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Reinhard Hensel - One of the best experts on this subject based on the ideXlab platform.
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Running title: Thermoproteus tenax focused transcriptional analysis
2013Co-Authors: Thermoproteus Tenax, Melanie Zaparty, Reinhard Hensel, Er Zaigler, Claudia Stamme, Bettina SiebersAbstract:In order to unravel the role of regulation on transcript level in the central carbohydrate metabolism (CCM) of Thermoproteus tenax, a focused DNA microarray was constructed by using 85 open reading frames involved in the CCM. Transcriptional analysis was performed comparing heterotrophic growth on glucose versus autotrophic growth on CO2/H2. The anaerobic, facultative heterotrophic crenarchaeum Thermoproteus tenax shows a sulfur-dependent energy metabolism and grows optimally at 86°C and pH 5.6. In addition to autotrophic growth on carbon dioxide and hydrogen (CO2/H2), heterotrophic growth was reported on various carbohydrates such as starch, glycogen or glucose (40). The combination of genomics-based and biochemical approaches revealed that T. tenax is the only archaeum currently known that uses two different pathways for carbohydrate catabolism in parallel: A reversible Embden-Meyerhof-Parnas (EMP) pathway and the catabolic, so-called branched Entner-Doudoroff (ED) pathway
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the first prokaryotic trehalose synthase complex identified in the hyperthermophilic crenarchaeon Thermoproteus tenax
PLOS ONE, 2013Co-Authors: Melanie Zaparty, Reinhard Hensel, Henner Brinkmann, Anna Hagemann, Christopher Brasen, Andrei N Lupas, Bettina SiebersAbstract:The role of the disaccharide trehalose, its biosynthesis pathways and their regulation in Archaea are still ambiguous. In Thermoproteus tenax a fused trehalose-6-phosphate synthase/phosphatase (TPSP), consisting of an N-terminal trehalose-6-phosphate synthase (TPS) and a C-terminal trehalose-6-phosphate phosphatase (TPP) domain, was identified. The tpsp gene is organized in an operon with a putative glycosyltransferase (GT) and a putative mechanosensitive channel (MSC). The T. tenax TPSP exhibits high phosphatase activity, but requires activation by the co-expressed GT for bifunctional synthase-phosphatase activity. The GT mediated activation of TPS activity relies on the fusion of both, TPS and TPP domain, in the TPSP enzyme. Activation is mediated by complex-formation in vivo as indicated by yeast two-hybrid and crude extract analysis. In combination with first evidence for MSC activity the results suggest a sophisticated stress response involving TPSP, GT and MSC in T. tenax and probably in other Thermoproteales species. The monophyletic prokaryotic TPSP proteins likely originated via a single fusion event in the Bacteroidetes with subsequent horizontal gene transfers to other Bacteria and Archaea. Furthermore, evidence for the origin of eukaryotic TPSP fusions via HGT from prokaryotes and therefore a monophyletic origin of eukaryotic and prokaryotic fused TPSPs is presented. This is the first report of a prokaryotic, archaeal trehalose synthase complex exhibiting a much more simple composition than the eukaryotic complex described in yeast. Thus, complex formation and a complex-associated regulatory potential might represent a more general feature of trehalose synthesizing proteins.
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characterization of the crispr cas subtype i a system of the hyperthermophilic crenarchaeon Thermoproteus tenax
Journal of Bacteriology, 2012Co-Authors: Andre Plagens, Britta Tjaden, Anna Hagemann, Lennart Randau, Reinhard HenselAbstract:ABSTRACT CRISPR (clustered regularly interspaced short palindromic repeats) elements and cas (CRISPR-associated) genes are widespread in Bacteria and Archaea. The CRISPR/Cas system operates as a defense mechanism against mobile genetic elements (i.e., viruses or plasmids). Here, we investigate seven CRISPR loci in the genome of the crenarchaeon Thermoproteus tenax that include spacers with significant similarity not only to archaeal viruses but also to T. tenax genes. The analysis of CRISPR RNA (crRNA) transcription reveals transcripts of a length between 50 and 130 nucleotides, demonstrating the processing of larger crRNA precursors. The organization of identified cas genes resembles CRISPR/Cas subtype I-A, and the core cas genes are shown to be arranged on two polycistronic transcripts: cascis (cas4, cas1/2, and csa1) and cascade (csa5, cas7, cas5a, cas3, cas3′, and cas8a2). Changes in the environmental parameters such as UV-light exposure or high ionic strength modulate cas gene transcription. Two reconstitution protocols were established for the production of two discrete multipartite Cas protein complexes that correspond to their operonic gene arrangement. These data provide insights into the specialized mechanisms of an archaeal CRISPR/Cas system and allow selective functional analyses of Cas protein complexes in the future.
