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García-Contreras R, de la Mora J, Mora-Montes HM, Martínez-Álvarez JA, Vicente-Gómez M, Padilla-Vaca F, Vargas-Maya NI, Franco B. The inorganic pyrophosphatases of microorganisms: a structural and functional review. PeerJ 2024; 12:e17496. [PMID: 38938619 PMCID: PMC11210485 DOI: 10.7717/peerj.17496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 05/09/2024] [Indexed: 06/29/2024] Open
Abstract
Pyrophosphatases (PPases) are enzymes that catalyze the hydrolysis of pyrophosphate (PPi), a byproduct of the synthesis and degradation of diverse biomolecules. The accumulation of PPi in the cell can result in cell death. Although the substrate is the same, there are variations in the catalysis and features of these enzymes. Two enzyme forms have been identified in bacteria: cytoplasmic or soluble pyrophosphatases and membrane-bound pyrophosphatases, which play major roles in cell bioenergetics. In eukaryotic cells, cytoplasmic enzymes are the predominant form of PPases (c-PPases), while membrane enzymes (m-PPases) are found only in protists and plants. The study of bacterial cytoplasmic and membrane-bound pyrophosphatases has slowed in recent years. These enzymes are central to cell metabolism and physiology since phospholipid and nucleic acid synthesis release important amounts of PPi that must be removed to allow biosynthesis to continue. In this review, two aims were pursued: first, to provide insight into the structural features of PPases known to date and that are well characterized, and to provide examples of enzymes with novel features. Second, the scientific community should continue studying these enzymes because they have many biotechnological applications. Additionally, in this review, we provide evidence that there are m-PPases present in fungi; to date, no examples have been characterized. Therefore, the diversity of PPase enzymes is still a fruitful field of research. Additionally, we focused on the roles of H+/Na+ pumps and m-PPases in cell bioenergetics. Finally, we provide some examples of the applications of these enzymes in molecular biology and biotechnology, especially in plants. This review is valuable for professionals in the biochemistry field of protein structure-function relationships and experts in other fields, such as chemistry, nanotechnology, and plant sciences.
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Affiliation(s)
- Rodolfo García-Contreras
- Departamento de Microbiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Javier de la Mora
- Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Héctor Manuel Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - José A. Martínez-Álvarez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Marcos Vicente-Gómez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Felipe Padilla-Vaca
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Naurú Idalia Vargas-Maya
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Bernardo Franco
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
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2
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Strauss J, Wilkinson C, Vidilaseris K, de Castro Ribeiro OM, Liu J, Hillier J, Wichert M, Malinen AM, Gehl B, Jeuken LJ, Pearson AR, Goldman A. Functional and structural asymmetry suggest a unifying principle for catalysis in membrane-bound pyrophosphatases. EMBO Rep 2024; 25:853-875. [PMID: 38182815 PMCID: PMC10897367 DOI: 10.1038/s44319-023-00037-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/27/2023] [Accepted: 12/01/2023] [Indexed: 01/07/2024] Open
Abstract
Membrane-bound pyrophosphatases (M-PPases) are homodimeric primary ion pumps that couple the transport of Na+- and/or H+ across membranes to the hydrolysis of pyrophosphate. Their role in the virulence of protist pathogens like Plasmodium falciparum makes them an intriguing target for structural and functional studies. Here, we show the first structure of a K+-independent M-PPase, asymmetric and time-dependent substrate binding in time-resolved structures of a K+-dependent M-PPase and demonstrate pumping-before-hydrolysis by electrometric studies. We suggest how key residues in helix 12, 13, and the exit channel loops affect ion selectivity and K+-activation due to a complex interplay of residues that are involved in subunit-subunit communication. Our findings not only explain ion selectivity in M-PPases but also why they display half-of-the-sites reactivity. Based on this, we propose, for the first time, a unified model for ion-pumping, hydrolysis, and energy coupling in all M-PPases, including those that pump both Na+ and H+.
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Affiliation(s)
- Jannik Strauss
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, UK
- Numaferm GmbH, Düsseldorf, Germany
| | - Craig Wilkinson
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, UK
| | - Keni Vidilaseris
- Molecular and Integrative Biosciences, Biological and Environmental Sciences, University of Helsinki, 00100, Helsinki, Finland
| | - Orquidea M de Castro Ribeiro
- Molecular and Integrative Biosciences, Biological and Environmental Sciences, University of Helsinki, 00100, Helsinki, Finland
| | - Jianing Liu
- Molecular and Integrative Biosciences, Biological and Environmental Sciences, University of Helsinki, 00100, Helsinki, Finland
| | - James Hillier
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, UK
- Bio-Rad Laboratories Ltd., Watford, UK
| | - Maximilian Wichert
- Leiden Institute of Chemistry, University Leiden, PO Box 9502, 2300 RA, Leiden, The Netherlands
| | - Anssi M Malinen
- Department of Life Technologies, University of Turku, FIN-20014, Turku, Finland
| | - Bernadette Gehl
- Molecular and Integrative Biosciences, Biological and Environmental Sciences, University of Helsinki, 00100, Helsinki, Finland
- Department of Applied Physics, Aalto University, FI-00076, AALTO, Espoo, Finland
| | - Lars Jc Jeuken
- Leiden Institute of Chemistry, University Leiden, PO Box 9502, 2300 RA, Leiden, The Netherlands
| | - Arwen R Pearson
- Institute for Nanostructure and Solid State Physics, Hamburg Centre for Ultrafast Imaging, Universität Hamburg, 22761, Hamburg, Germany
| | - Adrian Goldman
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, UK.
- Molecular and Integrative Biosciences, Biological and Environmental Sciences, University of Helsinki, 00100, Helsinki, Finland.
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3
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Sha L, Li J, Shen H, Wang Q, Meng P, Zhang X, Deng Y, Zhu W, Xu Q. LHPP-mediated inorganic pyrophosphate hydrolysis-driven lysosomal acidification in astrocytes regulates adult neurogenesis. Cell Rep 2023; 42:112975. [PMID: 37573508 DOI: 10.1016/j.celrep.2023.112975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 06/26/2023] [Accepted: 07/28/2023] [Indexed: 08/15/2023] Open
Abstract
In bacteria, archaea, protists, and plants, the hydrolysis of pyrophosphate (PPi) by inorganic pyrophosphatase (PPase) can, under stress conditions, substitute for ATP-driven proton flux to generate a proton gradient and induce luminal acidification. However, this strategy is considered to be lost in eukaryotes. Here, we report that LHPP, a poorly understood PPase that exhibits activity at acidic pH, is primarily expressed in astrocytes and partly localized on lysosomal membranes. Under stress conditions, LHPP is recruited to vacuolar ATPase (V-ATPase) and facilitates V-ATPase-dependent proton transport and lysosomal acidification by hydrolyzing PPi. LHPP knockout (KO) mice have no discernable phenotype but are resilient to chronic-stress-induced depression-like behaviors. Mechanistically, LHPP deficiency prevents lysosome-dependent degradation of C/EBPβ and induces the expression of a group of chemokines that promote adult neurogenesis. Together, these findings suggest that LHPP is likely to be a therapeutic target for stress-related brain disease.
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Affiliation(s)
- Longze Sha
- State Key Laboratory of Common Mechanism Research for Major Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China; Neuroscience Center, Chinese Academy of Medical Sciences, Beijing 100005, China
| | - Jing Li
- The National Clinical Research Center for Mental Disorders & Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100088, China
| | - Hui Shen
- State Key Laboratory of Common Mechanism Research for Major Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China; Center for Translational Medicine, Second Military Medical University, Shanghai 200433, China
| | - Qingyu Wang
- State Key Laboratory of Common Mechanism Research for Major Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China
| | - Peixin Meng
- State Key Laboratory of Common Mechanism Research for Major Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China
| | - Xiuneng Zhang
- State Key Laboratory of Common Mechanism Research for Major Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China
| | - Yu Deng
- State Key Laboratory of Common Mechanism Research for Major Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China
| | - Wanwan Zhu
- State Key Laboratory of Common Mechanism Research for Major Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China; Neuroscience Center, Chinese Academy of Medical Sciences, Beijing 100005, China
| | - Qi Xu
- State Key Laboratory of Common Mechanism Research for Major Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China; Neuroscience Center, Chinese Academy of Medical Sciences, Beijing 100005, China.
