The Experts below are selected from a list of 78 Experts worldwide ranked by ideXlab platform
John D Coates - One of the best experts on this subject based on the ideXlab platform.
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Anion transport as a target of adaption to perchlorate in Sulfate-reducing communities
The ISME Journal, 2020Co-Authors: Magdalena K Stoeva, Jennifer Kuehl, Alexey E. Kazakov, Ouwei Wang, Rowena Rushton-green, John D CoatesAbstract:Inhibitors can be used to control the functionality of microbial communities by targeting specific metabolisms. The targeted inhibition of dissimilatory Sulfate reduction limits the generation of toxic and corrosive hydrogen sulfide across several industrial systems. Sulfate-reducing microorganisms (SRM) are specifically inhibited by Sulfate analogs, such as perchlorate. Previously, we showed pure culture SRM adaptation to perchlorate stress through mutation of the Sulfate Adenylyltransferase, a central enzyme in the Sulfate reduction pathway. Here, we explored adaptation to perchlorate across unconstrained SRM on a community scale. We followed natural and bio-augmented sulfidogenic communities through serial transfers in increasing concentrations of perchlorate. Our results demonstrated that perchlorate stress altered community structure by initially selecting for innately more resistant strains. Isolation, whole-genome sequencing, and molecular biology techniques allowed us to define subsequent genetic mechanisms of adaptation that arose across the dominant adapting SRM. Changes in the regulation of divalent anion:sodium symporter family transporters led to increased intracellular Sulfate to perchlorate ratios, allowing SRM to escape the effects of competitive inhibition. Thus, in contrast to pure-culture results, SRM in communities cope with perchlorate stress via changes in anion transport and its regulation. This highlights the value of probing evolutionary questions in an ecological framework, bridging the gap between ecology, evolution, genomics, and physiology.
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adaptation of desulfovibrio alaskensis g20 to perchlorate a specific inhibitor of Sulfate reduction
Environmental Microbiology, 2019Co-Authors: Misha G Mehtakolte, Magdalena K Stoeva, Anchal Mehra, Steven A Redford, Matthew D Youngblut, Grant M Zane, Patrick Gregoire, Hans K Carlson, Judy D Wall, John D CoatesAbstract:Hydrogen sulfide produced by Sulfate-reducing microorganisms (SRM) poses significant health and economic risks, particularly during oil recovery. Previous studies identified perchlorate as a specific inhibitor of SRM. However, constant inhibitor addition to natural systems results in new selective pressures. Consequently, we investigated the ability of Desulfovibrio alaskensis G20 to evolve perchlorate resistance. Serial transfers in increasing concentrations of perchlorate led to robust growth in the presence of 100 mM inhibitor. Isolated adapted strains demonstrated a threefold increase in perchlorate resistance compared to the wild-type ancestor. Whole genome sequencing revealed a single base substitution in Dde_2265, the Sulfate Adenylyltransferase (sat). We purified and biochemically characterized the Sat from both wild-type and adapted strains, and showed that the adapted Sat was approximately threefold more resistant to perchlorate inhibition, mirroring whole cell results. The ability of this mutation to confer resistance across other inhibitors of sulfidogenesis was also assayed. The generalizability of this mutation was confirmed in multiple evolving G20 cultures and in another SRM, D. vulgaris Hildenborough. This work demonstrates that a single nucleotide polymorphism in Sat can have a significant impact on developing perchlorate resistance and emphasizes the value of adaptive laboratory evolution for understanding microbial responses to environmental perturbations.
Hans G. Trüper - One of the best experts on this subject based on the ideXlab platform.
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enzymology and molecular biology of Sulfate reduction in extremely thermophilic archaeon archaeoglobus fulgidus
Methods in Enzymology, 1994Co-Authors: Christiane Dahl, Norbert Speich, Hans G. TrüperAbstract:Publisher Summary This chapter describes enzymology and molecular biology of Sulfate reduction in Archaeoglobus fulgidus ( A. fulgidus ). A. fulgidus is an extreme thermophile and grows at temperatures between 64 and 92, with an optimum at 83. This organism carries out Sulfate reduction via the pathway originally proposed for bacterial species. Owing to its chemical inertia, Sulfate needs first to be activated to adenylylSulfate [adenosine-5′-phosphoSulfate (APS)] by ATP-sulfurylase [Sulfate Adenylyltransferase], with formation of pyrophosphate. The enzyme adenylylSulfate (APS) reductase catalyzes the reduction of APS to sulfite and AMP. Sulfite is finally reduced to sulfide by sulfite reductase. Auxiliary enzymes are widely applied in the determination of ATP sulfurylase and sulfite reductase activities from mesophilic organisms. ATP-sulfurylase from A. fulgidus is measured in the thermodynamically favored direction of ATP generation from the reaction of APS with pyrophosphate. The ATP formed is then spectrophotometrically determined. AdenylylSulfate reductase activity is measured in a continuous spectrophotometric assay in the direction of APS formation from sulfite and AMP with ferricyanide as electron acceptor.
Christiane Dahl - One of the best experts on this subject based on the ideXlab platform.
