Base de dados : MEDLINE
Pesquisa : D08.811.913.050.600 [Categoria DeCS]
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  1 / 28 MEDLINE  
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[PMID]:28493869
[Au] Autor:Douglas SM; Chubiz LM; Harcombe WR; Marx CJ
[Ad] Endereço:Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts, United States of America.
[Ti] Título:Identification of the potentiating mutations and synergistic epistasis that enabled the evolution of inter-species cooperation.
[So] Source:PLoS One;12(5):e0174345, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Microbes often engage in cooperation through releasing biosynthetic compounds required by other species to grow. Given that production of costly biosynthetic metabolites is generally subjected to multiple layers of negative feedback, single mutations may frequently be insufficient to generate cooperative phenotypes. Synergistic epistatic interactions between multiple coordinated changes may thus often underlie the evolution of cooperation through overproduction of metabolites. To test the importance of synergistic mutations in cooperation we used an engineered bacterial consortium of an Escherichia coli methionine auxotroph and Salmonella enterica. S. enterica relies on carbon by-products from E. coli if lactose is the only carbon source. Directly selecting wild-type S. enterica in an environment that favored cooperation through secretion of methionine only once led to a methionine producer, and this producer both took a long time to emerge and was not very effective at cooperating. On the other hand, when an initial selection for resistance of S. enterica to a toxic methionine analog, ethionine, was used, subsequent selection for cooperation with E. coli was rapid, and the resulting double mutants were much more effective at cooperation. We found that potentiating mutations in metJ increase expression of metA, which encodes the first step of methionine biosynthesis. This increase in expression is required for the previously identified actualizing mutations in metA to generate cooperation. This work highlights that where biosynthesis of metabolites involves multiple layers of regulation, significant secretion of those metabolites may require multiple mutations, thereby constraining the evolution of cooperation.
[Mh] Termos MeSH primário: Apoproteínas/genética
Epistasia Genética
Proteínas de Escherichia coli/genética
Escherichia coli/genética
Homoserina O-Succiniltransferase/genética
Proteínas Repressoras/genética
[Mh] Termos MeSH secundário: Vias Biossintéticas
Escherichia coli/metabolismo
Evolução Molecular
Regulação Bacteriana da Expressão Gênica
Metionina/biossíntese
Mutação
Salmonella enterica/genética
Salmonella enterica/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Apoproteins); 0 (Escherichia coli Proteins); 0 (MetJ protein, E coli); 0 (Repressor Proteins); AE28F7PNPL (Methionine); EC 2.3.1.46 (Homoserine O-Succinyltransferase); EC 2.3.1.46 (metA protein, E coli)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170911
[Lr] Data última revisão:
170911
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170512
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0174345


  2 / 28 MEDLINE  
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[PMID]:25329174
[Au] Autor:Mordukhova EA; Pan JG
[Ad] Endereço:Superbacteria Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea.
[Ti] Título:Stabilization of homoserine-O-succinyltransferase (MetA) decreases the frequency of persisters in Escherichia coli under stressful conditions.
[So] Source:PLoS One;9(10):e110504, 2014.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacterial persisters are a small subpopulation of cells that exhibit multi-drug tolerance without genetic changes. Generally, persistence is associated with a dormant state in which the microbial cells are metabolically inactive. The bacterial response to unfavorable environmental conditions (heat, oxidative, acidic stress) induces the accumulation of aggregated proteins and enhances formation of persister cells in Escherichia coli cultures. We have found that methionine supplementation reduced the frequency of persisters at mild (37°C) and elevated (42°C) temperatures, as well as in the presence of acetate. Homoserine-o-succinyltransferase (MetA), the first enzyme in the methionine biosynthetic pathway, is prone to aggregation under many stress conditions, resulting in a methionine limitation in E. coli growth. Overexpression of MetA induced the greatest number of persisters at 42°C, which is correlated to an increased level of aggregated MetA. Substitution of the native metA gene on the E. coli K-12 WE chromosome by a mutant gene encoding the stabilized MetA led to reduction in persisters at the elevated temperature and in the presence of acetate, as well as lower aggregation of the mutated MetA. Decreased persister formation at 42°C was confirmed also in E. coli K-12 W3110 and a fast-growing WErph+ mutant harboring the stabilized MetA. Thus, this is the first study to demonstrate manipulation of persister frequency under stressful conditions by stabilization of a single aggregation-prone protein, MetA.
