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[PMID]: 29199984 [Au] Autor: Law A; Stergioulis A; Halavaty AS; Minasov G; Anderson WF; Kuhn ML [Ad] Endereço: Department of Chemistry and Biochemistry, San Francisco State University, USA. [Ti] Título: Structure of the Bacillus anthracis dTDP-L-rhamnose-biosynthetic enzyme dTDP-4-dehydrorhamnose reductase (RfbD). [So] Source: Acta Crystallogr F Struct Biol Commun;73(Pt 12):644-650, 2017 Dec 01. [Is] ISSN: 2053-230X [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Bacillus anthracis is the causative agent of the deadly disease Anthrax. Its use in bioterrorism and its ability to re-emerge have brought renewed interest in this organism. B. anthracis is a Gram-positive bacterium that adds L-rhamnose to its cell-wall polysaccharides using the activated donor dTDP-ß-L-rhamnose. The enzymes involved in the biosynthesis of the activated donor are absent in humans, which make them ideal targets for therapeutic development to combat pathogens. Here, the 2.65 Šresolution crystal structure of the fourth enzyme in the dTDP-ß-L-rhamnose-biosynthetic pathway from B. anthracis, dTDP-4-dehydro-ß-L-rhamnose reductase (RfbD), is presented in complex with NADP . This enzyme catalyzes the reduction of dTDP-4-dehydro-ß-L-rhamnose to dTDP-ß-L-rhamnose. Although the protein was co-crystallized in the presence of Mg , the protein lacks the conserved residues that coordinate Mg . [Mh] Termos MeSH primário: Bacillus anthracis/enzimologia Proteínas de Bactérias/química Desidrogenases de Carboidrato/química Desidrogenases de Carboidrato/metabolismo [Mh] Termos MeSH secundário: Proteínas de Bactérias/genética Proteínas de Bactérias/metabolismo Desidrogenases de Carboidrato/genética Cristalografia por Raios X Magnésio/metabolismo Modelos Moleculares NADP/química NADP/metabolismo Açúcares de Nucleosídeo Difosfato/metabolismo Conformação Proteica Multimerização Proteica Homologia Estrutural de Proteína Especificidade por Substrato Nucleotídeos de Timina/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Bacterial Proteins); 0 (Nucleoside Diphosphate Sugars); 0 (Thymine Nucleotides); 2147-59-3 (thymidine diphosphate rhamnose); 53-59-8 (NADP); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.1.133 (dTDP-4-dehydrorhamnose reductase); I38ZP9992A (Magnesium) [Em] Mês de entrada: 1802 [Cu] Atualização por classe: 180222 [Lr] Data última revisão: 180222 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 171205 [St] Status: MEDLINE [do] DOI: 10.1107/S2053230X17015746

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[PMID]: 27444326 [Au] Autor: Pandey RP; Parajuli P; Gurung RB; Sohng JK [Ad] Endereço: Institute of Biomolecule Reconstruction, Department of BT-Convergent Pharmaceutical Engineering, Sun Moon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 336-708, Republic of Korea. [Ti] Título: Donor specificity of YjiC glycosyltransferase determines the conjugation of cytosolic NDP-sugar in in vivo glycosylation reactions. [So] Source: Enzyme Microb Technol;91:26-33, 2016 Sep. [Is] ISSN: 1879-0909 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Escherichia coli BL21 (DE3) was engineered by blocking glucose-1-phosphate utilizing glucose phosphate isomerase (pgi), glucose-6-phosphate dehydrogenase (zwf) and uridylyltransferase (galU) genes to produce pool of four different rare dTDP-sugars. The cytosolic pool of dTDP-l-rhamnose, dTDP-d-viosamine, dTDP-4-amino 4,6-dideoxy-d-galactose, and dTDP-3-amino 3,6-dideoxy-d-galactose was generated by overexpressing respective dTDP-sugars biosynthesis genes from various microbial sources. A flexible glycosyltransferase YjiC, from Bacillus licheniformis DSM 13 was also overexpressed to transfer sugar moieties to 3-hydroxyl group of 