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[PMID]: 28470425 [Au] Autor: Ranawat P; Rawat S [Ad] Endereço: Department of Botany and Microbiology, Hemvati Nandan Bahuguna Garhwal University, Srinagar (Garhwal), Uttrakhand, India. [Ti] Título: Radiation resistance in thermophiles: mechanisms and applications. [So] Source: World J Microbiol Biotechnol;33(6):112, 2017 Jun. [Is] ISSN: 1573-0972 [Cp] País de publicação: Germany [La] Idioma: eng [Ab] Resumo: The study of prokaryotic life in high temperature environments viz., geothermal areas, hot, acidic geysers and undersea hydrothermal vents has revealed the existence of thermophiles (or hyperthermophiles). These microorganisms possess various stress adaptation mechanisms which enable them to bypass multiple physical and chemical barriers for survival. The discovery of radiation resistant thermophile Deinococcus geothermalis has given new insights into the field of radiation microbiology. The ability of radiation resistant thermophiles to deal with the lethal effects of ionizing radiations like DNA damage, oxidative bursts and protein damage has made them a model system for exobiology and interplanetary transmission of life. They might be an antiquity of historical transport process that brought microbial life on Earth. These radiation resistant thermophiles are resistant to desiccation as well and maintain their homeostasis by advance DNA repair mechanisms, reactive oxygen species (ROS) detoxification system and accumulation of compatible solutes. Moreover, engineered radioresistant thermophilic strains are the best candidate for bioremediation of radionuclide waste while the extremolytes produced by these organisms may have predicted therapeutic uses. So, the present article delineate a picture of radiation resistance thermophiles, their adaptive mechanisms to evade stress viz., radiation and desiccation, their present applications along with new horizons in near future. [Mh] Termos MeSH primário: Archaea/fisiologia Archaea/efeitos da radiação Bactérias/efeitos da radiação Fenômenos Fisiológicos Bacterianos/efeitos da radiação Temperatura Alta [Mh] Termos MeSH secundário: Actinobacteria/fisiologia Actinobacteria/efeitos da radiação Bactérias/genética Fenômenos Fisiológicos Bacterianos/genética Biodegradação Ambiental Cianobactérias/fisiologia Cianobactérias/efeitos da radiação Dano ao DNA/efeitos da radiação Reparo do DNA Deinococcus/genética Deinococcus/fisiologia Deinococcus/efeitos da radiação Microbiologia Ambiental Exobiologia Halobacterium/fisiologia Halobacterium/efeitos da radiação Pyrococcus/fisiologia Pyrococcus/efeitos da radiação Radiação Ionizante Espécies Reativas de Oxigênio/efeitos da radiação Explosão Respiratória/efeitos da radiação Estresse Fisiológico Sulfolobus/fisiologia Sulfolobus/efeitos da radiação Thermococcus/fisiologia Thermococcus/efeitos da radiação [Pt] Tipo de publicação: JOURNAL ARTICLE; REVIEW [Nm] Nome de substância: 0 (Reactive Oxygen Species) [Em] Mês de entrada: 1712 [Cu] Atualização por classe: 171201 [Lr] Data última revisão: 171201 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170505 [St] Status: MEDLINE [do] DOI: 10.1007/s11274-017-2279-5