[Mh] Termos MeSH primário: Proteínas de Escherichia coli/metabolismo
Escherichia coli/genética
Homoserina O-Succiniltransferase/metabolismo
Estresse Fisiológico/genética
[Mh] Termos MeSH secundário: Resistência a Múltiplos Medicamentos/genética
Escherichia coli/fisiologia
Proteínas de Escherichia coli/genética
Homosserina/genética
Homosserina/metabolismo
Homoserina O-Succiniltransferase/genética
Metionina/genética
Metionina/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Escherichia coli Proteins); 6KA95X0IVO (Homoserine); AE28F7PNPL (Methionine); EC 2.3.1.46 (Homoserine O-Succinyltransferase); EC 2.3.1.46 (metA protein, E coli)
[Em] Mês de entrada:1512
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141021
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0110504


  3 / 28 MEDLINE  
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[PMID]:23898868
[Au] Autor:Mordukhova EA; Kim D; Pan JG
[Ad] Endereço:Superbacteria Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Yuseong-gu, Daejeon 305-806, South Korea.
[Ti] Título:Stabilized homoserine o-succinyltransferases (MetA) or L-methionine partially recovers the growth defect in Escherichia coli lacking ATP-dependent proteases or the DnaK chaperone.
[So] Source:BMC Microbiol;13:179, 2013 Jul 30.
[Is] ISSN:1471-2180
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The growth of Escherichia coli at elevated temperatures is limited due to the inherent instability of homoserine o-succinyltransferase, MetA, which is the first enzyme in the methionine biosynthesis pathway. MetA is also unstable under other stressful conditions, such as weak organic acids and oxidative stress. The MetA protein unfolds, even at 25°C, forms considerable aggregates at 37°C and completely aggregates at 44°C. RESULTS: We extended the MetA mutation studies using a consensus concept based on statistics and sequence database analysis to predict the point mutations resulting in increased MetA stability. In this study, four single amino acid substitutions (Q96K, I124L, I229Y and F247Y) in MetA designed according to the consensus concept and using the I-mutant2.0 modeling tool conferred accelerated growth on the E. coli strain WE at 44°C. MetA mutants that enabled E. coli growth at higher temperatures did not display increased melting temperatures (Tm) or enhanced catalytic activity but did show improved in vivo stability at mild (37°C) and elevated (44°C) temperatures. Notably, we observed that the stabilized MetA mutants partially recovered the growth defects of E. coli mutants in which ATP-dependent proteases or the DnaK chaperone was deleted. These results suggest that the impaired growth of these E. coli mutants primarily reflect the inherent instability of MetA and, thus, the methionine supply. As further evidence, the addition of methionine recovered most of the growth defects in mutants lacking either ATP-dependent proteases or the DnaK chaperone. CONCLUSIONS: A collection of stable single-residue mutated MetA enzymes were constructed and investigated as background for engineering the stabilized mutants. In summary, the mutations in a single gene, metA, reframe the window of growth temperature in both normal and mutant E. coli strains.
[Mh] Termos MeSH primário: Proteases Dependentes de ATP/deficiência
Proteínas de Escherichia coli/metabolismo
Escherichia coli/crescimento & desenvolvimento
Proteínas de Choque Térmico HSP70/deficiência
Homoserina O-Succiniltransferase/metabolismo
Metionina/metabolismo
[Mh] Termos MeSH secundário: Substituição de Aminoácidos
Estabilidade Enzimática
Escherichia coli/enzimologia
Escherichia coli/genética
Escherichia coli/efeitos da radiação
Proteínas de Escherichia coli/química
Proteínas de Escherichia coli/genética
Homoserina O-Succiniltransferase/química
Homoserina O-Succiniltransferase/genética
Mutação de Sentido Incorreto
Mutação Puntual
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Escherichia coli Proteins); 0 (HSP70 Heat-Shock Proteins); AE28F7PNPL (Methionine); EC 2.3.1.46 (Homoserine O-Succinyltransferase); EC 2.3.1.46 (metA protein, E coli); EC 3.4.21.- (ATP-Dependent Proteases); EC 3.6.1.- (dnaK protein, E coli)
[Em] Mês de entrada:1310
[Cu] Atualização por classe:150423
[Lr] Data última revisão:
150423
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130801
[St] Status:MEDLINE
[do] DOI:10.1186/1471-2180-13-179


  4 / 28 MEDLINE  
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[PMID]:23085540
[Au] Autor:Rotem O; Biran D; Ron EZ
[Ad] Endereço:Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv 69978, Israel. orotem82@walla.co.il
[Ti] Título:Methionine biosynthesis in Agrobacterium tumefaciens: study of the first enzyme.