3-hydroxyflavone, a core unit of flavonoids. Among four rare dTDP-sugars generated in cytosol of engineered strains, YjiC solely transferred l-rhamnose from dTDP-l-rhamnose and tuned to rhamnosyltransferase. [Mh] Termos MeSH primário: Bacillus licheniformis/enzimologia Proteínas de Bactérias/metabolismo Glicosiltransferases/metabolismo Açúcares de Nucleosídeo Difosfato/metabolismo [Mh] Termos MeSH secundário: Bacillus licheniformis/genética Proteínas de Bactérias/genética Vias Biossintéticas Citosol/metabolismo Escherichia coli/genética Escherichia coli/metabolismo Flavonoides/metabolismo Genes Bacterianos Glicosilação Glicosiltransferases/genética Proteínas Recombinantes/genética Proteínas Recombinantes/metabolismo Especificidade por Substrato Nucleotídeos de Timina/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Bacterial Proteins); 0 (Flavonoids); 0 (Nucleoside Diphosphate Sugars); 0 (Recombinant Proteins); 0 (Thymine Nucleotides); 2147-59-3 (thymidine diphosphate rhamnose); EC 2.4.- (Glycosyltransferases); ZTG9LSS5QH (3-hydroxyflavone) [Em] Mês de entrada: 1704 [Cu] Atualização por classe: 170424 [Lr] Data última revisão: 170424 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 160723 [St] Status: MEDLINE

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[PMID]: 27311566 [Au] Autor: Wahl C; Hirtz D; Elling L [Ad] Endereço: Laboratory for Biomaterials, Institute for Biotechnology and Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany. [Ti] Título: Multiplexed Capillary Electrophoresis as Analytical Tool for Fast Optimization of Multi-Enzyme Cascade Reactions - Synthesis of Nucleotide Sugars: Dedicated to Prof. Dr. Vladimir Kren on the occasion of his 60 birthday. [So] Source: Biotechnol J;11(10):1298-1308, 2016 Oct. [Is] ISSN: 1860-7314 [Cp] País de publicação: Germany [La] Idioma: eng [Ab] Resumo: Nucleotide sugars are considered as bottleneck and expensive substrates for enzymatic glycan synthesis using Leloir-glycosyltransferases. Synthesis from cheap substrates such as monosaccharides is accomplished by multi-enzyme cascade reactions. Optimization of product yields in such enzyme modules is dependent on the interplay of multiple parameters of the individual enzymes and governed by a considerable time effort when convential analytic methods like capillary electrophoresis (CE) or HPLC are applied. We here demonstrate for the first time multiplexed CE (MP-CE) as fast analytical tool for the optimization of nucleotide sugar synthesis with multi-enzyme cascade reactions. We introduce a universal separation method for nucleotides and nucleotide sugars enabling us to analyze the composition of six different enzyme modules in a high-throughput format. Optimization of parameters (T, pH, inhibitors, kinetics, cofactors and enzyme amount) employing MP-CE analysis is demonstrated for enzyme modules for the synthesis of UDP-α-D-glucuronic acid (UDP-GlcA) and UDP-α-D-galactose (UDP-Gal). In this way we achieve high space-time-yields: 1.8 g/L⋆h for UDP-GlcA and 17 g/L⋆h for UDP-Gal. The presented MP-CE methodology has the impact to be used as general analytical tool for fast optimization of multi-enzyme cascade reactions. [Mh] Termos MeSH primário: Eletroforese Capilar/métodos Enzimas/metabolismo Açúcares de Nucleosídeo Difosfato/isolamento & purificação Nucleotídeos/análise [Mh] Termos MeSH secundário: Ensaios de Triagem em Larga Escala/métodos Cinética Açúcares de Nucleosídeo Difosfato/análise Açúcares de Nucleosídeo Difosfato/biossíntese [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Enzymes); 0 (Nucleoside Diphosphate Sugars); 0 (Nucleotides) [Em] Mês de entrada: 1701 [Cu] Atualização por classe: 170119 [Lr] Data última revisão: 170119 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 160618 [St] Status: MEDLINE [do] DOI: 10.1002/biot.201600265

