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  1 / 1610 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


  2 / 1610 MEDLINE  
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[PMID]:28290057
[Au] Autor:March DS; Marchbank T; Playford RJ; Jones AW; Thatcher R; Davison G
[Ad] Endereço:Department of Infection, Immunity and Inflammation, College of Medicine, Biological Sciences and Psychology, University of Leicester, Leicester, UK.
[Ti] Título:Intestinal fatty acid-binding protein and gut permeability responses to exercise.
[So] Source:Eur J Appl Physiol;117(5):931-941, 2017 May.
[Is] ISSN:1439-6327
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Intestinal cell damage due to physiological stressors (e.g. heat, oxidative, hypoperfusion/ischaemic) may contribute to increased intestinal permeability. The aim of this study was to assess changes in plasma intestinal fatty acid-binding protein (I-FABP) in response to exercise (with bovine colostrum supplementation, Col, positive control) and compare this to intestinal barrier integrity/permeability (5 h urinary lactulose/rhamnose ratio, L/R). METHODS: In a double-blind, placebo-controlled, crossover design, 18 males completed two experimental arms (14 days of 20 g/day supplementation with Col or placebo, Plac). For each arm participants performed two baseline (resting) intestinal permeability assessments (L/R) pre-supplementation and one post-exercise following supplementation. Blood samples were collected pre- and post-exercise to determine I-FABP concentration. RESULTS: Two-way repeated measures ANOVA revealed an arm × time interaction for L/R and I-FABP (P < 0.001). Post hoc analyses showed urinary L/R increased post-exercise in Plac (273% of pre, P < 0.001) and Col (148% of pre, P < 0.001) with post-exercise values significantly lower with Col (P < 0.001). Plasma I-FABP increased post-exercise in Plac (191% of pre-exercise, P = 0.002) but not in the Col arm (107%, P = 0.862) with post-exercise values significantly lower with Col (P = 0.013). Correlations between the increase in I-FABP and L/R were evident for visit one (P = 0.044) but not visit two (P = 0.200) although overall plots/patterns do appear similar for each. CONCLUSION: These findings suggest that exercise-induced intestinal cellular damage/injury is partly implicated in changes in permeability but other factors must also contribute.
[Mh] Termos MeSH primário: Exercício
Proteínas de Ligação a Ácido Graxo/sangue
Absorção Intestinal
Mucosa Intestinal/metabolismo
[Mh] Termos MeSH secundário: Adulto
Animais
Bovinos
Colostro
Seres Humanos
Lactulose/urina
Masculino
Ramnose/urina
[Pt] Tipo de publicação:JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL
[Nm] Nome de substância:
0 (Fatty Acid-Binding Proteins); 4618-18-2 (Lactulose); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170629
[Lr] Data última revisão:
170629
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170315
[St] Status:MEDLINE
[do] DOI:10.1007/s00421-017-3582-4


  3 / 1610 MEDLINE  
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[PMID]:28287471
[Au] Autor:Yu BW; Sun JJ; Pan JT; Wu XH; Yin YQ; Yan YS; Hu JY
[Ad] Endereço:School of Traditional Chinese Medicinal Chemistry, Guangdong Pharmaceutical University, Guangzhou 510006, China. bondbeth@126.com.
[Ti] Título:Four Pentasaccharide Resin Glycosides from Argyreia acuta.
[So] Source:Molecules;22(3), 2017 Mar 11.
[Is] ISSN:1420-3049
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Four pentasaccharide resin glycosides, acutacoside F-I ( - ), were isolated from the aerial parts of . These compounds were characterized as a group of macrolactones of operculinic acid A, and their lactonization site of 11 -hydroxyhexadecanoic acid was esterified at the second saccharide moiety (Rhamnose) at C-2. The absolute configuration of the aglycone was . Their structures were elucidated by established spectroscopic and chemical methods.
