of methylesterified homogalacturonan, and altered the cell wall composition and structure. In addition, transcriptome assay revealed that a set of cell wall function- and senescence-related gene expression was altered in plants. Our research indicates that is involved in both the maintenance of normal cell division and the induction of leaf senescence. These findings reveal a new molecular mechanism for plant growth and leaf senescence mediated by genes.
[Mh] Termos MeSH primário: Genes de Plantas
Oryza/enzimologia
Oryza/genética
Desenvolvimento Vegetal/genética
Folhas de Planta/crescimento & desenvolvimento
Polissacarídeo-Liase/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Contagem de Células
Ciclo Celular/genética
Morte Celular/genética
Parede Celular/metabolismo
Clonagem Molecular
Esterificação
Perfilação da Expressão Gênica
Regulação da Expressão Gênica de Plantas
Modelos Biológicos
Mutação/genética
Oryza/crescimento & desenvolvimento
Pectinas/metabolismo
Fenótipo
Filogenia
Folhas de Planta/genética
Folhas de Planta/ultraestrutura
Polissacarídeo-Liase/química
Polissacarídeo-Liase/metabolismo
Espécies Reativas de Oxigênio/metabolismo
Transcriptoma/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Pectins); 0 (Reactive Oxygen Species); EC 4.2.2.- (Polysaccharide-Lyases); EC 4.2.2.2 (pectate lyase); VV3XD4CL04 (polygalacturonic acid)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180115
[Lr] Data última revisão:
180115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170430
[St] Status:MEDLINE
[do] DOI:10.1104/pp.16.01625


  2 / 1926 MEDLINE  
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[PMID]:28851327
[Au] Autor:Kim CS; Jo K; Kim JS; Pyo MK; Kim J
[Ad] Endereço:Korean Medicine Convergence Research Division, Korea Institute of Oriental Medicine (KIOM), 1672 Yuseongdaero, Yuseong-gu, Daejeon, 34054, South Korea.
[Ti] Título:GS-E3D, a new pectin lyase-modified red ginseng extract, inhibited diabetes-related renal dysfunction in streptozotocin-induced diabetic rats.
[So] Source:BMC Complement Altern Med;17(1):430, 2017 Aug 29.
[Is] ISSN:1472-6882
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: GS-E3D is a newly developed pectin lyase-modified red ginseng extract. The purpose of this study was to investigate the therapeutic effects of GS-E3D on diabetes-related renal dysfunction in streptozotocin-induced diabetic rats. METHOD: GS-E3D (25, 50, and 100 mg/kg body weight per day) was administered for 6 weeks. The levels of blood glucose and hemoglobin A1c, and of urinary albumin, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and advanced glycation end-products (AGEs) were determined. Kidney histopathology, renal accumulation of AGEs, and expression of α-smooth muscle actin (α-SMA) were also examined. RESULTS: Administration of GS-E3D for 6 weeks reduced urinary levels of albumin, 8-OHdG, and AGEs in diabetic rats. Mesangial expansion, renal accumulation of AGEs, and enhanced α-SMA expression were significantly inhibited by GS-E3D treatment. Oral administration of GS-E3D dose-dependently improved all symptoms of diabetic nephropathy by inhibiting renal accumulation of AGEs and oxidative stress. CONCLUSION: The results of this study indicate that the use of GS-E3D as a food supplement may provide effective treatment of diabetes-induced renal dysfunction.
[Mh] Termos MeSH primário: Diabetes Mellitus Experimental/complicações
Nefropatias Diabéticas/tratamento farmacológico
Panax/química
Extratos Vegetais/administração & dosagem
[Mh] Termos MeSH secundário: Animais
Diabetes Mellitus Experimental/fisiopatologia
Nefropatias Diabéticas/etiologia
Nefropatias Diabéticas/metabolismo
Nefropatias Diabéticas/fisiopatologia
Produtos Finais de Glicação Avançada/metabolismo
Seres Humanos
Rim/efeitos dos fármacos
Rim/metabolismo
Masculino
Estresse Oxidativo
Extratos Vegetais/química
Polissacarídeo-Liase/química
Ratos
Ratos Sprague-Dawley
Estreptozocina/efeitos adversos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Glycation End Products, Advanced); 0 (Plant Extracts); 5W494URQ81 (Streptozocin); EC 4.2.2.- (Polysaccharide-Lyases); EC 4.2.2.10 (pectin lyase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170831
[St] Status:MEDLINE
[do] DOI:10.1186/s12906-017-1925-7


  3 / 1926 MEDLINE  
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[PMID]:28684315
[Au] Autor:He C; Ohnishi K
[Ad] Endereço:The United Graduate School of Agricultural Sciences, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan.
