The Experts below are selected from a list of 147 Experts worldwide ranked by ideXlab platform
Stefan M. Sievert - One of the best experts on this subject based on the ideXlab platform.
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Evidence for Autotrophic CO2 Fixation via the Reductive Tricarboxylic Acid Cycle by Members of the ε Subdivision of Proteobacteria
Journal of bacteriology, 2005Co-Authors: Michael Hügler, Carl O. Wirsen, Georg Fuchs, Craig D. Taylor, Stefan M. SievertAbstract:Based on 16S rRNA gene surveys, bacteria of the e subdivision of proteobacteria have been identified to be important members of microbial communities in a variety of environments, and quite a few have been demonstrated to grow autotrophically. However, no information exists on what pathway of autotrophic carbon fixation these bacteria might use. In this study, Thiomicrospira denitrificans and Candidatus Arcobacter sulfidicus, two chemolithoautotrophic sulfur oxidizers of the e subdivision of proteobacteria, were examined for activities of the key enzymes of the known autotrophic CO 2 fixation pathways. Both organisms contained activities of the key enzymes of the reductive Tricarboxylic Acid cycle, ATP citrate lyase, 2-oxoglutarate:ferredoxin oxidoreductase, and pyruvate:ferredoxin oxidoreductase. Furthermore, no activities of key enzymes of other CO 2 fixation pathways, such as the Calvin cycle, the reductive acetyl coenzyme A pathway, and the 3-hydroxypropionate cycle, could be detected. In addition to the key enzymes, the activities of the other enzymes involved in the reductive Tricarboxylic Acid cycle could be measured. Sections of the genes encoding the α- and β-subunits of ATP citrate lyase could be amplified from both organisms. These findings represent the first direct evidence for the operation of the reductive Tricarboxylic Acid cycle for autotrophic CO 2 fixation in e-proteobacteria. Since e-proteobacteria closely related to these two organisms are important in many habitats, such as hydrothermal vents, oxic-sulfidic interfaces, or oilfields, these results suggest that autotrophic CO 2 fixation via the reductive Tricarboxylic Acid cycle might be more important than previously considered.
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evidence for autotrophic co2 fixation via the reductive Tricarboxylic Acid cycle by members of the e subdivision of proteobacteria
Journal of Bacteriology, 2005Co-Authors: Michael Hügler, Carl O. Wirsen, Georg Fuchs, Craig D. Taylor, Stefan M. SievertAbstract:Based on 16S rRNA gene surveys, bacteria of the e subdivision of proteobacteria have been identified to be important members of microbial communities in a variety of environments, and quite a few have been demonstrated to grow autotrophically. However, no information exists on what pathway of autotrophic carbon fixation these bacteria might use. In this study, Thiomicrospira denitrificans and Candidatus Arcobacter sulfidicus, two chemolithoautotrophic sulfur oxidizers of the e subdivision of proteobacteria, were examined for activities of the key enzymes of the known autotrophic CO 2 fixation pathways. Both organisms contained activities of the key enzymes of the reductive Tricarboxylic Acid cycle, ATP citrate lyase, 2-oxoglutarate:ferredoxin oxidoreductase, and pyruvate:ferredoxin oxidoreductase. Furthermore, no activities of key enzymes of other CO 2 fixation pathways, such as the Calvin cycle, the reductive acetyl coenzyme A pathway, and the 3-hydroxypropionate cycle, could be detected. In addition to the key enzymes, the activities of the other enzymes involved in the reductive Tricarboxylic Acid cycle could be measured. Sections of the genes encoding the α- and β-subunits of ATP citrate lyase could be amplified from both organisms. These findings represent the first direct evidence for the operation of the reductive Tricarboxylic Acid cycle for autotrophic CO 2 fixation in e-proteobacteria. Since e-proteobacteria closely related to these two organisms are important in many habitats, such as hydrothermal vents, oxic-sulfidic interfaces, or oilfields, these results suggest that autotrophic CO 2 fixation via the reductive Tricarboxylic Acid cycle might be more important than previously considered.
Michael Hügler - One of the best experts on this subject based on the ideXlab platform.