[Mh] Termos MeSH primário: Glicosídeos/química
Ipomoea/química
Lactonas/química
Oligossacarídeos/química
Resinas Vegetais/química
[Mh] Termos MeSH secundário: Glicosídeos/isolamento & purificação
Lactonas/isolamento & purificação
Estrutura Molecular
Oligossacarídeos/isolamento & purificação
Ácidos Palmíticos/química
Componentes Aéreos da Planta/química
Extratos Vegetais/química
Ramnose/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Glycosides); 0 (Lactones); 0 (Oligosaccharides); 0 (Palmitic Acids); 0 (Plant Extracts); 0 (Resins, Plant); 0 (operculinic acid); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170515
[Lr] Data última revisão:
170515
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170314
[St] Status:MEDLINE


  4 / 1610 MEDLINE  
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[PMID]:28190803
[Au] Autor:Kojima H; Shinohara R; Itonori S; Ito M
[Ad] Endereço:Department of Bioinformatics, College of Life Sciences, Ritsumeikan University.
[Ti] Título:Characterization of a Novel Rhamnose-containing Acidic Glycosphingolipid from the Ascidian Halocynthia aurantium.
[So] Source:J Oleo Sci;66(3):285-295, 2017 Mar 01.
[Is] ISSN:1347-3352
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Halocynthia aurantium, an edible ascidian species belonging to Urochordata, was subjected to structural characterization of acidic glycosphingolipids to investigate these molecules in ascidians: sulfatide from Ciona intestinalis and the glucuronic acid-containing acidic glycosphingolipid from H. roretzi. Acidic glycosphingolipids containing three or five sugars were isolated from soft parts of the ascidian H. aurantium by chloroform-methanol extraction, mild-alkaline hydrolysis, precipitation with cold acetone, and subsequent column chromatography using a DEAE-Sephadex A-25 column, a Florisil column, and an Iatrobead column. The structures of these glycosphingolipids were determined by methylation studies, sugar analysis, fatty acid analysis, sphingoid analysis, mass spectrometry, and proton nuclear magnetic resonance spectroscopy. A novel glucuronic acid-containing glycosphingolipid having a rhamnose residue was identified as Rhaα1-3GlcNAcß1-3Galß1-4(Fucα1-3)GlcAß1-Cer (UGL-2). This novel structure is particularly unusual given that it contains both a rhamnose residue and a reducing terminal glucuronic acid residue within a single molecule. Rhamnose is a characteristic sugar, which is a component of cell wall pectin in plants and exopolysaccharides in bacteria. Ascidians acquired the cellulose synthase gene via lateral gene transfer, and therefore, it can be speculated that they also acquired the rhamnosyltransferase gene in the same manner. We also detected Galß1-4(Fucα1-3)GlcAß1-Cer (UGL-1), which was already identified in another ascidian, H. roretzi.
[Mh] Termos MeSH primário: Glicoesfingolipídeos Acídicos/química
Ramnose/química
Urocordados/química
[Mh] Termos MeSH secundário: Glicoesfingolipídeos Acídicos/isolamento & purificação
Animais
Sequência de Carboidratos
Ceramidas/química
Cromatografia por Troca Iônica
Espectrometria de Massas
Estereoisomerismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acidic Glycosphingolipids); 0 (Ceramides); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170615
[Lr] Data última revisão:
170615
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170214
[St] Status:MEDLINE
[do] DOI:10.5650/jos.ess16150


  5 / 1610 MEDLINE  
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[PMID]:28173753
[Au] Autor:Hong TP; Carter MQ; Struffi P; Casonato S; Hao Y; Lam JS; Lory S; Jousson O
[Ad] Endereço:Centre for Integrative Biology, University of Trento, 38123, Trento, Italy.
[Ti] Título:Conjugative type IVb pilus recognizes lipopolysaccharide of recipient cells to initiate PAPI-1 pathogenicity island transfer in Pseudomonas aeruginosa.