[So] Source:Res Microbiol;164(1):12-6, 2013 Jan.
[Is] ISSN:1769-7123
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:Here we characterize the first step in methionine biosynthesis in Agrobacterium tumefaciens, an α-proteobacterium. We explored the metA gene and its products and found several unique properties. Although the gene was annotated as a homoserine transsuccinylase, based upon sequence similarity to characterized homologs in other bacteria, including Escherichia coli, the enzyme uses acetyl-CoA as a substrate and therefore is functionally a transacetylase. Moreover, the protein is thermolabile and the gene is under regulation of heat shock transcriptional activator σ32. 3. The gene has a SAM-riboswitch, which shuts off transcription by σ-32 as well as by the vegetative σ-70.
[Mh] Termos MeSH primário: Agrobacterium tumefaciens/enzimologia
Metionina/biossíntese
[Mh] Termos MeSH secundário: Agrobacterium tumefaciens/genética
Sequência de Aminoácidos
Estabilidade Enzimática
Regulação Bacteriana da Expressão Gênica
Proteínas de Choque Térmico/genética
Proteínas de Choque Térmico/metabolismo
Homoserina O-Succiniltransferase/química
Homoserina O-Succiniltransferase/genética
Homoserina O-Succiniltransferase/metabolismo
Dados de Sequência Molecular
Riboswitch
Alinhamento de Sequência
Temperatura Ambiente
Transcrição Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Heat-Shock Proteins); 0 (Riboswitch); AE28F7PNPL (Methionine); EC 2.3.1.46 (Homoserine O-Succinyltransferase)
[Em] Mês de entrada:1306
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:121023
[St] Status:MEDLINE


  5 / 28 MEDLINE  
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[PMID]:19596340
[Au] Autor:Rokney A; Shagan M; Kessel M; Smith Y; Rosenshine I; Oppenheim AB
[Ad] Endereço:Department of Microbiology and Molecular Genetics, IMRIC, The Hebrew University, Jerusalem, Israel. assaf.rokney@mail.huji.ac.il
[Ti] Título:E. coli transports aggregated proteins to the poles by a specific and energy-dependent process.
[So] Source:J Mol Biol;392(3):589-601, 2009 Sep 25.
[Is] ISSN:1089-8638
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Aggregation of proteins due to failure of quality control mechanisms is deleterious to both eukaryotes and prokaryotes. We found that in Escherichia coli, protein aggregates are delivered to the pole and form a large polar aggregate (LPA). The formation of LPAs involves two steps: the formation of multiple small aggregates and the delivery of these aggregates to the pole to form an LPA. Formation of randomly distributed aggregates, their delivery to the poles, and LPA formation are all energy-dependent processes. The latter steps require the proton motive force, activities of the DnaK and DnaJ chaperones, and MreB. About 90 min after their formation, the LPAs are dissolved in a process that is dependent upon ClpB, DnaK, and energy. Our results confirm and substantiate the notion that the formation of LPAs allows asymmetric inheritance of the aggregated proteins to a small number of daughter cells, enabling their rapid elimination from most of the bacterial population. Moreover, the results show that the processing of aggregated proteins by the protein quality control system is a multi-step process with distinct spatial and temporal controls.