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H +-Translocating Membrane-Bound Pyrophosphatase from Rhodospirillum rubrum Fuels Escherichia coli Cells via an Alternative Pathway for Energy Generation. Microorganisms 2023; 11:microorganisms11020294. [PMID: 36838259 PMCID: PMC9959109 DOI: 10.3390/microorganisms11020294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/11/2023] [Accepted: 01/14/2023] [Indexed: 01/24/2023] Open
Abstract
Inorganic pyrophosphatases (PPases) catalyze an essential reaction, namely, the hydrolysis of PPi, which is formed in large quantities as a side product of numerous cellular reactions. In the majority of living species, PPi hydrolysis is carried out by soluble cytoplasmic PPase (S-PPases) with the released energy dissipated in the form of heat. In Rhodospirillum rubrum, part of this energy can be conserved by proton-pumping pyrophosphatase (H+-PPaseRru) in the form of a proton electrochemical gradient for further ATP synthesis. Here, the codon-harmonized gene hppaRru encoding H+-PPaseRru was expressed in the Escherichia coli chromosome. We demonstrate, for the first time, that H+-PPaseRru complements the essential native S-PPase in E. coli cells. 13C-MFA confirmed that replacing native PPase to H+-PPaseRru leads to the re-distribution of carbon fluxes; a statistically significant 36% decrease in tricarboxylic acid (TCA) cycle fluxes was found compared with wild-type E. coli MG1655. Such a flux re-distribution can indicate the presence of an additional method for energy generation (e.g., ATP), which can be useful for the microbiological production of a number of compounds, the biosynthesis of which requires the consumption of ATP.
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Malinen AM, Anashkin VA, Orlov VN, Bogachev AV, Lahti R, Baykov AA. Pre‐steady‐state kinetics and solvent isotope effects support the “billiard‐type” transport mechanism in
Na
+
‐translocating pyrophosphatase. Protein Sci 2022; 31:e4394. [PMID: 36040263 PMCID: PMC9405524 DOI: 10.1002/pro.4394] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 06/23/2022] [Accepted: 07/12/2022] [Indexed: 11/10/2022]
Abstract
Membrane‐bound pyrophosphatase (mPPase) found in microbes and plants is a membrane H+ pump that transports the H+ ion generated in coupled pyrophosphate hydrolysis out of the cytoplasm. Certain bacterial and archaeal mPPases can in parallel transport Na+ via a hypothetical “billiard‐type” mechanism, also involving the hydrolysis‐generated proton. Here, we present the functional evidence supporting this coupling mechanism. Rapid‐quench and pulse‐chase measurements with [32P]pyrophosphate indicated that the chemical step (pyrophosphate hydrolysis) is rate‐limiting in mPPase catalysis and is preceded by a fast isomerization of the enzyme‐substrate complex. Na+, whose binding is a prerequisite for the hydrolysis step, is not required for substrate binding. Replacement of H2O with D2O decreased the rates of pyrophosphate hydrolysis by both Na+‐ and H+‐transporting bacterial mPPases, the effect being more significant than with a non‐transporting soluble pyrophosphatase. We also show that the Na+‐pumping mPPase of Thermotoga maritima resembles other dimeric mPPases in demonstrating negative kinetic cooperativity and the requirement for general acid catalysis. The findings point to a crucial role for the hydrolysis‐generated proton both in H+‐pumping and Na+‐pumping by mPPases.
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Affiliation(s)
- Anssi M. Malinen
- Department of Life Technologies University of Turku Turku Finland
| | - Viktor A. Anashkin
- Belozersky Institute of Physico‐Chemical Biology Lomonosov Moscow State University Moscow Russia
| | - Victor N. Orlov
- Belozersky Institute of Physico‐Chemical Biology Lomonosov Moscow State University Moscow Russia
| | - Alexander V. Bogachev
- Belozersky Institute of Physico‐Chemical Biology Lomonosov Moscow State University Moscow Russia
| | - Reijo Lahti
- Department of Life Technologies University of Turku Turku Finland
| | - Alexander A. Baykov
- Belozersky Institute of Physico‐Chemical Biology Lomonosov Moscow State University Moscow Russia
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6
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Baykov AA, Anashkin VA, Malinen AM, Bogachev AV. The Mechanism of Energy Coupling in H +/Na +-Pumping Membrane Pyrophosphatase-Possibilities and Probabilities. Int J Mol Sci 2022; 23:9504. [PMID: 36012762 PMCID: PMC9408878 DOI: 10.3390/ijms23169504] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 08/12/2022] [Accepted: 08/21/2022] [Indexed: 11/17/2022] Open
Abstract
Membrane pyrophosphatases (mPPases) found in plant vacuoles and some prokaryotes and protists are ancient cation pumps that couple pyrophosphate hydrolysis with the H+ and/or Na+ transport out of the cytoplasm. Because this function is reversible, mPPases play a role in maintaining the level of cytoplasmic pyrophosphate, a known regulator of numerous metabolic reactions. mPPases arouse interest because they are among the simplest membrane transporters and have no homologs among known ion pumps. Detailed phylogenetic studies have revealed various subtypes of mPPases and suggested their roles in the evolution of the "sodium" and "proton" bioenergetics. This treatise focuses on the mechanistic aspects of the transport reaction, namely, the coupling step, the role of the chemically produced proton, subunit cooperation, and the relationship between the proton and sodium ion transport. The available data identify H+-PPases as the first non-oxidoreductase pump with a "direct-coupling" mechanism, i.e., the transported proton is produced in the coupled chemical reaction. They also support a "billiard" hypothesis, which unifies the H+ and Na+ transport mechanisms in mPPase and, probably, other transporters.
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Affiliation(s)
- Alexander A. Baykov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119899, Russia
| | - Viktor A. Anashkin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119899, Russia
| | - Anssi M. Malinen
- Department of Life Technologies, University of Turku, FIN-20014 Turku, Finland
| | - Alexander V. Bogachev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119899, Russia
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7
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Maitra S, Brestic M, Bhadra P, Shankar T, Praharaj S, Palai JB, Shah MMR, Barek V, Ondrisik P, Skalický M, Hossain A. Bioinoculants-Natural Biological Resources for Sustainable Plant Production. Microorganisms 2021; 10:51. [PMID: 35056500 PMCID: PMC8780112 DOI: 10.3390/microorganisms10010051] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 12/21/2021] [Accepted: 12/23/2021] [Indexed: 11/22/2022] Open
Abstract
Agricultural sustainability is of foremost importance for maintaining high food production. Irresponsible resource use not only negatively affects agroecology, but also reduces the economic profitability of the production system. Among different resources, soil is one of the most vital resources of agriculture. Soil fertility is the key to achieve high crop productivity. Maintaining soil fertility and soil health requires conscious management effort to avoid excessive nutrient loss, sustain organic carbon content, and minimize soil contamination. Though the use of chemical fertilizers have successfully improved crop production, its integration with organic manures and other bioinoculants helps in improving nutrient use efficiency, improves soil health and to some extent ameliorates some of the constraints associated with excessive fertilizer application. In addition to nutrient supplementation, bioinoculants have other beneficial effects such as plant growth-promoting activity, nutrient mobilization and solubilization, soil decontamination and/or detoxification, etc. During the present time, high energy based chemical inputs also caused havoc to agriculture because of the ill effects of global warming and climate change. Under the consequences of climate change, the use of bioinputs may be considered as a suitable mitigation option. Bioinoculants, as a concept, is not something new to agricultural science, however; it is one of the areas where consistent innovations have been made. Understanding the role of bioinoculants, the scope of their use, and analysing their performance in various environments are key to the successful adaptation of this technology in agriculture.
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Affiliation(s)
- Sagar Maitra
- Department of Agronomy, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India; (S.M.); (T.S.); (S.P.); (J.B.P.)
| | - Marian Brestic
- Department of Plant Physiology, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 01 Nitra, Slovakia;
- Department of Botany and Plant Physiology, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic;
| | - Preetha Bhadra
- Department of Biotechnology, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India;
| | - Tanmoy Shankar
- Department of Agronomy, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India; (S.M.); (T.S.); (S.P.); (J.B.P.)
| | - Subhashisa Praharaj
- Department of Agronomy, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India; (S.M.); (T.S.); (S.P.); (J.B.P.)
| | - Jnana Bharati Palai
- Department of Agronomy, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India; (S.M.); (T.S.); (S.P.); (J.B.P.)
