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Pesquisa : D09.947.875.359 [Categoria DeCS]
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  1 / 5100 MEDLINE  
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[PMID]:29313328
[Au] Autor:Lv J; Qian GF; Chen L; Liu H; Xu HX; Xu GR; Zhang BB; Zhang C
[Ad] Endereço:Key Laboratory of Carbohydrate Chemistry and Biotechnology, School of Biotechnology and ‡School of Food science and Technology, Jiangnan University , Wuxi 214122, China.
[Ti] Título:Efficient Biosynthesis of Natural Yellow Pigments by Monascus purpureus in a Novel Integrated Fermentation System.
[So] Source:J Agric Food Chem;66(4):918-925, 2018 Jan 31.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Because of the increasing demand for healthy and safe food, Monascus spp. have gained much attention as a sustainable source of natural food colorant. In this study, a novel integrated fermentation system consisting of surfactant and in situ extractant was established for efficiently producing yellow pigments by M. purpureus sjs-6. The maximum production of Monascus yellow pigment (669.2 U/mL) was obtained when 40% soybean oil (as extractant) was supplied at the beginning and 5 g/L Span-80 (as surfactant) was supplied at the 72nd h, which resulted in production 27.8-times of that of the control. Critical factors such as alleviating the product inhibition, increasing the membrane permeability, changing the hyphal morphology, and influencing the cell activity have been suggested as the underlying mechanisms. This system is of great significance for the bioprocess, which suffers product inhibition, and it can serve as a promising step for enhancing the yield of hydrophobic metabolites.
[Mh] Termos MeSH primário: Fermentação
Monascus/metabolismo
Pigmentos Biológicos/biossíntese
[Mh] Termos MeSH secundário: Permeabilidade da Membrana Celular
Ácidos Graxos/metabolismo
Hexoses
Microscopia Acústica
Monascus/fisiologia
Monascus/ultraestrutura
Óleo de Soja
Tensoativos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fatty Acids); 0 (Hexoses); 0 (Pigments, Biological); 0 (Surface-Active Agents); 06XEA2VD56 (sorbitan monooleate); 8001-22-7 (Soybean Oil)
[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:180110
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b05783


  2 / 5100 MEDLINE  
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[PMID]:28460348
[Au] Autor:Sizova OV; Kondakova AN; Shashkov AS; Knirel YA; Shaikhutdinova RZ; Ivanov SA; Platonov ME; Hurst MRH; Dentovskaya SV
[Ad] Endereço:N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991, Moscow, Russian Federation.
[Ti] Título:Structure and gene cluster of a tyvelose-containing O-polysaccharide of an entomopathogenic bacterium Yersinia entomophaga MH96 related to Yersinia pseudotuberculosis.
[So] Source:Carbohydr Res;445:93-97, 2017 Jun 05.
[Is] ISSN:1873-426X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:An O-polysaccharide was isolated from the lipopolysaccharide of an entomopathogenic bacterium Yersinia entomophaga MH96 by mild acid hydrolysis and studied by 2D NMR spectroscopy. The following structure of the branched tetrasaccharide repeating unit of the polysaccharide was established: where Tyv indicates 3,6-dideoxy-d-arabino-hexose (tyvelose). The structure established is consistent with the gene content of the O-antigen gene cluster. The O-polysaccharide structure and gene cluster of Y. entomophaga are related to those of some Y. pseudotuberculosis serotypes.
[Mh] Termos MeSH primário: Hexoses/química
Família Multigênica
Antígenos O/química
Yersinia pseudotuberculosis/química
Yersinia pseudotuberculosis/genética
[Mh] Termos MeSH secundário: Sequência de Carboidratos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hexoses); 0 (O Antigens); 5658-12-8 (tyvelose)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180125
[Lr] Data última revisão:
180125
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE


  3 / 5100 MEDLINE  
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[PMID]:29235834
[Au] Autor:Holota YV; Olefir YA; Dovbynchuk TV; Tolstanova GM
[Ti] Título:Carbohydrate composition of rat intestine surface mucus layer after ceftriaxone treatment.
[So] Source:Ukr Biochem J;88(6):35-44, 2016 Nov-Dec.