[Ti] Título:Efficient renaturation of inclusion body proteins denatured by SDS.
[So] Source:Biochem Biophys Res Commun;490(4):1250-1253, 2017 Sep 02.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Inclusion bodies are often formed when the foreign protein is over expressed in Escherichia coli. Since proteins in inclusion bodies are inactive, denaturing and refolding of inclusion body proteins are necessary to obtain the active form. Instead of the conventional denaturants, urea and guanidine hydrochloride, a strong anionic detergent SDS was used to solubilize C-terminal His-tag form of ulvan lyase in the inclusion bodies. Solution containing SDS-solubilized enzyme were kept on ice to precipitate SDS, followed by SDS-KCl insoluble crystal formation to remove SDS completely. After removing the precipitate by centrifugation, the supernatant was applied to Ni-NTA column to purify His-tagged ulvan lyase. The purified protein showed a dimeric form and ulvan lyase activity, demonstrating that SDS-denatured protein was renatured and recovered enzyme activity. This simple method could be useful for refolding other inclusion body proteins.
[Mh] Termos MeSH primário: Detergentes/farmacologia
Corpos de Inclusão/enzimologia
Polissacarídeo-Liase/metabolismo
Dodecilsulfato de Sódio/farmacologia
[Mh] Termos MeSH secundário: Escherichia coli/efeitos dos fármacos
Polissacarídeo-Liase/genética
Desnaturação Proteica/efeitos dos fármacos
Fatores de Tempo
Ulva/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Detergents); 368GB5141J (Sodium Dodecyl Sulfate); EC 4.2.2.- (Polysaccharide-Lyases)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170921
[Lr] Data última revisão:
170921
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170708
[St] Status:MEDLINE


  4 / 1926 MEDLINE  
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[PMID]:28637865
[Au] Autor:Munoz-Munoz J; Cartmell A; Terrapon N; Baslé A; Henrissat B; Gilbert HJ
[Ad] Endereço:From the Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom.
[Ti] Título:An evolutionarily distinct family of polysaccharide lyases removes rhamnose capping of complex arabinogalactan proteins.
[So] Source:J Biol Chem;292(32):13271-13283, 2017 Aug 11.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The human gut microbiota utilizes complex carbohydrates as major nutrients. The requirement for efficient glycan degrading systems exerts a major selection pressure on this microbial community. Thus, we propose that this microbial ecosystem represents a substantial resource for discovering novel carbohydrate active enzymes. To test this hypothesis we screened the potential enzymatic functions of hypothetical proteins encoded by genes of that were up-regulated by arabinogalactan proteins or AGPs. Although AGPs are ubiquitous in plants, there is a paucity of information on their detailed structure, the function of these glycans , and the mechanisms by which they are depolymerized in microbial ecosystems. Here we have discovered a new polysaccharide lyase family that is specific for the l-rhamnose-α1,4-d-glucuronic acid linkage that caps the side chains of complex AGPs. The reaction product generated by the lyase, Δ4,5-unsaturated uronic acid, is removed from AGP by a glycoside hydrolase located in family GH105, producing the final product 4-deoxy-ß-l-threo-hex-4-enepyranosyl-uronic acid. The crystal structure of a member of the novel lyase family revealed a catalytic domain that displays an (α/α) barrel-fold. In the center of the barrel is a deep pocket, which, based on mutagenesis data and amino acid conservation, comprises the active site of the lyase. A tyrosine is the proposed catalytic base in the ß-elimination reaction. This study illustrates how highly complex glycans can be used as a scaffold to discover new enzyme families within microbial ecosystems where carbohydrate metabolism is a major evolutionary driver.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Bacteroides thetaiotaomicron/enzimologia
Loci Gênicos
Modelos Moleculares
Mucoproteínas/metabolismo
Polissacarídeo-Liase/metabolismo
Ramnose/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Biocatálise
Domínio Catalítico
Sequência Conservada
Cristalografia por Raios X
Bases de Dados de Proteínas
Hidrólise
Isoenzimas
Cinética
Filogenia
Proteínas de Plantas/metabolismo
Polissacarídeo-Liase/química
Polissacarídeo-Liase/genética
Conformação Proteica
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
Estereoisomerismo
Especificidade por Substrato
Tirosina
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Isoenzymes); 0 (Mucoproteins); 0 (Plant Proteins); 0 (Recombinant Proteins); 0 (arabinogalactan proteins); 42HK56048U (Tyrosine); EC 4.2.2.- (Polysaccharide-Lyases); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170825
[Lr] Data última revisão:
170825
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170623
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.794578


  5 / 1926 MEDLINE  
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[PMID]:28592491
[Au] Autor:Badur AH; Plutz MJ; Yalamanchili G; Jagtap SS; Schweder T; Unfried F; Markert S; Polz MF; Hehemann JH; Rao CV
[Ad] Endereço:From the Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801.