| | | | - Viliam Barek
- Department of Water Resources and Environmental Engineering, Faculty of Horticulture and Landscape Engineering, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 01 Nitra, Slovakia;
| | - Peter Ondrisik
- Department of Plant Physiology, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 01 Nitra, Slovakia;
| | - Milan Skalický
- Department of Botany and Plant Physiology, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic;
| | - Akbar Hossain
- Bangladesh Wheat and Maize Research Institute, Dinajpur 5200, Bangladesh;
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8
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Functional analysis of H +-pumping membrane-bound pyrophosphatase, ADP-glucose synthase, and pyruvate phosphate dikinase as pyrophosphate sources in Clostridium thermocellum. Appl Environ Microbiol 2021; 88:e0185721. [PMID: 34936842 PMCID: PMC8863071 DOI: 10.1128/aem.01857-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The atypical glycolysis of Clostridium thermocellum is characterized by the use of pyrophosphate (PPi) as phosphoryl donor for phosphofructokinase (Pfk) and pyruvate phosphate dikinase (Ppdk) reactions. Previously, biosynthetic PPi was calculated to be stoichiometrically insufficient to drive glycolysis. This study investigates the role of a H+-pumping membrane-bound pyrophosphatase, glycogen cycling, a predicted Ppdk-malate shunt cycle and acetate cycling in generating PPi. Knockout studies and enzyme assays confirmed that clo1313_0823 encodes a membrane-bound pyrophosphatase. Additionally, clo1313_0717-0718 was confirmed to encode ADP-glucose synthase by knockouts, glycogen measurements in C. thermocellum and heterologous expression in E. coli. Unexpectedly, individually-targeted gene deletions of the four putative PPi sources did not have a significant phenotypic effect. Although combinatorial deletion of all four putative PPi sources reduced the growth rate by 22% (0.30±0.01 h-1) and the biomass yield by 38% (0.18±0.00 gbiomass gsubstrate-1), this change was much smaller than what would be expected for stoichiometrically essential PPi-supplying mechanisms. Growth-arrested cells of the quadruple knockout readily fermented cellobiose indicating that the unknown PPi-supplying mechanisms are independent of biosynthesis. An alternative hypothesis that ATP-dependent Pfk activity circumvents a need for PPi altogether, was falsified by enzyme assays, heterologous expression of candidate genes and whole-genome sequencing. As a secondary outcome, enzymatic assays confirmed functional annotation of clo1313_1832 as ATP- and GTP-dependent fructokinase. These results indicate that the four investigated PPi sources individually and combined play no significant PPi-supplying role and the true source(s) of PPi, or alternative phosphorylating mechanisms, that drive glycolysis in C. thermocellum remain(s) elusive. IMPORTANCE Increased understanding of the central metabolism of C. thermocellum is important from a fundamental as well as from a sustainability and industrial perspective. In addition to showing that H+-pumping membrane-bound PPase, glycogen cycling, a Ppdk-malate shunt cycle, and acetate cycling are not significant sources of PPi supply, this study adds functional annotation of four genes and availability of an updated PPi stoichiometry from biosynthesis to the scientific domain. Together, this aids future metabolic engineering attempts aimed to improve C. thermocellum as a cell factory for sustainable and efficient production of ethanol from lignocellulosic material through consolidated bioprocessing with minimal pretreatment. Getting closer to elucidating the elusive source of PPi, or alternative phosphorylating mechanisms, for the atypical glycolysis is itself of fundamental importance. Additionally, the findings of this study directly contribute to investigations into trade-offs between thermodynamic driving force versus energy yield of PPi- and ATP-dependent glycolysis.
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9
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A Lumenal Loop Associated with Catalytic Asymmetry in Plant Vacuolar H +-Translocating Pyrophosphatase. Int J Mol Sci 2021; 22:ijms222312902. [PMID: 34884707 PMCID: PMC8657866 DOI: 10.3390/ijms222312902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 11/27/2021] [Indexed: 12/13/2022] Open
Abstract
Membrane-integral inorganic pyrophosphatases (mPPases) couple pyrophosphate hydrolysis with H+ and Na+ pumping in plants and microbes. mPPases are homodimeric transporters with two catalytic sites facing the cytoplasm and demonstrating highly different substrate-binding affinities and activities. The structural aspects of the functional asymmetry are still poorly understood because the structure of the physiologically relevant dimer form with only one active site occupied by the substrate is unknown. We addressed this issue by molecular dynamics (MD) simulations of the H+-transporting mPPase of Vigna radiata, starting from its crystal structure containing a close substrate analog (imidodiphosphate, IDP) in both active sites. The MD simulations revealed pre-existing subunit asymmetry, which increased upon IDP binding to one subunit and persisted in the fully occupied dimer. The most significant asymmetrical change caused by IDP binding is a ‘rigid body’-like displacement of the lumenal loop connecting α-helices 2 and 3 in the partner subunit and opening its exit channel for water. This highly conserved 14–19-residue loop is found only in plant vacuolar mPPases and may have a regulatory function, such as pH sensing in the vacuole. Our data define the structural link between the loop and active sites and are consistent with the published structural and functional data.
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10
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Johansson NG, Dreano L, Vidilaseris K, Khattab A, Liu J, Lasbleiz A, Ribeiro O, Kiriazis A, Boije af Gennäs G, Meri S, Goldman A, Yli‐Kauhaluoma J, Xhaard H. Exploration of Pyrazolo[1,5-a]pyrimidines as Membrane-Bound Pyrophosphatase Inhibitors. ChemMedChem 2021; 16:3360-3367. [PMID: 34459148 PMCID: PMC8597055 DOI: 10.1002/cmdc.202100392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 08/03/2021] [Indexed: 11/08/2022]
Abstract
Inhibition of membrane-bound pyrophosphatase (mPPase) with small molecules offer a new approach in the fight against pathogenic protozoan parasites. mPPases are absent in humans, but essential for many protists as they couple pyrophosphate hydrolysis to the active transport of protons or sodium ions across acidocalcisomal membranes. So far, only few nonphosphorus inhibitors have been reported. Here, we explore the chemical space around previous hits using a combination of screening and synthetic medicinal chemistry, identifying compounds with low micromolar inhibitory activities in the Thermotoga maritima mPPase test system. We furthermore provide early structure-activity relationships around a new scaffold having a pyrazolo[1,5-a]pyrimidine core. The most promising pyrazolo[1,5-a]pyrimidine congener was further investigated and found to inhibit Plasmodium falciparum mPPase in membranes as well as the growth of P. falciparum in an ex vivo survival assay.
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Affiliation(s)
- Niklas G. Johansson
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of PharmacyUniversity of HelsinkiP.O. Box 56 (Viikinkaari 5 E)00014HelsinkiFinland
| | - Loïc Dreano
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of PharmacyUniversity of HelsinkiP.O. Box 56 (Viikinkaari 5 E)00014HelsinkiFinland
| | - Keni Vidilaseris
- Department of Biosciences, Division of BiochemistryUniversity of HelsinkiP.O. Box 56 (Viikinkaari 9)00014HelsinkiFinland
| | - Ayman Khattab
- Malaria Research Laboratory, Translational Immunology Research Program, Department of Bacteriology and Immunology, Haartman InstituteUniversity of HelsinkiP.O. Box 21 (Haartmaninkatu 3)00014HelsinkiFinland
| | - Jianing Liu
- Department of Biosciences, Division of BiochemistryUniversity of HelsinkiP.O. Box 56 (Viikinkaari 9)00014HelsinkiFinland
| | - Arthur Lasbleiz
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of PharmacyUniversity of HelsinkiP.O. Box 56 (Viikinkaari 5 E)00014HelsinkiFinland
| | - Orquidea Ribeiro
- Department of Biosciences, Division of BiochemistryUniversity of HelsinkiP.O. Box 56 (Viikinkaari 9)00014HelsinkiFinland
| | - Alexandros Kiriazis
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of PharmacyUniversity of HelsinkiP.O. Box 56 (Viikinkaari 5 E)00014HelsinkiFinland
| | - Gustav Boije af Gennäs
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of PharmacyUniversity of HelsinkiP.O. Box 56 (Viikinkaari 5 E)00014HelsinkiFinland
| | - Seppo Meri
- Malaria Research Laboratory, Translational Immunology Research Program, Department of Bacteriology and Immunology, Haartman InstituteUniversity of HelsinkiP.O. Box 21 (Haartmaninkatu 3)00014HelsinkiFinland
| | - Adrian Goldman
- Department of Biosciences, Division of BiochemistryUniversity of HelsinkiP.O. Box 56 (Viikinkaari 9)00014HelsinkiFinland
- School of Biomedical Sciences and Astbury Centre for Structural Molecular BiologyUniversity of Leeds, Clarendon WayLeeds LS2 9JTUK
| | - Jari Yli‐Kauhaluoma
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of PharmacyUniversity of HelsinkiP.O. Box 56 (Viikinkaari 5 E)00014HelsinkiFinland
| | - Henri Xhaard
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of PharmacyUniversity of HelsinkiP.O. Box 56 (Viikinkaari 5 E)00014HelsinkiFinland
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11
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Anashkin VA, Malinen AM, Bogachev AV, Baykov AA. Catalytic Asymmetry in Homodimeric H +-Pumping Membrane Pyrophosphatase Demonstrated by Non-Hydrolyzable Pyrophosphate Analogs. Int J Mol Sci 2021; 22:ijms22189820. [PMID: 34575984 PMCID: PMC8469034 DOI: 10.3390/ijms22189820] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 08/23/2021] [Accepted: 09/08/2021] [Indexed: 02/08/2023] Open
Abstract
Membrane-bound inorganic pyrophosphatase (mPPase) resembles the F-ATPase in catalyzing polyphosphate-energized H+ and Na+ transport across lipid membranes, but differs structurally and mechanistically. Homodimeric mPPase likely uses a “direct coupling” mechanism, in which the proton generated from the water nucleophile at the entrance to the ion conductance channel is transported across the membrane or triggers Na+ transport. The structural aspects of this mechanism, including subunit cooperation, are still poorly understood. Using a refined enzyme assay, we examined the inhibition of K+-dependent H+-transporting mPPase from Desulfitobacterium hafniensee by three non-hydrolyzable PPi analogs (imidodiphosphate and C-substituted bisphosphonates). The kinetic data demonstrated negative cooperativity in inhibitor binding to two active sites, and reduced active site performance when the inhibitor or substrate occupied the other active site. The nonequivalence of active sites in PPi hydrolysis in terms of the Michaelis constant vanished at a low (0.1 mM) concentration of Mg2+ (essential cofactor). The replacement of K+, the second metal cofactor, by Na+ increased the substrate and inhibitor binding cooperativity. The detergent-solubilized form of mPPase exhibited similar active site nonequivalence in PPi hydrolysis. Our findings support the notion that the mPPase mechanism combines Mitchell’s direct coupling with conformational coupling to catalyze cation transport across the membrane.