[Is] ISSN:2409-4943
[Cp] País de publicação:Ukraine
[La] Idioma:eng
[Ab] Resumo:The epidemiological studies have shown that antibiotic treatment increases the susceptibility to inflammatory bowel disease development. The disturbance of mucus layer integrity might be one of the possible mechanisms. The aim of the present study was to investigate the effect of antibiotic ceftriaxone treatment on glycoproteins level and its carbohydrate composition in surface mucus layer of rat intestine. The study was done on male Wistar rats (140-160 g). Ceftriaxone (300 mg/kg, i.m.) was administered once a day for 14 days. The surface mucus from terminal ileum and colon were collected on the 15th, 29th and 72nd days of the experiment. Total level of mucus glycoproteins, hexoses, hexosamines, fucose and sialic acids were measured. Ceftriaxone administration did not affect the levels of glycoproteins in rat ileum. In the colon, the levels of glycoprotein were 1.3-fold decreased (Р < 0.05) on the 72nd day of the experiment. These changes were accompanied by the 1.2-fold decrease of hexoses (Р < 0.05) and 3.1-fold (Р < 0.05) decrease of fucose level and 1.5-fold (Р < 0.05) increase of the levels of sialic acids in the surface mucus of the rat colon. Thus, ceftriaxone administration induces the long-term changes in the levels of glycoproteins and carbohydrates composition in the rat colon surface mucus. This could potentially explain the susceptibility to inflammatory bowel disea­ses development.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Ceftriaxona/farmacologia
Colo/efeitos dos fármacos
Íleo/efeitos dos fármacos
Muco/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Colo/química
Colo/metabolismo
Esquema de Medicação
Fucose/metabolismo
Glicoproteínas/metabolismo
Hexosaminas/metabolismo
Hexoses/metabolismo
Íleo/química
Íleo/metabolismo
Injeções Intramusculares
Masculino
Muco/química
Muco/metabolismo
Ratos
Ratos Wistar
Ácidos Siálicos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Glycoproteins); 0 (Hexosamines); 0 (Hexoses); 0 (Sialic Acids); 28RYY2IV3F (Fucose); 75J73V1629 (Ceftriaxone)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180116
[Lr] Data última revisão:
180116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171214
[St] Status:MEDLINE
[do] DOI:10.15407/ubj88.06.035


  4 / 5100 MEDLINE  
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[PMID]:28708852
[Au] Autor:Ferreira SJ; Senning M; Fischer-Stettler M; Streb S; Ast M; Neuhaus HE; Zeeman SC; Sonnewald S; Sonnewald U
[Ad] Endereço:Department of Biology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany.
[Ti] Título:Simultaneous silencing of isoamylases ISA1, ISA2 and ISA3 by multi-target RNAi in potato tubers leads to decreased starch content and an early sprouting phenotype.
[So] Source:PLoS One;12(7):e0181444, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Isoamylases hydrolyse (1-6)-alpha-D-glucosidic linkages in starch and are involved in both starch granule formation and starch degradation. In plants, three isoamylase isoforms with distinct functions in starch synthesis (ISA1 and ISA2) and degradation (ISA3) have been described. Here, we created transgenic potato plants with simultaneously decreased expression of all three isoamylases using a chimeric RNAi construct targeting all three isoforms. Constitutive expression of the hairpin RNA using the 35S CaMV promoter resulted in efficient silencing of all three isoforms in leaves, growing tubers, and sprouting tubers. Neither plant growth nor tuber yield was effected in isoamylase-deficient potato lines. Interestingly, starch metabolism was found to be impaired in a tissue-specific manner. While leaf starch content was unaffected, tuber starch was significantly reduced. The reduction in tuber starch content in the transgenic plants was accompanied by a decrease in starch granules size, an increased sucrose content and decreased hexose levels. Despite the effects on granule size, only little changes in chain length composition of soluble and insoluble glucose polymers were detected. The transgenic tubers displayed an early sprouting phenotype that was accompanied by an increased level of sucrose in parenchyma cells below the outgrowing bud. Since high sucrose levels promote sprouting, we propose that the increased number of small starch granules may cause an accelerated turnover of glucan chains and hence a more rapid synthesis of sucrose. This observation links alterations in starch structure/degradation with developmental processes like meristem activation and sprout outgrowth in potato tubers.