[So] Source:BMC Microbiol;17(1):31, 2017 Feb 07.
[Is] ISSN:1471-2180
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Pseudomonas aeruginosa pathogenicity island 1 (PAPI-1) is one of the largest genomic islands of this important opportunistic human pathogen. Previous studies have shown that PAPI-1 encodes several putative virulence factors, including a major regulator of biofilm formation and antibiotic-resistance traits. PAPI-1 is horizontally transferable into recipient strains lacking this island via conjugation mediated by the specialized type IV pilus. The PAPI-1 encodes a cluster of ten genes associated with the synthesis and assembly of the type IV pilus. The PAPI-1 acquisition mechanism is currently not well understood. RESULTS: In this study, we performed a series of conjugation experiments and identified determinants of PAPI-1 acquisition by analyzing transfer efficiency between the donor and a series of mutant recipient strains. Our data show that common polysaccharide antigen (CPA) lipopolysaccharide (LPS), a homopolymer of D-rhamnose, is required for initiating PAPI-1 transfer, suggesting that this structure acts as a receptor for conjugative type IV pilus in recipient strains. These results were substantiated by experimental evidence from PAPI-1 transfer assay experiments, in which outer membrane or LPS preparations from well-defined LPS mutants were added to the transfer mix to assess the role of P. aeruginosa LPS in PAPI-1 transfer and in vitro binding experiments between pilin fusion protein GST-pilV2' and immobilized LPS molecules were performed. Our data also showed that P. aeruginosa strains that had already acquired a copy of PAPI-1 were unable to import additional copies of the island, and that such strains produced proportionally lower amounts of CPA LPS compared to the strains lacking PAPI-1. CONCLUSIONS: These results suggest that a PAPI-1 exclusion mechanism exists in P. aeruginosa that might serve to regulate the avoidance of uncontrolled expansions of the bacterial genome.
[Mh] Termos MeSH primário: Transferência Genética Horizontal
Ilhas Genômicas/genética
Lipopolissacarídeos/metabolismo
Pseudomonas aeruginosa/genética
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Membrana Celular/química
Cromossomos Bacterianos
Conjugação Genética/genética
Conjugação Genética/fisiologia
Fímbrias Bacterianas/genética
Regulação Bacteriana da Expressão Gênica
Genoma Bacteriano/genética
Genoma Bacteriano/fisiologia
Ilhas Genômicas/efeitos dos fármacos
Seres Humanos
Lipopolissacarídeos/química
Família Multigênica
Mutação
Infecções por Pseudomonas/microbiologia
Pseudomonas aeruginosa/patogenicidade
Ramnose/farmacologia
Fatores de Virulência/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Lipopolysaccharides); 0 (Virulence Factors); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170831
[Lr] Data última revisão:
170831
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170209
[St] Status:MEDLINE
[do] DOI:10.1186/s12866-017-0943-4


  6 / 1610 MEDLINE  
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[PMID]:28159311
[Au] Autor:Saleem B; Okogbule-Wonodi AC; Fasano A; Magder LS; Ravel J; Kapoor S; Viscardi RM
[Ad] Endereço:Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD.
[Ti] Título:Intestinal Barrier Maturation in Very Low Birthweight Infants: Relationship to Feeding and Antibiotic Exposure.
[So] Source:J Pediatr;183:31-36.e1, 2017 Apr.