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Affiliation(s)
- Viktor A. Anashkin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119899 Moscow, Russia; (V.A.A.); (A.V.B.)
| | - Anssi M. Malinen
- Department of Life Technologies, University of Turku, FIN-20014 Turku, Finland;
| | - Alexander V. Bogachev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119899 Moscow, Russia; (V.A.A.); (A.V.B.)
| | - Alexander A. Baykov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119899 Moscow, Russia; (V.A.A.); (A.V.B.)
- Correspondence:
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12
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Li YX, Rao YZ, Qi YL, Qu YN, Chen YT, Jiao JY, Shu WS, Jiang H, Hedlund BP, Hua ZS, Li WJ. Deciphering Symbiotic Interactions of " Candidatus Aenigmarchaeota" with Inferred Horizontal Gene Transfers and Co-occurrence Networks. mSystems 2021; 6:e0060621. [PMID: 34313464 PMCID: PMC8407114 DOI: 10.1128/msystems.00606-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 07/09/2021] [Indexed: 11/30/2022] Open
Abstract
"Candidatus Aenigmarchaeota" ("Ca. Aenigmarchaeota") represents one of the earliest proposed evolutionary branches within the Diapherotrites, Parvarchaeota, Aenigmarchaeota, Nanoarchaeota, and Nanohaloarchaeota (DPANN) superphylum. However, their ecological roles and potential host-symbiont interactions are still poorly understood. Here, eight metagenome-assembled genomes (MAGs) were reconstructed from hot spring ecosystems, and further in-depth comparative and evolutionary genomic analyses were conducted on these MAGs and other genomes downloaded from public databases. Although with limited metabolic capacities, we reported that "Ca. Aenigmarchaeota" in thermal environments harbor more genes related to carbohydrate metabolism than "Ca. Aenigmarchaeota" in nonthermal environments. Evolutionary analyses suggested that members from the Thaumarchaeota, Aigarchaeota, Crenarchaeota, and Korarchaeota (TACK) superphylum and Euryarchaeota contribute substantially to the niche expansion of "Ca. Aenigmarchaeota" via horizontal gene transfer (HGT), especially genes related to virus defense and stress responses. Based on co-occurrence network results and recent genetic exchanges among community members, we conjectured that "Ca. Aenigmarchaeota" may be symbionts associated with one MAG affiliated with the genus Pyrobaculum, though host specificity might be wide and variable across different "Ca. Aenigmarchaeota" organisms. This study provides significant insight into possible DPANN-host interactions and ecological roles of "Ca. Aenigmarchaeota." IMPORTANCE Recent advances in sequencing technology promoted the blowout discovery of super tiny microbes in the Diapherotrites, Parvarchaeota, Aenigmarchaeota, Nanoarchaeota, and Nanohaloarchaeota (DPANN) superphylum. However, the unculturable properties of the majority of microbes impeded our investigation of their behavior and symbiotic lifestyle in the corresponding community. By integrating horizontal gene transfer (HGT) detection and co-occurrence network analysis on "Candidatus Aenigmarchaeota" ("Ca. Aenigmarchaeota"), we made one of the first attempts to infer their putative interaction partners and further decipher the potential functional and genetic interactions between the symbionts. We revealed that HGTs contributed by members from the Thaumarchaeota, Aigarchaeota, Crenarchaeota, and Korarchaeota (TACK) superphylum and Euryarchaeota conferred "Ca. Aenigmarchaeota" with the ability to survive under different environmental stresses, such as virus infection, high temperature, and oxidative stress. This study demonstrates that the interaction partners might be inferable by applying informatics analyses on metagenomic sequencing data.
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Affiliation(s)
- Yu-Xian Li
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Yang-Zhi Rao
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Yan-Ling Qi
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Yan-Ni Qu
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Ya-Ting Chen
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Jian-Yu Jiao
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Wen-Sheng Shu
- School of Life Sciences, South China Normal University, Guangzhou, People’s Republic of China
| | - Hongchen Jiang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, People’s Republic of China
| | - Brian P. Hedlund
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, Nevada, USA
- Nevada Institute of Personalized Medicine, University of Nevada Las Vegas, Las Vegas, Nevada, USA
| | - Zheng-Shuang Hua
- Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, People’s Republic of China
| | - Wen-Jun Li
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, People’s Republic of China
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, People’s Republic of China
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13
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A human respiratory tract-associated bacterium with an extremely small genome. Commun Biol 2021; 4:628. [PMID: 34040152 PMCID: PMC8155191 DOI: 10.1038/s42003-021-02162-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 04/28/2021] [Indexed: 01/05/2023] Open
Abstract
Recent advances in culture-independent microbiological analyses have greatly expanded our understanding of the diversity of unculturable microbes. However, human pathogenic bacteria differing significantly from known taxa have rarely been discovered. Here, we present the complete genome sequence of an uncultured bacterium detected in human respiratory tract named IOLA, which was determined by developing a protocol to selectively amplify extremely AT-rich genomes. The IOLA genome is 303,838 bp in size with a 20.7% GC content, making it the smallest and most AT-rich genome among known human-associated bacterial genomes to our best knowledge and comparable to those of insect endosymbionts. While IOLA belongs to order Rickettsiales (mostly intracellular parasites), the gene content suggests an epicellular parasitic lifestyle. Surveillance of clinical samples provides evidence that IOLA can be predominantly detected in patients with respiratory bacterial infections and can persist for at least 15 months in the respiratory tract, suggesting that IOLA is a human respiratory tract-associated bacterium. Kazumasa Fukuda et al. complete a new genome sequence for an uncultured bacterium detected in human respiratory tract named IOLA. The IOLA genome is found to be among the smallest and most AT-rich of known human-associated bacterial genomes and surveillance of clinical samples indicates that IOLA is in fact a human respiratory tract-associated bacterium.
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14
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Auger C, Vinaik R, Appanna VD, Jeschke MG. Beyond mitochondria: Alternative energy-producing pathways from all strata of life. Metabolism 2021; 118:154733. [PMID: 33631145 PMCID: PMC8052308 DOI: 10.1016/j.metabol.2021.154733] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/09/2021] [Accepted: 02/13/2021] [Indexed: 12/12/2022]
Abstract
It is well-established that mitochondria are the powerhouses of the cell, producing adenosine triphosphate (ATP), the universal energy currency. However, the most significant strengths of the electron transport chain (ETC), its intricacy and efficiency, are also its greatest downfalls. A reliance on metal complexes (FeS clusters, hemes), lipid moities such as cardiolipin, and cofactors including alpha-lipoic acid and quinones render oxidative phosphorylation vulnerable to environmental toxins, intracellular reactive oxygen species (ROS) and fluctuations in diet. To that effect, it is of interest to note that temporal disruptions in ETC activity in most organisms are rarely fatal, and often a redundant number of failsafes are in place to permit continued ATP production when needed. Here, we highlight the metabolic reconfigurations discovered in organisms ranging from parasitic Entamoeba to bacteria such as pseudomonads and then complex eukaryotic systems that allow these species to adapt to and occasionally thrive in harsh environments. The overarching aim of this review is to demonstrate the plasticity of metabolic networks and recognize that in times of duress, life finds a way.
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Affiliation(s)
- Christopher Auger
- Ross Tilley Burn Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada
| | - Roohi Vinaik
- University of Toronto, Toronto, Ontario M5S 1A1, Canada
| | | | - Marc G Jeschke
- Ross Tilley Burn Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada; University of Toronto, Toronto, Ontario M5S 1A1, Canada.
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15
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Pyrophosphate as an alternative energy currency in plants. Biochem J 2021; 478:1515-1524. [PMID: 33881486 DOI: 10.1042/bcj20200940] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/20/2021] [Accepted: 03/23/2021] [Indexed: 02/07/2023]
Abstract
In the conditions of [Mg2+] elevation that occur, in particular, under low oxygen stress and are the consequence of the decrease in [ATP] and increase in [ADP] and [AMP], pyrophosphate (PPi) can function as an alternative energy currency in plant cells. In addition to its production by various metabolic pathways, PPi can be synthesized in the combined reactions of pyruvate, phosphate dikinase (PPDK) and pyruvate kinase (PK) by so-called PK/PPDK substrate cycle, and in the reverse reaction of membrane-bound H+-pyrophosphatase, which uses the energy of electrochemical gradients generated on tonoplast and plasma membrane. The PPi can then be consumed in its active forms of MgPPi and Mg2PPi by PPi-utilizing enzymes, which require an elevated [Mg2+]. This ensures a continuous operation of glycolysis in the conditions of suppressed ATP synthesis, keeping metabolism energy efficient and less dependent on ATP.