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[PMID]: 28965803 [Au] Autor: Sui Y; Fu X; Wang Y; Hu W; Zhang T; Liu W; Jiang L; Xing S; Fu X; Xu X [Ad] Endereço: Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, PR China. [Ti] Título: Expression, purification and characterization of a catalytic domain of human protein tyrosine phosphatase non-receptor 12 (PTPN12) in Escherichia coli with FKBP-type PPIase as a chaperon. [So] Source: Protein Expr Purif;142:45-52, 2018 Feb. [Is] ISSN: 1096-0279 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Protein tyrosine phosphatase non-receptor type 12 (PTPN12), also known as PTP-PEST, was broadly expressed in hemopoietic cells. Recent research has shown that this enzyme is involved in tumorigenesis, as well as in tumor progression and transfer, as it can suppress multiple oncogenic tyrosine kinases. However, the difficulty of soluble expression of PTP-PEST in prokaryotic cells has resulted in great limitations in investigating its structure and functions. In this study, we successfully carried out soluble expression of the catalytic domain of PTP-PEST (ΔPTP-PEST) in Escherichia coli and performed an enzymatic characterization and kinetics. To confirm expression efficiency, we also induced the expression of the chaperon, FKBP_C. FKBP_C expression indicated efficacious prokaryotic expression of ΔPTP-PEST. In conclusion, our work yielded a practical expression system and two-step chromatography purification method that may serve as a valuable tool for the structural and functional analysis of proteins that are difficult to express in the soluble form in prokaryotic cells. [Mh] Termos MeSH primário: Proteínas Arqueais/genética Chaperonas Moleculares/genética Peptidilprolil Isomerase/genética Proteína Tirosina Fosfatase não Receptora Tipo 12/genética Proteínas de Ligação a Tacrolimo/genética Thermococcus/química [Mh] Termos MeSH secundário: Proteínas Arqueais/metabolismo Domínio Catalítico Clonagem Molecular Escherichia coli/genética Escherichia coli/metabolismo Expressão Gênica Seres Humanos Cinética Chaperonas Moleculares/metabolismo Peptidilprolil Isomerase/metabolismo Plasmídeos/química Plasmídeos/metabolismo Proteína Tirosina Fosfatase não Receptora Tipo 12/isolamento & purificação Proteína Tirosina Fosfatase não Receptora Tipo 12/metabolismo Proteínas Recombinantes de Fusão/genética Proteínas Recombinantes de Fusão/metabolismo Proteínas de Ligação a Tacrolimo/metabolismo Thermococcus/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Archaeal Proteins); 0 (Molecular Chaperones); 0 (Recombinant Fusion Proteins); EC 3.1.3.48 (PTPN12 protein, human); EC 3.1.3.48 (Protein Tyrosine Phosphatase, Non-Receptor Type 12); EC 5.2.1.- (Tacrolimus Binding Proteins); EC 5.2.1.8 (Peptidylprolyl Isomerase) [Em] Mês de entrada: 1711 [Cu] Atualização por classe: 171128 [Lr] Data última revisão: 171128 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 171003 [St] Status: MEDLINE

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[PMID]: 28977567 [Au] Autor: Nagata M; Ishino S; Yamagami T; Ogino H; Simons JR; Kanai T; Atomi H; Ishino Y [Ad] Endereço: Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Fukuoka 812-8581, Japan. [Ti] Título: The Cdc45/RecJ-like protein forms a complex with GINS and MCM, and is important for DNA replication in Thermococcus kodakarensis. [So] Source: Nucleic Acids Res;45(18):10693-10705, 2017 Oct 13. [Is] ISSN: 1362-4962 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: The archaeal minichromosome maintenance (MCM) has DNA helicase activity, which is stimulated by GINS in several archaea. In the eukaryotic replicative helicase complex, Cdc45 forms a complex with MCM and GINS, named as CMG (Cdc45-MCM-GINS). Cdc45 shares sequence similarity with bacterial RecJ. A Cdc45/RecJ-like protein from Thermococcus kodakarensis shows a bacterial RecJ-like exonuclease activity, which is stimulated by GINS in vitro. Therefore, this archaeal Cdc45/RecJ is designated as GAN, from GINS-associated nuclease. In this study, we identified the CMG-like complex in T. kodakarensis cells. The GAN·GINS complex stimulated the MCM helicase, but MCM did not affect the nuclease activity of GAN in vitro. The gene disruption analysis showed that GAN was non-essential for its viability but the Δgan mutant did not grow at 93°C. Furthermore, the Δgan mutant showed a clear retardation in growth as compared with the parent cells under optimal conditions at 85°C. These deficiencies were recovered by introducing the gan gene encoding the nuclease deficient GAN protein back to the genome. These results suggest that the replicative helicase complex without GAN may become unstable and ineffective in replication fork progression. The nuclease activity of GAN is not related to the growth defects of the Δgan mutant cells. [Mh] Termos MeSH primário: Proteínas Arqueais/metabolismo Replicação do DNA Exodesoxirribonucleases/metabolismo Componente 3 do Complexo de Manutenção de Minicromossomo/metabolismo Thermococcus/enzimologia Thermococcus/genética [Mh] Termos MeSH secundário: Proteínas Arqueais/genética Exodesoxirribonucleases/genética Deleção de Genes Metais Thermococcus/crescimento & desenvolvimento Thermococcus/metabolismo Raios Ultravioleta [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Archaeal Proteins); 0 (Metals); EC 3.1.- (Exodeoxyribonucleases); EC 3.6.4.12 (Minichromosome Maintenance Complex Component 3) [Em] Mês de entrada: 1711 [Cu] Atualização por classe: 171107 [Lr] Data última revisão: 171107 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 171005 [St] Status: MEDLINE [do] DOI: 10.1093/nar/gkx740