[Is] ISSN:1097-6833
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: To test the hypothesis that feeding and antibiotic exposures affect intestinal barrier maturation in preterm infants, we serially measured intestinal permeability (IP) biomarkers in infants <33 weeks gestation (gestational age [GA]) during the first 2 weeks of life. STUDY DESIGN: Eligible infants <33 weeks GA were enrolled within 4 days of birth in a prospective study of IP biomarkers (NCT01756040). Study participants received the nonmetabolized sugars lactulose/rhamnose enterally on study days 1, 8, and 15 and lactulose/rhamnose were measured in urine by high-performance liquid chromatography. Serum zonulin and fecal alpha-1-anti-trypsin, 2 other IP markers, were measured by semiquantitative Western blot and ELISA, respectively. RESULTS: In a cohort of 43 subjects, the lactulose/rhamnose ratio was increased on day 1 and decreased over 2 weeks, but remained higher in infants born at ≤28 weeks of gestation compared with IP in infants born at >28 weeks of gestation. Exclusive breastmilk feeding was associated with more rapid maturation in intestinal barrier function. A cluster analysis of 35 subjects who had urine samples from all time points revealed 3 IP patterns (cluster 1, normal maturation: n = 20 [57%]); cluster 2, decreased IP during the first week and subsequent substantial increase: n = 5 [14%]); and cluster 3, delayed maturation: n = 10 [29%]). There were trends toward more prolonged antibiotic exposure (P = .092) and delayed initiation of feeding ≥4 days (P = .064) in infants with abnormal IP patterns. CONCLUSIONS: Intestinal barrier maturation in preterm infants is GA and postnatal age dependent, and is influenced by feeding with a maturational effect of breastmilk feeding and possibly by antibiotic exposures. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01756040.
[Mh] Termos MeSH primário: Antibacterianos/administração & dosagem
Recém-Nascido de muito Baixo Peso/metabolismo
Absorção Intestinal/fisiologia
Leite Humano/metabolismo
[Mh] Termos MeSH secundário: Análise de Variância
Antibacterianos/farmacocinética
Biomarcadores/análise
Estudos de Casos e Controles
Desenvolvimento Infantil/fisiologia
Métodos de Alimentação
Feminino
Seguimentos
Idade Gestacional
Seres Humanos
Lactente
Fórmulas Infantis
Fenômenos Fisiológicos da Nutrição do Lactente
Recém-Nascido
Intestinos/efeitos dos fármacos
Intestinos/metabolismo
Lactose/administração & dosagem
Lactose/farmacocinética
Masculino
Permeabilidade/efeitos dos fármacos
Estudos Prospectivos
Ramnose/administração & dosagem
Ramnose/farmacocinética
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Biomarkers); J2B2A4N98G (Lactose); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170615
[Lr] Data última revisão:
170615
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170205
[St] Status:MEDLINE


  7 / 1610 MEDLINE  
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[PMID]:28120309
[Au] Autor:Thuan NH; Malla S; Trung NT; Dhakal D; Pokhrel AR; Chu LL; Sohng JK
[Ad] Endereço:Center for Molecular Biology, Institute of Research and Development, Duy Tan University, K7/25 Quang Trung, Danang, Vietnam. thuanbiochem@gmail.com.
[Ti] Título:Microbial production of astilbin, a bioactive rhamnosylated flavanonol, from taxifolin.
[So] Source:World J Microbiol Biotechnol;33(2):36, 2017 Feb.
[Is] ISSN:1573-0972
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Flavonoids are plant-based polyphenolic biomolecules with a wide range of biological activities. Glycosylated flavonoids have drawn special attention in the industries as it improves solubility, stability, and bioactivity. Herein, we report the production of astilbin (ATN) from taxifolin (TFN) in genetically-engineered Escherichia coli BL21(DE3). The exogenously supplied TFN was converted to ATN by 3-O-rhamnosylation utilizing the endogeneous TDP-L-rhamnose in presence of UDP-glycosyltransferase (ArGT3, Gene Bank accession number: At1g30530) from Arabidopsis thaliana. Upon improving the intracellular TDP-L-rhamnose pool by knocking out the chromosomal glucose phosphate isomerase (pgi) and D-glucose-6-phosphate dehydrogenase (zwf) deletion along with the overexpression of rhamnose biosynthetic pathway increases the biotransformation product, ATN with total conversion of ~49.5 ± 1.67% from 100 µM of taxifolin. In addition, the cytotoxic effect of taxifolin-3-O-rhamnoside on PANC-1 and A-549 cancer cell lines was assessed for establishing ATN as potent antitumor compound.