[Ti] Título:Exploiting fine-scale genetic and physiological variation of closely related microbes to reveal unknown enzyme functions.
[So] Source:J Biol Chem;292(31):13056-13067, 2017 Aug 04.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Polysaccharide degradation by marine microbes represents one of the largest and most rapid heterotrophic transformations of organic matter in the environment. Microbes employ systems of complementary carbohydrate-specific enzymes to deconstruct algal or plant polysaccharides (glycans) into monosaccharides. Because of the high diversity of glycan substrates, the functions of these enzymes are often difficult to establish. One solution to this problem may lie within naturally occurring microdiversity; varying numbers of enzymes, due to gene loss, duplication, or transfer, among closely related environmental microbes create metabolic differences akin to those generated by knock-out strains engineered in the laboratory used to establish the functions of unknown genes. Inspired by this natural fine-scale microbial diversity, we show here that it can be used to develop hypotheses guiding biochemical experiments for establishing the role of these enzymes in nature. In this work, we investigated alginate degradation among closely related strains of the marine bacterium One strain, 13B01, exhibited high extracellular alginate lyase activity compared with other strains. To identify the enzymes responsible for this high extracellular activity, we compared 13B01 with the previously characterized 12B01, which has low extracellular activity and lacks two alginate lyase genes present in 13B01. Using a combination of genomics, proteomics, biochemical, and functional screening, we identified a polysaccharide lyase family 7 enzyme that is unique to 13B01, secreted, and responsible for the rapid digestion of extracellular alginate. These results demonstrate the value of querying the enzymatic repertoires of closely related microbes to rapidly pinpoint key proteins with beneficial functions.
[Mh] Termos MeSH primário: Alginatos/metabolismo
Organismos Aquáticos/fisiologia
Proteínas de Bactérias/metabolismo
Polissacarídeo-Liase/metabolismo
Vibrio/fisiologia
[Mh] Termos MeSH secundário: Alginatos/química
Organismos Aquáticos/enzimologia
Organismos Aquáticos/crescimento & desenvolvimento
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Proteínas de Bactérias/secreção
Biomarcadores/metabolismo
Cristalografia por Raios X
Regulação Bacteriana da Expressão Gênica
Técnicas de Inativação de Genes
Genômica/métodos
Ácido Glucurônico/química
Ácido Glucurônico/metabolismo
Ácidos Hexurônicos/química
Ácidos Hexurônicos/metabolismo
Concentração de Íons de Hidrogênio
Hidrólise
Isoenzimas/genética
Isoenzimas/isolamento & purificação
Isoenzimas/metabolismo
Isoenzimas/secreção
Estrutura Molecular
Peso Molecular
Filogenia
Polissacarídeo-Liase/química
Polissacarídeo-Liase/genética
Polissacarídeo-Liase/secreção
Proteômica/métodos
Proteínas Recombinantes/isolamento & purificação
Proteínas Recombinantes/metabolismo
Especificidade da Espécie
Especificidade por Substrato
Vibrio/enzimologia
Vibrio/crescimento & desenvolvimento
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alginates); 0 (Bacterial Proteins); 0 (Biomarkers); 0 (Hexuronic Acids); 0 (Isoenzymes); 0 (Recombinant Proteins); 8A5D83Q4RW (Glucuronic Acid); 8C3Z4148WZ (alginic acid); EC 4.2.2.- (Polysaccharide-Lyases); EC 4.2.2.3 (poly(beta-D-mannuronate) lyase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170825
[Lr] Data última revisão:
170825
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170609
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.787192


  6 / 1926 MEDLINE  
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[PMID]:28417359
[Au] Autor:Jones DR; McLean R; Abbott DW
[Ad] Endereço:Functional Genomics of Complex Carbohydrate Utilization, Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, 5403 1st Ave. South, Lethbridge, T1J 4B1, AB, Canada.
