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Pesquisa : D08.811.913.696.630.025 [Categoria DeCS]
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[PMID]:28654654
[Au] Autor:Post DMB; Schilling B; Reinders LM; D'Souza AK; Ketterer MR; Kiel SJ; Chande AT; Apicella MA; Gibson BW
[Ad] Endereço:Buck Institute for Research on Aging, Novato, California, United States of America.
[Ti] Título:Identification and characterization of AckA-dependent protein acetylation in Neisseria gonorrhoeae.
[So] Source:PLoS One;12(6):e0179621, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Neisseria gonorrhoeae, the causative agent of gonorrhea, has a number of factors known to contribute to pathogenesis; however, a full understanding of these processes and their regulation has proven to be elusive. Post-translational modifications (PTMs) of bacterial proteins are now recognized as one mechanism of protein regulation. In the present study, Western blot analyses, with an anti-acetyl-lysine antibody, indicated that a large number of gonococcal proteins are post-translationally modified. Previous work has shown that Nε-lysine acetylation can occur non-enzymatically with acetyl-phosphate (AcP) as the acetyl donor. In the current study, an acetate kinase mutant (1291ackA), which accumulates AcP, was generated in N. gonorrhoeae. Broth cultures of N. gonorrhoeae 1291wt and 1291ackA were grown, proteins extracted and digested, and peptides containing acetylated-lysines (K-acetyl) were affinity-enriched from both strains. Mass spectrometric analyses of these samples identified a total of 2686 unique acetylation sites. Label-free relative quantitation of the K-acetyl peptides derived from the ackA and wild-type (wt) strains demonstrated that 109 acetylation sites had an ackA/wt ratio>2 and p-values <0.05 in at least 2/3 of the biological replicates and were designated as "AckA-dependent". Regulated K-acetyl sites were found in ribosomal proteins, central metabolism proteins, iron acquisition and regulation proteins, pilus assembly and regulation proteins, and a two-component response regulator. Since AckA is part of a metabolic pathway, comparative growth studies of the ackA mutant and wt strains were performed. The mutant showed a growth defect under aerobic conditions, an inability to grow anaerobically, and a defect in biofilm maturation. In conclusion, the current study identified AckA-dependent acetylation sites in N. gonorrhoeae and determined that these sites are found in a diverse group of proteins. This work lays the foundation for future studies focusing on specific acetylation sites that may have relevance in gonococcal pathogenesis and metabolism.
[Mh] Termos MeSH primário: Acetato Quinase/metabolismo
Proteínas de Bactérias/metabolismo
Redes e Vias Metabólicas/fisiologia
Neisseria gonorrhoeae/metabolismo
[Mh] Termos MeSH secundário: Acetato Quinase/genética
Acetilação
Proteínas de Bactérias/genética
Regulação Bacteriana da Expressão Gênica
Espectrometria de Massas
Fosforilação
Processamento de Proteína Pós-Traducional
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); EC 2.7.2.1 (Acetate Kinase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170628
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0179621


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[PMID]:28130304
[Au] Autor:Kim JN; Burne RA
[Ad] Endereço:Department of Microbiology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea.
[Ti] Título:CcpA and CodY Coordinate Acetate Metabolism in Streptococcus mutans.
[So] Source:Appl Environ Microbiol;83(7), 2017 Apr 01.