[Mh] Termos MeSH primário: Isoamilase/metabolismo
Proteínas de Plantas/metabolismo
Interferência de RNA
Amido/metabolismo
[Mh] Termos MeSH secundário: Hexoses/metabolismo
Isoamilase/antagonistas & inibidores
Isoamilase/genética
Fenótipo
Folhas de Planta/metabolismo
Proteínas de Plantas/antagonistas & inibidores
Proteínas de Plantas/genética
Tubérculos/metabolismo
Plantas Geneticamente Modificadas/metabolismo
Isoformas de Proteínas/antagonistas & inibidores
Isoformas de Proteínas/genética
Isoformas de Proteínas/metabolismo
RNA Interferente Pequeno/metabolismo
Plântulas/fisiologia
Solanum tuberosum/crescimento & desenvolvimento
Solanum tuberosum/metabolismo
Sacarose/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hexoses); 0 (Plant Proteins); 0 (Protein Isoforms); 0 (RNA, Small Interfering); 57-50-1 (Sucrose); 9005-25-8 (Starch); EC 3.2.1.68 (Isoamylase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170715
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0181444


  5 / 5100 MEDLINE  
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[PMID]:28600864
[Au] Autor:Chappell TC; Nair NU
[Ad] Endereço:Department of Chemical and Biological Engineering, Tufts University, Medford, Massachusetts 02155.
[Ti] Título:Co-utilization of hexoses by a microconsortium of sugar-specific E. coli strains.
[So] Source:Biotechnol Bioeng;114(10):2309-2318, 2017 Oct.
[Is] ISSN:1097-0290
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Escherichia coli is an important commercial species used for production of biofuels, biopolymers, organic acids, sugar alcohols, and natural compounds. Processed biomass and agroindustrial byproducts serve as low-cost nutrient sources and contain a variety of hexoses available for bioconversion. However, metabolism of hexose mixtures by E. coli is inefficient due to carbon catabolite repression (CCR), where the transport and catabolic activity of one or more carbon sources is repressed and/or inhibited by the transport and catabolism of another carbon source. In this work, we developed a microconsortium of different E. coli strains, each engineered to preferentially catabolize a different hexose-glucose, galactose, or mannose. We modified the specificity and preference of carbon source using a combination of rational strain design and adaptive evolution. The modifications ultimately resulted in strains that preferentially catabolized their specified sugar. Finally, comparative analysis in galactose- and mannose-rich sugar mixtures revealed that the consortium grew faster and to higher cell densities compared to the wild-type strain. Biotechnol. Bioeng. 2017;114: 2309-2318. © 2017 Wiley Periodicals, Inc.
[Mh] Termos MeSH primário: Técnicas de Cultura Celular por Lotes/métodos
Escherichia coli/classificação
Escherichia coli/fisiologia
Melhoramento Genético/métodos
Hexoses/metabolismo
Consórcios Microbianos/fisiologia
[Mh] Termos MeSH secundário: Comunicação Celular/fisiologia
Proliferação Celular/fisiologia
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hexoses)
[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:170611
[St] Status:MEDLINE
[do] DOI:10.1002/bit.26351


  6 / 5100 MEDLINE  
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[PMID]:28556908
[Au] Autor:Hykollari A; Malzl D; Yan S; Wilson IBH; Paschinger K
[Ad] Endereço:Department für Chemie, Universität für Bodenkultur, Wien, Austria.
[Ti] Título:Hydrophilic interaction anion exchange for separation of multiply modified neutral and anionic Dictyostelium N-glycans.
[So] Source:Electrophoresis;38(17):2175-2183, 2017 09.