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[PMID]: 26965493 [Au] Autor: Liang J; Li X; Zha T; Chen Y; Hao H; Liu C; Duan R; Xiao Y; Su M; Wang X; Jing H [Ad] Endereço: National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, No.155, Changbai Road, Changpi [Ti] Título: DTDP-rhamnosyl transferase RfbF, is a newfound receptor-related regulatory protein for phage phiYe-F10 specific for Yersinia enterocolitica serotype O:3. [So] Source: Sci Rep;6:22905, 2016 Mar 11. [Is] ISSN: 2045-2322 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Bacteriophages and their hosts are continuously engaged in evolutionary competition. Here we isolated a lytic phage phiYe-F10 specific for Yersinia enterocolitica serotype O:3. We firstly described the phage receptor was regulated by DTDP-rhamnosyl transferase RfbF, encoded within the rfb cluster that was responsible for the biosynthesis of the O antigens. The deletion of DTDP-rhamnosyl transferase RfbF of wild type O:3 strain caused failure in phiYe-F10 adsorption; however, the mutation strain retained agglutination with O:3 antiserum; and complementation of its mutant converted its sensitivity to phiYe-F10. Therefore, DTDP-rhamnosyl transferase RfbF was responsible for the phage infection but did not affect recognition of Y. enterocolitica O:3 antiserum. Further, the deletions in the putative O-antigen biosynthesis protein precursor and outer membrane protein had no effect on sensitivity to phiYe-F10 infection. However, adsorption of phages onto mutant HNF10-ΔO-antigen took longer time than onto the WT, suggesting that deletion of the putative O-antigen biosynthesis protein precursor reduced the infection efficiency. [Mh] Termos MeSH primário: Bacteriófagos/genética Antígenos O/biossíntese Transferases/genética Yersinia enterocolitica/genética [Mh] Termos MeSH secundário: Sequência de Aminoácidos/genética Bacteriófagos/imunologia Elementos de DNA Transponíveis/genética Mutagênese Insercional Mutação Açúcares de Nucleosídeo Difosfato/metabolismo Antígenos O/genética Antígenos O/imunologia Sorogrupo Nucleotídeos de Timina/metabolismo Transferases/imunologia Transferases/metabolismo Yersinia enterocolitica/enzimologia Yersinia enterocolitica/imunologia [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T [Nm] Nome de substância: 0 (DNA Transposable Elements); 0 (Nucleoside Diphosphate Sugars); 0 (O Antigens); 0 (Thymine Nucleotides); 2147-59-3 (thymidine diphosphate rhamnose); EC 2.- (Transferases) [Em] Mês de entrada: 1703 [Cu] Atualização por classe: 170310 [Lr] Data última revisão: 170310 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 160312 [St] Status: MEDLINE [do] DOI: 10.1038/srep22905

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[PMID]: 26524597 [Au] Autor: de la Peña AH; Suarez A; Duong-Ly KC; Schoeffield AJ; Pizarro-Dupuy MA; Zarr M; Pineiro SA; Amzel LM; Gabelli SB [Ad] Endereço: Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America; Structural Enzymology and Thermodynamics Group, Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, Unit [Ti] Título: Structural and Enzymatic Characterization of a Nucleoside Diphosphate Sugar Hydrolase from Bdellovibrio bacteriovorus. [So] Source: PLoS One;10(11):e0141716, 2015. [Is] ISSN: 1932-6203 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Given the broad range of substrates hydrolyzed by Nudix (nucleoside diphosphate linked to X) enzymes, identification of sequence and structural elements that correctly predict a Nudix substrate or characterize a family is key to correctly annotate the myriad of Nudix enzymes. Here, we present the structure determination and characterization of Bd3179 -- a Nudix hydrolase from Bdellovibrio bacteriovorus-that we