[Is] ISSN:1098-5336
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In the dental caries pathogen , phosphotransacetylase (Pta) and acetate kinase (Ack) convert pyruvate into acetate with the concomitant generation of ATP. The genes for this pathway are tightly regulated by multiple environmental and intracellular inputs, but the basis for differential expression of the genes for Pta and Ack in had not been investigated. Here, we show that inactivation in of or reduced the activity of the promoter, whereas a mutant displayed elevated promoter activity. The interactions of CcpA with the promoter regions of both genes were observed using electrophoretic mobility shift and DNase protection assays. CodY bound to the promoter region but only in the presence of branched-chain amino acids (BCAAs). DNase footprinting revealed that the upstream region of both genes contains two catabolite-responsive elements ( and ) that can be bound by CcpA. Notably, the site of overlaps with a CodY-binding site. The CcpA- and CodY-binding sites in the promoter region of both genes were further defined by site-directed mutagenesis. Some differences between the reported consensus CodY binding site and the region protected by CodY were noted. Transcription of the and genes in the mutant strain was markedly different at low pH relative to transcription at neutral pH. Thus, CcpA and CodY are direct regulators of transcription of and in that optimize acetate metabolism in response to carbohydrate, amino acid availability, and environmental pH. The human dental caries pathogen is remarkably adept at coping with extended periods of carbohydrate limitation during fasting periods. The phosphotransacetylase-acetate kinase (Pta-Ack) pathway in modulates carbohydrate flux and fine-tunes the ability of the organisms to cope with stressors that are commonly encountered in the oral cavity. Here, we show that CcpA controls transcription of the and genes via direct interaction with the promoter regions of both genes and that branched-chain amino acids (BCAAs), particularly isoleucine, enhance the ability of CodY to bind to the promoter region of the gene. A working model is proposed to explain how regulation of and genes by these allosterically controlled regulatory proteins facilitates proper carbon flow and energy production, which are essential functions during infection and pathogenesis as carbohydrate and amino acid availability continually fluctuate.
[Mh] Termos MeSH primário: Acetatos/metabolismo
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Regulação Bacteriana da Expressão Gênica
Streptococcus mutans/genética
Streptococcus mutans/metabolismo
[Mh] Termos MeSH secundário: Acetato Quinase/genética
Aminoácidos de Cadeia Ramificada/metabolismo
Sítios de Ligação
Metabolismo dos Carboidratos
Proteínas de Ligação a DNA/genética
Proteínas de Ligação a DNA/metabolismo
Cárie Dentária/microbiologia
Concentração de Íons de Hidrogênio
Mutagênese Sítio-Dirigida
Fosfato Acetiltransferase/genética
Fosfato Acetiltransferase/metabolismo
Regiões Promotoras Genéticas
Ácido Pirúvico/metabolismo
Transcrição Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetates); 0 (Amino Acids, Branched-Chain); 0 (Bacterial Proteins); 0 (DNA-Binding Proteins); 8558G7RUTR (Pyruvic Acid); EC 2.3.1.8 (Phosphate Acetyltransferase); EC 2.7.2.1 (Acetate Kinase)
[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:170129
[St] Status:MEDLINE


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[PMID]:27380420
[Au] Autor:Jiang Y; Tao R; Shen Z; Sun L; Zhu F; Yang S
[Ad] Endereço:Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
[Ti] Título:Enzymatic Production of Glutathione by Bifunctional γ-Glutamylcysteine Synthetase/Glutathione Synthetase Coupled with In Vitro Acetate Kinase-Based ATP Generation.
[So] Source:Appl Biochem Biotechnol;180(7):1446-1455, 2016 Dec.
[Is] ISSN:1559-0291
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Glutathione (γ-glutamyl-L-cysteinylglycine, GSH) is a pharmaceutical compound often used in food additives and the cosmetics industry. GSH can be produced biologically from L-glutamic acid, L-cysteine, and glycine through an enzymatic process traditionally involving two sequential adenosine triphosphate (ATP)-dependent reactions catalyzed by γ-glutamylcysteine synthetase (γ-GCS or GSHI, EC 6.3.2.2) and GSH synthetase (GS or GSHII, EC 6.3.2.3). Here, we report the enzymatic production of GSH by recombinant cell-free bifunctional γ-glutamylcysteine synthetase/glutathione synthetase (γ-GCS-GS or GshF) coupled with in vitro acetate kinase-based ATP generation. GSH production by an acetate kinase-integrated Escherichia coli Rosetta(DE3) mutant expressing Streptococcus thermophilus GshF reached 18.3 ± 0.1 g l (59.5 ± 0.3 mM) within 3 h, with a molar yield of 0.75 ± 0.00 mol mol added cysteine and a productivity of 6.1 ± 0.0 g l h . This is the highest GSH titer reported to date. This newly developed biocatalytic process offers a promising approach for meeting the industrial requirements for GSH production.