[Mh] Termos MeSH primário: Trifosfato de Adenosina/metabolismo
Metabolismo Energético
Proteínas de Escherichia coli/metabolismo
Escherichia coli
Corpos de Inclusão/metabolismo
Chaperonas Moleculares/metabolismo
[Mh] Termos MeSH secundário: Animais
Polaridade Celular
Endopeptidase Clp
Escherichia coli/citologia
Escherichia coli/metabolismo
Proteínas de Escherichia coli/genética
Proteínas de Choque Térmico HSP40/genética
Proteínas de Choque Térmico HSP40/metabolismo
Proteínas de Choque Térmico HSP70/genética
Proteínas de Choque Térmico HSP70/metabolismo
Proteínas de Choque Térmico/genética
Proteínas de Choque Térmico/metabolismo
Homoserina O-Succiniltransferase/genética
Homoserina O-Succiniltransferase/metabolismo
Chaperonas Moleculares/genética
Proteínas Recombinantes de Fusão/genética
Proteínas Recombinantes de Fusão/metabolismo
Proteínas Repressoras/genética
Proteínas Repressoras/metabolismo
Proteínas Virais Reguladoras e Acessórias/genética
Proteínas Virais Reguladoras e Acessórias/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 (DnaJ protein, E coli); 0 (Escherichia coli Proteins); 0 (HSP40 Heat-Shock Proteins); 0 (HSP70 Heat-Shock Proteins); 0 (Heat-Shock Proteins); 0 (Molecular Chaperones); 0 (Recombinant Fusion Proteins); 0 (Repressor Proteins); 0 (Viral Regulatory and Accessory Proteins); 0 (phage repressor proteins); 8L70Q75FXE (Adenosine Triphosphate); EC 2.3.1.46 (Homoserine O-Succinyltransferase); EC 2.3.1.46 (metA protein, E coli); EC 3.4.21.92 (Endopeptidase Clp); EC 3.6.1.- (dnaK protein, E coli); EC 3.6.1.3 (ClpB protein, E coli)
[Em] Mês de entrada:0911
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:090715
[St] Status:MEDLINE
[do] DOI:10.1016/j.jmb.2009.07.009


  6 / 28 MEDLINE  
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[PMID]:18978085
[Au] Autor:Mordukhova EA; Lee HS; Pan JG
[Ad] Endereço:Systems Microbiology Research Center, Korea Research Institute of Bioscience and Biotechnology, 52 Eoun-dong, Yuseong-gu, Daejeon 305-340, Korea.
[Ti] Título:Improved thermostability and acetic acid tolerance of Escherichia coli via directed evolution of homoserine o-succinyltransferase.
[So] Source:Appl Environ Microbiol;74(24):7660-8, 2008 Dec.
[Is] ISSN:1098-5336
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In Escherichia coli, growth is limited at elevated temperatures mainly because of the instability of a single enzyme, homoserine o-succinyltransferase (MetA), the first enzyme in the methionine biosynthesis pathway. The metA gene from the thermophile Geobacillus kaustophilus cloned into the E. coli chromosome was found to enhance the growth of the host strain at elevated temperature (44 degrees C), thus confirming the limited growth of E. coli due to MetA instability. In order to improve E. coli growth at higher temperatures, we used random mutagenesis to obtain a thermostable MetA(E. coli) protein. Sequencing of the thermotolerant mutant showed five amino acid substitutions: S61T, E213V, I229T, N267D, and N271K. An E. coli strain with the mutated metA gene chromosomally inserted showed accelerated growth over a temperature range of 34 to 44 degrees C. We used the site-directed metA mutants to identify two amino acid residues responsible for the sensitivity of MetA(E. coli) to both heat and acids. Replacement of isoleucine 229 with threonine and asparagine 267 with aspartic acid stabilized the protein. The thermostable MetA(E. coli) enzymes showed less aggregation in vivo at higher temperature, as well as upon acetic acid treatment. The data presented here are the first to show improved E. coli growth at higher temperatures solely due to MetA stabilization and provide new knowledge for designing E. coli strains that grow at higher temperatures, thus reducing the cooling cost of bioprocesses.
[Mh] Termos MeSH primário: Ácido Acético/farmacologia
Antibacterianos/farmacologia
Tolerância a Medicamentos
Proteínas de Escherichia coli/genética
Proteínas de Escherichia coli/metabolismo
Escherichia coli/enzimologia
Escherichia coli/fisiologia
Resposta ao Choque Térmico
Homoserina O-Succiniltransferase/genética
Homoserina O-Succiniltransferase/metabolismo
[Mh] Termos MeSH secundário: Substituição de Aminoácidos/genética
Bacillaceae/enzimologia
Bacillaceae/genética
Vias Biossintéticas
Análise Mutacional de DNA
DNA Bacteriano/genética
Escherichia coli/genética
Escherichia coli/crescimento & desenvolvimento
Mutagênese
Mutagênese Sítio-Dirigida
Mutação de Sentido Incorreto
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (DNA, Bacterial); 0 (Escherichia coli Proteins); EC 2.3.1.46 (Homoserine O-Succinyltransferase); EC 2.3.1.46 (metA protein, E coli); Q40Q9N063P (Acetic Acid)
[Em] Mês de entrada:0901
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:081104
[St] Status:MEDLINE
[do] DOI:10.1128/AEM.00654-08


  7 / 28 MEDLINE  
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[PMID]:18216013
[Au] Autor:Zubieta C; Arkus KA; Cahoon RE; Jez JM
[Ad] Endereço:Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA.
[Ti] Título:A single amino acid change is responsible for evolution of acyltransferase specificity in bacterial methionine biosynthesis.
