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[PMID]:26913738
[Au] Autor:Brixius-Anderko S; Hannemann F; Ringle M; Khatri Y; Bernhardt R
[Ad] Endereço:Department of Biochemistry, Saarland University, Saarbrücken, Germany.
[Ti] Título:An indole-deficient Escherichia coli strain improves screening of cytochromes P450 for biotechnological applications.
[So] Source:Biotechnol Appl Biochem;64(3):315-326, 2017 May.
[Is] ISSN:1470-8744
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Escherichia coli has developed into an attractive organism for heterologous cytochrome P450 production, but, in some cases, was restricted as a host in view of a screening of orphan cytochromes P450 or mutant libraries in the context of molecular evolution due to the formation of the cytochrome P450 inhibitor indole by the enzyme tryptophanase (TnaA). To overcome this effect, we disrupted the tnaA gene locus of E. coli C43(DE3) and evaluated the new strain for whole-cell substrate conversions with three indole-sensitive cytochromes P450, myxobacterial CYP264A1, and CYP109D1 as well as bovine steroidogenic CYP21A2. For purified CYP264A1 and CYP21A2, the half maximal inhibitory indole concentration was determined to be 140 and 500 µM, which is within the physiological concentration range occurring during cultivation of E. coli in complex medium. Biotransformations with C43(DE3)_∆tnaA achieved a 30% higher product formation in the case of CYP21A2 and an even fourfold increase with CYP264A1 compared with C43(DE3) cells. In whole-cell conversion based on CYP109D1, which converts indole to indigo, we could successfully avoid this reaction. Results in microplate format indicate that our newly designed strain is a suitable host for a fast and efficient screening of indole-influenced cytochromes P450 in complex medium.
[Mh] Termos MeSH primário: Inibidores das Enzimas do Citocromo P-450
Sistema Enzimático do Citocromo P-450/biossíntese
Proteínas de Escherichia coli/genética
Escherichia coli
Deleção de Genes
Indóis
Triptofanase/deficiência
[Mh] Termos MeSH secundário: Animais
Bovinos
Sistema Enzimático do Citocromo P-450/genética
Escherichia coli/genética
Escherichia coli/metabolismo
Proteínas Recombinantes/biossíntese
Proteínas Recombinantes/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cytochrome P-450 Enzyme Inhibitors); 0 (Escherichia coli Proteins); 0 (Indoles); 0 (Recombinant Proteins); 8724FJW4M5 (indole); 9035-51-2 (Cytochrome P-450 Enzyme System); EC 4.1.99.1 (Tryptophanase)
[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:160226
[St] Status:MEDLINE
[do] DOI:10.1002/bab.1488


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[PMID]:27978427
[Au] Autor:Skye SM; Hazen SL
[Ad] Endereço:Department of Cellular & Molecular Medicine, Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
[Ti] Título:Microbial Modulation of a Uremic Toxin.
[So] Source:Cell Host Microbe;20(6):691-692, 2016 Dec 14.
[Is] ISSN:1934-6069
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this issue of Cell Host & Microbe, Devlin et al. (2016) identify a family of tryptophanases encoded by members of the human gut microbiome and demonstrate that levels of the uremic toxin indoxyl sulfate can be modulated in vivo by altering the abundance of bacteria harboring tryptophanase activity.
[Mh] Termos MeSH primário: Microbioma Gastrointestinal/fisiologia
Indicã/metabolismo
Indicã/toxicidade
Uremia/metabolismo
[Mh] Termos MeSH secundário: Animais
Bactérias/enzimologia
Bactérias/metabolismo
Toxinas Bacterianas/metabolismo
Evolução Biológica
Doenças Cardiovasculares/metabolismo
Dieta
Seres Humanos
Rim/metabolismo
Fígado/metabolismo
Simbiose
Triptofanase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Toxins); EC 4.1.99.1 (Tryptophanase); N187WK1Y1J (Indican)
[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:161216
[St] Status:MEDLINE


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[PMID]:27916477
[Au] Autor:Devlin AS; Marcobal A; Dodd D; Nayfach S; Plummer N; Meyer T; Pollard KS; Sonnenburg JL; Fischbach MA
[Ad] Endereço:Department of Bioengineering and Therapeutic Sciences and California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, CA 94143, USA.