[Mh] Termos MeSH primário: Acetato Quinase/metabolismo
Trifosfato de Adenosina/biossíntese
Biotecnologia/métodos
Dipeptídeos/metabolismo
Glutamato-Cisteína Ligase/metabolismo
Glutationa Sintase/metabolismo
Glutationa/biossíntese
[Mh] Termos MeSH secundário: Escherichia coli/metabolismo
Mutação/genética
Streptococcus/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Dipeptides); 8L70Q75FXE (Adenosine Triphosphate); EC 2.7.2.1 (Acetate Kinase); EC 6.3.2.2 (Glutamate-Cysteine Ligase); EC 6.3.2.3 (Glutathione Synthase); GAN16C9B8O (Glutathione); M984VJS48P (gamma-glutamylcysteine)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170124
[Lr] Data última revisão:
170124
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160706
[St] Status:MEDLINE


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[PMID]:27348810
[Au] Autor:Liu L; Duan X; Wu J
[Ad] Endereço:State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.
[Ti] Título:L-Tryptophan Production in Escherichia coli Improved by Weakening the Pta-AckA Pathway.
[So] Source:PLoS One;11(6):e0158200, 2016.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Acetate accumulation during the fermentation process of Escherichia coli FB-04, an L-tryptophan production strain, is detrimental to L-tryptophan production. In an initial attempt to reduce acetate formation, the phosphate acetyltransferase gene (pta) from E. coli FB-04 was deleted, forming strain FB-04(Δpta). Unfortunately, FB-04(Δpta) exhibited a growth defect. Therefore, pta was replaced with a pta variant (pta1) from E. coli CCTCC M 2016009, forming strain FB-04(pta1). Pta1 exhibits lower catalytic capacity and substrate affinity than Pta because of a single amino acid substitution (Pro69Leu). FB-04(pta1) lacked the growth defect of FB-04(Δpta) and showed improved fermentation performance. Strain FB-04(pta1) showed a 91% increase in L-tryptophan yield in flask fermentation experiments, while acetate production decreased by 35%, compared with its parent FB-04. Throughout the fed-batch fermentation process, acetate accumulation by FB-04(pta1) was slower than that by FB-04. The final L-tryptophan titer of FB-04(pta1) reached 44.0 g/L, representing a 15% increase over that of FB-04. Metabolomics analysis showed that the pta1 genomic substitution slightly decreased carbon flux through glycolysis and significantly increased carbon fluxes through the pentose phosphate and common aromatic pathways. These results indicate that this strategy enhances L-tryptophan production and decreases acetate accumulation during the L-tryptophan fermentation process.
[Mh] Termos MeSH primário: Acetato Quinase/metabolismo
Escherichia coli/metabolismo
Redes e Vias Metabólicas
Fosfato Acetiltransferase/metabolismo
Triptofano/biossíntese
[Mh] Termos MeSH secundário: Acetato Quinase/genética
Acetatos/metabolismo
Carbono/metabolismo
Ativação Enzimática
Escherichia coli/genética
Fermentação
Deleção de Genes
Metaboloma
Metabolômica/métodos
Mutação
Fosfato Acetiltransferase/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetates); 7440-44-0 (Carbon); 8DUH1N11BX (Tryptophan); EC 2.3.1.8 (Phosphate Acetyltransferase); EC 2.7.2.1 (Acetate Kinase)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170724
[Lr] Data última revisão:
170724
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160628
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0158200


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[PMID]:26975873
[Au] Autor:Marshall DD; Sadykov MR; Thomas VC; Bayles KW; Powers R
[Ad] Endereço:Department of Chemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States.
[Ti] Título:Redox Imbalance Underlies the Fitness Defect Associated with Inactivation of the Pta-AckA Pathway in Staphylococcus aureus.
[So] Source:J Proteome Res;15(4):1205-12, 2016 Apr 01.