[Is] ISSN:1522-2683
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:The unusual nature of the N-glycans of the cellular slime mould Dictyostelium discoideum has been revealed by a number of studies, primarily based on examination of radiolabeled glycopeptides but more recently also by MS. The complexity of the N-glycomes of even glycosylation mutants is compounded by the occurrence of anionic modifications, which also present an analytical challenge. In this study, we have employed hydrophilic interaction anion exchange (HIAX) HPLC in combination with MALDI-TOF MS/MS to explore the anionic N-glycome of the M31 (modA) strain, which lacks endoplasmic reticulum α-glucosidase II, an enzyme conserved in most eukaryotes including Homo sapiens. Prefractionation with HIAX chromatography enabled the identification of N-glycans with unusual oligo-α1,2-mannose extensions as well as others with up to four anionic modifications. Due to the use of hydrofluoric acid treatment, we were able to discriminate isobaric glycans differing in the presence of sulphate or phosphate on intersected structures as opposed to those carrying GlcNAc-phosphodiesters. The latter represent biosynthetic intermediates during the pathway leading to formation of the methylphosphorylated mannose epitope, which may have a similar function in intracellular targeting of hydrolases as the mannose-6-phosphate modification of lysosomal enzymes in mammals. In conclusion, HIAX in combination with MS is a highly sensitive approach for both fine separation and definition of neutral and anionic N-glycan structures.
[Mh] Termos MeSH primário: Cromatografia por Troca Iônica/métodos
Dictyostelium/química
Glicômica/métodos
Polissacarídeos/análise
Polissacarídeos/química
[Mh] Termos MeSH secundário: Cromatografia Líquida de Alta Pressão/métodos
Dictyostelium/metabolismo
Hexoses/análise
Hexoses/química
Interações Hidrofóbicas e Hidrofílicas
Manose/análise
Manose/química
Fosfatos/análise
Fosfatos/química
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
Sulfatos/análise
Sulfatos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Hexoses); 0 (Phosphates); 0 (Polysaccharides); 0 (Sulfates); PHA4727WTP (Mannose)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170531
[St] Status:MEDLINE
[do] DOI:10.1002/elps.201700073


  7 / 5100 MEDLINE  
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[PMID]:28530095
[Au] Autor:Zheng Z; Mei W; Xia M; He Q; Ouyang J
[Ad] Endereço:Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources , Nanjing 210037, People's Republic of China.
[Ti] Título:Rational Design of Bacillus coagulans NL01 l-Arabinose Isomerase and Use of Its F279I Variant in d-Tagatose Production.
[So] Source:J Agric Food Chem;65(23):4715-4721, 2017 Jun 14.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:d-Tagatose is a prospective functional sweetener that can be produced by l-arabinose isomerase (AI) from d-galactose. To improve the activity of AI toward d-galactose, the AI of Bacillus coagulans was rationally designed on the basis of molecular modeling and docking. After alanine scanning and site-saturation mutagenesis, variant F279I that exhibited improved activity toward d-galactose was obtained. The optimal temperature and pH of F279I were determined to be 50 °C and 8.0, respectively. This variant possessed 1.4-fold catalytic efficiency compared with the wild-type (WT) enzyme. The recombinant Escherichia coli overexpressing F279I also showed obvious advantages over the WT in biotransformation. Under optimal conditions, 67.5 and 88.4 g L d-tagatose could be produced from 150 and 250 g L d-galactose, respectively, in 15 h. The biocatalyst constructed in this study presents a promising alternative for large-scale d-tagatose production.
[Mh] Termos MeSH primário: Aldose-Cetose Isomerases/genética
Bacillus coagulans/enzimologia
Proteínas de Bactérias/genética
Hexoses/biossíntese
[Mh] Termos MeSH secundário: Aldose-Cetose Isomerases/química
Aldose-Cetose Isomerases/metabolismo
Bacillus coagulans/genética
Bacillus coagulans/metabolismo
Proteínas de Bactérias/química
Proteínas de Bactérias/metabolismo
Clonagem Molecular
Estabilidade Enzimática
Escherichia coli/genética
Escherichia coli/metabolismo
Galactose/metabolismo
Edulcorantes/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Hexoses); 0 (Sweetening Agents); EC 5.3.1.- (Aldose-Ketose Isomerases); EC 5.3.1.4 (L-arabinose isomerase); T7A20Y888Y (tagatose); X2RN3Q8DNE (Galactose)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170626
[Lr] Data última revisão:
170626
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170523
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b01709


  8 / 5100 MEDLINE  
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[PMID]:28420295
[Au] Autor:Zidan AS; Mokhtar Ibrahim M; Megrab NAE
[Ad] Endereço:a Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy , Zagazig University , Zagazig , Egypt.