[Ti] Título:An Improved Kinetic Assay for the Characterization of Metal-Dependent Pectate Lyases.
[So] Source:Methods Mol Biol;1588:37-44, 2017.
[Is] ISSN:1940-6029
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Pectate lyases are a subset of polysaccharide lyases (PLs) that specifically utilize a metal dependent ß-elimination mechanism to cleave glyosidic bonds in homogalacturonan (HG; α-D-1,4-galacturonic acid). Most commonly, PLs harness calcium for catalysis; however, some PL families (e.g., PL2 and PL22) display preferences for transitional metals. Deploying alternative metals during ß-elimination is correlated with signature coordination pocket chemistry, and is reflective of the evolution, functional specialization, and cellular location of PL activity. Here we describe an optimized method for the analysis of metal-dependent polysaccharide lyases (PLs). We use an endolytic PL2 from Yersinia enterocolitica (YePL2A) as example to demonstrate how altering the catalytic metal within the reaction can modulate PL kinetics.
[Mh] Termos MeSH primário: Ensaios Enzimáticos/métodos
Polissacarídeo-Liase/química
[Mh] Termos MeSH secundário: Parede Celular/química
Ácidos Hexurônicos/química
Cinética
Células Vegetais/química
Polissacarídeo-Liase/metabolismo
Yersinia enterocolitica/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hexuronic Acids); 0 (hexenuronic acid); EC 4.2.2.- (Polysaccharide-Lyases); EC 4.2.2.2 (pectate lyase)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170421
[Lr] Data última revisão:
170421
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170419
[St] Status:MEDLINE
[do] DOI:10.1007/978-1-4939-6899-2_4


  7 / 1926 MEDLINE  
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[PMID]:28342877
[Au] Autor:Suzuki T; Kanamori T; Inouye S
[Ad] Endereço:Department of Biochemistry, School of Dentistry, Aichi-Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan. Electronic address: tsuzuki@dpc.agu.ac.jp.
[Ti] Título:Quantitative visualization of synchronized insulin secretion from 3D-cultured cells.
[So] Source:Biochem Biophys Res Commun;486(4):886-892, 2017 May 13.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Quantitative visualization of synchronized insulin secretion was performed in an isolated rat pancreatic islet and a spheroid of rat pancreatic beta cell line using a method of video-rate bioluminescence imaging. Video-rate images of insulin secretion from 3D-cultured cells were obtained by expressing the fusion protein of insulin and Gaussia luciferase (Insulin-GLase). A subclonal rat INS-1E cell line stably expressing Insulin-GLase, named iGL, was established and a cluster of iGL cells showed oscillatory insulin secretion that was completely synchronized in response to high glucose. Furthermore, we demonstrated the effect of an antidiabetic drug, glibenclamide, on synchronized insulin secretion from 2D- and 3D-cultured iGL cells. The amount of secreted Insulin-GLase from iGL cells was also determined by a luminometer. Thus, our bioluminescence imaging method could generally be used for investigating protein secretion from living 3D-cultured cells. In addition, iGL cell line would be valuable for evaluating antidiabetic drugs.