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dna microarray analysis of central carbohydrate metabolism glycolytic gluconeogenic carbon switch in the hyperthermophilic crenarchaeum Thermoproteus tenax
Journal of Bacteriology, 2008Co-Authors: Melanie Zaparty, Reinhard Hensel, Claudia Stamme, Alexander Zaigler, Jorg Soppa, Bettina SiebersAbstract:In order to unravel the role of regulation on transcript level in central carbohydrate metabolism (CCM) of Thermoproteus tenax, a focused DNA microarray was constructed by using 85 open reading frames involved in CCM. A transcriptional analysis comparing heterotrophic growth on glucose versus autotrophic growth on CO2-H2 was performed.
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The central carbohydrate metabolism of the hyperthermophilic crenarchaeote Thermoproteus tenax: Pathways and insights into their regulation
Archives of Microbiology, 2008Co-Authors: Melanie Zaparty, Britta Tjaden, Reinhard Hensel, Bettina SiebersAbstract:Although the complexity and modifications of the archaeal central carbohydrate metabolism (CCM) are well established, the knowledge about its regulation is rather limited. The facultatively heterotrophic, hyperthermophilic crenarchaeote Thermoproteus tenax utilizes a modified version of the reversible Embden-Meyerhof-Parnas (EMP) and the catabolic, branched Entner-Doudoroff (ED) pathway for glucose metabolism. Glucose is completely oxidized to carbon dioxide via the oxidative tricarboxylic acid (TCA) cycle, which is supposedly used in the reductive direction for carbon dioxide fixation under autotrophic growth conditions. Elemental sulfur is used as final electron acceptor. The CCM of T. tenax has been well studied on protein level as well as on gene level by performing a focused transcriptional analysis (CCM DNA microarray). In contrast to the classical pathways found in Bacteria and Eucarya allosteric regulation seems to play a minor role, therefore emphasizing the important role of regulation on transcript level in T. tenax. Whereas the EMP pathway and the TCA cycle show a highly coordinated regulation on gene level, the catabolic, branched ED pathway reveals no strong regulation. The CCM pathways in T. tenax and the current understanding of their regulation are presented.
Bettina Siebers - One of the best experts on this subject based on the ideXlab platform.
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Running title: Thermoproteus tenax focused transcriptional analysis
2013Co-Authors: Thermoproteus Tenax, Melanie Zaparty, Reinhard Hensel, Er Zaigler, Claudia Stamme, Bettina SiebersAbstract:In order to unravel the role of regulation on transcript level in the central carbohydrate metabolism (CCM) of Thermoproteus tenax, a focused DNA microarray was constructed by using 85 open reading frames involved in the CCM. Transcriptional analysis was performed comparing heterotrophic growth on glucose versus autotrophic growth on CO2/H2. The anaerobic, facultative heterotrophic crenarchaeum Thermoproteus tenax shows a sulfur-dependent energy metabolism and grows optimally at 86°C and pH 5.6. In addition to autotrophic growth on carbon dioxide and hydrogen (CO2/H2), heterotrophic growth was reported on various carbohydrates such as starch, glycogen or glucose (40). The combination of genomics-based and biochemical approaches revealed that T. tenax is the only archaeum currently known that uses two different pathways for carbohydrate catabolism in parallel: A reversible Embden-Meyerhof-Parnas (EMP) pathway and the catabolic, so-called branched Entner-Doudoroff (ED) pathway
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the first prokaryotic trehalose synthase complex identified in the hyperthermophilic crenarchaeon Thermoproteus tenax
PLOS ONE, 2013Co-Authors: Melanie Zaparty, Reinhard Hensel, Henner Brinkmann, Anna Hagemann, Christopher Brasen, Andrei N Lupas, Bettina SiebersAbstract:The role of the disaccharide trehalose, its biosynthesis pathways and their regulation in Archaea are still ambiguous. In Thermoproteus tenax a fused trehalose-6-phosphate synthase/phosphatase (TPSP), consisting of an N-terminal trehalose-6-phosphate synthase (TPS) and a C-terminal trehalose-6-phosphate phosphatase (TPP) domain, was identified. The tpsp gene is organized in an operon with a putative glycosyltransferase (GT) and a putative mechanosensitive channel (MSC). The T. tenax TPSP exhibits high phosphatase activity, but requires activation by the co-expressed GT for bifunctional synthase-phosphatase activity. The GT mediated activation of TPS activity relies on the fusion of both, TPS and TPP domain, in the TPSP enzyme. Activation is mediated by complex-formation in vivo as indicated by yeast two-hybrid and crude extract analysis. In combination with first evidence for MSC activity the results suggest a sophisticated stress response involving TPSP, GT and MSC in T. tenax and probably in other Thermoproteales species. The monophyletic prokaryotic TPSP proteins likely originated via a single fusion event in the Bacteroidetes with subsequent horizontal gene transfers to other Bacteria and Archaea. Furthermore, evidence for the origin of eukaryotic TPSP fusions via HGT from prokaryotes and therefore a monophyletic origin of eukaryotic and prokaryotic fused TPSPs is presented. This is the first report of a prokaryotic, archaeal trehalose synthase complex exhibiting a much more simple composition than the eukaryotic complex described in yeast. Thus, complex formation and a complex-associated regulatory potential might represent a more general feature of trehalose synthesizing proteins.