[So] Source:J Biol Chem;283(12):7561-7, 2008 Mar 21.
[Is] ISSN:0021-9258
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacteria and yeast rely on either homoserine transsuccinylase (HTS, metA) or homoserine transacetylase (HTA; met2) for the biosynthesis of methionine. Although HTS and HTA catalyze similar chemical reactions, these proteins are typically unrelated in both sequence and three-dimensional structure. Here we present the 2.0 A resolution x-ray crystal structure of the Bacillus cereus metA protein in complex with homoserine, which provides the first view of a ligand bound to either HTA or HTS. Surprisingly, functional analysis of the B. cereus metA protein shows that it does not use succinyl-CoA as a substrate. Instead, the protein catalyzes the transacetylation of homoserine using acetyl-CoA. Therefore, the B. cereus metA protein functions as an HTA despite greater than 50% sequence identity with bona fide HTS proteins. This result emphasizes the need for functional confirmation of annotations of enzyme function based on either sequence or structural comparisons. Kinetic analysis of site-directed mutants reveals that the B. cereus metA protein and the E. coli HTS share a common catalytic mechanism. Structural and functional examination of the B. cereus metA protein reveals that a single amino acid in the active site determines acetyl-CoA (Glu-111) versus succinyl-CoA (Gly-111) specificity in the metA-like of acyltransferases. Switching of this residue provides a mechanism for evolving substrate specificity in bacterial methionine biosynthesis. Within this enzyme family, HTS and HTA activity likely arises from divergent evolution in a common structural scaffold with conserved catalytic machinery and homoserine binding sites.
[Mh] Termos MeSH primário: Substituição de Aminoácidos
Bacillus cereus/enzimologia
Proteínas de Bactérias/química
Evolução Molecular
Homoserina O-Succiniltransferase/química
[Mh] Termos MeSH secundário: Acetilcoenzima A/química
Acetilcoenzima A/genética
Acetilcoenzima A/metabolismo
Acetiltransferases/química
Acetiltransferases/genética
Acil Coenzima A/química
Acil Coenzima A/genética
Acil Coenzima A/metabolismo
Bacillus cereus/genética
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Cristalografia por Raios X
Escherichia coli/enzimologia
Escherichia coli/genética
Homoserina O-Succiniltransferase/genética
Homoserina O-Succiniltransferase/metabolismo
Metionina/biossíntese
Metionina/química
Metionina/genética
Estrutura Terciária de Proteína/fisiologia
Especificidade por Substrato/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Acyl Coenzyme A); 0 (Bacterial Proteins); 604-98-8 (succinyl-coenzyme A); 72-89-9 (Acetyl Coenzyme A); AE28F7PNPL (Methionine); EC 2.3.1.- (Acetyltransferases); EC 2.3.1.31 (homoserine O-acetyltransferase); EC 2.3.1.46 (Homoserine O-Succinyltransferase)
[Em] Mês de entrada:0805
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:080125
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M709283200


  8 / 28 MEDLINE  
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[PMID]:17662245
[Au] Autor:Ziegler K; Yusupov M; Bishop B; Born TL
[Ad] Endereço:Department of Chemistry and Biochemistry, George Mason University, 10900 University Blvd, Manassas, VA 20110, USA.
[Ti] Título:Substrate analysis of homoserine acyltransferase from Bacillus cereus.
[So] Source:Biochem Biophys Res Commun;361(2):510-5, 2007 Sep 21.
[Is] ISSN:0006-291X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Substrate specificity within the family of enzymes designated as homoserine transsuccinylases is variable, with some organisms utilizing succinyl-CoA and other organisms utilizing acetyl-CoA. In this study it is shown that the enzyme from Bacillus cereus uses acetyl-CoA as its acyl donor, but its catalytic rate is significantly lower than other HTS family members. BcHTS is inactivated by both iodoacetamide and diethyl pyrocarbonate and the enzyme can be partially protected from inactivation by the presence of succinyl-CoA. This leads to the conclusion that BcHTS can bind both acetyl-CoA and succinyl-CoA and suggests that it may represent an intermediate between the succinate-transferring HTS family members and the acetate-transferring HTS family members. The B. cereus enzyme was unable to rescue growth of an Escherichia coli strain lacking a functional transsuccinylase, however.