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Evidence for Autotrophic CO2 Fixation via the Reductive Tricarboxylic Acid Cycle by Members of the ε Subdivision of Proteobacteria
Journal of bacteriology, 2005Co-Authors: Michael Hügler, Carl O. Wirsen, Georg Fuchs, Craig D. Taylor, Stefan M. SievertAbstract:Based on 16S rRNA gene surveys, bacteria of the e subdivision of proteobacteria have been identified to be important members of microbial communities in a variety of environments, and quite a few have been demonstrated to grow autotrophically. However, no information exists on what pathway of autotrophic carbon fixation these bacteria might use. In this study, Thiomicrospira denitrificans and Candidatus Arcobacter sulfidicus, two chemolithoautotrophic sulfur oxidizers of the e subdivision of proteobacteria, were examined for activities of the key enzymes of the known autotrophic CO 2 fixation pathways. Both organisms contained activities of the key enzymes of the reductive Tricarboxylic Acid cycle, ATP citrate lyase, 2-oxoglutarate:ferredoxin oxidoreductase, and pyruvate:ferredoxin oxidoreductase. Furthermore, no activities of key enzymes of other CO 2 fixation pathways, such as the Calvin cycle, the reductive acetyl coenzyme A pathway, and the 3-hydroxypropionate cycle, could be detected. In addition to the key enzymes, the activities of the other enzymes involved in the reductive Tricarboxylic Acid cycle could be measured. Sections of the genes encoding the α- and β-subunits of ATP citrate lyase could be amplified from both organisms. These findings represent the first direct evidence for the operation of the reductive Tricarboxylic Acid cycle for autotrophic CO 2 fixation in e-proteobacteria. Since e-proteobacteria closely related to these two organisms are important in many habitats, such as hydrothermal vents, oxic-sulfidic interfaces, or oilfields, these results suggest that autotrophic CO 2 fixation via the reductive Tricarboxylic Acid cycle might be more important than previously considered.
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evidence for autotrophic co2 fixation via the reductive Tricarboxylic Acid cycle by members of the e subdivision of proteobacteria
Journal of Bacteriology, 2005Co-Authors: Michael Hügler, Carl O. Wirsen, Georg Fuchs, Craig D. Taylor, Stefan M. SievertAbstract:Based on 16S rRNA gene surveys, bacteria of the e subdivision of proteobacteria have been identified to be important members of microbial communities in a variety of environments, and quite a few have been demonstrated to grow autotrophically. However, no information exists on what pathway of autotrophic carbon fixation these bacteria might use. In this study, Thiomicrospira denitrificans and Candidatus Arcobacter sulfidicus, two chemolithoautotrophic sulfur oxidizers of the e subdivision of proteobacteria, were examined for activities of the key enzymes of the known autotrophic CO 2 fixation pathways. Both organisms contained activities of the key enzymes of the reductive Tricarboxylic Acid cycle, ATP citrate lyase, 2-oxoglutarate:ferredoxin oxidoreductase, and pyruvate:ferredoxin oxidoreductase. Furthermore, no activities of key enzymes of other CO 2 fixation pathways, such as the Calvin cycle, the reductive acetyl coenzyme A pathway, and the 3-hydroxypropionate cycle, could be detected. In addition to the key enzymes, the activities of the other enzymes involved in the reductive Tricarboxylic Acid cycle could be measured. Sections of the genes encoding the α- and β-subunits of ATP citrate lyase could be amplified from both organisms. These findings represent the first direct evidence for the operation of the reductive Tricarboxylic Acid cycle for autotrophic CO 2 fixation in e-proteobacteria. Since e-proteobacteria closely related to these two organisms are important in many habitats, such as hydrothermal vents, oxic-sulfidic interfaces, or oilfields, these results suggest that autotrophic CO 2 fixation via the reductive Tricarboxylic Acid cycle might be more important than previously considered.
Paul A. Srere - One of the best experts on this subject based on the ideXlab platform.
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Reversible transdominant inhibition of a metabolic pathway. In vivo evidence of interaction between two sequential Tricarboxylic Acid cycle enzymes in yeast.
The Journal of biological chemistry, 2000Co-Authors: Christian Vélot, Paul A. SrereAbstract:The enzymes of the Krebs Tricarboxylic Acid cycle in mitochondria are proposed to form a supramolecular complex, in which there is channeling of intermediates between enzyme active sites. While interactions have been demonstrated in vitro between most of the sequential Tricarboxylic Acid cycle enzymes, no direct evidence has been obtained in vivo for such interactions. We have isolated, in the Saccharomyces cerevisiae gene encoding the Tricarboxylic Acid cycle enzyme citrate synthase Cit1p, an "assembly mutation," i.e. a mutation that causes a Tricarboxylic Acid cycle deficiency without affecting the citrate synthase activity. We have shown that a 15-amino Acid peptide from wild type Cit1p encompassing the mutation point inhibits the Tricarboxylic Acid cycle in a dominant manner, and that the inhibitory phenotype is overcome by a co-overexpression of Mdh1p, the mitochondrial malate dehydrogenase. These data provide the first direct in vivo evidence of interaction between two sequential Tricarboxylic Acid cycle enzymes, Cit1p and Mdh1p, and indicate that the characterization of assembly mutations by the reversible transdominant inhibition method may be a powerful way to study multienzyme complexes in their physiological context.