[Is] ISSN:1535-3907
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The phosphotransacetylase-acetate kinase (Pta-AckA) pathway is thought to be a vital ATP generating pathway for Staphylococcus aureus. Disruption of the Pta-AckA pathway during overflow metabolism causes significant reduction in growth rate and viability, albeit not due to intracellular ATP depletion. Here, we demonstrate that toxicity associated with inactivation of the Pta-AckA pathway resulted from an altered intracellular redox environment. Growth of the pta and ackA mutants under anaerobic conditions partially restored cell viability. NMR metabolomics analyses and (13)C6-glucose metabolism tracing experiments revealed the activity of multiple pathways that promote redox (NADH/NAD(+)) turnover to be enhanced in the pta and ackA mutants during anaerobic growth. Restoration of redox homeostasis in the pta mutant by overexpressing l- lactate dehydrogenase partially restored its viability under aerobic conditions. Together, our findings suggest that during overflow metabolism, the Pta-AckA pathway plays a critical role in preventing cell viability defects by promoting intracellular redox homeostasis.
[Mh] Termos MeSH primário: Acetato Quinase/genética
Proteínas de Bactérias/genética
Regulação Bacteriana da Expressão Gênica
Metabolômica
Fosfato Acetiltransferase/genética
Staphylococcus aureus/genética
[Mh] Termos MeSH secundário: Acetato Quinase/deficiência
Trifosfato de Adenosina/biossíntese
Aerobiose
Anaerobiose
Proteínas de Bactérias/metabolismo
Isótopos de Carbono
Glucose/metabolismo
Homeostase
L-Lactato Desidrogenase/metabolismo
Espectroscopia de Ressonância Magnética
Viabilidade Microbiana
Mutação
NAD/metabolismo
Oxirredução
Fosfato Acetiltransferase/deficiência
Staphylococcus aureus/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 (Carbon Isotopes); 0U46U6E8UK (NAD); 8L70Q75FXE (Adenosine Triphosphate); EC 1.1.1.27 (L-Lactate Dehydrogenase); EC 2.3.1.8 (Phosphate Acetyltransferase); EC 2.7.2.1 (Acetate Kinase); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:170403
[Lr] Data última revisão:
170403
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160316
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jproteome.5b01089


  6 / 227 MEDLINE  
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[PMID]:26922831
[Au] Autor:Pineda E; Vázquez C; Encalada R; Nozaki T; Sato E; Hanadate Y; Néquiz M; Olivos-García A; Moreno-Sánchez R; Saavedra E
[Ad] Endereço:Departamento de Bioquímica, Instituto Nacional de Cardiología Ignacio Chávez. Mexico D.F. 14080, Mexico.
[Ti] Título:Roles of acetyl-CoA synthetase (ADP-forming) and acetate kinase (PPi-forming) in ATP and PPi supply in Entamoeba histolytica.
[So] Source:Biochim Biophys Acta;1860(6):1163-72, 2016 Jun.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Acetate is an end-product of the PPi-dependent fermentative glycolysis in Entamoeba histolytica; it is synthesized from acetyl-CoA by ADP-forming acetyl-CoA synthetase (ACS) with net ATP synthesis or from acetyl-phosphate by a unique PPi-forming acetate kinase (AcK). The relevance of these enzymes to the parasite ATP and PPi supply, respectively, are analyzed here. METHODS: The recombinant enzymes were kinetically characterized and their physiological roles were analyzed by transcriptional gene silencing and further metabolic analyses in amoebae. RESULTS: Recombinant ACS showed higher catalytic efficiencies (Vmax/Km) for acetate formation than for acetyl-CoA formation and high acetyl-CoA levels were found in trophozoites. Gradual ACS gene silencing (49-93%) significantly decreased the acetate flux without affecting the levels of glycolytic metabolites and ATP in trophozoites. However, amoebae lacking ACS activity were unable to reestablish the acetyl-CoA/CoA ratio after an oxidative stress challenge. Recombinant AcK showed activity only in the acetate formation direction; however, its substrate acetyl-phosphate was undetected in axenic parasites. AcK gene silencing did not affect acetate production in the parasites but promoted a slight decrease (10-20%) in the hexose phosphates and PPi levels. CONCLUSIONS: These results indicated that the main role of ACS in the parasite energy metabolism is not ATP production but to recycle CoA for glycolysis to proceed under aerobic conditions. AcK does not contribute to acetate production but might be marginally involved in PPi and hexosephosphate homeostasis. SIGNIFICANCE: The previous, long-standing hypothesis that these enzymes importantly contribute to ATP and PPi supply in amoebae can now be ruled out.