[Mh] Termos MeSH primário: Células Secretoras de Insulina/citologia
Células Secretoras de Insulina/secreção
Insulina/secreção
Ilhotas Pancreáticas/citologia
Ilhotas Pancreáticas/metabolismo
Imagem Molecular/métodos
[Mh] Termos MeSH secundário: Animais
Linhagem Celular
Células Cultivadas
Genes Reporter/genética
Polissacarídeo-Liase/genética
Polissacarídeo-Liase/metabolismo
Impressão Tridimensional
Ratos
Ratos Wistar
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Insulin); EC 4.2.2.- (Polysaccharide-Lyases); EC 4.2.2.13 (alpha-1,4-glucan lyase)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170619
[Lr] Data última revisão:
170619
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170327
[St] Status:MEDLINE


  8 / 1926 MEDLINE  
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[PMID]:28290654
[Au] Autor:Ulaganathan T; Boniecki MT; Foran E; Buravenkov V; Mizrachi N; Banin E; Helbert W; Cygler M
[Ad] Endereço:Department of Biochemistry, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5E5, Canada.
[Ti] Título:New Ulvan-Degrading Polysaccharide Lyase Family: Structure and Catalytic Mechanism Suggests Convergent Evolution of Active Site Architecture.
[So] Source:ACS Chem Biol;12(5):1269-1280, 2017 May 19.
[Is] ISSN:1554-8937
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Ulvan is a complex sulfated polysaccharide biosynthesized by green seaweed and contains predominantly rhamnose, xylose, and uronic acid sugars. Ulvan-degrading enzymes have only recently been identified and added to the CAZy ( www.cazy.org ) database as family PL24, but neither their structure nor catalytic mechanism(s) are yet known. Several homologous, new ulvan lyases, have been discovered in Pseudoalteromonas sp. strain PLSV, Alteromonas LOR, and Nonlabens ulvanivorans, defining a new family PL25, with the lyase encoded by the gene PLSV_3936 being one of them. This enzyme cleaves the glycosidic bond between 3-sulfated rhamnose (R3S) and glucuronic acid (GlcA) or iduronic acid (IdoA) via a ß-elimination mechanism. We report the crystal structure of PLSV_3936 and its complex with a tetrasaccharide substrate. PLSV_3936 folds into a seven-bladed ß-propeller, with each blade consisting of four antiparallel ß-strands. Sequence conservation analysis identified a highly conserved region lining at one end of a deep crevice on the protein surface. The putative active site was identified by mutagenesis and activity measurements. Crystal structure of the enzyme with a bound tetrasaccharide substrate confirmed the identity of base and acid residues and allowed determination of the catalytic mechanism and also the identification of residues neutralizing the uronic acid carboxylic group. The PLSV_3936 structure provides an example of a convergent evolution among polysaccharide lyases toward a common active site architecture embedded in distinct folds.
[Mh] Termos MeSH primário: Domínio Catalítico
Evolução Molecular
Polissacarídeo-Liase/química
[Mh] Termos MeSH secundário: Biocatálise
Domínio Catalítico/genética
Sequência Conservada
Cristalografia por Raios X
Estrutura Molecular
Polissacarídeos
Pseudoalteromonas/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Polysaccharides); 0 (ulvan); EC 4.2.2.- (Polysaccharide-Lyases); EC 4.2.2.- (ulvan-lyase)
[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:170315
[St] Status:MEDLINE
[do] DOI:10.1021/acschembio.7b00126


  9 / 1926 MEDLINE  
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[PMID]:28276126
[Au] Autor:Hehemann JH; Truong LV; Unfried F; Welsch N; Kabisch J; Heiden SE; Junker S; Becher D; Thürmer A; Daniel R; Amann R; Schweder T
[Ad] Endereço:MARUM, Center for Marine Environmental Sciences at the University of Bremen, Leobener Strasse, Bremen, D-28359, Germany.
[Ti] Título:Aquatic adaptation of a laterally acquired pectin degradation pathway in marine gammaproteobacteria.
[So] Source:Environ Microbiol;19(6):2320-2333, 2017 Jun.