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[PMID]: 28918746 [Au] Autor: Muhammad MA; Falak S; Rashid N; Gardner QA; Ahmad N; Imanaka T; Akhtar M [Ad] Endereço: University of the Punjab, School of Biological Sciences, Lahore, 54590, Pakistan. naeem.ff.sbs@pu.edu.pk. [Ti] Título: Escherichia coli Signal Peptidase Recognizes and Cleaves Archaeal Signal Sequence. [So] Source: Biochemistry (Mosc);82(7):821-825, 2017 Jul. [Is] ISSN: 1608-3040 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Tk1884, an open reading frame encoding α-amylase in Thermococcus kodakarensis, was cloned with the native signal sequence and expressed in Escherichia coli. Heterologous gene expression resulted in secretion of the recombinant protein to the extracellular culture medium. Extracellular α-amylase activity gradually increased after induction. Tk1884 was purified from the extracellular medium, and its molecular mass determined by electrospray ionization mass spectrometry indicated the cleavage of a few amino acids. The N-terminal amino acid sequence of the purified Tk1884 was determined, which revealed that the signal peptide was cleaved between Ala26 and Ala27 by E. coli signal peptidase. To the best of our knowledge, this is the first report describing an archaeal signal sequence recognized and cleaved by E. coli signal peptidase. [Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo Escherichia coli/metabolismo Proteínas de Membrana/metabolismo Serina Endopeptidases/metabolismo [Mh] Termos MeSH secundário: Proteínas Arqueais/química Proteínas Arqueais/genética Proteínas Arqueais/metabolismo Clonagem Molecular Ensaios Enzimáticos Peso Molecular Proteínas Recombinantes/biossíntese Proteínas Recombinantes/química Proteínas Recombinantes/isolamento & purificação Espectrometria de Massas por Ionização por Electrospray Thermococcus/enzimologia alfa-Amilases/química alfa-Amilases/genética alfa-Amilases/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Archaeal Proteins); 0 (Bacterial Proteins); 0 (Membrane Proteins); 0 (Recombinant Proteins); EC 3.2.1.1 (alpha-Amylases); EC 3.4.21.- (Serine Endopeptidases); EC 3.4.21.89 (type I signal peptidase) [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: 170919 [St] Status: MEDLINE [do] DOI: 10.1134/S0006297917070070

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[PMID]: 28876238 [Au] Autor: Larson SB; McPherson A [Ad] Endereço: Department of Molecular Biology and Biochemistry, University of California, 530A Steinhaus Hall, Irvine, CA 92697-3900, USA. [Ti] Título: The structure of the Pfp1 protease from the hyperthermophilic archaeon Thermococcus thioreducens in two crystal forms. [So] Source: Acta Crystallogr D Struct Biol;73(Pt 9):749-756, 2017 Sep 01. [Is] ISSN: 2059-7983 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: The Pfp1 protease, a cysteine protease of unknown specificity from the hyperthermophilic archaeon Thermococcus thioreducens, was crystallized in two distinctive crystal forms: from concentrated citrate in one case and PEG in the other. X-ray data were collected from both crystal forms at room temperature to about 1.9 Šresolution using a laboratory source and detector, and the structures were solved by molecular replacement using the Pfp1 protease from Pyrococcus horikoshii as the search model. In the T. thioreducens protease structures, Cys18 residues on adjacent molecules in the asymmetric units form intermolecular disulfide bonds, thereby yielding hexamers composed of three cross-linked, quasi-dyad-related dimers with crystallographically exact threefold axes and exhibiting almost exact 32 symmetry. The corresponding residue in P. horikoshii Pfp1 is Tyr18. An individual active site containing Cys100 and His101 also includes a Glu74 residue contributed by a quasi-twofold-related, non-cross-linked subunit. Two catalytic triads are therefore closely juxtaposed about the quasi-twofold axis at the interface of these subunits, and are relatively sequestered within the hexamer cavity. The cysteine in the active site is observed to be oxidized in both of the crystal forms that were studied. [Mh] Termos MeSH primário: Cisteína Proteases/química Thermococcus/enzimologia [Mh] Termos MeSH secundário: Domínio Catalítico Cristalografia por Raios X Modelos Moleculares Conformação Proteica Multimerização Proteica Thermococcus/química [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: EC 3.4.- (Cysteine Proteases) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 170913 [Lr] Data última revisão: 170913 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170907 [St] Status: MEDLINE [do] DOI: 10.1107/S2059798317010622