[Ti] Título:Modulation of a Circulating Uremic Solute via Rational Genetic Manipulation of the Gut Microbiota.
[So] Source:Cell Host Microbe;20(6):709-715, 2016 Dec 14.
[Is] ISSN:1934-6069
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Renal disease is growing in prevalence and has striking co-morbidities with metabolic and cardiovascular disease. Indoxyl sulfate (IS) is a toxin that accumulates in plasma when kidney function declines and contributes to the progression of chronic kidney disease. IS derives exclusively from the gut microbiota. Bacterial tryptophanases convert tryptophan to indole, which is absorbed and modified by the host to produce IS. Here, we identify a widely distributed family of tryptophanases in the gut commensal Bacteroides and find that deleting this gene eliminates the production of indole in vitro. By altering the status or abundance of the Bacteroides tryptophanase, we can modulate IS levels in gnotobiotic mice and in the background of a conventional murine gut community. Our results demonstrate that it is possible to control host IS levels by targeting the microbiota and suggest a possible strategy for treating renal disease.
[Mh] Termos MeSH primário: Microbioma Gastrointestinal/fisiologia
Trato Gastrointestinal/microbiologia
Indicã/metabolismo
Indicã/toxicidade
[Mh] Termos MeSH secundário: Ração Animal
Animais
Bactérias/efeitos dos fármacos
Bactérias/enzimologia
Bactérias/genética
Bactérias/metabolismo
Bacteroides/enzimologia
Bacteroides/genética
Dieta
Modelos Animais de Doenças
Progressão da Doença
Microbioma Gastrointestinal/genética
Engenharia Genética
Vida Livre de Germes/efeitos dos fármacos
Seres Humanos
Indóis/metabolismo
Metagenoma
Camundongos
Microbiota/genética
Insuficiência Renal Crônica
Toxinas Biológicas/biossíntese
Toxinas Biológicas/urina
Triptofano/metabolismo
Triptofanase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Indoles); 0 (Toxins, Biological); 0 (uremia middle molecule toxins); 8724FJW4M5 (indole); 8DUH1N11BX (Tryptophan); EC 4.1.99.1 (Tryptophanase); N187WK1Y1J (Indican)
[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:161206
[St] Status:MEDLINE


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[PMID]:27158906
[Au] Autor:Rothhammer V; Mascanfroni ID; Bunse L; Takenaka MC; Kenison JE; Mayo L; Chao CC; Patel B; Yan R; Blain M; Alvarez JI; Kébir H; Anandasabapathy N; Izquierdo G; Jung S; Obholzer N; Pochet N; Clish CB; Prinz M; Prat A; Antel J; Quintana FJ
[Ad] Endereço:Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
[Ti] Título:Type I interferons and microbial metabolites of tryptophan modulate astrocyte activity and central nervous system inflammation via the aryl hydrocarbon receptor.
[So] Source:Nat Med;22(6):586-97, 2016 Jun.