[Mh] Termos MeSH primário: Acetato Quinase/fisiologia
Acetato-CoA Ligase/fisiologia
Difosfatos/metabolismo
Entamoeba histolytica/metabolismo
[Mh] Termos MeSH secundário: Acetato Quinase/genética
Acetato-CoA Ligase/genética
Acetatos/metabolismo
Trifosfato de Adenosina/metabolismo
Metabolismo Energético
Etanol/metabolismo
Glicólise
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Acetates); 0 (Diphosphates); 3K9958V90M (Ethanol); 4E862E7GRQ (diphosphoric acid); 8L70Q75FXE (Adenosine Triphosphate); EC 2.7.2.1 (Acetate Kinase); EC 6.2.1.1 (Acetate-CoA Ligase)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:161126
[Lr] Data última revisão:
161126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160301
[St] Status:MEDLINE


  7 / 227 MEDLINE  
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[PMID]:26448059
[Au] Autor:Moore TC; Escalante-Semerena JC
[Ad] Endereço:Department of Microbiology, University of Georgia, 120 Cedar Street, Athens, GA, 30602, USA.
[Ti] Título:The EutQ and EutP proteins are novel acetate kinases involved in ethanolamine catabolism: physiological implications for the function of the ethanolamine metabolosome in Salmonella enterica.
[So] Source:Mol Microbiol;99(3):497-511, 2016 Feb.
[Is] ISSN:1365-2958
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Salmonella enterica catabolizes ethanolamine inside a compartment known as the metabolosome. The ethanolamine utilization (eut) operon of this bacterium encodes all functions needed for the assembly and function of this structure. To date, the roles of EutQ and EutP were not known. Herein we show that both proteins have acetate kinase activity and that EutQ is required during anoxic growth of S. enterica on ethanolamine and tetrathionate. EutP and EutQ-dependent ATP synthesis occurred when enzymes were incubated with ADP, Mg(II) ions and acetyl-phosphate. EutQ and EutP also synthesized acetyl-phosphate from ATP and acetate. Although EutP had acetate kinase activity, ΔeutP strains lacked discernible phenotypes under the conditions where ΔeutQ strains displayed clear phenotypes. The kinetic parameters indicate that EutP is a faster enzyme than EutQ. Our evidence supports the conclusion that EutQ and EutP represent novel classes of acetate kinases. We propose that EutQ is necessary to drive flux through the pathway under physiological conditions, preventing a buildup of acetaldehyde. We also suggest that ATP generated by these enzymes may be used as a substrate for EutT, the ATP-dependent corrinoid adenosyltransferase and for the EutA ethanolamine ammonia-lyase reactivase.
[Mh] Termos MeSH primário: Acetato Quinase/metabolismo
Proteínas de Bactérias/metabolismo
Etanolamina/metabolismo
Salmonella typhimurium/enzimologia
[Mh] Termos MeSH secundário: Acetato Quinase/química
Acetato Quinase/genética
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Cinética
Salmonella typhimurium/genética
Salmonella typhimurium/crescimento & desenvolvimento
Salmonella typhimurium/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Bacterial Proteins); 5KV86114PT (Ethanolamine); EC 2.7.2.1 (Acetate Kinase)
[Em] Mês de entrada:1610
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151009
[St] Status:MEDLINE
[do] DOI:10.1111/mmi.13243


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[PMID]:26370798
[Au] Autor:Zhang J; Qian Y; Ding Q; Ou L
[Ad] Endereço:State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, P.R. China.
[Ti] Título:Enzymatic Manufacture of Deoxythymidine-5'-Triphosphate with Permeable Intact Cells of E. coli Coexpressing Thymidylate Kinase and Acetate Kinase.
[So] Source:J Microbiol Biotechnol;25(12):2034-42, 2015 Dec 28.