show localized in the periplasmic space of this obligate Gram-negative predator. We demonstrate that the enzyme is a nucleoside diphosphate sugar hydrolase (NDPSase) and has a high degree of sequence and structural similarity to a canonical ADP-ribose hydrolase and to a nucleoside diphosphate sugar hydrolase (1.4 and 1.3 Å Cα RMSD respectively). Examination of the structural elements conserved in both types of enzymes confirms that an aspartate-X-lysine motif on the C-terminal helix of the α-ß-α NDPSase fold differentiates NDPSases from ADPRases. [Mh] Termos MeSH primário: Proteínas de Bactérias/química Proteínas de Bactérias/metabolismo Bdellovibrio/enzimologia Pirofosfatases/química Pirofosfatases/metabolismo [Mh] Termos MeSH secundário: Proteínas de Bactérias/genética Bdellovibrio/genética Domínio Catalítico Clonagem Molecular Modelos Moleculares Açúcares de Nucleosídeo Difosfato/metabolismo Periplasma/metabolismo Estrutura Terciária de Proteína Pirofosfatases/genética Homologia de Sequência de Aminoácidos [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S. [Nm] Nome de substância: 0 (Bacterial Proteins); 0 (Nucleoside Diphosphate Sugars); EC 3.6.1.- (Pyrophosphatases); EC 3.6.1.- (nudix hydrolases) [Em] Mês de entrada: 1606 [Cu] Atualização por classe: 170220 [Lr] Data última revisão: 170220 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 151103 [St] Status: MEDLINE [do] DOI: 10.1371/journal.pone.0141716

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[PMID]: 26289554 [Au] Autor: Peltier-Pain P; Singh S; Thorson JS [Ad] Endereço: Pharmaceutical Sciences Division, University of Wisconsin-Madison, 777 Highland Avenue, Madison, WI, 53705, USA. [Ti] Título: Characterization of Early Enzymes Involved in TDP-Aminodideoxypentose Biosynthesis en Route to Indolocarbazole AT2433. [So] Source: Chembiochem;16(15):2141-6, 2015 Oct 12. [Is] ISSN: 1439-7633 [Cp] País de publicação: Germany [La] Idioma: eng [Ab] Resumo: The characterization of TDP-α-D-glucose dehydrogenase (AtmS8), TDP-α-D-glucuronic acid decarboxylase (AtmS9), and TDP-4-keto-α-D-xylose 2,3-dehydratase (AtmS14), involved in Actinomadura melliaura AT2433 aminodideoxypentose biosynthesis, is reported. This study provides the first biochemical evidence that both deoxypentose and deoxyhexose biosynthetic pathways share common strategies for sugar 2,3-dehydration/reduction and implicates the sugar nucleotide base specificity of AtmS14 as a potential mechanism for sugar nucleotide commitment to secondary metabolism. In addition, a re-evaluation of the AtmS9 homologue involved in calicheamicin aminodeoxypentose biosynthesis (CalS9) reveals that CalS9 catalyzes UDP-4-keto-α-D-xylose as the predominant product, rather than UDP-α-D-xylose as previously reported. Cumulatively, this work provides additional fundamental insights regarding the biosynthesis of novel pentoses attached to complex bacterial secondary metabolites. [Mh] Termos MeSH primário: Carbazóis/metabolismo Glucose 1-Desidrogenase/metabolismo Glutamato Descarboxilase/metabolismo Hidroliases/metabolismo Açúcares de Nucleosídeo Difosfato/biossíntese [Mh] Termos MeSH secundário: Carbazóis/química Glucose 1-Desidrogenase/química Glutamato Descarboxilase/química Hidroliases/química Estrutura Molecular Espectroscopia de Prótons por Ressonância Magnética [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S. [Nm] Nome de substância: 0 (Carbazoles); 0 (Nucleoside Diphosphate Sugars); EC 1.1.1.47 (Glucose 1-Dehydrogenase); EC 4.1.1.15 (Glutamate Decarboxylase); EC 4.2.1.- (Hydro-Lyases) [Em] Mês de entrada: 1607 [Cu] Atualização por classe: 170220 [Lr] Data última revisão: 170220 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 150821 [St] Status: MEDLINE [do] DOI: 10.1002/cbic.201500365