[Is] ISSN:1546-170X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Astrocytes have important roles in the central nervous system (CNS) during health and disease. Through genome-wide analyses we detected a transcriptional response to type I interferons (IFN-Is) in astrocytes during experimental CNS autoimmunity and also in CNS lesions from patients with multiple sclerosis (MS). IFN-I signaling in astrocytes reduces inflammation and experimental autoimmune encephalomyelitis (EAE) disease scores via the ligand-activated transcription factor aryl hydrocarbon receptor (AHR) and the suppressor of cytokine signaling 2 (SOCS2). The anti-inflammatory effects of nasally administered interferon (IFN)-ß are partly mediated by AHR. Dietary tryptophan is metabolized by the gut microbiota into AHR agonists that have an effect on astrocytes to limit CNS inflammation. EAE scores were increased following ampicillin treatment during the recovery phase, and CNS inflammation was reduced in antibiotic-treated mice by supplementation with the tryptophan metabolites indole, indoxyl-3-sulfate, indole-3-propionic acid and indole-3-aldehyde, or the bacterial enzyme tryptophanase. In individuals with MS, the circulating levels of AHR agonists were decreased. These findings suggest that IFN-Is produced in the CNS function in combination with metabolites derived from dietary tryptophan by the gut flora to activate AHR signaling in astrocytes and suppress CNS inflammation.
[Mh] Termos MeSH primário: Astrócitos/imunologia
Encefalomielite Autoimune Experimental/imunologia
Microbioma Gastrointestinal
Interferon Tipo I/imunologia
Esclerose Múltipla/imunologia
Receptores de Hidrocarboneto Arílico/imunologia
Linfócitos T/imunologia
Triptofano/metabolismo
[Mh] Termos MeSH secundário: Animais
Estudos de Casos e Controles
Proliferação Celular
Sistema Nervoso Central/imunologia
Sistema Nervoso Central/metabolismo
Quimiocina CCL2/metabolismo
Imunoprecipitação da Cromatina
Cromatografia Líquida de Alta Pressão
Encefalomielite Autoimune Experimental/metabolismo
Imunofluorescência
Perfilação da Expressão Gênica
Técnicas de Silenciamento de Genes
Proteína Glial Fibrilar Ácida/metabolismo
Seres Humanos
Immunoblotting
Indicã/urina
Indóis/metabolismo
Inflamação
Interferon beta/farmacologia
Lactobacillus reuteri
Camundongos
Camundongos Knockout
Esclerose Múltipla/metabolismo
Proteínas de Resistência a Myxovirus/metabolismo
Óxido Nítrico Sintase Tipo II/metabolismo
Imagem Óptica
Reação em Cadeia da Polimerase
Receptor de Interferon alfa e beta/genética
Receptores de Hidrocarboneto Arílico/metabolismo
Fator de Transcrição STAT1/metabolismo
Serotonina
Proteínas Supressoras da Sinalização de Citocinas
Triptofanase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (CCL2 protein, human); 0 (Chemokine CCL2); 0 (Glial Fibrillary Acidic Protein); 0 (Ifnar1 protein, mouse); 0 (Indoles); 0 (Interferon Type I); 0 (MX1 protein, human); 0 (Myxovirus Resistance Proteins); 0 (Receptors, Aryl Hydrocarbon); 0 (STAT1 Transcription Factor); 0 (STAT1 protein, human); 0 (Socs2 protein, mouse); 0 (Suppressor of Cytokine Signaling Proteins); 156986-95-7 (Receptor, Interferon alpha-beta); 333DO1RDJY (Serotonin); 77238-31-4 (Interferon-beta); 7FN04C32UO (indole-3-carbaldehyde); 830-96-6 (indolepropionic acid); 8724FJW4M5 (indole); 8DUH1N11BX (Tryptophan); EC 1.14.13.39 (NOS2 protein, human); EC 1.14.13.39 (Nitric Oxide Synthase Type II); EC 4.1.99.1 (Tryptophanase); N187WK1Y1J (Indican)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170807
[Lr] Data última revisão:
170807
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160510
[St] Status:MEDLINE
[do] DOI:10.1038/nm.4106


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[PMID]:26989252
[Au] Autor:Sicoli G; Mouesca JM; Zeppieri L; Amara P; Martin L; Barra AL; Fontecilla-Camps JC; Gambarelli S; Nicolet Y
[Ad] Endereço:Université Grenoble-Alpes, Institut Nanosciences et Cryogénie (INAC)-Service de Chimie Inorganique et Biologique (SCIB)/Laboratoire de Résonance Magnétique (LRM), F-38000 Grenoble, France. Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), INAC-SCIB/LRM, F-38000 Grenoble, France.