[Is] ISSN:1462-2920
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Mobile genomic islands distribute functional traits between microbes and habitats, yet it remains unclear how their proteins adapt to new environments. Here we used a comparative phylogenomic and proteomic approach to show that the marine bacterium Pseudoalteromonas haloplanktis ANT/505 acquired a genomic island with a functional pathway for pectin catabolism. Bioinformatics and biochemical experiments revealed that this pathway encodes a series of carbohydrate-active enzymes including two multi-modular pectate lyases, PelA and PelB. PelA is a large enzyme with a polysaccharide lyase family 1 (PL1) domain and a carbohydrate esterase family 8 domain, and PelB contains a PL1 domain and two carbohydrate-binding domains of family 13. Comparative phylogenomic analyses indicate that the pathway was most likely acquired from terrestrial microbes, yet we observed multi-modular orthologues only in marine bacteria. Proteomic experiments showed that P. haloplanktis ANT/505 secretes both pectate lyases into the environment in the presence of pectin. These multi-modular enzymes may therefore represent a marine innovation that enhances physical interaction with pectins to reduce loss of substrate and enzymes by diffusion. Our results revealed that marine bacteria can catabolize pectin, and highlight enzyme fusion as a potential adaptation that may facilitate microbial consumption of polymeric substrates in aquatic environments.
[Mh] Termos MeSH primário: Adaptação Fisiológica/genética
Gammaproteobacteria/metabolismo
Pectinas/metabolismo
Polissacarídeo-Liase/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Gammaproteobacteria/genética
Transferência Genética Horizontal/genética
Sequências Repetitivas Dispersas/genética
Proteômica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Pectins); EC 4.2.2.- (Polysaccharide-Lyases); EC 4.2.2.2 (pectate lyase)
[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:170310
[St] Status:MEDLINE
[do] DOI:10.1111/1462-2920.13726


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[PMID]:28205313
[Au] Autor:Zhu Y; Thomas F; Larocque R; Li N; Duffieux D; Cladière L; Souchaud F; Michel G; McBride MJ
[Ad] Endereço:Department of Biological Sciences, University of Wisconsin-Milwaukee, P. O. Box 413, Milwaukee, WI, 53201, USA.
[Ti] Título:Genetic analyses unravel the crucial role of a horizontally acquired alginate lyase for brown algal biomass degradation by Zobellia galactanivorans.
[So] Source:Environ Microbiol;19(6):2164-2181, 2017 Jun.
[Is] ISSN:1462-2920
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Comprehension of the degradation of macroalgal polysaccharides suffers from the lack of genetic tools for model marine bacteria, despite their importance for coastal ecosystem functions. We developed such tools for Zobellia galactanivorans, an algae-associated flavobacterium that digests many polysaccharides, including alginate. These tools were used to investigate the biological role of AlyA1, the only Z. galactanivorans alginate lyase known to be secreted in soluble form and to have a recognizable carbohydrate-binding domain. A deletion mutant, ΔalyA1, grew as well as the wild type on soluble alginate but was deficient in soluble secreted alginate lyase activity and in digestion of and growth on alginate gels and algal tissues. Thus, AlyA1 appears to be essential for optimal attack of alginate in intact cell walls. alyA1 appears to have been recently acquired via horizontal transfer from marine Actinobacteria, conferring an adaptive advantage that might benefit other algae-associated bacteria by exposing new substrate niches. The genetic tools described here function in diverse members of the phylum Bacteroidetes and should facilitate analyses of polysaccharide degradation systems and many other processes in these common but understudied bacteria.
[Mh] Termos MeSH primário: Alginatos/metabolismo
Flavobacteriaceae/genética
Flavobacteriaceae/metabolismo
Feófitas/microbiologia
Polissacarídeo-Liase/genética
[Mh] Termos MeSH secundário: Biomassa
Parede Celular/metabolismo
Flavobacteriaceae/enzimologia
Flavobacteriaceae/crescimento & desenvolvimento
Ácido Glucurônico/metabolismo
Ácidos Hexurônicos/metabolismo
Polissacarídeo-Liase/metabolismo
Deleção de Sequência/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alginates); 0 (Hexuronic Acids); 8A5D83Q4RW (Glucuronic Acid); 8C3Z4148WZ (alginic acid); EC 4.2.2.- (Polysaccharide-Lyases); EC 4.2.2.3 (poly(beta-D-mannuronate) lyase)
[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:170217
[St] Status:MEDLINE
[do] DOI:10.1111/1462-2920.13699



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