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16
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Baykov AA, Anashkin VA, Malinen AM. Good-Practice Non-Radioactive Assays of Inorganic Pyrophosphatase Activities. Molecules 2021; 26:molecules26082356. [PMID: 33919593 PMCID: PMC8073611 DOI: 10.3390/molecules26082356] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 04/15/2021] [Accepted: 04/16/2021] [Indexed: 01/19/2023] Open
Abstract
Inorganic pyrophosphatase (PPase) is a ubiquitous enzyme that converts pyrophosphate (PPi) to phosphate and, in this way, controls numerous biosynthetic reactions that produce PPi as a byproduct. PPase activity is generally assayed by measuring the product of the hydrolysis reaction, phosphate. This reaction is reversible, allowing PPi synthesis measurements and making PPase an excellent model enzyme for the study of phosphoanhydride bond formation. Here we summarize our long-time experience in measuring PPase activity and overview three types of the assay that are found most useful for (a) low-substrate continuous monitoring of PPi hydrolysis, (b) continuous and fixed-time measurements of PPi synthesis, and (c) high-throughput procedure for screening purposes. The assays are based on the color reactions between phosphomolybdic acid and triphenylmethane dyes or use a coupled ATP sulfurylase/luciferase enzyme assay. We also provide procedures to estimate initial velocity from the product formation curve and calculate the assay medium’s composition, whose components are involved in multiple equilibria.
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Affiliation(s)
- Alexander A. Baykov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119899 Moscow, Russia;
- Correspondence: (A.A.B.); (A.M.M.)
| | - Viktor A. Anashkin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119899 Moscow, Russia;
| | - Anssi M. Malinen
- Department of Life Technologies, University of Turku, FIN-20014 Turku, Finland
- Correspondence: (A.A.B.); (A.M.M.)
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17
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Damashek J, Okotie-Oyekan AO, Gifford SM, Vorobev A, Moran MA, Hollibaugh JT. Transcriptional activity differentiates families of Marine Group II Euryarchaeota in the coastal ocean. ISME COMMUNICATIONS 2021; 1:5. [PMID: 37938231 PMCID: PMC9723583 DOI: 10.1038/s43705-021-00002-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/14/2021] [Accepted: 01/20/2021] [Indexed: 11/09/2023]
Abstract
Marine Group II Euryarchaeota (Candidatus Poseidoniales), abundant but yet-uncultivated members of marine microbial communities, are thought to be (photo)heterotrophs that metabolize dissolved organic matter (DOM), such as lipids and peptides. However, little is known about their transcriptional activity. We mapped reads from a metatranscriptomic time series collected at Sapelo Island (GA, USA) to metagenome-assembled genomes to determine the diversity of transcriptionally active Ca. Poseidoniales. Summer metatranscriptomes had the highest abundance of Ca. Poseidoniales transcripts, mostly from the O1 and O3 genera within Ca. Thalassarchaeaceae (MGIIb). In contrast, transcripts from fall and winter samples were predominantly from Ca. Poseidoniaceae (MGIIa). Genes encoding proteorhodopsin, membrane-bound pyrophosphatase, peptidase/proteases, and part of the ß-oxidation pathway were highly transcribed across abundant genera. Highly transcribed genes specific to Ca. Thalassarchaeaceae included xanthine/uracil permease and receptors for amino acid transporters. Enrichment of Ca. Thalassarchaeaceae transcript reads related to protein/peptide, nucleic acid, and amino acid transport and metabolism, as well as transcript depletion during dark incubations, provided further evidence of heterotrophic metabolism. Quantitative PCR analysis of South Atlantic Bight samples indicated consistently abundant Ca. Poseidoniales in nearshore and inshore waters. Together, our data suggest that Ca. Thalassarchaeaceae are important photoheterotrophs potentially linking DOM and nitrogen cycling in coastal waters.
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Affiliation(s)
- Julian Damashek
- Department of Marine Sciences, University of Georgia, Athens, GA, USA.
- Department of Biology, Utica College, Utica, NY, USA.
| | - Aimee Oyinlade Okotie-Oyekan
- Department of Marine Sciences, University of Georgia, Athens, GA, USA
- Environmental Studies Program, University of Oregon, Eugene, OR, USA
| | | | - Alexey Vorobev
- Department of Marine Sciences, University of Georgia, Athens, GA, USA
- INSERM U932, PSL University, Institut Curie, Paris, France
| | - Mary Ann Moran
- Department of Marine Sciences, University of Georgia, Athens, GA, USA
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18
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Recent developments in molecular sensor designs for inorganic pyrophosphate detection and biological imaging. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2020.213744] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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19
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Niu H, Zhu J, Qu Q, Zhou X, Huang X, Du Z. Crystallographic and modeling study of the human inorganic pyrophosphatase 1: A potential anti-cancer drug target. Proteins 2021; 89:853-865. [PMID: 33583053 DOI: 10.1002/prot.26064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 11/09/2020] [Accepted: 01/31/2021] [Indexed: 11/10/2022]
Abstract
Inorganic pyrophosphatases (PPases) catalyze the hydrolysis of pyrophosphate to phosphates. PPases play essential roles in growth and development, and are found in all kingdoms of life. Human possess two PPases, PPA1 and PPA2. PPA1 is present in all tissues, acting largely as a housekeeping enzyme. Besides pyrophosphate hydrolysis, PPA1 can also directly dephosphorylate phosphorylated c-Jun N-terminal kinases 1 (JNK1). Upregulated expression of PPA1 has been linked to many human malignant tumors. PPA1 knockdown induces apoptosis and decreases proliferation. PPA1 is emerging as a potential prognostic biomarker and target for anti-cancer drug development. In spite of the biological and physiopathological importance of PPA1, there is no detailed study on the structure and catalytic mechanisms of mammalian origin PPases. Here we report the crystal structure of human PPA1 at a resolution of 2.4 Å. We also carried out modeling studies of PPA1 in complex with JNK1 derived phosphor-peptides. The monomeric protein fold of PPA1 is similar to those found in other family I PPases. PPA1 forms a dimeric structure that should be conserved in animal and fungal PPases. Analysis of the PPA1 structure and comparison with available structures of PPases from lower organisms suggest that PPA1 has a largely pre-organized and relatively rigid active site for pyrophosphate hydrolysis. Results from the modeling study indicate the active site of PPA1 has the potential to accommodate double-phosphorylated peptides from JNK1. In short, results from the study provides new insights into the mechanisms of human PPA1 and basis for structure-based anti-cancer drug developments using PPA1 as the target.
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Affiliation(s)
- Haiying Niu
- Department of Gynecology and Obstetrics, Tianjin First Central Hospital, Tianjin, China.,Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Illinois, USA
| | - Jiang Zhu
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Illinois, USA.,Department of Biochemistry and Molecular Biology, Pennsylvania State University, State College 16802, Pennsylvania, USA
| | - Quanxin Qu
- Department of Gynecology and Obstetrics, Tianjin First Central Hospital, Tianjin, China
| | - Xia Zhou
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Illinois, USA
| | - Xiaolan Huang
- Department of Computer Science, Southern Illinois University, Carbondale, Illinois, USA
| | - Zhihua Du
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Illinois, USA
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20
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Calisto F, Sousa FM, Sena FV, Refojo PN, Pereira MM. Mechanisms of Energy Transduction by Charge Translocating Membrane Proteins. Chem Rev 2021; 121:1804-1844. [PMID: 33398986 DOI: 10.1021/acs.chemrev.0c00830] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Life relies on the constant exchange of different forms of energy, i.e., on energy transduction. Therefore, organisms have evolved in a way to be able to harvest the energy made available by external sources (such as light or chemical compounds) and convert these into biological useable energy forms, such as the transmembrane difference of electrochemical potential (Δμ̃). Membrane proteins contribute to the establishment of Δμ̃ by coupling exergonic catalytic reactions to the translocation of charges (electrons/ions) across the membrane. Irrespectively of the energy source and consequent type of reaction, all charge-translocating proteins follow two molecular coupling mechanisms: direct- or indirect-coupling, depending on whether the translocated charge is involved in the driving reaction. In this review, we explore these two coupling mechanisms by thoroughly examining the different types of charge-translocating membrane proteins. For each protein, we analyze the respective reaction thermodynamics, electron transfer/catalytic processes, charge-translocating pathways, and ion/substrate stoichiometries.