[Ti] Título:Fine-tuning of a radical-based reaction by radical S-adenosyl-L-methionine tryptophan lyase.
[So] Source:Science;351(6279):1320-3, 2016 Mar 18.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The radical S-adenosyl-L-methionine tryptophan lyase NosL converts L-tryptophan into 3-methylindolic acid, which is a precursor in the synthesis of the thiopeptide antibiotic nosiheptide. Using electron paramagnetic resonance spectroscopy and multiple L-tryptophan isotopologues, we trapped and characterized radical intermediates that indicate a carboxyl fragment migration mechanism for NosL. This is in contrast to a proposed fragmentation-recombination mechanism that implied Cα-Cß bond cleavage of L-tryptophan. Although NosL resembles related tyrosine lyases, subtle substrate motions in its active site are responsible for a fine-tuned radical chemistry, which selects the Cα-C bond for disruption. This mechanism highlights evolutionary adaptation to structural constraints in proteins as a route to alternative enzyme function.
[Mh] Termos MeSH primário: Carbono-Carbono Liases/química
Indóis/metabolismo
S-Adenosilmetionina/química
Streptomyces/enzimologia
Triptofano/química
Triptofanase/química
[Mh] Termos MeSH secundário: Domínio Catalítico
Espectroscopia de Ressonância de Spin Eletrônica
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Indoles); 7LP2MPO46S (S-Adenosylmethionine); 8DUH1N11BX (Tryptophan); EC 4.1.- (Carbon-Carbon Lyases); EC 4.1.- (S-adenosyl-L-methionine tryptophan lyase, Streptomyces actuosus); EC 4.1.99.1 (Tryptophanase)
[Em] Mês de entrada:1604
[Cu] Atualização por classe:160318
[Lr] Data última revisão:
160318
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160319
[St] Status:MEDLINE
[do] DOI:10.1126/science.aad8995


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[PMID]:26989237
[Au] Autor:Bridwell-Rabb J; Drennan CL
[Ad] Endereço:Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. jb_rabb@mit.edu cdrennan@mit.edu.
[Ti] Título:BIOCHEMISTRY. A radically unexpected mechanism.
[So] Source:Science;351(6279):1266-7, 2016 Mar 18.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Carbono-Carbono Liases/química
Indóis/metabolismo
S-Adenosilmetionina/química
Streptomyces/enzimologia
Triptofano/química
Triptofanase/química
[Pt] Tipo de publicação:COMMENT; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Indoles); 7LP2MPO46S (S-Adenosylmethionine); 8DUH1N11BX (Tryptophan); EC 4.1.- (Carbon-Carbon Lyases); EC 4.1.- (S-adenosyl-L-methionine tryptophan lyase, Streptomyces actuosus); EC 4.1.99.1 (Tryptophanase)
[Em] Mês de entrada:1604
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160319
[St] Status:MEDLINE
[do] DOI:10.1126/science.aaf4942


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[PMID]:26586366
[Au] Autor:Winnicka E; Szymanska J; Kanska M
[Ad] Endereço:a Department of Chemistry , University of Warsaw , Warsaw , Poland.
[Ti] Título:Synthesis of deuterium-labelled halogen derivatives of L-tryptophan catalysed by tryptophanase.
[So] Source:Isotopes Environ Health Stud;52(3):231-8, 2016 Jun.