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[PMID]: 26279371 [Au] Autor: Eastwood H; Xia F; Lo MC; Zhou J; Jordan JB; McCarter J; Barnhart WW; Gahm KH [Ad] Endereço: Department of Molecular Structure & Characterization, Amgen, Inc., Thousand Oaks, CA 91320, United States. Electronic address: heathere@amgen.com. [Ti] Título: Development of a nucleotide sugar purification method using a mixed mode column & mass spectrometry detection. [So] Source: J Pharm Biomed Anal;115:402-9, 2015 Nov 10. [Is] ISSN: 1873-264X [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Analysis of nucleotide sugars, nucleoside di- and triphosphates and sugar-phosphates is an essential step in the process of understanding enzymatic pathways. A facile and rapid separation method was developed to analyze these compounds present in an enzymatic reaction mixture utilized to produce nucleotide sugars. The Primesep SB column explored in this study utilizes hydrophobic interactions as well as electrostatic interactions with the phosphoric portion of the nucleotide sugars. Ammonium formate buffer was selected due to its compatibility with mass spectrometry. Negative ion mode mass spectrometry was adopted for detection of the sugar phosphate (fucose-1-phophate), as the compound is not amenable to UV detection. Various mobile phase conditions such as pH, buffer concentration and organic modifier were explored. The semi-preparative separation method was developed to prepare 30mg of the nucleotide sugar. (19)F NMR was utilized to determine purity of the purified fluorinated nucleotide sugar. The collected nucleotide sugar was found to be 99% pure. [Mh] Termos MeSH primário: Carboidratos/análise Cromatografia Líquida de Alta Pressão Espectrometria de Massas Nucleotídeos/análise [Mh] Termos MeSH secundário: Tampões (Química) Fucose/análogos & derivados Fucose/análise Hexosefosfatos/análise Concentração de Íons de Hidrogênio Interações Hidrofóbicas e Hidrofílicas Espectroscopia de Ressonância Magnética Estrutura Molecular Açúcares de Nucleosídeo Difosfato/análise Solventes/química Eletricidade Estática Fosfatos Açúcares/análise [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Buffers); 0 (Carbohydrates); 0 (Hexosephosphates); 0 (Nucleoside Diphosphate Sugars); 0 (Nucleotides); 0 (Solvents); 0 (Sugar Phosphates); 28553-11-9 (fucopyranosyl phosphate); 28RYY2IV3F (Fucose) [Em] Mês de entrada: 1607 [Cu] Atualização por classe: 171116 [Lr] Data última revisão: 171116 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 150818 [St] Status: MEDLINE

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[PMID]: 26278404 [Au] Autor: van der Beek SL; Le Breton Y; Ferenbach AT; Chapman RN; van Aalten DM; Navratilova I; Boons GJ; McIver KS; van Sorge NM; Dorfmueller HC [Ad] Endereço: University Medical Center Utrecht, Medical Microbiology, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands. [Ti] Título: GacA is essential for Group A Streptococcus and defines a new class of monomeric dTDP-4-dehydrorhamnose reductases (RmlD). [So] Source: Mol Microbiol;98(5):946-62, 2015 Dec. [Is] ISSN: 1365-2958 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: The sugar nucleotide dTDP-L-rhamnose is critical for the biosynthesis of the Group A Carbohydrate, the molecular signature and virulence determinant of the human pathogen Group A Streptococcus (GAS). The final step of the four-step dTDP-L-rhamnose biosynthesis pathway is catalyzed by dTDP-4-dehydrorhamnose reductases (RmlD). RmlD from the Gram-negative bacterium Salmonella is the only structurally characterized family member and requires metal-dependent homo-dimerization for enzymatic activity. Using a biochemical and structural biology approach, we demonstrate that the only RmlD homologue from GAS, previously