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[PMID]: 28832623 [Au] Autor: Huber C; Marx A [Ad] Endereço: Department of Chemistry, University of Konstanz, Konstanz, Germany. [Ti] Título: Variants of sequence family B Thermococcus kodakaraensis DNA polymerase with increased mismatch extension selectivity. [So] Source: PLoS One;12(8):e0183623, 2017. [Is] ISSN: 1932-6203 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Fidelity and selectivity of DNA polymerases are critical determinants for the biology of life, as well as important tools for biotechnological applications. DNA polymerases catalyze the formation of DNA strands by adding deoxynucleotides to a primer, which is complementarily bound to a template. To ensure the integrity of the genome, DNA polymerases select the correct nucleotide and further extend the nascent DNA strand. Thus, DNA polymerase fidelity is pivotal for ensuring that cells can replicate their genome with minimal error. DNA polymerases are, however, further optimized for more specific biotechnological or diagnostic applications. Here we report on the semi-rational design of mutant libraries derived by saturation mutagenesis at single sites of a 3'-5'-exonuclease deficient variant of Thermococcus kodakaraensis DNA polymerase (KOD pol) and the discovery for variants with enhanced mismatch extension selectivity by screening. Sites of potential interest for saturation mutagenesis were selected by their proximity to primer or template strands. The resulting libraries were screened via quantitative real-time PCR. We identified three variants with single amino acid exchanges-R501C, R606Q, and R606W-which exhibited increased mismatch extension selectivity. These variants were further characterized towards their potential in mismatch discrimination. Additionally, the identified enzymes were also able to differentiate between cytosine and 5-methylcytosine. Our results demonstrate the potential in characterizing and developing DNA polymerases for specific PCR based applications in DNA biotechnology and diagnostics. [Mh] Termos MeSH primário: Pareamento Incorreto de Bases DNA Polimerase Dirigida por DNA/metabolismo Thermococcus/enzimologia [Mh] Termos MeSH secundário: 5-Metilcitosina/metabolismo DNA Polimerase Dirigida por DNA/genética Cinética Reação em Cadeia da Polimerase em Tempo Real Thermococcus/genética [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 6R795CQT4H (5-Methylcytosine); EC 2.7.7.7 (DNA-Directed DNA Polymerase) [Em] Mês de entrada: 1710 [Cu] Atualização por classe: 171019 [Lr] Data última revisão: 171019 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170824 [St] Status: MEDLINE [do] DOI: 10.1371/journal.pone.0183623

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[PMID]: 28778390 [Au] Autor: Yasukawa K; Iida K; Okano H; Hidese R; Baba M; Yanagihara I; Kojima K; Takita T; Fujiwara S [Ad] Endereço: Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan. Electronic address: yasukawa@kais.kyoto-u.ac.jp. [Ti] Título: Next-generation sequencing-based analysis of reverse transcriptase fidelity. [So] Source: Biochem Biophys Res Commun;492(2):147-153, 2017 Oct 14. [Is] ISSN: 1090-2104 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: In this study, we devised a simple and rapid method to analyze fidelity of reverse transcriptase (RT) using next-generation sequencing (NGS). The method comprises a cDNA synthesis reaction from standard RNA with a primer containing a tag of 14 randomized bases and the RT to be tested, PCR using high-fidelity DNA polymerase, and NGS. By comparing the sequence of each read with the reference sequence, mutations were identified. The mutation can be identified to be due to an error introduced by either cDNA synthesis, PCR, or NGS based on whether the sequence reads with the same tag contain the same mutation or not. The error rates in cDNA synthesis with Moloney murine leukemia virus (MMLV) RT thermostable variant MM4 or the recently developed 16-tuple variant of family B DNA polymerase with RT activity, RTX, from Thermococcus kodakarensis, were 0.75-1.0 × 10 errors/base, while that in the reaction with the wild-type human immunodeficiency virus type 1 (HIV-1) RT was 2.6 × 10 errors/base. Overall, our method could precisely evaluate the fidelity of various RTs with different reaction conditions in a high-throughput manner without the use of expensive optics and troublesome adaptor ligation. [Mh] Termos MeSH primário: DNA Complementar/genética HIV-1/enzimologia Sequenciamento de Nucleotídeos em Larga Escala/métodos Vírus da Leucemia Murina de Moloney/enzimologia DNA Polimerase Dirigida por RNA/genética Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos Thermococcus/enzimologia [Mh] Termos MeSH secundário: Sequência de Bases DNA Polimerase Dirigida por DNA/genética Transcriptase Reversa do HIV/genética HIV-1/genética Vírus da Leucemia Murina de Moloney/genética DNA Polimerase Dirigida por RNA/química Thermococcus/genética [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (DNA, Complementary); EC 2.7.7.- (reverse transcriptase, Human immunodeficiency virus 1); EC 2.7.7.49 (HIV Reverse Transcriptase); EC 2.7.7.49 (RNA-Directed DNA Polymerase); EC 2.7.7.7 (DNA-Directed DNA Polymerase) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 170925 [Lr] Data última revisão: 170925 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170806 [St] Status: MEDLINE