[Mh] Termos MeSH primário: Antineoplásicos/farmacologia
Flavonóis/biossíntese
Glicosiltransferases/metabolismo
Quercetina/análogos & derivados
Ramnose/metabolismo
[Mh] Termos MeSH secundário: Antineoplásicos/química
Proteínas de Arabidopsis/genética
Proteínas de Arabidopsis/metabolismo
Vias Biossintéticas
Linhagem Celular Tumoral
Sobrevivência Celular/efeitos dos fármacos
Escherichia coli/enzimologia
Escherichia coli/genética
Técnicas de Inativação de Genes
Engenharia Genética/métodos
Glicosilação
Glicosiltransferases/genética
Seres Humanos
Quercetina/metabolismo
Quercetina/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antineoplastic Agents); 0 (Arabidopsis Proteins); 0 (Flavonols); 29838-67-3 (astilbin); 9IKM0I5T1E (Quercetin); 9SOB9E3987 (taxifolin); EC 2.4.- (Glycosyltransferases); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170126
[St] Status:MEDLINE
[do] DOI:10.1007/s11274-017-2208-7


  8 / 1610 MEDLINE  
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[PMID]:27988798
[Au] Autor:Wittgens A; Kovacic F; Müller MM; Gerlitzki M; Santiago-Schübel B; Hofmann D; Tiso T; Blank LM; Henkel M; Hausmann R; Syldatk C; Wilhelm S; Rosenau F
[Ad] Endereço:Ulm Center for Peptide Pharmaceuticals (U-PEP), Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany. andreas.wittgens@uni-ulm.de.
[Ti] Título:Novel insights into biosynthesis and uptake of rhamnolipids and their precursors.
[So] Source:Appl Microbiol Biotechnol;101(7):2865-2878, 2017 Apr.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:The human pathogenic bacterium Pseudomonas aeruginosa produces rhamnolipids, glycolipids with functions for bacterial motility, biofilm formation, and uptake of hydrophobic substrates. Rhamnolipids represent a chemically heterogeneous group of secondary metabolites composed of one or two rhamnose molecules linked to one or mostly two 3-hydroxyfatty acids of various chain lengths. The biosynthetic pathway involves rhamnosyltransferase I encoded by the rhlAB operon, which synthesizes 3-(3-hydroxyalkanoyloxy)alkanoic acids (HAAs) followed by their coupling to one rhamnose moiety. The resulting mono-rhamnolipids are converted to di-rhamnolipids in a third reaction catalyzed by the rhamnosyltransferase II RhlC. However, the mechanism behind the biosynthesis of rhamnolipids containing only a single fatty acid is still unknown. To understand the role of proteins involved in rhamnolipid biosynthesis the heterologous expression of rhl-genes in non-pathogenic Pseudomonas putida KT2440 strains was used in this study to circumvent the complex quorum sensing regulation in P. aeruginosa. Our results reveal that RhlA and RhlB are independently involved in rhamnolipid biosynthesis and not in the form of a RhlAB heterodimer complex as it has been previously postulated. Furthermore, we demonstrate that mono-rhamnolipids provided extracellularly as well as HAAs as their precursors are generally taken up into the cell and are subsequently converted to di-rhamnolipids by P. putida and the native host P. aeruginosa. Finally, our results throw light on the biosynthesis of rhamnolipids containing one fatty acid, which occurs by hydrolyzation of typical rhamnolipids containing two fatty acids, valuable for the production of designer rhamnolipids with desired physicochemical properties.