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The Complete Genome Sequence of Thermoproteus tenax: A Physiologically Versatile Member of the Crenarchaeota
PloS one, 2011Co-Authors: Bettina Siebers, Melanie Zaparty, Britta Tjaden, Guenter Raddatz, Sonja-verena Albers, Steve D Bell, Fabian Blombach, Arnulf Kletzin, Nikos C. Kyrpides, Christa LanzAbstract:Here, we report on the complete genome sequence of the hyperthermophilic Crenarchaeum Thermoproteus tenax (strain Kra1, DSM 2078T) a type strain of the crenarchaeotal order Thermoproteales. Its circular 1.84-megabase genome harbors no extrachromosomal elements and 2,051 open reading frames are identified, covering 90.6% of the complete sequence, which represents a high coding density. Derived from the gene content, T. tenax is a representative member of the Crenarchaeota. The organism is strictly anaerobic and sulfur-dependent with optimal growth at 86°C and pH 5.6. One particular feature is the great metabolic versatility, which is not accompanied by a distinct increase of genome size or information density as compared to other Crenarchaeota. T. tenax is able to grow chemolithoautotrophically (CO2/H2) as well as chemoorganoheterotrophically in presence of various organic substrates. All pathways for synthesizing the 20 proteinogenic amino acids are present. In addition, two presumably complete gene sets for NADH:quinone oxidoreductase (complex I) were identified in the genome and there is evidence that either NADH or reduced ferredoxin might serve as electron donor. Beside the typical archaeal A0A1-ATP synthase, a membrane-bound pyrophosphatase is found, which might contribute to energy conservation. Surprisingly, all genes required for dissimilatory sulfate reduction are present, which is confirmed by growth experiments. Mentionable is furthermore, the presence of two proteins (ParA family ATPase, actin-like protein) that might be involved in cell division in Thermoproteales, where the ESCRT system is absent, and of genes involved in genetic competence (DprA, ComF) that is so far unique within Archaea.
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The complete genome sequence of Thermoproteus tenax: a physiologically versatile member of the Crenarchaeota. PLoS One 6: e24222
2011Co-Authors: Bettina Siebers, Melanie Zaparty, Britta Tjaden, Guenter Raddatz, Sonja-verena Albers, Fabian Blombach, Arnulf Kletzin, Nikos C. Kyrpides, Steve D, Christa LanzAbstract:Here, we report on the complete genome sequence of the hyperthermophilic Crenarchaeum Thermoproteus tenax (strain Kra1, DSM 2078T) a type strain of the crenarchaeotal order Thermoproteales. Its circular 1.84-megabase genome harbors no extrachromosomal elements and 2,051 open reading frames are identified, covering 90.6 % of the complete sequence, which represents a high coding density. Derived from the gene content, T. tenax is a representative member of the Crenarchaeota. The organism is strictly anaerobic and sulfur-dependent with optimal growth at 86uC and pH 5.6. On
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crystal structure and stereochemical studies of kd p g aldolase from Thermoproteus tenax
Proteins, 2008Co-Authors: Anuschka Pauluhn, Hatim Ahmed, Bettina Siebers, Esben Lorentzen, Sebastian Buchinger, Dietmar Schomburg, Ehmke PohlAbstract:Carbon-carbon bond forming enzymes offer great potential for organic biosynthesis. Hence there is an ongoing effort to improve their biocatalytic properties, regarding availability, activity, stability, and substrate specificity and selectivity. Aldolases belong to the class of C-C bond forming enzymes and play important roles in numerous cellular processes. In several hyperthermophilic Archaea the 2-keto-3-deoxy-(6-phospho)-gluconate (KD(P)G) aldolase was identified as a key player in the metabolic pathway. The carbohydrate metabolism of the hyperthermophilic Crenarchaeote Thermoproteus tenax, for example, has been found to employ a combination of a variant of the Embden-Meyerhof-Parnas pathway and an unusual branched Entner-Doudoroff pathway that harbors a nonphosphorylative and a semiphosphorylative branch. The KD(P)G aldolase catalyzes the reversible cleavage of 2-keto-3-deoxy-6-phosphogluconate (KDPG) and 2-keto-3-deoxygluconate (KDG) forming pyruvate and glyceraldehyde 3-phosphate or glyceraldehyde, respectively. In T. tenax initial studies revealed that the pathway is specific for glucose, whereas in the thermoacidophilic Crenarchaeote Sulfolobus solfataricus the pathway was shown to be promiscuous for glucose