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Is there tight channelling in the Tricarboxylic Acid cycle metabolon
Biochemical Society transactions, 1991Co-Authors: Balazs Sumegi, A D Sherry, Craig R. Malloy, C. Evans, Paul A. SrereAbstract:Is there tight channelling in the Tricarboxylic Acid cycle metabolon? Balazs Sumegi,§ A. Dean Sherry,§ Craig R. Malloy,*$ Claudia Evans*t and Paul A. Srere*t *Pre-Clinical Science Unit of the Department of Veterans Affairs Medical Center, tDepartment of Biochemistry and $The Mary Nell & Ralph B. Rogers N.M.R. Center, The University of Texas Southwestern Medical Center at Dallas, 4500 South Lancaster Road, Dallas, TX 752 16, U.S.A. and §Chemistry Department, The University of Texas at Dallas, Richardson, TX 75083-0688, U.S.A.
Carl O. Wirsen - One of the best experts on this subject based on the ideXlab platform.
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Evidence for Autotrophic CO2 Fixation via the Reductive Tricarboxylic Acid Cycle by Members of the ε Subdivision of Proteobacteria
Journal of bacteriology, 2005Co-Authors: Michael Hügler, Carl O. Wirsen, Georg Fuchs, Craig D. Taylor, Stefan M. SievertAbstract:Based on 16S rRNA gene surveys, bacteria of the e subdivision of proteobacteria have been identified to be important members of microbial communities in a variety of environments, and quite a few have been demonstrated to grow autotrophically. However, no information exists on what pathway of autotrophic carbon fixation these bacteria might use. In this study, Thiomicrospira denitrificans and Candidatus Arcobacter sulfidicus, two chemolithoautotrophic sulfur oxidizers of the e subdivision of proteobacteria, were examined for activities of the key enzymes of the known autotrophic CO 2 fixation pathways. Both organisms contained activities of the key enzymes of the reductive Tricarboxylic Acid cycle, ATP citrate lyase, 2-oxoglutarate:ferredoxin oxidoreductase, and pyruvate:ferredoxin oxidoreductase. Furthermore, no activities of key enzymes of other CO 2 fixation pathways, such as the Calvin cycle, the reductive acetyl coenzyme A pathway, and the 3-hydroxypropionate cycle, could be detected. In addition to the key enzymes, the activities of the other enzymes involved in the reductive Tricarboxylic Acid cycle could be measured. Sections of the genes encoding the α- and β-subunits of ATP citrate lyase could be amplified from both organisms. These findings represent the first direct evidence for the operation of the reductive Tricarboxylic Acid cycle for autotrophic CO 2 fixation in e-proteobacteria. Since e-proteobacteria closely related to these two organisms are important in many habitats, such as hydrothermal vents, oxic-sulfidic interfaces, or oilfields, these results suggest that autotrophic CO 2 fixation via the reductive Tricarboxylic Acid cycle might be more important than previously considered.
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evidence for autotrophic co2 fixation via the reductive Tricarboxylic Acid cycle by members of the e subdivision of proteobacteria
Journal of Bacteriology, 2005Co-Authors: Michael Hügler, Carl O. Wirsen, Georg Fuchs, Craig D. Taylor, Stefan M. SievertAbstract:Based on 16S rRNA gene surveys, bacteria of the e subdivision of proteobacteria have been identified to be important members of microbial communities in a variety of environments, and quite a few have been demonstrated to grow autotrophically. However, no information exists on what pathway of autotrophic carbon fixation these bacteria might use. In this study, Thiomicrospira denitrificans and Candidatus Arcobacter sulfidicus, two chemolithoautotrophic sulfur oxidizers of the e subdivision of proteobacteria, were examined for activities of the key enzymes of the known autotrophic CO 2 fixation pathways. Both organisms contained activities of the key enzymes of the reductive Tricarboxylic Acid cycle, ATP citrate lyase, 2-oxoglutarate:ferredoxin oxidoreductase, and pyruvate:ferredoxin oxidoreductase. Furthermore, no activities of key enzymes of other CO 2 fixation pathways, such as the Calvin cycle, the reductive acetyl coenzyme A pathway, and the 3-hydroxypropionate cycle, could be detected. In addition to the key enzymes, the activities of the other enzymes involved in the reductive Tricarboxylic Acid cycle could be measured. Sections of the genes encoding the α- and β-subunits of ATP citrate lyase could be amplified from both organisms. These findings represent the first direct evidence for the operation of the reductive Tricarboxylic Acid cycle for autotrophic CO 2 fixation in e-proteobacteria. Since e-proteobacteria closely related to these two organisms are important in many habitats, such as hydrothermal vents, oxic-sulfidic interfaces, or oilfields, these results suggest that autotrophic CO 2 fixation via the reductive Tricarboxylic Acid cycle might be more important than previously considered.