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Affiliation(s)
- Filipa Calisto
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, University of Lisboa, Faculty of Sciences, Campo Grande, 1749-016 Lisboa, Portugal
| | - Filipe M Sousa
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, University of Lisboa, Faculty of Sciences, Campo Grande, 1749-016 Lisboa, Portugal
| | - Filipa V Sena
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, University of Lisboa, Faculty of Sciences, Campo Grande, 1749-016 Lisboa, Portugal
| | - Patricia N Refojo
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal
| | - Manuela M Pereira
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157, Oeiras, Portugal.,BioISI-Biosystems & Integrative Sciences Institute, University of Lisboa, Faculty of Sciences, Campo Grande, 1749-016 Lisboa, Portugal
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21
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Singh A, Schnürer A, Westerholm M. Enrichment and description of novel bacteria performing syntrophic propionate oxidation at high ammonia level. Environ Microbiol 2021; 23:1620-1637. [PMID: 33400377 DOI: 10.1111/1462-2920.15388] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 09/15/2020] [Accepted: 01/02/2021] [Indexed: 01/04/2023]
Abstract
Inefficient syntrophic propionate degradation causes severe operating disturbances and reduces biogas productivity in many high-ammonia anaerobic digesters, but propionate-degrading microorganisms in these systems remain unknown. Here, we identified candidate ammonia-tolerant syntrophic propionate-oxidising bacteria using propionate enrichment at high ammonia levels (0.7-0.8 g NH3 L-1 ) in continuously-fed reactors. We reconstructed 30 high-quality metagenome-assembled genomes (MAGs) from the propionate-fed reactors, which revealed two novel species from the families Peptococcaceae and Desulfobulbaceae as syntrophic propionate-oxidising candidates. Both MAGs possess genomic potential for the propionate oxidation and electron transfer required for syntrophic energy conservation and, similar to ammonia-tolerant acetate degrading syntrophs, both MAGs contain genes predicted to link to ammonia and pH tolerance. Based on relative abundance, a Peptococcaceae sp. appeared to be the main propionate degrader and has been given the provisional name "Candidatus Syntrophopropionicum ammoniitolerans". This bacterium was also found in high-ammonia biogas digesters, using quantitative PCR. Acetate was degraded by syntrophic acetate-oxidising bacteria and the hydrogenotrophic methanogenic community consisted of Methanoculleus bourgensis and a yet to be characterised Methanoculleus sp. This work provides knowledge of cooperating syntrophic species in high-ammonia systems and reveals that ammonia-tolerant syntrophic propionate-degrading populations share common features, but diverge genomically and taxonomically from known species.
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Affiliation(s)
- Abhijeet Singh
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, SE-750 07, Sweden
| | - Anna Schnürer
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, SE-750 07, Sweden
| | - Maria Westerholm
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, SE-750 07, Sweden
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22
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Kozlova MI, Bushmakin IM, Belyaeva JD, Shalaeva DN, Dibrova DV, Cherepanov DA, Mulkidjanian AY. Expansion of the "Sodium World" through Evolutionary Time and Taxonomic Space. BIOCHEMISTRY. BIOKHIMIIA 2020; 85:1518-1542. [PMID: 33705291 DOI: 10.1134/s0006297920120056] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In 1986, Vladimir Skulachev and his colleagues coined the term "Sodium World" for the group of diverse organisms with sodium (Na)-based bioenergetics. Albeit only few such organisms had been discovered by that time, the authors insightfully noted that "the great taxonomic variety of organisms employing the Na-cycle points to the ubiquitous distribution of this novel type of membrane-linked energy transductions". Here we used tools of bioinformatics to follow expansion of the Sodium World through the evolutionary time and taxonomic space. We searched for those membrane protein families in prokaryotic genomes that correlate with the use of the Na-potential for ATP synthesis by different organisms. In addition to the known Na-translocators, we found a plethora of uncharacterized protein families; most of them show no homology with studied proteins. In addition, we traced the presence of Na-based energetics in many novel archaeal and bacterial clades, which were recently identified by metagenomic techniques. The data obtained support the view that the Na-based energetics preceded the proton-dependent energetics in evolution and prevailed during the first two billion years of the Earth history before the oxygenation of atmosphere. Hence, the full capacity of Na-based energetics in prokaryotes remains largely unexplored. The Sodium World expanded owing to the acquisition of new functions by Na-translocating systems. Specifically, most classes of G-protein-coupled receptors (GPCRs), which are targeted by almost half of the known drugs, appear to evolve from the Na-translocating microbial rhodopsins. Thereby the GPCRs of class A, with 700 representatives in human genome, retained the Na-binding site in the center of the transmembrane heptahelical bundle together with the capacity of Na-translocation. Mathematical modeling showed that the class A GPCRs could use the energy of transmembrane Na-potential for increasing both their sensitivity and selectivity. Thus, GPCRs, the largest protein family coded by human genome, stem from the Sodium World, which encourages exploration of other Na-dependent enzymes of eukaryotes.
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Affiliation(s)
- M I Kozlova
- School of Physics, Osnabrueck University, Osnabrueck, 49069, Germany. .,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
| | - I M Bushmakin
- School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119992, Russia.
| | - J D Belyaeva
- School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119992, Russia.
| | - D N Shalaeva
- School of Physics, Osnabrueck University, Osnabrueck, 49069, Germany.
| | - D V Dibrova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia.
| | - D A Cherepanov
- Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia.
| | - A Y Mulkidjanian
- School of Physics, Osnabrueck University, Osnabrueck, 49069, Germany. .,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia.,School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119992, Russia
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23
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Pérez-Castiñeira JR, Serrano A. The H +-Translocating Inorganic Pyrophosphatase From Arabidopsis thaliana Is More Sensitive to Sodium Than Its Na +-Translocating Counterpart From Methanosarcina mazei. FRONTIERS IN PLANT SCIENCE 2020; 11:1240. [PMID: 32903538 PMCID: PMC7438732 DOI: 10.3389/fpls.2020.01240] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 07/28/2020] [Indexed: 06/11/2023]
Abstract
Overexpression of membrane-bound K+-dependent H+-translocating inorganic pyrophosphatases (H+-PPases) from higher plants has been widely used to alleviate the sensitivity toward NaCl in these organisms, a strategy that had been previously tested in Saccharomyces cerevisiae. On the other hand, H+-PPases have been reported to functionally complement the yeast cytosolic soluble pyrophosphatase (IPP1). Here, the efficiency of the K+-dependent Na+-PPase from the archaeon Methanosarcina mazei (MVP) to functionally complement IPP1 has been compared to that of its H+-pumping counterpart from Arabidopsis thaliana (AVP1). Both membrane-bound integral PPases (mPPases) supported yeast growth equally well under normal conditions, however, cells expressing MVP grew significantly better than those expressing AVP1 under salt stress. The subcellular distribution of the heterologously-expressed mPPases was crucial in order to observe the phenotypes associated with the complementation. In vitro studies showed that the PPase activity of MVP was less sensitive to Na+ than that of AVP1. Consistently, when yeast cells expressing MVP were grown in the presence of NaCl only a marginal increase in their internal PPi levels was observed with respect to control cells. By contrast, yeast cells that expressed AVP1 had significantly higher levels of this metabolite under the same conditions. The H+-pumping activity of AVP1 was also markedly inhibited by Na+. Our results suggest that mPPases primarily act by hydrolysing the PPi generated in the cytosol when expressed in yeast, and that AVP1 is more susceptible to Na+ inhibition than MVP both in vivo and in vitro. Based on this experimental evidence, we propose Na+-PPases as biotechnological tools to generate salt-tolerant plants.
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Affiliation(s)
| | - Aurelio Serrano
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Sevilla, Spain
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24
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Ashok N, Bauer CE. Evidence of defined temporal expression patterns that lead a gram-negative cell out of dormancy. PLoS Genet 2020; 16:e1008660. [PMID: 32203501 PMCID: PMC7117780 DOI: 10.1371/journal.pgen.1008660] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 04/02/2020] [Accepted: 02/07/2020] [Indexed: 01/02/2023] Open
Abstract
Many bacterial species are capable of forming long-lived dormant cells. The best characterized are heat and desiccation resistant spores produced by many Gram-positive species. Less characterized are dormant cysts produced by several Gram-negative species that are somewhat tolerant to increased temperature and very resistant to desiccation. While there is progress in understanding regulatory circuits that control spore germination, there is scarce information on how Gram-negative organisms emerges from dormancy. In this study, we show that R. centenum cysts germinate by emerging a pair of motile vegetative cells from a thick cyst cell wall coat ~ 6 hrs post induction of germination. Time-lapse transcriptomic analysis reveals that there is a defined temporal pattern of gene expression changes during R. centenum cyst germination. The first observable changes are increases in expression of genes for protein synthesis, an increase in expression of genes involved in the generation of a membrane potential and the use of this potential for ATP synthesis via ATPase expression. These early events are followed by expression changes that affect the cell wall and membrane composition, followed by expression changes that promote chromosome replication. Midway through germination, expression changes occur that promote the flow of carbon through the TCA cycle to generate reducing power and parallel synthesis of electron transfer components involved in oxidative phosphorylation. Finally, late expression changes promote the synthesis of a photosystem as well as flagellar and chemotaxis components for motility.