renamed GacA, functions in a novel monomeric manner. Sequence analysis of 213 Gram-negative and Gram-positive RmlD homologues predicts that enzymes from all Gram-positive species lack a dimerization motif and function as monomers. The enzymatic function of GacA was confirmed through heterologous expression of gacA in a S. mutans rmlD knockout, which restored attenuated growth and aberrant cell division. Finally, analysis of a saturated mutant GAS library using Tn-sequencing and generation of a conditional-expression mutant identified gacA as an essential gene for GAS. In conclusion, GacA is an essential monomeric enzyme in GAS and representative of monomeric RmlD enzymes in Gram-positive bacteria and a subset of Gram-negative bacteria. These results will help future screens for novel inhibitors of dTDP-L-rhamnose biosynthesis. [Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo Desidrogenases de Carboidrato/genética Desidrogenases de Carboidrato/metabolismo Streptococcus pyogenes/enzimologia [Mh] Termos MeSH secundário: Sequência de Aminoácidos Proteínas de Bactérias/química Proteínas de Bactérias/genética Desidrogenases de Carboidrato/química Carboidratos Epimerases/metabolismo Clonagem Molecular Bactérias Gram-Positivas/enzimologia Sequenciamento de Nucleotídeos em Larga Escala Seres Humanos Modelos Moleculares Mutação Açúcares de Nucleosídeo Difosfato/biossíntese Estrutura Terciária de Proteína Ramnose/análogos & derivados Ramnose/biossíntese Ramnose/metabolismo Alinhamento de Sequência Streptococcus pyogenes/genética Nucleotídeos de Timina/biossíntese Nucleotídeos de Timina/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T [Nm] Nome de substância: 0 (Bacterial Proteins); 0 (GacA protein, Bacteria); 0 (Nucleoside Diphosphate Sugars); 0 (Thymine Nucleotides); 0 (dTDP-4-ketorhamnose); 2147-59-3 (thymidine diphosphate rhamnose); EC 1.1.- (Carbohydrate Dehydrogenases); EC 1.1.1.133 (dTDP-4-dehydrorhamnose reductase); EC 5.1.3.- (Carbohydrate Epimerases); QN34XC755A (Rhamnose) [Em] Mês de entrada: 1610 [Cu] Atualização por classe: 170922 [Lr] Data última revisão: 170922 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 150818 [St] Status: MEDLINE [do] DOI: 10.1111/mmi.13169

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[PMID]: 25825127 [Au] Autor: Eugster MR; Morax LS; Hüls VJ; Huwiler SG; Leclercq A; Lecuit M; Loessner MJ [Ad] Endereço: Institute of Food, Nutrition and Health, ETH Zurich, CH-8092, Zurich, Switzerland. [Ti] Título: Bacteriophage predation promotes serovar diversification in Listeria monocytogenes. [So] Source: Mol Microbiol;97(1):33-46, 2015 Jul. [Is] ISSN: 1365-2958 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Listeria monocytogenes is a bacterial pathogen classified into distinct serovars (SVs) based on somatic and flagellar antigens. To correlate phenotype with genetic variation, we analyzed the wall teichoic acid (WTA) glycosylation genes of SV 1/2, 3 and 7 strains, which differ in decoration of the ribitol-phosphate backbone with N-acetylglucosamine (GlcNAc) and/or rhamnose. Inactivation of lmo1080 or the dTDP-l-rhamnose biosynthesis genes rmlACBD (lmo1081-1084) resulted in loss of rhamnose, whereas disruption of lmo1079 led to GlcNAc deficiency. We found that all SV 3 and 7 strains actually originate from a SV 1/2 background, as a result of small mutations in WTA rhamnosylation and/or GlcNAcylation genes. Genetic complementation of different SV 3 and 7 isolates using intact alleles fully restored a characteristic SV 1/2 WTA carbohydrate pattern, including antisera reactions and phage adsorption. Intriguingly, phage-resistant L. monocytogenes EGDe (SV 1/2a) isolates featured the same glycosylation gene mutations and were serotyped as SV 3 or 7 respectively. Again, genetic