Georg Fuchs - One of the best experts on this subject based on the ideXlab platform.
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Evidence for Autotrophic CO2 Fixation via the Reductive Tricarboxylic Acid Cycle by Members of the ε Subdivision of Proteobacteria
Journal of bacteriology, 2005Co-Authors: Michael Hügler, Carl O. Wirsen, Georg Fuchs, Craig D. Taylor, Stefan M. SievertAbstract:Based on 16S rRNA gene surveys, bacteria of the e subdivision of proteobacteria have been identified to be important members of microbial communities in a variety of environments, and quite a few have been demonstrated to grow autotrophically. However, no information exists on what pathway of autotrophic carbon fixation these bacteria might use. In this study, Thiomicrospira denitrificans and Candidatus Arcobacter sulfidicus, two chemolithoautotrophic sulfur oxidizers of the e subdivision of proteobacteria, were examined for activities of the key enzymes of the known autotrophic CO 2 fixation pathways. Both organisms contained activities of the key enzymes of the reductive Tricarboxylic Acid cycle, ATP citrate lyase, 2-oxoglutarate:ferredoxin oxidoreductase, and pyruvate:ferredoxin oxidoreductase. Furthermore, no activities of key enzymes of other CO 2 fixation pathways, such as the Calvin cycle, the reductive acetyl coenzyme A pathway, and the 3-hydroxypropionate cycle, could be detected. In addition to the key enzymes, the activities of the other enzymes involved in the reductive Tricarboxylic Acid cycle could be measured. Sections of the genes encoding the α- and β-subunits of ATP citrate lyase could be amplified from both organisms. These findings represent the first direct evidence for the operation of the reductive Tricarboxylic Acid cycle for autotrophic CO 2 fixation in e-proteobacteria. Since e-proteobacteria closely related to these two organisms are important in many habitats, such as hydrothermal vents, oxic-sulfidic interfaces, or oilfields, these results suggest that autotrophic CO 2 fixation via the reductive Tricarboxylic Acid cycle might be more important than previously considered.
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evidence for autotrophic co2 fixation via the reductive Tricarboxylic Acid cycle by members of the e subdivision of proteobacteria
Journal of Bacteriology, 2005Co-Authors: Michael Hügler, Carl O. Wirsen, Georg Fuchs, Craig D. Taylor, Stefan M. SievertAbstract:Based on 16S rRNA gene surveys, bacteria of the e subdivision of proteobacteria have been identified to be important members of microbial communities in a variety of environments, and quite a few have been demonstrated to grow autotrophically. However, no information exists on what pathway of autotrophic carbon fixation these bacteria might use. In this study, Thiomicrospira denitrificans and Candidatus Arcobacter sulfidicus, two chemolithoautotrophic sulfur oxidizers of the e subdivision of proteobacteria, were examined for activities of the key enzymes of the known autotrophic CO 2 fixation pathways. Both organisms contained activities of the key enzymes of the reductive Tricarboxylic Acid cycle, ATP citrate lyase, 2-oxoglutarate:ferredoxin oxidoreductase, and pyruvate:ferredoxin oxidoreductase. Furthermore, no activities of key enzymes of other CO 2 fixation pathways, such as the Calvin cycle, the reductive acetyl coenzyme A pathway, and the 3-hydroxypropionate cycle, could be detected. In addition to the key enzymes, the activities of the other enzymes involved in the reductive Tricarboxylic Acid cycle could be measured. Sections of the genes encoding the α- and β-subunits of ATP citrate lyase could be amplified from both organisms. These findings represent the first direct evidence for the operation of the reductive Tricarboxylic Acid cycle for autotrophic CO 2 fixation in e-proteobacteria. Since e-proteobacteria closely related to these two organisms are important in many habitats, such as hydrothermal vents, oxic-sulfidic interfaces, or oilfields, these results suggest that autotrophic CO 2 fixation via the reductive Tricarboxylic Acid cycle might be more important than previously considered.
