The Bifunctional Pyruvate Decarboxylase/Pyruvate Ferredoxin Oxidoreductase from<i>Thermococcus guaymasensis</i>

Eram, Mohammad S.; Oduaran, Erica; Ma, Kesen

doi:10.1155/2014/349379

Cited by 17 publications

(23 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Shaw et al also did not detect PDH or PDC activities by enzyme assay (which we have confirmed). There are reports that PFOR can decarboxylate pyruvate directly to acetaldehyde, functioning as pyruvate decarboxylase (PDC) in Pyrococcus furiosus [16] and Thermococcus guaymasensis [17]. Although in both cases, the acetyl-CoA production rates are higher than acetaldehyde production rates (roughly 5:1 in both organisms [17]), the PDC side activity of PFOR is still thought to be one of the options for acetaldehyde production in hyperthermophiles [17].…”

Section: Discussionmentioning

confidence: 99%

“…There are reports that PFOR can decarboxylate pyruvate directly to acetaldehyde, functioning as pyruvate decarboxylase (PDC) in Pyrococcus furiosus [16] and Thermococcus guaymasensis [17]. Although in both cases, the acetyl-CoA production rates are higher than acetaldehyde production rates (roughly 5:1 in both organisms [17]), the PDC side activity of PFOR is still thought to be one of the options for acetaldehyde production in hyperthermophiles [17]. Another possibility is through aldehyde ferredoxin oxidoreductase (AOR), which can convert acetate to acetaldehyde [18, 19].…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Physiological roles of pyruvate ferredoxin oxidoreductase and pyruvate formate-lyase in Thermoanaerobacterium saccharolyticum JW/SL-YS485

Jing-lun

Olson

Lanahan

et al. 2015

Biotechnol Biofuels

View full text Add to dashboard Cite

BackgroundThermoanaerobacter saccharolyticum is a thermophilic microorganism that has been engineered to produce ethanol at high titer (30–70 g/L) and greater than 90 % theoretical yield. However, few genes involved in pyruvate to ethanol production pathway have been unambiguously identified. In T. saccharolyticum, the products of six putative pfor gene clusters and one pfl gene may be responsible for the conversion of pyruvate to acetyl-CoA. To gain insights into the physiological roles of PFOR and PFL, we studied the effect of deletions of several genes thought to encode these activities.ResultsIt was found that pyruvate ferredoxin oxidoreductase enzyme (PFOR) is encoded by the pforA gene and plays a key role in pyruvate dissimilation. We further demonstrated that pyruvate formate-lyase activity (PFL) is encoded by the pfl gene. Although the pfl gene is normally expressed at low levels, it is crucial for biosynthesis in T. saccharolyticum. In pforA deletion strains, pfl expression increased and was able to partially compensate for the loss of PFOR activity. Deletion of both pforA and pfl resulted in a strain that required acetate and formate for growth and produced lactate as the primary fermentation product, achieving 88 % theoretical lactate yield.ConclusionPFOR encoded by Tsac_0046 and PFL encoded by Tsac_0628 are only two routes for converting pyruvate to acetyl-CoA in T. saccharolyticum. The physiological role of PFOR is pyruvate dissimilation, whereas that of PFL is supplying C1 units for biosynthesis.Electronic supplementary materialThe online version of this article (doi:10.1186/s13068-015-0304-1) contains supplementary material, which is available to authorized users.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Physiological roles of pyruvate ferredoxin oxidoreductase and pyruvate formate-lyase in Thermoanaerobacterium saccharolyticum JW/SL-YS485

Jing-lun

Olson

Lanahan

et al. 2015

Biotechnol Biofuels

View full text Add to dashboard Cite

show abstract

“…To this end, we searched for common physiological and biochemical characteristics among Archaea and plants. Strikingly, we noted that acetaldehyde biosynthesis machinery is indeed conserved exclusively in Archaea and plants 3,18,19 . In Archaea, pyruvate ferredoxin oxidoreductase (POR) converts pyruvate to acetaldehyde and pyruvate decarboxylase (PDC) performs the same function in plants (Fig: 3B).…”