[Mh] Termos MeSH primário: Vias Biossintéticas/genética
Ácidos Graxos/metabolismo
Glicolipídeos/biossíntese
Glicolipídeos/metabolismo
Pseudomonas putida/genética
Pseudomonas putida/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Cromatografia Líquida de Alta Pressão
Decanoatos/metabolismo
Glicolipídeos/química
Glicolipídeos/isolamento & purificação
Mutação
Óperon
Pseudomonas aeruginosa/genética
Percepção de Quorum
Ramnose/análogos & derivados
Ramnose/metabolismo
Tensoativos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Decanoates); 0 (Fatty Acids); 0 (Glycolipids); 0 (Surface-Active Agents); 0 (rhamnolipid); 37134-61-5 (rhamnopyranosyl-3-hydroxydecanoyl-3-hydroxydecanoate); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170405
[Lr] Data última revisão:
170405
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161219
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-016-8041-3


  9 / 1610 MEDLINE  
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[PMID]:27881199
[Au] Autor:Gilani S; Howarth GS; Kitessa SM; Tran CD; Forder REA; Hughes RJ
[Ad] Endereço:1School of Animal and Veterinary Sciences,University of Adelaide,Roseworthy Campus,Adelaide, SA 5371,Australia.
[Ti] Título:Intestinal permeability induced by lipopolysaccharide and measured by lactulose, rhamnose and mannitol sugars in chickens.
[So] Source:Animal;11(7):1174-1179, 2017 Jul.
[Is] ISSN:1751-732X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Increased intestinal permeability (IP) can lead to compromised health. Limited in vivo IP research has been conducted in chickens. The objectives of the current study were to develop a model of increased IP utilizing lipopolysaccharide (LPS Escherichia coli O55:B5) and to evaluate IP changes using the lactulose, mannitol and rhamnose (LMR) sugar permeability test. In addition, fluorescein isothiocyanate dextran (FITC-d), d-lactate, zonula occludens (ZO-1) and diamine oxidase (DAO) permeability tests were employed. Male Ross chickens were reared until day 14 on the floor in an animal care facility and then transferred to individual cages in three separate experiments. In each of experiments 1 and 2, 36 chicks were randomly allocated to receive either saline (control) or LPS (n=18/group). Lactulose, mannitol and rhamnose sugar concentration in blood was measured at 0, 30, 60, 90, 120 and 180 min in experiment 1, at 60, 90 and 120 min in experiment 2 and at 90 min in experiment 3 (n=16/group). Lipopolysaccharide was injected intraperitoneally at doses of 0.5, 1 and 1 mg/kg BW in experiments 1, 2 and 3, respectively, on days 16, 18 and 20, whereas control received sterile saline. On day 21, only birds in experiments 1 and 2 were fasted for 19.5 h. Chicks were orally gavaged with the LMR sugars (0.25 gL, 0.05 gM, 0.05 gR/bird) followed by blood collection (from the brachial vein) as per time point for each experiment. Only in experiment 3, were birds given an additional oral gavage of FITC-d (2.2 mg/ml per bird) 60 min after the first gavage. Plasma d-lactate, ZO-1 and DAO concentrations were also determined by ELISA in experiment 3 (n=10). Administration of LPS did not affect IP as measured by the LMR sugar test compared with control. This was also confirmed by FITC-d and DAO levels in experiment 3 (P>0.05). The plasma levels of d-lactate were decreased (P<0.05). Plasma levels of ZO-1 were increased in the third experiment only and did not change in the first two experiments. Lipopolysaccharide at doses of 0.5 and 1 mg/kg did not increase IP in this model system. In conclusion, the LMR sugar can be detected in blood 90 min after the oral gavage. Further studies are needed for the applicability of LMR sugars tests.