and galactose degradation. The KD(P)G aldolase of S. solfataricus lacks stereo control and displays additional activity with 2-keto-3-deoxy-6-phosphogalactonate (KDPGal) and 2-keto-3-deoxygalactonate (KDGal), similar to the KD(P)G aldolase of Sulfolobus acidocaldarius. To address the stereo control of the T. tenax enzyme the formation of the two C4 epimers KDG and KDGal was analyzed via gas chromatography combined with mass spectroscopy. Furthermore, the crystal structure of the apoprotein was determined to a resolution of 2.0 A, and the crystal structure of the protein covalently linked to a pathway intermediate, namely pyruvate, was determined to 2.2 A. Interestingly, although the pathway seems to be specific for glucose in T. tenax the enzyme apparently also lacks stereo control, suggesting that the enzyme is a trade-off between required catabolic flexibility needed for the conversion of phosphorylated and nonphosphorylated substrates and required stereo control of cellular/physiological enzymatic reactions.
Nina A. Brunner - One of the best experts on this subject based on the ideXlab platform.
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the crystal structure of the allosteric non phosphorylating glyceraldehyde 3 phosphate dehydrogenase from the hyperthermophilic archaeum Thermoproteus tenax
Journal of Biological Chemistry, 2002Co-Authors: Ehmke Pohl, Nina A. Brunner, Matthias Wilmanns, Reinhard HenselAbstract:Abstract The NAD+-dependent non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase (GAPN) from the hyperthermophilic archaeum Thermoproteus tenaxrepresents an archaeal member of the diverse superfamily of aldehyde dehydrogenases (ALDHs). GAPN catalyzes the irreversible oxidation ofd-glyceraldehyde 3-phosphate to 3-phosphoglycerate. In this study, we present the crystal structure of GAPN in complex with its natural inhibitor NADP+ determined by multiple anomalous diffraction methods. The structure was refined to a resolution of 2.4 A with an R-factor of 0.21. The overall fold of GAPN is similar to the structures of ALDHs described previously, consisting of three domains: a nucleotide-binding domain, a catalytic domain, and an oligomerization domain. Local differences in the active site are responsible for substrate specificity. The inhibitor NADP+binds at an equivalent site to the cosubstrate-binding site of other ALDHs and blocks the enzyme in its inactive state, possibly preventing the transition to the active conformation. Structural comparison between GAPN from the hyperthermophilic T. tenax and homologs of mesophilic organisms establishes several characteristics of thermostabilization. These include protection against heat-induced covalent modifications by reducing and stabilizing labile residues, a decrease in number and volume of empty cavities, an increase in β-strand content, and a strengthening of subunit contacts by ionic and hydrophobic interactions.
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nonphosphorylating glyceraldehyde 3 phosphate dehydrogenase from Thermoproteus tenax
Methods in Enzymology, 2001Co-Authors: Nina A. Brunner, Reinhard HenselAbstract:Publisher Summary Nonphosphorylating glyceraldehyde-3-phosphate dehydrogenases (GAPN) catalyze the irreversible oxidation of o-glyceraldehyde 3-phosphate (GAP) to 3-phosphoglycerate (3-PG) by reduction of NAD(P)+ to NAD(P)H. Despite the fact that GAPN shares a similar catalytic mechanism with phosphorylating GAPDH, their reaction is unidirectional and independent of inorganic phosphate, implying that no energy conservation takes place. Although in Bacteria and Eucarya, GAPN are widely distributed and well characterized, GAPN of the hyperthermophilic archaeon Thermoproteus tenax represents the first identified homolog within the archaeal domain and the only enzyme biochemically characterized so far. NAD+-dependent GAPN of T. tenax has been identified as an integral constituent of the catabolic Embden-Meyerhof-Parnas (EMP) pathway. Like other GAPN, the archaeal enzyme is inhibited allosterically by several metabolic compounds containing phosphate moieties. In addition, the enzyme of T. tenax is activated by a broad spectrum of effectors, including various intermediates of sugar and energy metabolism, adenosine phosphates and nicotinamide adenine dinucleotides. Because of its high allosteric potential and the irreversible mode of catalysis, the enzyme is considered to be the main control point of glycolysis, governing the carbon flux through the pathway in response to growth conditions.