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[PMID]: 28678603 [Au] Autor: Hidese R; Im KH; Kobayashi M; Niitsu M; Furuchi T; Fujiwara S [Ad] Endereço: a Department of Bioscience, Graduate School of Science and Technology , Kwansei-Gakuin University , Hyogo , Japan. [Ti] Título: Identification of a novel acetylated form of branched-chain polyamine from a hyperthermophilic archaeon Thermococcus kodakarensis. [So] Source: Biosci Biotechnol Biochem;81(9):1845-1849, 2017 Sep. [Is] ISSN: 1347-6947 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Long/branched-chain polyamines are unique polycations found in thermophiles. The hyperthermophilic archaeon Thermococcus kodakarensis contains spermidine and a branched-chain polyamine, N -bis(aminopropyl)spermidine, as major polyamines. The metabolic pathways associated with branched-chain polyamines remain unknown. Here, we used gas chromatography and liquid chromatography-tandem mass spectrometry analyses to identify a new acetylated polyamine, N -bis(aminopropyl)-N -acetylspermidine, from T. kodakarensis; this polyamine was not found in other micro-organisms. The amounts of branched-chain polyamine and its acetylated form increased with temperature, indicating that branched-chain polyamines are important for growth at higher temperatures. The amount of quaternary acetylated polyamine produced was associated with the amount of N -bis(aminopropyl)spermidine in the cell. The ratio of acetylated to non-acetylated forms was higher in the stationary phase than in the logarithmic growth phase under high-temperature stress condition. [Mh] Termos MeSH primário: Poliaminas/metabolismo Temperatura Ambiente Thermococcus/metabolismo [Mh] Termos MeSH secundário: Acetilação Espaço Intracelular/metabolismo Poliaminas/química Poliaminas/isolamento & purificação Thermococcus/citologia Thermococcus/fisiologia [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Polyamines) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 170906 [Lr] Data última revisão: 170906 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170706 [St] Status: MEDLINE [do] DOI: 10.1080/09168451.2017.1345616