[Is] ISSN:1738-8872
[Cp] País de publicação:Korea (South)
[La] Idioma:eng
[Ab] Resumo:A one-pot process of enzymatic synthesis of deoxythymidine-5'-triphosphate (5'-dTTP) employing whole cells of recombinant Escherichia coli coexpressing thymidylate kinase (TMKase) and acetate kinase (ACKase) was developed. Genes tmk and ack from E. coli were cloned and inserted into pET28a(+), and then transduced into E. coli BL21 (DE3) to form recombinant strain pTA in which TMKase and ACKase were simultaneously overexpressed. It was found that the relative residual specific activities of TMKase and ACKase, in pTA pretreated with 20 mM ethylene diamine tetraacetic acid (EDTA) at 25°C for 30 min, were 94% and 96%, respectively. The yield of 5'-dTTP reached above 94% from 5 mM deoxythymidine 5'-monophosphate (5'-dTMP) and 15 mM acetyl phosphate catalyzed with intact cells of pTA pretreated with EDTA. The process was so effective that only 0.125 mM adenosine-5'- triphosphate was sufficient to deliver the phosphate group from acetyl phosphate to dTMP and dTDP.
[Mh] Termos MeSH primário: Acetato Quinase/metabolismo
Escherichia coli/enzimologia
Escherichia coli/metabolismo
Engenharia Metabólica/métodos
Núcleosídeo-Fosfato Quinase/metabolismo
Nucleotídeos de Timina/metabolismo
[Mh] Termos MeSH secundário: Acetato Quinase/genética
Escherichia coli/genética
Expressão Gênica
Núcleosídeo-Fosfato Quinase/genética
Organofosfatos/metabolismo
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Temperatura Ambiente
Timidina Monofosfato/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Organophosphates); 0 (Recombinant Proteins); 0 (Thymine Nucleotides); 365-07-1 (Thymidine Monophosphate); 590-54-5 (acetyl phosphate); EC 2.7.2.1 (Acetate Kinase); EC 2.7.4.4 (Nucleoside-Phosphate Kinase); EC 2.7.4.9 (dTMP kinase); QOP4K539MU (thymidine 5'-triphosphate)
[Em] Mês de entrada:1610
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150916
[St] Status:MEDLINE
[do] DOI:10.4014/jmb.1506.06020


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[PMID]:26275877
[Au] Autor:Rozova ON; Khmelenina VN; Gavletdinova JZ; Mustakhimov II; Trotsenko YA
[Ad] Endereço:Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Prospect Nauki 5, Pushchino, 142290, Russia, rozovaolga1@rambler.ru.
[Ti] Título:Acetate kinase-an enzyme of the postulated phosphoketolase pathway in Methylomicrobium alcaliphilum 20Z.
[So] Source:Antonie Van Leeuwenhoek;108(4):965-74, 2015 Oct.
[Is] ISSN:1572-9699
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Recombinant acetate kinase (AcK) was obtained from the aerobic haloalkalitolerant methanotroph Methylomicrobium alcaliphilum 20Z by heterologous expression in Escherichia coli and purification by affinity chromatography. The substrate specificity, the kinetics and oligomeric state of the His6-tagged AcK were determined. The M. alcaliphilum AcK (2 × 45 kDa) catalyzed the reversible phosphorylation of acetate into acetyl phosphate and exhibited a dependence on Mg(2+) or Mn(2+) ions and strong specificity to ATP/ADP. The enzyme showed the maximal activity and high stability at 70 °C. AcK was 20-fold more active in the reaction of acetate synthesis compared to acetate phosphorylation and had a higher affinity to acetyl phosphate (K m 0.11 mM) than to acetate (K m 5.6 mM). The k cat /K m ratios indicated that the enzyme had a remarkably high catalytic efficiency for acetate and ATP formation (k cat/K m = 1.7 × 10(6)) compared to acetate phosphorylation (k cat/K m = 2.5 × 10(3)). The ack gene of M. alcaliphilum 20Z was shown to be co-transcribed with the xfp gene encoding putative phosphoketolase. The Blast analysis revealed the ack and xfp genes in most genomes of the sequenced aerobic methanotrophs, as well as methylotrophic bacteria not growing on methane. The distribution and metabolic role of the postulated phosphoketolase shunted glycolytic pathway in aerobic C1-utilizing bacteria is discussed.