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crystallization and preliminary x ray diffraction analysis of the nad dependent non phosphorylating gapdh of the hyperthermophilic archaeon Thermoproteus tenax
Acta Crystallographica Section D-biological Crystallography, 2000Co-Authors: Nina A. Brunner, Dietmar Lang, Matthias Wilmanns, Reinhard HenselAbstract:Recombinant non-phosphorylating NAD+-dependent glyceraldehyde-3-phosphate dehydrogenase (GAPN) of the hyperthermophilic crenarchaeote Thermoproteus tenax has been overexpressed, purified and crystallized using the hanging-drop vapour-diffusion technique. Crystals of different habits were obtained from several precipitant solutions (salts and polyethylene glycols). Preliminary X-ray analysis was performed with crystals grown in ammonium formate, which belonged to the primitive hexagonal space group P622, and had unit-cell parameters a = b = 184.8, c = 133.0 A, γ = 120°. Assuming a molecular weight of 55 kDa, a Matthews parameter of 3.3 A3 Da−1 is calculated assuming two molecules per asymmetric unit. The diffraction limit of these crystals is 2.5 A resolution.
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Correspondence e-mail:
1999Co-Authors: Nina A. Brunner, Dietmar A A, Matthias B Wilmannsb, Reinhard HenselaAbstract:Crystallization and preliminary X-ray diffraction analysis of the NAD-dependent non-phosphorylating GAPDH of the hyperthermophilic archaeon Thermoproteus tena
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NAD+-dependent glyceraldehyde-3-phosphate dehydrogenase from Thermoproteus tenax. The first identified archaeal member of the aldehyde dehydrogenase superfamily is a glycolytic enzyme with unusual regulatory properties
Journal of Biological Chemistry, 1998Co-Authors: Nina A. Brunner, Bettina Siebers, Henner Brinkmann, Reinhard HenselAbstract:The hyperthermophilic archaeum Thermoproteus tenax possesses two glyceraldehyde-3-phosphate dehydrogenases differing in cosubstrate specificity and phosphate dependence of the catalyzed reaction. NAD+-dependent glyceraldehyde-3-phosphate dehydrogenase catalyzes the phosphate-independent irreversible oxidation of D-glyceraldehyde 3-phosphate to 3-phosphoglycerate. The coding gene was cloned, sequenced, and expressed in Escherichia coli. Sequence comparisons showed no similarity to phosphorylating glyceraldehyde-3-phosphate dehydrogenases but revealed a relationship to aldehyde dehydrogenases, with the highest similarity to the subgroup of nonphosphorylating glyceraldehyde-3-phosphate dehydrogenases. The activity of the enzyme is affected by a series of metabolites. All effectors tested influence the affinity of the enzyme for its cosubstrate NAD+. Whereas NADP(H), NADH, and ATP reduce the affinity for the cosubstrate, AMP, ADP, glucose 1-phosphate, and fructose 6-phosphate increase the affinity for NAD+. Additionally, most of the effectors investigated induce cooperativity of NAD+ binding. The irreversible catabolic oxidation of glyceraldehyde 3-phosphate, the control of the enzyme by energy charge of the cell, and the regulation by intermediates of glycolysis and glucan degradation identify the NAD+-dependent glyceraldehyde-3-phosphate dehydrogenase as an integral constituent of glycolysis in T. tenax. Its regulatory properties substitute for those lacking in the reversible nonregulated pyrophosphate-dependent phosphofructokinase in this variant of the Embden-Meyerhof-Parnas pathway.
Britta Tjaden - One of the best experts on this subject based on the ideXlab platform.