[Is] ISSN:1477-2639
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The isotopomers of halogen derivatives of l-tryptophan (l-Trp) (4'-F-, 7'-F-, 5'-Cl- and 7'-Br-l-Trp), specifically labelled with deuterium in α-position of the side chain, were obtained by enzymatic coupling of the corresponding halogenated derivatives of indole with S-methyl-l-cysteine in (2)H2O, catalysed by enzyme tryptophanase (EC 4.1.99.1). The positional deuterium enrichment of the resulting tryptophan derivatives was controlled using (1)H NMR. In accordance with the mechanism of the lyase reaction, a 100% deuterium labelling was observed in the α-position; the chemical yields were between 23 and 51%. Furthermore, ß-F-l-alanine, synthesized from ß-F-pyruvic acid by the l-alanine dehydrogenase reaction, has been tested as a coupling agent to obtain the halogenated deuterium-labelled derivatives of l-Trp. The chemical yield (∼30%) corresponded to that as observed with S-methyl-l-cysteine but the deuterium label was only 63%, probably due to the use of a not completely deuterated incubation medium.
[Mh] Termos MeSH primário: Alanina Desidrogenase/química
Deutério
Halogênios/química
Compostos Radiofarmacêuticos/síntese química
Triptofano/análogos & derivados
Triptofanase/química
[Mh] Termos MeSH secundário: Bacillus subtilis/enzimologia
Biocatálise
Escherichia coli/enzimologia
Marcação por Isótopo
Compostos Radiofarmacêuticos/química
Triptofano/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Halogens); 0 (Radiopharmaceuticals); 8DUH1N11BX (Tryptophan); AR09D82C7G (Deuterium); EC 1.4.1.1 (Alanine Dehydrogenase); EC 4.1.99.1 (Tryptophanase)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170213
[Lr] Data última revisão:
170213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151121
[St] Status:MEDLINE
[do] DOI:10.1080/10256016.2016.1105801


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[PMID]:26410393
[Au] Autor:Bryk G; Coronel MZ; Lugones C; Mandalunis P; Rio ME; Gualtieri AF; de Portela ML; Zeni SN
[Ad] Endereço:General and Oral Biochemistry Department, School of Dentistry, Buenos Aires University (UBA), Av. Córdoba 2351-8vo. Piso (1120), Buenos Aires, Argentina.
[Ti] Título:Effect of a mixture of GOS/FOS on calcium absorption and retention during recovery from protein malnutrition: experimental model in growing rats.
[So] Source:Eur J Nutr;55(8):2445-2458, 2016 Dec.
[Is] ISSN:1436-6215
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:INTRODUCTION: During growth, protein deprivation impairs epiphyseal growth plate (EGP) height, bone volume (BV) and endochondral ossification. During catch-up growth, Ca availability becomes essential to ensure the extra amount needed to achieve optimal peak bone mass and strength. GOS and FOS improve mineral absorption in the colon. PURPOSE: The effect of a mixture of GOS/FOS 9:1 added to a 0.5 %Ca (NCa) and a 0.3 %Ca (LCa) diets on Ca, P and Mg absorptions and bone mineralization, density and structure using an experimental model of growing rats recovering from early protein malnutrition was investigated. METHODS: To induce protein malnutrition, rats were fed a low protein diet: 4 % (LPD) during 1 week and then were randomly assigned to recovery groups (R) until day 50 (T = 50) as follows: R0.5 %: NCa; RP0.5 %: NCa + 5.3 % GOS/FOS ; R0.3 %: LCa and RP0.3 %: LCa + 5.3 % GOS/FOS . Control groups received the 0.5 %Ca or 0.3 %Ca diet from weaning until day 40 or 50. RESULTS: Body weight and length increased in C groups throughout the study; both were arrested in all R during LPD consumption and increased immediately after re-feeding. Independently of dietary Ca content, LS counts, ß-glucosidase and Ca, P and Mg absorption increased, whereas cecum pH, ß-glucuronidase, urease and tryptophanase decreased in RP0.5 %: and RP0.3 %: as compared to the other studied groups (p < 0.01). Prebiotic consumption decreased CTX levels and increased femur Ca, Mg and P contents, total skeleton bone mineral content, proximal tibia and spine BMD, BV, EGP height and hypertrophic zone thickness, stiffness and elastic modulus as compared to recovery groups fed the prebiotic-free diets. CONCLUSION: Under the present experimental conditions, GOS/FOS mixture induced colonic positive effects, which increased Ca, P and Mg absorption. Thus, consuming the prebiotic-containing diet resulted in an extra amount of minerals that improved bone development in growing rats recovering from protein malnutrition.