[Mh] Termos MeSH primário: Acetato Quinase/metabolismo
Aldeído Liases/metabolismo
Redes e Vias Metabólicas/genética
Methylococcaceae/enzimologia
[Mh] Termos MeSH secundário: Acetato Quinase/química
Acetato Quinase/genética
Cromatografia de Afinidade
Clonagem Molecular
Coenzimas/análise
Estabilidade Enzimática
Escherichia coli/genética
Escherichia coli/metabolismo
Perfilação da Expressão Gênica
Cinética
Methylococcaceae/genética
Proteínas Recombinantes/genética
Proteínas Recombinantes/isolamento & purificação
Proteínas Recombinantes/metabolismo
Homologia de Sequência
Especificidade por Substrato
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Coenzymes); 0 (Recombinant Proteins); EC 2.7.2.1 (Acetate Kinase); EC 4.1.2.- (Aldehyde-Lyases); EC 4.1.2.9 (phosphoketolase)
[Em] Mês de entrada:1605
[Cu] Atualização por classe:150909
[Lr] Data última revisão:
150909
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150816
[St] Status:MEDLINE
[do] DOI:10.1007/s10482-015-0549-5


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[PMID]:26235787
[Au] Autor:Barnhart EP; McClure MA; Johnson K; Cleveland S; Hunt KA; Fields MW
[Ad] Endereço:1] Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA [2] Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA [3] US Geological Survey, Helena, MT, USA.
[Ti] Título:Potential Role of Acetyl-CoA Synthetase (acs) and Malate Dehydrogenase (mae) in the Evolution of the Acetate Switch in Bacteria and Archaea.
[So] Source:Sci Rep;5:12498, 2015 Aug 03.
[Is] ISSN:2045-2322
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Although many Archaea have AMP-Acs (acetyl-coenzyme A synthetase) and ADP-Acs, the extant methanogenic genus Methanosarcina is the only identified Archaeal genus that can utilize acetate via acetate kinase (Ack) and phosphotransacetylase (Pta). Despite the importance of ack as the potential urkinase in the ASKHA phosphotransferase superfamily, an origin hypothesis does not exist for the acetate kinase in Bacteria, Archaea, or Eukarya. Here we demonstrate that Archaeal AMP-Acs and ADP-Acs contain paralogous ATPase motifs previously identified in Ack, which demonstrate a novel relation between these proteins in Archaea. The identification of ATPase motif conservation and resulting structural features in AMP- and ADP-acetyl-CoA synthetase proteins in this study expand the ASKHA superfamily to include acetyl-CoA synthetase. Additional phylogenetic analysis showed that Pta and MaeB sequences had a common ancestor, and that the Pta lineage within the halophilc archaea was an ancestral lineage. These results suggested that divergence of a duplicated maeB within an ancient halophilic, archaeal lineage formed a putative pta ancestor. These results provide a potential scenario for the establishment of the Ack/Pta pathway and provide novel insight into the evolution of acetate metabolism for all three domains of life.
[Mh] Termos MeSH primário: Acetato-CoA Ligase/metabolismo
Acetatos/metabolismo
Proteínas Arqueais/química
Proteínas de Bactérias/química
Evolução Biológica
Malato Desidrogenase/metabolismo
[Mh] Termos MeSH secundário: Acetato Quinase/química
Acetato Quinase/metabolismo
Acetato-CoA Ligase/química
Acetato-CoA Ligase/genética
Motivos de Aminoácidos
Sequência de Aminoácidos
Proteínas Arqueais/genética
Proteínas Arqueais/metabolismo
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Sequência Conservada
Evolução Molecular
Halobacteriales/enzimologia
Halobacteriales/genética
Malato Desidrogenase/química
Malato Desidrogenase/genética
Methanosarcina/genética
Methanosarcina/metabolismo
Fosfato Acetiltransferase/química
Fosfato Acetiltransferase/metabolismo
Filogenia
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Acetates); 0 (Archaeal Proteins); 0 (Bacterial Proteins); EC 1.1.1.37 (Malate Dehydrogenase); EC 2.3.1.8 (Phosphate Acetyltransferase); EC 2.7.2.1 (Acetate Kinase); EC 6.2.1.1 (Acetate-CoA Ligase)
[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:150804
[St] Status:MEDLINE
[do] DOI:10.1038/srep12498



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