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characterization of the crispr cas subtype i a system of the hyperthermophilic crenarchaeon Thermoproteus tenax
Journal of Bacteriology, 2012Co-Authors: Andre Plagens, Britta Tjaden, Anna Hagemann, Lennart Randau, Reinhard HenselAbstract:ABSTRACT CRISPR (clustered regularly interspaced short palindromic repeats) elements and cas (CRISPR-associated) genes are widespread in Bacteria and Archaea. The CRISPR/Cas system operates as a defense mechanism against mobile genetic elements (i.e., viruses or plasmids). Here, we investigate seven CRISPR loci in the genome of the crenarchaeon Thermoproteus tenax that include spacers with significant similarity not only to archaeal viruses but also to T. tenax genes. The analysis of CRISPR RNA (crRNA) transcription reveals transcripts of a length between 50 and 130 nucleotides, demonstrating the processing of larger crRNA precursors. The organization of identified cas genes resembles CRISPR/Cas subtype I-A, and the core cas genes are shown to be arranged on two polycistronic transcripts: cascis (cas4, cas1/2, and csa1) and cascade (csa5, cas7, cas5a, cas3, cas3′, and cas8a2). Changes in the environmental parameters such as UV-light exposure or high ionic strength modulate cas gene transcription. Two reconstitution protocols were established for the production of two discrete multipartite Cas protein complexes that correspond to their operonic gene arrangement. These data provide insights into the specialized mechanisms of an archaeal CRISPR/Cas system and allow selective functional analyses of Cas protein complexes in the future.
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The Complete Genome Sequence of Thermoproteus tenax: A Physiologically Versatile Member of the Crenarchaeota
PloS one, 2011Co-Authors: Bettina Siebers, Melanie Zaparty, Britta Tjaden, Guenter Raddatz, Sonja-verena Albers, Steve D Bell, Fabian Blombach, Arnulf Kletzin, Nikos C. Kyrpides, Christa LanzAbstract:Here, we report on the complete genome sequence of the hyperthermophilic Crenarchaeum Thermoproteus tenax (strain Kra1, DSM 2078T) a type strain of the crenarchaeotal order Thermoproteales. Its circular 1.84-megabase genome harbors no extrachromosomal elements and 2,051 open reading frames are identified, covering 90.6% of the complete sequence, which represents a high coding density. Derived from the gene content, T. tenax is a representative member of the Crenarchaeota. The organism is strictly anaerobic and sulfur-dependent with optimal growth at 86°C and pH 5.6. One particular feature is the great metabolic versatility, which is not accompanied by a distinct increase of genome size or information density as compared to other Crenarchaeota. T. tenax is able to grow chemolithoautotrophically (CO2/H2) as well as chemoorganoheterotrophically in presence of various organic substrates. All pathways for synthesizing the 20 proteinogenic amino acids are present. In addition, two presumably complete gene sets for NADH:quinone oxidoreductase (complex I) were identified in the genome and there is evidence that either NADH or reduced ferredoxin might serve as electron donor. Beside the typical archaeal A0A1-ATP synthase, a membrane-bound pyrophosphatase is found, which might contribute to energy conservation. Surprisingly, all genes required for dissimilatory sulfate reduction are present, which is confirmed by growth experiments. Mentionable is furthermore, the presence of two proteins (ParA family ATPase, actin-like protein) that might be involved in cell division in Thermoproteales, where the ESCRT system is absent, and of genes involved in genetic competence (DprA, ComF) that is so far unique within Archaea.
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The complete genome sequence of Thermoproteus tenax: a physiologically versatile member of the Crenarchaeota. PLoS One 6: e24222
2011Co-Authors: Bettina Siebers, Melanie Zaparty, Britta Tjaden, Guenter Raddatz, Sonja-verena Albers, Fabian Blombach, Arnulf Kletzin, Nikos C. Kyrpides, Steve D, Christa LanzAbstract:Here, we report on the complete genome sequence of the hyperthermophilic Crenarchaeum Thermoproteus tenax (strain Kra1, DSM 2078T) a type strain of the crenarchaeotal order Thermoproteales. Its circular 1.84-megabase genome harbors no extrachromosomal elements and 2,051 open reading frames are identified, covering 90.6 % of the complete sequence, which represents a high coding density. Derived from the gene content, T. tenax is a representative member of the Crenarchaeota. The organism is strictly anaerobic and sulfur-dependent with optimal growth at 86uC and pH 5.6. On
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The central carbohydrate metabolism of the hyperthermophilic crenarchaeote Thermoproteus tenax: Pathways and insights into their regulation
Archives of Microbiology, 2008Co-Authors: Melanie Zaparty, Britta Tjaden, Reinhard Hensel, Bettina SiebersAbstract:Although the complexity and modifications of the archaeal central carbohydrate metabolism (CCM) are well established, the knowledge about its regulation is rather limited. The facultatively heterotrophic, hyperthermophilic crenarchaeote Thermoproteus tenax utilizes a modified version of the reversible Embden-Meyerhof-Parnas (EMP) and the catabolic, branched Entner-Doudoroff (ED) pathway for glucose metabolism. Glucose is completely oxidized to carbon dioxide via the oxidative tricarboxylic acid (TCA) cycle, which is supposedly used in the reductive direction for carbon dioxide fixation under autotrophic growth conditions. Elemental sulfur is used as final electron acceptor. The CCM of T. tenax has been well studied on protein level as well as on gene level by performing a focused transcriptional analysis (CCM DNA microarray). In contrast to the classical pathways found in Bacteria and Eucarya allosteric regulation seems to play a minor role, therefore emphasizing the important role of regulation on transcript level in T. tenax. Whereas the EMP pathway and the TCA cycle show a highly coordinated regulation on gene level, the catabolic, branched ED pathway reveals no strong regulation. The CCM pathways in T. tenax and the current understanding of their regulation are presented.