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[PMID]: 28652302 [Au] Autor: Hachisuka SI; Sato T; Atomi H [Ad] Endereço: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Japan. [Ti] Título: Metabolism Dealing with Thermal Degradation of NAD in the Hyperthermophilic Archaeon Thermococcus kodakarensis. [So] Source: J Bacteriol;199(19), 2017 Oct 01. [Is] ISSN: 1098-5530 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: NAD is an important cofactor for enzymatic oxidation reactions in all living organisms, including (hyper)thermophiles. However, NAD is susceptible to thermal degradation at high temperatures. It can thus be expected that (hyper)thermophiles harbor mechanisms that maintain NAD concentrations and possibly remove and/or reuse undesirable degradation products of NAD Here we confirmed that at 85°C, thermal degradation of NAD results mostly in the generation of nicotinamide and ADP-ribose, the latter known to display toxicity by spontaneously linking to proteins. The hyperthermophilic archaeon possesses a putative ADP-ribose pyrophosphatase (ADPR-PPase) encoded by the TK2284 gene. ADPR-PPase hydrolyzes ADP-ribose to ribose 5-phosphate (R5P) and AMP. The purified recombinant TK2284 protein exhibited activity toward ADP-ribose as well as ADP-glucose. Kinetic analyses revealed a much higher catalytic efficiency toward ADP-ribose, suggesting that ADP-ribose was the physiological substrate. To gain insight into the physiological function of TK2284, a TK2284 gene disruption strain was constructed and examined. Incubation of NAD in the cell extract of the mutant strain at 85°C resulted in higher ADP-ribose accumulation and lower AMP production compared with those in experiments with the host strain cell extract. The mutant strain also exhibited lower cell yield and specific growth rates in a synthetic amino acid medium compared with those of the host strain. The results obtained here suggest that the ADPR-PPase in is responsible for the cleavage of ADP-ribose to R5P and AMP, providing a means to utilize the otherwise dead-end product of NAD breakdown. Hyperthermophilic microorganisms living under high temperature conditions should have mechanisms that deal with the degradation of thermolabile molecules. NAD is an important cofactor for enzymatic oxidation reactions and is susceptible to thermal degradation to ADP-ribose and nicotinamide. Here we show that an ADP-ribose pyrophosphatase homolog from the hyperthermophilic archaeon converts the detrimental ADP-ribose to ribose 5-phosphate and AMP, compounds that can be directed to central carbon metabolism. This physiological role for ADP-ribose pyrophosphatases might be universal in hyperthermophiles, as their homologs are widely distributed among both hyperthermophilic bacteria and archaea. [Mh] Termos MeSH primário: NAD/metabolismo Pirofosfatases/metabolismo Thermococcus/metabolismo [Mh] Termos MeSH secundário: Adenosina Difosfato Ribose/metabolismo Carbono/metabolismo Genes Bacterianos Temperatura Alta Cinética Mutação Niacinamida/metabolismo Pirofosfatases/genética Proteínas Recombinantes/isolamento & purificação Proteínas Recombinantes/metabolismo Thermococcus/enzimologia Thermococcus/genética Thermococcus/crescimento & desenvolvimento [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Recombinant Proteins); 0U46U6E8UK (NAD); 20762-30-5 (Adenosine Diphosphate Ribose); 25X51I8RD4 (Niacinamide); 7440-44-0 (Carbon); EC 3.6.1.- (Pyrophosphatases); EC 3.6.1.13 (ADPribose pyrophosphatase) [Em] Mês de entrada: 1710 [Cu] Atualização por classe: 171003 [Lr] Data última revisão: 171003 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170628 [St] Status: MEDLINE

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[PMID]: 28551405 [Au] Autor: Lee S; Jeong H; Lee JH; Chung JM; Kim R; Yun HJ; Won J; Jung HS [Ad] Endereço: Department of Biochemistry, College of Natural Sciences, Kangwon National University, 1 Kangwondaehak-gil, Chuncheon-si, Gangwon-do, 24341, Republic of Korea. Electronic address: taeinlee2011@kangwon.ac.kr. [Ti] Título: Characterisation of conformational and functional features of alkyl hydroperoxide reductase E-like protein. [So] Source: Biochem Biophys Res Commun;489(2):217-222, 2017 Jul 22. [Is] ISSN: 1090-2104 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Alkyl hydroperoxide reductase E (AhpE) is a member of the peroxidase family of enzymes that catalyse the reduction of peroxides, however its structural and functional roles are still unclear in details. In this study, we used the Thermococcus kodakarensis AhpE-like protein as a model to investigate structure-function relationships including the molecular properties of DNA binding activity. Multiple sequence alignment, structural comparison and biochemical analyses revealed that TkAhpE includes conserved peroxidase residues in the active site, and exhibits peroxidase activity with structure-dependent holdase chaperone function. Following electrophoretic mobility shift assays and electron microscopy analysis demonstrated distinctive binding features of TkAhpE to the DNA showing that their dimeric conformer can bind to the double-stranded DNA, but not to the single-stranded DNA, indicating its striking molecular features to double-stranded DNA-specific interactions. Based on our results, we provided that TkAhpE is a multifunctional peroxidase displaying structure-dependent molecular chaperone and DNA binding activities. [Mh] Termos MeSH primário: Peroxirredoxinas/química Peroxirredoxinas/metabolismo Thermococcus/metabolismo [Mh] Termos MeSH secundário: Sequência de Aminoácidos Modelos Moleculares Conformação Proteica Alinhamento de Sequência [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: EC 1.11.1.15 (Peroxiredoxins) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 170921 [Lr] Data última revisão: 170921 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170529 [St] Status: MEDLINE

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2	and or and not		PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2
3	and or and not		PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2

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