[Mh] Termos MeSH primário: Cálcio na Dieta/farmacocinética
Oligossacarídeos/administração & dosagem
Desnutrição Proteico-Calórica/tratamento farmacológico
Trissacarídeos/administração & dosagem
[Mh] Termos MeSH secundário: Animais
Disponibilidade Biológica
Peso Corporal
Densidade Óssea/efeitos dos fármacos
Desenvolvimento Ósseo/efeitos dos fármacos
Calcificação Fisiológica/efeitos dos fármacos
Cálcio na Dieta/administração & dosagem
Cálcio na Dieta/sangue
Ceco/efeitos dos fármacos
Ceco/metabolismo
Dieta
Fezes/química
Fêmur/efeitos dos fármacos
Fêmur/fisiologia
Glucuronidase/metabolismo
Lâmina de Crescimento/efeitos dos fármacos
Lâmina de Crescimento/fisiologia
Absorção Intestinal
Magnésio/administração & dosagem
Magnésio/sangue
Magnésio/farmacocinética
Masculino
Oligossacarídeos/sangue
Oligossacarídeos/farmacocinética
Fósforo na Dieta/administração & dosagem
Fósforo na Dieta/sangue
Fósforo na Dieta/farmacocinética
Prebióticos/administração & dosagem
Desnutrição Proteico-Calórica/sangue
Ratos
Ratos Wistar
Trissacarídeos/sangue
Trissacarídeos/farmacocinética
Triptofanase/metabolismo
Urease/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Calcium, Dietary); 0 (Oligosaccharides); 0 (Phosphorus, Dietary); 0 (Prebiotics); 0 (Trisaccharides); 0 (fructooligosaccharide); 6587-31-1 (4'-galactooligosaccharide); EC 3.2.1.31 (Glucuronidase); EC 3.5.1.5 (Urease); EC 4.1.99.1 (Tryptophanase); I38ZP9992A (Magnesium)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150928
[St] Status:MEDLINE


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[PMID]:26627645
[Au] Autor:Green K; Qasim N; Gdaelvsky G; Kogan A; Goldgur Y; Parola AH; Lotan O; Almog O
[Ad] Endereço:Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, PO Box 105, Beer Sheva 84105, Israel.
[Ti] Título:A structural view of the dissociation of Escherichia coli tryptophanase.
[So] Source:Acta Crystallogr D Biol Crystallogr;71(Pt 12):2364-71, 2015 Dec 01.