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embden meyerhof parnas and entner doudoroff pathways in Thermoproteus tenax metabolic parallelism or specific adaptation
Biochemical Society Transactions, 2004Co-Authors: Hatim Ahmed, Britta Tjaden, Reinhard Hensel, Bettina SiebersAbstract:Genome data as well as biochemical studies have indicated that – as a peculiarity within hyperthermophilic Archaea – Thermoproteus tenax uses three different pathways for glucose metabolism, a variant of the reversible EMP (Embden–Meyerhof–Parnas) pathway and two different modifications of the ED (Entner–Doudoroff) pathway, a non-phosphorylative and a semi-phosphorylative version. An overview of the three different pathways is presented and the physiological function of the variants is discussed.
Melanie Zaparty - One of the best experts on this subject based on the ideXlab platform.
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Running title: Thermoproteus tenax focused transcriptional analysis
2013Co-Authors: Thermoproteus Tenax, Melanie Zaparty, Reinhard Hensel, Er Zaigler, Claudia Stamme, Bettina SiebersAbstract:In order to unravel the role of regulation on transcript level in the central carbohydrate metabolism (CCM) of Thermoproteus tenax, a focused DNA microarray was constructed by using 85 open reading frames involved in the CCM. Transcriptional analysis was performed comparing heterotrophic growth on glucose versus autotrophic growth on CO2/H2. The anaerobic, facultative heterotrophic crenarchaeum Thermoproteus tenax shows a sulfur-dependent energy metabolism and grows optimally at 86°C and pH 5.6. In addition to autotrophic growth on carbon dioxide and hydrogen (CO2/H2), heterotrophic growth was reported on various carbohydrates such as starch, glycogen or glucose (40). The combination of genomics-based and biochemical approaches revealed that T. tenax is the only archaeum currently known that uses two different pathways for carbohydrate catabolism in parallel: A reversible Embden-Meyerhof-Parnas (EMP) pathway and the catabolic, so-called branched Entner-Doudoroff (ED) pathway
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the first prokaryotic trehalose synthase complex identified in the hyperthermophilic crenarchaeon Thermoproteus tenax
PLOS ONE, 2013Co-Authors: Melanie Zaparty, Reinhard Hensel, Henner Brinkmann, Anna Hagemann, Christopher Brasen, Andrei N Lupas, Bettina SiebersAbstract:The role of the disaccharide trehalose, its biosynthesis pathways and their regulation in Archaea are still ambiguous. In Thermoproteus tenax a fused trehalose-6-phosphate synthase/phosphatase (TPSP), consisting of an N-terminal trehalose-6-phosphate synthase (TPS) and a C-terminal trehalose-6-phosphate phosphatase (TPP) domain, was identified. The tpsp gene is organized in an operon with a putative glycosyltransferase (GT) and a putative mechanosensitive channel (MSC). The T. tenax TPSP exhibits high phosphatase activity, but requires activation by the co-expressed GT for bifunctional synthase-phosphatase activity. The GT mediated activation of TPS activity relies on the fusion of both, TPS and TPP domain, in the TPSP enzyme. Activation is mediated by complex-formation in vivo as indicated by yeast two-hybrid and crude extract analysis. In combination with first evidence for MSC activity the results suggest a sophisticated stress response involving TPSP, GT and MSC in T. tenax and probably in other Thermoproteales species. The monophyletic prokaryotic TPSP proteins likely originated via a single fusion event in the Bacteroidetes with subsequent horizontal gene transfers to other Bacteria and Archaea. Furthermore, evidence for the origin of eukaryotic TPSP fusions via HGT from prokaryotes and therefore a monophyletic origin of eukaryotic and prokaryotic fused TPSPs is presented. This is the first report of a prokaryotic, archaeal trehalose synthase complex exhibiting a much more simple composition than the eukaryotic complex described in yeast. Thus, complex formation and a complex-associated regulatory potential might represent a more general feature of trehalose synthesizing proteins.