Section: Nd Activity Is Rooted In the Archaeamentioning

confidence: 87%

Recruitment of Archaeal DTD is a Key Event in the Emergence of Land Plants

Mazeed

Singh

Kumar

et al. 2020

Preprint

View full text Add to dashboard Cite

Land plant evolution is a major leap in the history of life that took place during the Neoproterozoic Era (~800 Mya). Charophyceae, a class of rhyzophytic green algae emerged as a land plant with innovations in biochemical, cytological and developmental adaptations and played a crucial role in establishing life on the land 1,2 . One such striking architectural innovation is "root" that experience harsh environmental assaults such as floods, waterlogging and therefore is the epicentre for anaerobic fermentation, which produces toxic acetaldehyde 3 . Here, we show that such produced acetaldehyde makes N-ethyl-adducts on a central component of translation machinery aa-tRNA. The Plant kingdom is unique among life forms in possessing two chirality-based proofreading systems represented by Daminoacyl-tRNA deacylases (DTD1 and DTD2), derived from Bacteria and Archaea 4 . We identified a unique role of archaeal derived chiral proofreading module DTD2 that selectively deacylates N-ethyl-D-aminoacyl-tRNAs (NEDATs) in plants. NEDAT deacylase function is exclusive to DTD2, as no other proofreading modules with similar substrates like canonical DTD1 and peptidyl-tRNA hydrolase (PTH) can clear NEDATs. Thus, the study elucidates the cause of hypersensitivity of DTD2 knockout plants for both ethanol and acetaldehyde. We further show NEDAT elimination is rooted in Archaea which possess the biosynthesis machinery for ethanol fermentation similar to plants. While absent in other algal branches, DTD2 can be identified in plants from land plant ancestors-Charophytes onwards. DTD2 is the only gene that has only archaeal origin among the genes ascribed for architectural and genomic innovations that happened in the land plant ancestors. The work has uncovered an important gene transfer event from methanogenic archaea to the charophytes in the oldest terrestrial ecosystem bog that contains excess of D-amino acids and deprived of oxygen. 3 Plants being sedentary in their lifestyle are dependent on roots for their nourishment and root has to survive in the oxygen-deprived environment of soil. The soil also being enriched with D-amino acids makes roots clutched with inescapable stress of D-amino acids compounded with anaerobic stress. The presence of D-amino acids in plants is inevitable and play vital roles in plant physiology such as the development of the pollen tube and also act as a major nitrogen source 5 . On the contrary, D-amino acids also cause cellular toxicity by generating Daminoacyl-tRNAs (D-aa-tRNAs) which arrests free tRNA pool from translation. Removal of mischarged D-amino acids from D-aa-tRNAs is termed as chiral proofreading 6 that enables the perpetuation of homochirality in the cellular proteome 7 . D-amino acid editing modules are universally conserved; D-aminoacyl-tRNA deacylase 1 (DTD1) is present in both Bacteria and Eukaryotes and DTD2 is in Archaea and plants 4 . Plants are the only organisms that possess both the evolutionarily distinct chiral proofreading modules DTD1 and DTD2 8,9 . Surprisingly, DTD2 knock out...

show abstract

“…Por enzymes from other sources have additional activities, including hydrogenase and pyruvate decarboxylase (33,34), so it is possible that one of these activities is required for viability. It is also possible that one of the proteins in the porCDAB operon acts as a subunit for another required enzyme complex.…”

Section: Discussionmentioning

confidence: 99%

Genetic, Genomic, and Transcriptomic Studies of Pyruvate Metabolism in Methanosarcina barkeri Fusaro

2015

View full text Add to dashboard Cite

Pyruvate, a central intermediate in the carbon fixation pathway of methanogenic archaea, is rarely used as an energy source by these organisms. The sole exception to this rule is a genetically uncharacterized Methanosarcina barkeri mutant capable of using pyruvate as a sole energy and carbon source (the Pyr ؉ phenotype). Here, we provide evidence that suggests that the Pyr ؉ mutant is able to metabolize pyruvate by overexpressing pyruvate ferredoxin oxidoreductase (por) and mutating genes involved in central carbon metabolism. Genomic analysis showed that the Pyr ؉ strain has two mutations localized to Mbar_A1588, the biotin protein ligase subunit of the pyruvate carboxylase (pyc) operon, and Mbar_A2165, a putative transcriptional regulator. Mutants expressing the Mbar_A1588 mutation showed no growth defect compared to the wild type (WT), yet the strains lacked pyc activity. Recreation of the Mbar_A2165 mutation resulted in a 2-fold increase of Por activity and gene expression, suggesting a role in por transcriptional regulation. Further transcriptomic analysis revealed that Pyr ؉ strains also overexpress the gene encoding phosphoenolpyruvate carboxylase, indicating the presence of a previously uncharacterized route for synthesizing oxaloacetate in M. barkeri and explaining the unimpaired growth in the absence of Pyc. Surprisingly, stringent repression of the por operon was lethal, even when the media were supplemented with pyruvate and/or Casamino Acids, suggesting that por plays an unidentified essential function in M. barkeri. IMPORTANCEThe work presented here reveals a complex interaction between anabolic and catabolic pathways involving pyruvate metabolism in Methanosarcina barkeri Fusaro. Among the unexpected findings were an essential role for the enzyme pyruvate-ferredoxin oxidoreductase and an alternate pathway for synthesis of oxaloacetate. These results clarify the mechanism of methanogenic catabolism of pyruvate and expand our understanding of carbon assimilation in methanogens.A diverse group of strictly anaerobic archaea are responsible for virtually all biologically produced methane, making them key players in the global carbon cycle (1). These unusual microorganisms grow using a very limited number of substrates, obtaining all of their energy from the methanogenic process. While most methanogens use only H 2 -CO 2 or formate as growth substrates, members of the Methanosarcinales show some metabolic diversity, with many species using H 2 -CO 2 , various one-carbon (C 1 ) compounds (e.g., methanol, methylamines, and methyl-sulfides), and acetate as growth substrates. A few methanogenic species can use longerchain alcohols as energy sources, but these molecules are not assimilated. Instead, they are oxidized to provide the reducing equivalents needed for reduction of CO 2 to methane and then excreted (2). Larger organic compounds, such as sugars and fatty acids, are almost never substrates for methanogenic archaea, although they are cometabolized via syntrophic microbial communities (3). The...

show abstract

The Bifunctional Pyruvate Decarboxylase/Pyruvate Ferredoxin Oxidoreductase fromThermococcus guaymasensis

Cited by 17 publications

References 60 publications

Physiological roles of pyruvate ferredoxin oxidoreductase and pyruvate formate-lyase in Thermoanaerobacterium saccharolyticum JW/SL-YS485

Physiological roles of pyruvate ferredoxin oxidoreductase and pyruvate formate-lyase in Thermoanaerobacterium saccharolyticum JW/SL-YS485

Recruitment of Archaeal DTD is a Key Event in the Emergence of Land Plants

Genetic, Genomic, and Transcriptomic Studies of Pyruvate Metabolism in Methanosarcina barkeri Fusaro

Contact Info

Product

Resources

About