[Mh] Termos MeSH primário: Bacillus cereus/enzimologia
Homoserina O-Succiniltransferase/metabolismo
[Mh] Termos MeSH secundário: Clonagem Molecular
Dietil Pirocarbonato/farmacologia
Ativação Enzimática/efeitos dos fármacos
Homosserina/química
Homosserina/metabolismo
Homoserina O-Succiniltransferase/isolamento & purificação
Concentração de Íons de Hidrogênio
Iodoacetamida/farmacologia
Cinética
Metionina/metabolismo
Proteínas Mutantes/metabolismo
Nitrofenóis/farmacologia
Especificidade por Substrato/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Mutant Proteins); 0 (Nitrophenols); 6KA95X0IVO (Homoserine); 830-03-5 (4-nitrophenyl acetate); AE28F7PNPL (Methionine); EC 2.3.1.46 (Homoserine O-Succinyltransferase); LMR3LZG146 (Diethyl Pyrocarbonate); ZRH8M27S79 (Iodoacetamide)
[Em] Mês de entrada:0709
[Cu] Atualização por classe:161122
[Lr] Data última revisão:
161122
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:070731
[St] Status:MEDLINE


  9 / 28 MEDLINE  
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[PMID]:17546672
[Au] Autor:Zubieta C; Krishna SS; McMullan D; Miller MD; Abdubek P; Agarwalla S; Ambing E; Astakhova T; Axelrod HL; Carlton D; Chiu HJ; Clayton T; Deller M; DiDonato M; Duan L; Elsliger MA; Grzechnik SK; Hale J; Hampton E; Han GW; Haugen J; Jaroszewski L; Jin KK; Klock HE; Knuth MW; Koesema E; Kumar A; Marciano D; Morse AT; Nigoghossian E; Oommachen S; Reyes R; Rife CL; van den Bedem H; Weekes D; White A; Xu Q; Hodgson KO; Wooley J; Deacon AM; Godzik A; Lesley SA; Wilson IA
[Ad] Endereço:Joint Center for Structural Genomics, Stanford University, Menlo Park, California, USA.
[Ti] Título:Crystal structure of homoserine O-succinyltransferase from Bacillus cereus at 2.4 A resolution.
[So] Source:Proteins;68(4):999-1005, 2007 Sep 01.
[Is] ISSN:1097-0134
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Bacillus cereus/enzimologia
Homoserina O-Succiniltransferase/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Bactérias/química
Cristalografia por Raios X
Dimerização
Haemophilus influenzae/enzimologia
Modelos Moleculares
Dados de Sequência Molecular
Conformação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Bacterial Proteins); EC 2.3.1.46 (Homoserine O-Succinyltransferase)
[Em] Mês de entrada:0710
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:070605
[St] Status:MEDLINE


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Fotocópia
[PMID]:17490766
[Au] Autor:Mizrahi I; Biran D; Gur E; Ron EZ
[Ad] Endereço:Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv, 69978 Israel.
[Ti] Título:Tools for the study of protein quality control systems: use of truncated homoserine trans-succinylase as a model substrate for ATP-dependent proteolysis in Escherichia coli.
[So] Source:J Microbiol Methods;70(1):82-5, 2007 Jul.
[Is] ISSN:0167-7012
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Protein quality control, mediated by chaperones and ATP-dependent proteases, is essential for maintaining balanced growth and for regulating critical processes. To study these systems it is necessary to have model substrate proteins. However, most cellular proteins are stable and the few unstable proteins are usually regulatory and present in low concentrations, making them unsuitable for studies, especially in vivo. We present HTS(Delta1-6), a truncated homoserine trans-succinylase (HTS) which is unstable, can be expressed at high levels and has an enzymatic, measurable, activity. This protein can serve as a good model substrate for Escherichia coli ATP-dependent proteolysis.
[Mh] Termos MeSH primário: Proteases Dependentes de ATP/metabolismo
Proteínas de Bactérias/metabolismo
Proteínas de Escherichia coli/metabolismo
Escherichia coli/metabolismo
Homoserina O-Succiniltransferase/metabolismo
Biologia Molecular/métodos
[Mh] Termos MeSH secundário: Escherichia coli/genética
Proteínas de Escherichia coli/genética
Resposta ao Choque Térmico
Homoserina O-Succiniltransferase/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Escherichia coli Proteins); EC 2.3.1.46 (Homoserine O-Succinyltransferase); EC 2.3.1.46 (metA protein, E coli); EC 3.4.21.- (ATP-Dependent Proteases)
[Em] Mês de entrada:0708
[Cu] Atualização por classe:070626
[Lr] Data última revisão:
070626
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:070511
[St] Status:MEDLINE



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