complementation restored both carbohydrate antigens and phage susceptibility. Taken together, our data demonstrate that L. monocytogenes SV 3 and 7 originate from point mutations in glycosylation genes, and we show that phage predation represents a major driving force for serovar diversification and evolution of L. monocytogenes. [Mh] Termos MeSH primário: Bacteriófagos/fisiologia Parede Celular/química Listeria monocytogenes/classificação Listeria monocytogenes/virologia Ácidos Teicoicos/genética [Mh] Termos MeSH secundário: Acetilglucosamina/metabolismo Bacteriófagos/genética Parede Celular/genética Parede Celular/metabolismo Teste de Complementação Genética Variação Genética Glicosilação Listeria monocytogenes/genética Dados de Sequência Molecular Açúcares de Nucleosídeo Difosfato/genética Fenótipo Mutação Puntual Ramnose/metabolismo Sorogrupo Sorotipagem Ácidos Teicoicos/metabolismo Nucleotídeos de Timina/genética [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Nucleoside Diphosphate Sugars); 0 (Teichoic Acids); 0 (Thymine Nucleotides); 2147-59-3 (thymidine diphosphate rhamnose); QN34XC755A (Rhamnose); V956696549 (Acetylglucosamine) [Em] Mês de entrada: 1604 [Cu] Atualização por classe: 150625 [Lr] Data última revisão: 150625 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 150401 [St] Status: MEDLINE [do] DOI: 10.1111/mmi.13009

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[PMID]: 25418063 [Au] Autor: Ko Y; Ruszczycky MW; Choi SH; Liu HW [Ad] Endereço: Division of Medicinal Chemistry, College of Pharmacy and Department of Chemistry, University of Texas at Austin, Austin, TX 78712 (USA). [Ti] Título: Mechanistic studies of the radical S-adenosylmethionine enzyme DesII with TDP-D-fucose. [So] Source: Angew Chem Int Ed Engl;54(3):860-3, 2015 Jan 12. [Is] ISSN: 1521-3773 [Cp] País de publicação: Germany [La] Idioma: eng [Ab] Resumo: DesII is a radical S-adenosylmethionine (SAM) enzyme that catalyzes the C4-deamination of TDP-4-amino-4,6-dideoxyglucose through a C3 radical intermediate. However, if the C4 amino group is replaced with a hydroxy group (to give TDP-quinovose), the hydroxy group at C3 is oxidized to a ketone with no C4-dehydration. It is hypothesized that hyperconjugation between the C4 C-N/O bond and the partially filled p orbital at C3 of the radical intermediate modulates the degree to which elimination competes with dehydrogenation. To investigate this hypothesis, the reaction of DesII with the C4-epimer of TDP-quinovose (TDP-fucose) was examined. The reaction primarily results in the formation of TDP-6-deoxygulose and likely regeneration of TDP-fucose. The remainder of the substrate radical partitions roughly equally between C3-dehydrogenation and C4-dehydration. Thus, changing the stereochemistry at C4 permits a more balanced competition between elimination and dehydrogenation. [Mh] Termos MeSH primário: Hidrolases/metabolismo Açúcares de Nucleosídeo Difosfato/metabolismo Nucleotídeos de Timina/metabolismo [Mh] Termos MeSH secundário: Biocatálise Domínio Catalítico Espectroscopia de Ressonância de Spin Eletrônica Radicais Livres/química Radicais Livres/metabolismo Hidrolases/química Oxirredução Estereoisomerismo Streptomyces/enzimologia Especificidade por Substrato [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T [Nm] Nome de substância: 0 (Free Radicals); 0 (Nucleoside Diphosphate Sugars); 0 (Thymine Nucleotides); 0 (thymidine diphosphate fucose); EC 3.- (Hydrolases); EC 3.3.1.2 (adenosylmethionine hydrolase) [Em] Mês de entrada: 1603 [Cu] Atualização por classe: 161019 [Lr] Data última revisão: 161019 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 141125 [St] Status: MEDLINE [do] DOI: 10.1002/anie.201409540

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