[Is] ISSN:1399-0047
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Tryptophanase (Trpase) is a pyridoxal 5'-phosphate (PLP)-dependent homotetrameric enzyme which catalyzes the degradation of L-tryptophan. Trpase is also known for its cold lability, which is a reversible loss of activity at low temperature (2°C) that is associated with the dissociation of the tetramer. Escherichia coli Trpase dissociates into dimers, while Proteus vulgaris Trpase dissociates into monomers. As such, this enzyme is an appropriate model to study the protein-protein interactions and quaternary structure of proteins. The aim of the present study was to understand the differences in the mode of dissociation between the E. coli and P. vulgaris Trpases. In particular, the effect of mutations along the molecular axes of homotetrameric Trpase on its dissociation was studied. To answer this question, two groups of mutants of the E. coli enzyme were created to resemble the amino-acid sequence of P. vulgaris Trpase. In one group, residues 15 and 59 that are located along the molecular axis R (also termed the noncatalytic axis) were mutated. The second group included a mutation at position 298, located along the molecular axis Q (also termed the catalytic axis). Replacing amino-acid residues along the R axis resulted in dissociation of the tetramers into monomers, similar to the P. vulgaris Trpase, while replacing amino-acid residues along the Q axis resulted in dissociation into dimers only. The crystal structure of the V59M mutant of E. coli Trpase was also determined in its apo form and was found to be similar to that of the wild type. This study suggests that in E. coli Trpase hydrophobic interactions along the R axis hold the two monomers together more strongly, preventing the dissociation of the dimers into monomers. Mutation of position 298 along the Q axis to a charged residue resulted in tetramers that are less susceptible to dissociation. Thus, the results indicate that dissociation of E. coli Trpase into dimers occurs along the molecular Q axis.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Escherichia coli/química
Subunidades Proteicas/química
Proteus vulgaris/química
Triptofano/química
Triptofanase/química
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Sítios de Ligação
Biocatálise
Cristalografia por Raios X
Escherichia coli/enzimologia
Escherichia coli/genética
Expressão Gênica
Cinética
Modelos Moleculares
Mutação
Ligação Proteica
Multimerização Proteica
Estrutura Secundária de Proteína
Estrutura Terciária de Proteína
Subunidades Proteicas/genética
Subunidades Proteicas/metabolismo
Proteus vulgaris/enzimologia
Proteus vulgaris/genética
Fosfato de Piridoxal/química
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Especificidade da Espécie
Homologia Estrutural de Proteína
Triptofano/metabolismo
Triptofanase/genética
Triptofanase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Protein Subunits); 0 (Recombinant Proteins); 5V5IOJ8338 (Pyridoxal Phosphate); 8DUH1N11BX (Tryptophan); EC 4.1.99.1 (Tryptophanase)
[Em] Mês de entrada:1609
[Cu] Atualização por classe:151202
[Lr] Data última revisão:
151202
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151203
[St] Status:MEDLINE
[do] DOI:10.1107/S139900471501799X


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[PMID]:26527264
[Au] Autor:Rety S; Deschamps P; Leulliot N
[Ad] Endereço:Laboratoire de Cristallographie et RMN Biologiques, UMR CNRS 8015, Université Paris Descartes, Sorbonne Paris Cité, Faculté de Pharmacie de Paris, Paris, France.
[Ti] Título:Structure of Escherichia coli tryptophanase purified from an alkaline-stressed bacterial culture.
[So] Source:Acta Crystallogr F Struct Biol Commun;71(Pt 11):1378-83, 2015 Nov.
[Is] ISSN:2053-230X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Tryptophanase is a bacterial enzyme involved in the degradation of tryptophan to indole, pyruvate and ammonia, which are compounds that are essential for bacterial survival. Tryptophanase is often overexpressed in stressed cultures. Large amounts of endogenous tryptophanase were purified from Escherichia coli BL21 strain overexpressing another recombinant protein. Tryptophanase was crystallized in space group P6522 in the apo form without pyridoxal 5'-phosphate bound in the active site.
[Mh] Termos MeSH primário: Antiácidos/farmacologia
Proteínas de Escherichia coli/química
Escherichia coli/enzimologia
Triptofanase/química
[Mh] Termos MeSH secundário: Técnicas de Cultura de Células
Cristalização
Escherichia coli/efeitos dos fármacos
Proteínas de Escherichia coli/isolamento & purificação
Seres Humanos
Estrutura Secundária de Proteína
Estrutura Terciária de Proteína
Triptofanase/isolamento & purificação
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Antacids); 0 (Escherichia coli Proteins); EC 4.1.99.1 (Tryptophanase)
[Em] Mês de entrada:1609
[Cu] Atualização por classe:171101
[Lr] Data última revisão:
171101
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151104
[St] Status:MEDLINE
[do] DOI:10.1107/S2053230X15017549



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