[Mh] Termos MeSH primário: Galinhas/fisiologia
Escherichia coli/química
Lipopolissacarídeos/administração & dosagem
Modelos Biológicos
[Mh] Termos MeSH secundário: Amina Oxidase (contendo Cobre)/sangue
Amina Oxidase (contendo Cobre)/metabolismo
Animais
Dextranos/análise
Dextranos/metabolismo
Fluoresceína-5-Isotiocianato/análogos & derivados
Fluoresceína-5-Isotiocianato/análise
Fluoresceína-5-Isotiocianato/metabolismo
Intestinos/fisiologia
Ácido Láctico/sangue
Ácido Láctico/metabolismo
Lactulose/sangue
Lactulose/metabolismo
Masculino
Manitol/sangue
Manitol/metabolismo
Permeabilidade/efeitos dos fármacos
Distribuição Aleatória
Ramnose/sangue
Ramnose/metabolismo
Junções Íntimas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Dextrans); 0 (Lipopolysaccharides); 0 (fluorescein isothiocyanate dextran); 33X04XA5AT (Lactic Acid); 3OWL53L36A (Mannitol); 4618-18-2 (Lactulose); EC 1.4.3.21 (Amine Oxidase (Copper-Containing)); I223NX31W9 (Fluorescein-5-isothiocyanate); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171012
[Lr] Data última revisão:
171012
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161125
[St] Status:MEDLINE
[do] DOI:10.1017/S1751731116002470


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[PMID]:27816868
[Au] Autor:Liley JR; Penfold J; Thomas RK; Tucker IM; Petkov JT; Stevenson PS; Banat IM; Marchant R; Rudden M; Terry A; Grillo I
[Ad] Endereço:Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford, UK.
[Ti] Título:Self-assembly in dilute mixtures of non-ionic and anionic surfactants and rhamnolipd biosurfactants.
[So] Source:J Colloid Interface Sci;487:493-503, 2017 Feb 01.
[Is] ISSN:1095-7103
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The self-assembly of dilute aqueous solutions of a ternary surfactant mixture and rhamnolipid biosurfactant/surfactant mixtures has been studied by small angle neutron scattering. In the ternary surfactant mixture of octaethylene glycol monododecyl ether, C E , sodium dodecyl 6-benzene sulfonate, LAS, and sodium dioxyethylene monododecyl sulfate, SLES, small globular interacting micelles are observed over the entire composition and concentration range studied. The modelling of the scattering data strongly supports the assumption that the micelle compositions are close to the solution compositions. In the 5-component rhamnolipid/surfactant mixture of the mono-rhamnose, R1, di-rhamnose, R2, rhamnolipids with C E /LAS/SLES, globular micelles are observed over much of the concentration and composition range studied. However, for solutions relatively rich in rhamnolipid and LAS, lamellar/micellar coexistence is observed. The transition from globular to more planar structures arises from a synergistic packing in the 5 component mixture. It is not observed in the individual components nor in the ternary C E /LAS/SLES mixture at these relatively low concentrations. The results provide an insight into how synergistic packing effects can occur in the solution self-assembly of complex multi-component surfactant mixtures, and give rise to an unexpected evolution in the phase behaviour.
[Mh] Termos MeSH primário: Alcanossulfonatos/química
Glicolipídeos/química
Tensoativos/química
Água/química
[Mh] Termos MeSH secundário: Benzenossulfonatos/química
Micelas
Difração de Nêutrons
Polietilenoglicóis/química
Ramnose/química
Espalhamento a Baixo Ângulo
Dodecilsulfato de Sódio/análogos & derivados
Dodecilsulfato de Sódio/química
Soluções
Tensão Superficial
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkanesulfonates); 0 (Benzenesulfonates); 0 (Glycolipids); 0 (Micelles); 0 (Solutions); 0 (Surface-Active Agents); 0 (rhamnolipid); 059QF0KO0R (Water); 3055-98-9 (dodecyloctaethyleneglycol monoether); 30IQX730WE (Polyethylene Glycols); 368GB5141J (Sodium Dodecyl Sulfate); 60NSK897G9 (dodecylbenzenesulfonic acid); BPV390UAP0 (sodium laureth sulfate); QN34XC755A (Rhamnose)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170917
[Lr] Data última revisão:
170917
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161107
[St] Status:MEDLINE



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