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Affiliation(s)
- Nandhini Ashok
- Department of Biology, Indiana University, Bloomington, Indiana, United States of America
| | - Carl E. Bauer
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana, United States of America
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25
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Baykov AA. Energy Coupling in Cation-Pumping Pyrophosphatase-Back to Mitchell. FRONTIERS IN PLANT SCIENCE 2020; 11:107. [PMID: 32117404 PMCID: PMC7034417 DOI: 10.3389/fpls.2020.00107] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 01/24/2020] [Indexed: 06/10/2023]
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26
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Holmes AOM, Kalli AC, Goldman A. The Function of Membrane Integral Pyrophosphatases From Whole Organism to Single Molecule. Front Mol Biosci 2019; 6:132. [PMID: 31824962 PMCID: PMC6882861 DOI: 10.3389/fmolb.2019.00132] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/08/2019] [Indexed: 12/02/2022] Open
Abstract
Membrane integral pyrophosphatases (mPPases) are responsible for the hydrolysis of pyrophosphate. This enzymatic mechanism is coupled to the pumping of H+ or Na+ across membranes in a process that can be K+ dependent or independent. Understanding the movements and dynamics throughout the mPPase catalytic cycle is important, as this knowledge is essential for improving or impeding protein function. mPPases have been shown to play a crucial role in plant maturation and abiotic stress tolerance, and so have the potential to be engineered to improve plant survival, with implications for global food security. mPPases are also selectively toxic drug targets, which could be pharmacologically modulated to reduce the virulence of common human pathogens. The last few years have seen the publication of many new insights into the function and structure of mPPases. In particular, there is a new body of evidence that the catalytic cycle is more complex than originally proposed. There are structural and functional data supporting a mechanism involving half-of-the-sites reactivity, inter-subunit communication, and exit channel motions. A more advanced and in-depth understanding of mPPases has begun to be uncovered, leaving the field of research with multiple interesting avenues for further exploration and investigation.
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Affiliation(s)
- Alexandra O. M. Holmes
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Antreas C. Kalli
- Leeds Institute of Cardiovascular and Metabolic Medicine and Astbury Centre for Structural Biology, University of Leeds, Leeds, United Kingdom
| | - Adrian Goldman
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
- Research Program in Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland
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27
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Primo C, Pizzio GA, Yang J, Gaxiola RA, Scholz-Starke J, Hirschi KD. Plant proton pumping pyrophosphatase: the potential for its pyrophosphate synthesis activity to modulate plant growth. PLANT BIOLOGY (STUTTGART, GERMANY) 2019; 21:989-996. [PMID: 31081197 DOI: 10.1111/plb.13007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 05/09/2019] [Indexed: 05/25/2023]
Abstract
Cellular pyrophosphate (PPi) homeostasis is vital for normal plant growth and development. Plant proton-pumping pyrophosphatases (H+ -PPases) are enzymes with different tissue-specific functions related to the regulation of PPi homeostasis. Enhanced expression of plant H+ -PPases increases biomass and yield in different crop species. Here, we emphasise emerging studies utilising heterologous expression in yeast and plant vacuole electrophysiology approaches, as well as phylogenetic relationships and structural analysis, to showcase that the H+ -PPases possess a PPi synthesis function. We postulate this synthase activity contributes to modulating and promoting plant growth both in H+ -PPase-engineered crops and in wild-type plants. We propose a model where the PPi synthase activity of H+ -PPases maintains the PPi pool when cells adopt PPi-dependent glycolysis during high energy demands and/or low oxygen environments. We conclude by proposing experiments to further investigate the H+ -PPase-mediated PPi synthase role in plant growth.
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Affiliation(s)
- C Primo
- Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX, USA
| | - G A Pizzio
- Center for Research in Agricultural Genomics, Consejo Superior de Investigaciones Científicas, Barcelona, Spain
| | - J Yang
- Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX, USA
| | - R A Gaxiola
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - J Scholz-Starke
- Institute of Biophysics, Consiglio Nazionale delle Ricerche, Genova, Italy
| | - K D Hirschi
- Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX, USA
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28
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Schoelmerich MC, Müller V. Energy-converting hydrogenases: the link between H 2 metabolism and energy conservation. Cell Mol Life Sci 2019; 77:1461-1481. [PMID: 31630229 DOI: 10.1007/s00018-019-03329-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/17/2019] [Accepted: 10/01/2019] [Indexed: 10/25/2022]
Abstract
The reversible interconversion of molecular hydrogen and protons is one of the most ancient microbial metabolic reactions and catalyzed by hydrogenases. A widespread yet largely enigmatic group comprises multisubunit [NiFe] hydrogenases, that directly couple H2 metabolism to the electrochemical ion gradient across the membranes of bacteria and of archaea. These complexes are collectively referred to as energy-converting hydrogenases (Ech), as they reversibly transform redox energy into physicochemical energy. Redox energy is typically provided by a low potential electron donor such as reduced ferredoxin to fuel H2 evolution and the establishment of a transmembrane electrochemical ion gradient ([Formula: see text]). The [Formula: see text] is then utilized by an ATP synthase for energy conservation by generating ATP. This review describes the modular structure/function of Ech complexes, focuses on insights into the energy-converting mechanisms, describes the evolutionary context and delves into the implications of relying on an Ech complex as respiratory enzyme for microbial metabolism.
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Affiliation(s)
- Marie Charlotte Schoelmerich
- Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany.,Microbiology and Biotechnology, Institute of Plant Sciences and Microbiology, Universität Hamburg, Ohnhorststr. 18, 22609, Hamburg, Germany
| | - Volker Müller
- Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany.
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29
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Anashkin VA, Aksenova VA, Salminen A, Lahti R, Baykov AA. Cooperativity in catalysis by canonical family II pyrophosphatases. Biochem Biophys Res Commun 2019; 517:266-271. [DOI: 10.1016/j.bbrc.2019.07.056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 07/17/2019] [Indexed: 10/26/2022]
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30
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Serrano-Bueno G, Madroñal JM, Manzano-López J, Muñiz M, Pérez-Castiñeira JR, Hernández A, Serrano A. Nuclear proteasomal degradation of Saccharomyces cerevisiae inorganic pyrophosphatase Ipp1p, a nucleocytoplasmic protein whose stability depends on its subcellular localization. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:1019-1033. [DOI: 10.1016/j.bbamcr.2019.02.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 02/13/2019] [Accepted: 02/26/2019] [Indexed: 12/29/2022]
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31
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Vidilaseris K, Kiriazis A, Turku A, Khattab A, Johansson NG, Leino TO, Kiuru PS, Boije af Gennäs G, Meri S, Yli-Kauhaluoma J, Xhaard H, Goldman A. Asymmetry in catalysis by Thermotoga maritima membrane-bound pyrophosphatase demonstrated by a nonphosphorus allosteric inhibitor. SCIENCE ADVANCES 2019; 5:eaav7574. [PMID: 31131322 PMCID: PMC6530997 DOI: 10.1126/sciadv.aav7574] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 04/16/2019] [Indexed: 06/09/2023]
Abstract
Membrane-bound pyrophosphatases are homodimeric integral membrane proteins that hydrolyze pyrophosphate into orthophosphates, coupled to the active transport of protons or sodium ions across membranes. They are important in the life cycle of bacteria, archaea, plants, and parasitic protists, but no homologous proteins exist in vertebrates, making them a promising drug target. Here, we report the first nonphosphorus allosteric inhibitor of the thermophilic bacterium Thermotoga maritima membrane-bound pyrophosphatase and its bound structure together with the substrate analog imidodiphosphate. The unit cell contains two protein homodimers, each binding a single inhibitor dimer near the exit channel, creating a hydrophobic clamp that inhibits the movement of β-strand 1-2 during pumping, and thus prevents the hydrophobic gate from opening. This asymmetry of inhibitor binding with respect to each homodimer provides the first clear structural demonstration of asymmetry in the catalytic cycle of membrane-bound pyrophosphatases.
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Affiliation(s)
- Keni Vidilaseris
- Research Program in Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland
| | - Alexandros Kiriazis
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Ainoleena Turku
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Ayman Khattab
- Malaria Research Laboratory, Immunobiology Research Program, Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland
| | - Niklas G. Johansson
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Teppo O. Leino
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Paula S. Kiuru
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Gustav Boije af Gennäs
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Seppo Meri
- Malaria Research Laboratory, Immunobiology Research Program, Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland
| | - Jari Yli-Kauhaluoma
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Henri Xhaard
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Adrian Goldman
- Research Program in Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
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32
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Roles of the Hydrophobic Gate and Exit Channel in Vigna radiata Pyrophosphatase Ion Translocation. J Mol Biol 2019; 431:1619-1632. [PMID: 30878480 DOI: 10.1016/j.jmb.2019.03.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/26/2019] [Accepted: 03/03/2019] [Indexed: 12/25/2022]
Abstract
Membrane-embedded pyrophosphatase (M-PPase) hydrolyzes pyrophosphate to drive ion (H+ and/or Na+) translocation. We determined crystal structures and functions of Vigna radiata M-PPase (VrH+-PPase), the VrH+-PPase-2Pi complex and mutants at hydrophobic gate (residue L555) and exit channel (residues T228 and E225). Ion pore diameters along the translocation pathway of three VrH+-PPases complexes (Pi-, 2Pi- and imidodiphosphate-bound states) present a unique wave-like profile, with different pore diameters at the hydrophobic gate and exit channel, indicating that the ligands induced pore size alterations. The 2Pi-bound state with the largest pore diameter might mimic the hydrophobic gate open. In mutant structures, ordered waters detected at the hydrophobic gate among VrH+-PPase imply the possibility of solvation, and numerous waters at the exit channel might signify an open channel. A salt-bridge, E225-R562 is at the way out of the exit channel of VrH+-PPase; E225A mutant makes the interaction eliminated and reveals a decreased pumping ability. E225-R562 might act as a latch to regulate proton release. A water wire from the ion gate (R-D-K-E) through the hydrophobic gate and into the exit channel may reflect the path of proton transfer.