[Ti] Título:Optimization of methotrexate loaded niosomes by Box-Behnken design: an understanding of solvent effect and formulation variability.
[So] Source:Drug Dev Ind Pharm;43(9):1450-1459, 2017 Sep.
[Is] ISSN:1520-5762
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Dermal drug delivery system which localizes methotrexate (MTX) in the skin is advantageous in topical treatment of psoriasis. The aim of the current study was to understand dilution effects and formulation variability for the potential formation of niosomes from proniosome gels of MTX. Box-Behnken's design was employed to prepare a series of MTX proniosome gels of Span 40, cholesterol (Chol-X ) and Tween 20 (T20-X ). Short chain alcohols (X ), namely ethanol (Et), propylene glycol (Pg) and glycerol (G) were evaluated for their dilution effects on proniosomes. The responses investigated were niosomal vesicles size (Y ), MTX entrapment efficiency percent (EE%-Y ) and zeta potential (Y ). MTX loaded niosomes were formed immediately upon hydration of the proniosome gels with the employed solvents. Addition of Pg resulted in a decrease of vesicular size from 534 nm to 420 nm as Chol percentage increased from 10% to 30%, respectively. In addition, increasing the hydrophilicity of the employed solvents was enhancing the resultant zeta potential. On the other hand, using Et in proniosomal gels would abolish Chol action to increase the zeta potential value and hence less stable niosomal dispersion was formed. The optimized formula of MTX loaded niosomes showed vesicle size of 480 nm, high EE% (55%) and zeta potential of -25.5 mV, at Chol and T20 concentrations of 30% and 23.6%, respectively, when G was employed as the solvent. Hence, G was the solvent of choice to prepare MTX proniosomal gels with a maintained stability and highest entrapment.
[Mh] Termos MeSH primário: Colesterol/química
Sistemas de Liberação de Medicamentos/métodos
Géis/química
Hexoses/administração & dosagem
Hexoses/farmacocinética
Lipossomos/química
Lipossomos/metabolismo
Metotrexato/administração & dosagem
Metotrexato/farmacocinética
Pele/metabolismo
Solventes/química
Tensoativos/química
[Mh] Termos MeSH secundário: Administração Cutânea
Administração Tópica
Química Farmacêutica
Colesterol/metabolismo
Hexoses/química
Metotrexato/química
Solubilidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Gels); 0 (Hexoses); 0 (Liposomes); 0 (Solvents); 0 (Surface-Active Agents); 77K6Z421KU (sorbitan monopalmitate); 97C5T2UQ7J (Cholesterol); YL5FZ2Y5U1 (Methotrexate)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170420
[St] Status:MEDLINE
[do] DOI:10.1080/03639045.2017.1318907


  9 / 5100 MEDLINE  
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[PMID]:28410570
[Au] Autor:Valadez-Cano C; Olivares-Hernández R; Resendis-Antonio O; DeLuna A; Delaye L
[Ad] Endereço:Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Irapuato, Km. 9.6 Libramiento Norte Carr. Irapuato-León, 36821, Guanajuato, Irapuato, Mexico.
[Ti] Título:Natural selection drove metabolic specialization of the chromatophore in Paulinella chromatophora.
[So] Source:BMC Evol Biol;17(1):99, 2017 Apr 14.