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enzymology and molecular biology of Sulfate reduction in extremely thermophilic archaeon archaeoglobus fulgidus
Methods in Enzymology, 1994Co-Authors: Christiane Dahl, Norbert Speich, Hans G. TrüperAbstract:Publisher Summary This chapter describes enzymology and molecular biology of Sulfate reduction in Archaeoglobus fulgidus ( A. fulgidus ). A. fulgidus is an extreme thermophile and grows at temperatures between 64 and 92, with an optimum at 83. This organism carries out Sulfate reduction via the pathway originally proposed for bacterial species. Owing to its chemical inertia, Sulfate needs first to be activated to adenylylSulfate [adenosine-5′-phosphoSulfate (APS)] by ATP-sulfurylase [Sulfate Adenylyltransferase], with formation of pyrophosphate. The enzyme adenylylSulfate (APS) reductase catalyzes the reduction of APS to sulfite and AMP. Sulfite is finally reduced to sulfide by sulfite reductase. Auxiliary enzymes are widely applied in the determination of ATP sulfurylase and sulfite reductase activities from mesophilic organisms. ATP-sulfurylase from A. fulgidus is measured in the thermodynamically favored direction of ATP generation from the reaction of APS with pyrophosphate. The ATP formed is then spectrophotometrically determined. AdenylylSulfate reductase activity is measured in a continuous spectrophotometric assay in the direction of APS formation from sulfite and AMP with ferricyanide as electron acceptor.
Magdalena K Stoeva - One of the best experts on this subject based on the ideXlab platform.
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Anion transport as a target of adaption to perchlorate in Sulfate-reducing communities
The ISME Journal, 2020Co-Authors: Magdalena K Stoeva, Jennifer Kuehl, Alexey E. Kazakov, Ouwei Wang, Rowena Rushton-green, John D CoatesAbstract:Inhibitors can be used to control the functionality of microbial communities by targeting specific metabolisms. The targeted inhibition of dissimilatory Sulfate reduction limits the generation of toxic and corrosive hydrogen sulfide across several industrial systems. Sulfate-reducing microorganisms (SRM) are specifically inhibited by Sulfate analogs, such as perchlorate. Previously, we showed pure culture SRM adaptation to perchlorate stress through mutation of the Sulfate Adenylyltransferase, a central enzyme in the Sulfate reduction pathway. Here, we explored adaptation to perchlorate across unconstrained SRM on a community scale. We followed natural and bio-augmented sulfidogenic communities through serial transfers in increasing concentrations of perchlorate. Our results demonstrated that perchlorate stress altered community structure by initially selecting for innately more resistant strains. Isolation, whole-genome sequencing, and molecular biology techniques allowed us to define subsequent genetic mechanisms of adaptation that arose across the dominant adapting SRM. Changes in the regulation of divalent anion:sodium symporter family transporters led to increased intracellular Sulfate to perchlorate ratios, allowing SRM to escape the effects of competitive inhibition. Thus, in contrast to pure-culture results, SRM in communities cope with perchlorate stress via changes in anion transport and its regulation. This highlights the value of probing evolutionary questions in an ecological framework, bridging the gap between ecology, evolution, genomics, and physiology.
-
adaptation of desulfovibrio alaskensis g20 to perchlorate a specific inhibitor of Sulfate reduction
Environmental Microbiology, 2019Co-Authors: Misha G Mehtakolte, Magdalena K Stoeva, Anchal Mehra, Steven A Redford, Matthew D Youngblut, Grant M Zane, Patrick Gregoire, Hans K Carlson, Judy D Wall, John D CoatesAbstract:Hydrogen sulfide produced by Sulfate-reducing microorganisms (SRM) poses significant health and economic risks, particularly during oil recovery. Previous studies identified perchlorate as a specific inhibitor of SRM. However, constant inhibitor addition to natural systems results in new selective pressures. Consequently, we investigated the ability of Desulfovibrio alaskensis G20 to evolve perchlorate resistance. Serial transfers in increasing concentrations of perchlorate led to robust growth in the presence of 100 mM inhibitor. Isolated adapted strains demonstrated a threefold increase in perchlorate resistance compared to the wild-type ancestor. Whole genome sequencing revealed a single base substitution in Dde_2265, the Sulfate Adenylyltransferase (sat). We purified and biochemically characterized the Sat from both wild-type and adapted strains, and showed that the adapted Sat was approximately threefold more resistant to perchlorate inhibition, mirroring whole cell results. The ability of this mutation to confer resistance across other inhibitors of sulfidogenesis was also assayed. The generalizability of this mutation was confirmed in multiple evolving G20 cultures and in another SRM, D. vulgaris Hildenborough. This work demonstrates that a single nucleotide polymorphism in Sat can have a significant impact on developing perchlorate resistance and emphasizes the value of adaptive laboratory evolution for understanding microbial responses to environmental perturbations.
Norbert Speich - One of the best experts on this subject based on the ideXlab platform.
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enzymology and molecular biology of Sulfate reduction in extremely thermophilic archaeon archaeoglobus fulgidus
Methods in Enzymology, 1994Co-Authors: Christiane Dahl, Norbert Speich, Hans G. TrüperAbstract:Publisher Summary This chapter describes enzymology and molecular biology of Sulfate reduction in Archaeoglobus fulgidus ( A. fulgidus ). A. fulgidus is an extreme thermophile and grows at temperatures between 64 and 92, with an optimum at 83. This organism carries out Sulfate reduction via the pathway originally proposed for bacterial species. Owing to its chemical inertia, Sulfate needs first to be activated to adenylylSulfate [adenosine-5′-phosphoSulfate (APS)] by ATP-sulfurylase [Sulfate Adenylyltransferase], with formation of pyrophosphate. The enzyme adenylylSulfate (APS) reductase catalyzes the reduction of APS to sulfite and AMP. Sulfite is finally reduced to sulfide by sulfite reductase. Auxiliary enzymes are widely applied in the determination of ATP sulfurylase and sulfite reductase activities from mesophilic organisms. ATP-sulfurylase from A. fulgidus is measured in the thermodynamically favored direction of ATP generation from the reaction of APS with pyrophosphate. The ATP formed is then spectrophotometrically determined. AdenylylSulfate reductase activity is measured in a continuous spectrophotometric assay in the direction of APS formation from sulfite and AMP with ferricyanide as electron acceptor.