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The Complete Genome Sequence of Thermoproteus tenax: A Physiologically Versatile Member of the Crenarchaeota
PloS one, 2011Co-Authors: Bettina Siebers, Melanie Zaparty, Britta Tjaden, Guenter Raddatz, Sonja-verena Albers, Steve D Bell, Fabian Blombach, Arnulf Kletzin, Nikos C. Kyrpides, Christa LanzAbstract:Here, we report on the complete genome sequence of the hyperthermophilic Crenarchaeum Thermoproteus tenax (strain Kra1, DSM 2078T) a type strain of the crenarchaeotal order Thermoproteales. Its circular 1.84-megabase genome harbors no extrachromosomal elements and 2,051 open reading frames are identified, covering 90.6% of the complete sequence, which represents a high coding density. Derived from the gene content, T. tenax is a representative member of the Crenarchaeota. The organism is strictly anaerobic and sulfur-dependent with optimal growth at 86°C and pH 5.6. One particular feature is the great metabolic versatility, which is not accompanied by a distinct increase of genome size or information density as compared to other Crenarchaeota. T. tenax is able to grow chemolithoautotrophically (CO2/H2) as well as chemoorganoheterotrophically in presence of various organic substrates. All pathways for synthesizing the 20 proteinogenic amino acids are present. In addition, two presumably complete gene sets for NADH:quinone oxidoreductase (complex I) were identified in the genome and there is evidence that either NADH or reduced ferredoxin might serve as electron donor. Beside the typical archaeal A0A1-ATP synthase, a membrane-bound pyrophosphatase is found, which might contribute to energy conservation. Surprisingly, all genes required for dissimilatory sulfate reduction are present, which is confirmed by growth experiments. Mentionable is furthermore, the presence of two proteins (ParA family ATPase, actin-like protein) that might be involved in cell division in Thermoproteales, where the ESCRT system is absent, and of genes involved in genetic competence (DprA, ComF) that is so far unique within Archaea.
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The complete genome sequence of Thermoproteus tenax: a physiologically versatile member of the Crenarchaeota. PLoS One 6: e24222
2011Co-Authors: Bettina Siebers, Melanie Zaparty, Britta Tjaden, Guenter Raddatz, Sonja-verena Albers, Fabian Blombach, Arnulf Kletzin, Nikos C. Kyrpides, Steve D, Christa LanzAbstract:Here, we report on the complete genome sequence of the hyperthermophilic Crenarchaeum Thermoproteus tenax (strain Kra1, DSM 2078T) a type strain of the crenarchaeotal order Thermoproteales. Its circular 1.84-megabase genome harbors no extrachromosomal elements and 2,051 open reading frames are identified, covering 90.6 % of the complete sequence, which represents a high coding density. Derived from the gene content, T. tenax is a representative member of the Crenarchaeota. The organism is strictly anaerobic and sulfur-dependent with optimal growth at 86uC and pH 5.6. On
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a novel trehalose synthesizing pathway in the hyperthermophilic crenarchaeon Thermoproteus tenax the unidirectional tret pathway
Archives of Microbiology, 2008Co-Authors: Theresa Kouril, Melanie Zaparty, Henner Brinkmann, Jeannette Marrero, Bettina SiebersAbstract:In the genome of the hyperthermophilic archaeon Thermoproteus tenax a gene (treS/P) encoding a protein with similarity to annotated trehalose phosphorylase (TreP), trehalose synthase (TreS) and more recently characterized trehalose glycosyltransferring synthase (TreT) was identified. The treS/P gene as well as an upstream located ORF of unknown function (orfY) were cloned, heterologously expressed in E. coli and purified. The enzymatic characterization of the putative TreS/P revealed TreT activity. However, contrary to the previously characterized reversible TreT from Thermococcus litoralis and Pyrococcus horikoshii, the T. tenax enzyme is unidirectional and catalyzes only the formation of trehalose from UDP (ADP)-glucose and glucose. The T. tenax enzyme differs from the reversible TreT of T. litoralis by its preference for UDP-glucose as co-substrate. Phylogenetic and comparative gene context analyses reveal a conserved organization of the unidirectional TreT and OrfY gene cluster that is present in many Archaea and a few Bacteria. In contrast, the reversible TreT pathway seems to be restricted to only a few archaeal (e.g. Thermococcales) and bacterial (Thermotogales) members. Here we present a new pathway exclusively involved in trehalose synthesis--the unidirectional TreT pathway--and discuss its physiological role as well as its phylogenetic distribution.