[Is] ISSN:1471-2148
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Genome degradation of host-restricted mutualistic endosymbionts has been attributed to inactivating mutations and genetic drift while genes coding for host-relevant functions are conserved by purifying selection. Unlike their free-living relatives, the metabolism of mutualistic endosymbionts and endosymbiont-originated organelles is specialized in the production of metabolites which are released to the host. This specialization suggests that natural selection crafted these metabolic adaptations. In this work, we analyzed the evolution of the metabolism of the chromatophore of Paulinella chromatophora by in silico modeling. We asked whether genome reduction is driven by metabolic engineering strategies resulted from the interaction with the host. As its widely known, the loss of enzyme coding genes leads to metabolic network restructuring sometimes improving the production rates. In this case, the production rate of reduced-carbon in the metabolism of the chromatophore. RESULTS: We reconstructed the metabolic networks of the chromatophore of P. chromatophora CCAC 0185 and a close free-living relative, the cyanobacterium Synechococcus sp. WH 5701. We found that the evolution of free-living to host-restricted lifestyle rendered a fragile metabolic network where >80% of genes in the chromatophore are essential for metabolic functionality. Despite the lack of experimental information, the metabolic reconstruction of the chromatophore suggests that the host provides several metabolites to the endosymbiont. By using these metabolites as intracellular conditions, in silico simulations of genome evolution by gene lose recover with 77% accuracy the actual metabolic gene content of the chromatophore. Also, the metabolic model of the chromatophore allowed us to predict by flux balance analysis a maximum rate of reduced-carbon released by the endosymbiont to the host. By inspecting the central metabolism of the chromatophore and the free-living cyanobacteria we found that by improvements in the gluconeogenic pathway the metabolism of the endosymbiont uses more efficiently the carbon source for reduced-carbon production. In addition, our in silico simulations of the evolutionary process leading to the reduced metabolic network of the chromatophore showed that the predicted rate of released reduced-carbon is obtained in less than 5% of the times under a process guided by random gene deletion and genetic drift. We interpret previous findings as evidence that natural selection at holobiont level shaped the rate at which reduced-carbon is exported to the host. Finally, our model also predicts that the ABC phosphate transporter (pstSACB) which is conserved in the genome of the chromatophore of P. chromatophora strain CCAC 0185 is a necessary component to release reduced-carbon molecules to the host. CONCLUSION: Our evolutionary analysis suggests that in the case of Paulinella chromatophora natural selection at the holobiont level played a prominent role in shaping the metabolic specialization of the chromatophore. We propose that natural selection acted as a "metabolic engineer" by favoring metabolic restructurings that led to an increased release of reduced-carbon to the host.
[Mh] Termos MeSH primário: Cercozoários/citologia
Cercozoários/fisiologia
Cianobactérias/fisiologia
[Mh] Termos MeSH secundário: Evolução Biológica
Cercozoários/genética
Simulação por Computador
Cianobactérias/genética
Hexoses/metabolismo
Seleção Genética
Simbiose
Synechococcus/citologia
Synechococcus/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hexoses)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170418
[Lr] Data última revisão:
170418
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170416
[St] Status:MEDLINE
[do] DOI:10.1186/s12862-017-0947-6


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[PMID]:28371762
[Au] Autor:Jayamuthunagai J; Srisowmeya G; Chakravarthy M; Gautam P
[Ad] Endereço:Centre for Biotechnology, Anna University, Chennai 600025, Tamilnadu, India. Electronic address: jjnagai81@gmail.com.
[Ti] Título:d-Tagatose production by permeabilized and immobilized Lactobacillus plantarum using whey permeate.
[So] Source:Bioresour Technol;235:250-255, 2017 Jul.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The aim of the work is to produce d-Tagatose by direct addition of alginate immobilized Lactobacillus plantarum cells to lactose hydrolysed whey permeate. The cells were untreated and immobilized (UIC), permeabilized and immobilized (PIC) and the relative activities were compared with purified l-arabinose isomerase (l-AI) for d-galactose isomerization. Successive lactose hydrolysis by ß-galactosidase from Escherichia coli and d-galactose isomerization using l-AI from Lactobacillus plantarum was performed to investigate the in vivo production of d-tagatose in whey permeate. In whey permeate, maximum conversion of 38% and 33% (w/w) d-galactose isomerization by PIC and UIC has been obtained. 162mg/g and 141mg/g of d-tagatose production was recorded in a 48h reaction time at 50°C, pH 7.0 with 5mM Mn ion concentration in the initial substrate mixture.
[Mh] Termos MeSH primário: Lactobacillus plantarum
Soro do Leite
[Mh] Termos MeSH secundário: Aldose-Cetose Isomerases
Galactose/química
Hexoses/química
Concentração de Íons de Hidrogênio
beta-Galactosidase
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hexoses); EC 3.2.1.23 (beta-Galactosidase); EC 5.3.1.- (Aldose-Ketose Isomerases); X2RN3Q8DNE (Galactose)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170601
[Lr] Data última revisão:
170601
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170404
[St] Status:MEDLINE



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