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33
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Timmers PHA, Vavourakis CD, Kleerebezem R, Damsté JSS, Muyzer G, Stams AJM, Sorokin DY, Plugge CM. Metabolism and Occurrence of Methanogenic and Sulfate-Reducing Syntrophic Acetate Oxidizing Communities in Haloalkaline Environments. Front Microbiol 2018; 9:3039. [PMID: 30619130 PMCID: PMC6295475 DOI: 10.3389/fmicb.2018.03039] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 11/26/2018] [Indexed: 01/31/2023] Open
Abstract
Anaerobic syntrophic acetate oxidation (SAO) is a thermodynamically unfavorable process involving a syntrophic acetate oxidizing bacterium (SAOB) that forms interspecies electron carriers (IECs). These IECs are consumed by syntrophic partners, typically hydrogenotrophic methanogenic archaea or sulfate reducing bacteria. In this work, the metabolism and occurrence of SAOB at extremely haloalkaline conditions were investigated, using highly enriched methanogenic (M-SAO) and sulfate-reducing (S-SAO) cultures from south-western Siberian hypersaline soda lakes. Activity tests with the M-SAO and S-SAO cultures and thermodynamic calculations indicated that H2 and formate are important IECs in both SAO cultures. Metagenomic analysis of the M-SAO cultures showed that the dominant SAOB was ‘Candidatus Syntrophonatronum acetioxidans,’ and a near-complete draft genome of this SAOB was reconstructed. ‘Ca. S. acetioxidans’ has all genes necessary for operating the Wood–Ljungdahl pathway, which is likely employed for acetate oxidation. It also encodes several genes essential to thrive at haloalkaline conditions; including a Na+-dependent ATP synthase and marker genes for ‘salt-out‘ strategies for osmotic homeostasis at high soda conditions. Membrane lipid analysis of the M-SAO culture showed the presence of unusual bacterial diether membrane lipids which are presumably beneficial at extreme haloalkaline conditions. To determine the importance of SAO in haloalkaline environments, previously obtained 16S rRNA gene sequencing data and metagenomic data of five different hypersaline soda lake sediment samples were investigated, including the soda lakes where the enrichment cultures originated from. The draft genome of ‘Ca. S. acetioxidans’ showed highest identity with two metagenome-assembled genomes (MAGs) of putative SAOBs that belonged to the highly abundant and diverse Syntrophomonadaceae family present in the soda lake sediments. The 16S rRNA gene amplicon datasets of the soda lake sediments showed a high similarity of reads to ‘Ca. S. acetioxidans’ with abundance as high as 1.3% of all reads, whereas aceticlastic methanogens and acetate oxidizing sulfate-reducers were not abundant (≤0.1%) or could not be detected. These combined results indicate that SAO is the primary anaerobic acetate oxidizing pathway at extreme haloalkaline conditions performed by haloalkaliphilic syntrophic consortia.
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Affiliation(s)
- Peer H A Timmers
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, Netherlands.,European Centre of Excellence for Sustainable Water Technology, Wetsus, Leeuwarden, Netherlands
| | - Charlotte D Vavourakis
- Microbial Systems Ecology, Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
| | - Robbert Kleerebezem
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
| | - Jaap S Sinninghe Damsté
- Department of Marine Microbiology and Biogeochemistry, NIOZ Netherlands Institute for Sea Research, Utrecht University, Utrecht, Netherlands.,Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Utrecht, Netherlands
| | - Gerard Muyzer
- Microbial Systems Ecology, Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
| | - Alfons J M Stams
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, Netherlands.,Centre of Biological Engineering, University of Minho, Braga, Portugal
| | - Dimity Y Sorokin
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands.,Winogradsky Institute of Microbiology, Research Centre of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Caroline M Plugge
- Laboratory of Microbiology, Wageningen University & Research, Wageningen, Netherlands.,European Centre of Excellence for Sustainable Water Technology, Wetsus, Leeuwarden, Netherlands
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34
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Strauss J, Wilkinson C, Vidilaseris K, Harborne SPD, Goldman A. A Simple Strategy to Determine the Dependence of Membrane-Bound Pyrophosphatases on K + as a Cofactor. Methods Enzymol 2018; 607:131-156. [PMID: 30149856 DOI: 10.1016/bs.mie.2018.04.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Membrane-bound pyrophosphatases (mPPases) couple pyrophosphate hydrolysis to H+ and/or Na+ pumping across membranes and are found in all domains of life except for multicellular animals including humans. They are important for development and stress resistance in plants. Furthermore, mPPases play a role in virulence of human pathogens that cause severe diseases such as malaria and African sleeping sickness. Sequence analysis, functional studies, and recently solved crystal structures have contributed to the understanding of the mPPase catalytic cycle. However, several key mechanistic features remain unknown. During evolution, several subgroups of mPPases differing in their pumping specificity and cofactor dependency arose. mPPases are classified into one of five subgroups, usually by sequence analysis. However, classification based solely on sequence has been inaccurate in several instances due to our limited understanding of the molecular mechanism of mPPases. Thus, pumping specificity and cofactor dependency of mPPases require experimental confirmation. Here, we describe a simple method for the determination of K+ dependency in mPPases using a hydrolytic activity assay. By coupling these dependency studies with site-directed mutagenesis, we have begun to build a better understanding of the molecular mechanisms of mPPases. We optimized the assay for thermostable mPPases that are commonly used as model systems in our lab, but the method is equally applicable to mesophilic mPPases with minor modifications.
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Affiliation(s)
- Jannik Strauss
- Astbury Centre for Structural Biology, University of Leeds, Leeds, United Kingdom
| | - Craig Wilkinson
- Astbury Centre for Structural Biology, University of Leeds, Leeds, United Kingdom
| | - Keni Vidilaseris
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Steven P D Harborne
- Astbury Centre for Structural Biology, University of Leeds, Leeds, United Kingdom.
| | - Adrian Goldman
- Astbury Centre for Structural Biology, University of Leeds, Leeds, United Kingdom; Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland.
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35
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Manzoor S, Schnürer A, Bongcam-Rudloff E, Müller B. Genome-Guided Analysis of Clostridium ultunense and Comparative Genomics Reveal Different Strategies for Acetate Oxidation and Energy Conservation in Syntrophic Acetate-Oxidising Bacteria. Genes (Basel) 2018; 9:genes9040225. [PMID: 29690652 PMCID: PMC5924567 DOI: 10.3390/genes9040225] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 04/15/2018] [Accepted: 04/16/2018] [Indexed: 01/04/2023] Open
Abstract
Syntrophic acetate oxidation operates close to the thermodynamic equilibrium and very little is known about the participating organisms and their metabolism. Clostridium ultunense is one of the most abundant syntrophic acetate-oxidising bacteria (SAOB) that are found in engineered biogas processes operating with high ammonia concentrations. It has been proven to oxidise acetate in cooperation with hydrogenotrophic methanogens. There is evidence that the Wood-Ljungdahl (WL) pathway plays an important role in acetate oxidation. In this study, we analysed the physiological and metabolic capacities of C. ultunense strain Esp and strain BST on genome scale and conducted a comparative study of all the known characterised SAOB, namely Syntrophaceticus schinkii, Thermacetogenium phaeum, Tepidanaerobacter acetatoxydans, and Pseudothermotoga lettingae. The results clearly indicated physiological robustness to be beneficial for anaerobic digestion environments and revealed unexpected metabolic diversity with respect to acetate oxidation and energy conservation systems. Unlike S. schinkii and Th. phaeum, C. ultunense clearly does not employ the oxidative WL pathway for acetate oxidation, as its genome (and that of P. lettingae) lack important key genes. In both of those species, a proton motive force is likely formed by chemical protons involving putative electron-bifurcating [Fe-Fe] hydrogenases rather than proton pumps. No genes encoding a respiratory Ech (energy-converting hydrogenase), as involved in energy conservation in Th. phaeum and S. schinkii, were identified in C. ultunense and P. lettingae. Moreover, two respiratory complexes sharing similarities to the proton-translocating ferredoxin:NAD⁺ oxidoreductase (Rnf) and the Na⁺ pumping NADH:quinone hydrogenase (NQR) were predicted. These might form a respiratory chain that is involved in the reduction of electron acceptors rather than protons. However, involvement of these complexes in acetate oxidation in C. ultunense and P. lettingae needs further study. This genome-based comparison provides a solid platform for future meta-proteomics and meta-transcriptomics studies and for metabolic engineering, control, and monitoring of SAOB.
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Affiliation(s)
- Shahid Manzoor
- Department of Information Technology, University of the Punjab, Lahore 54 590, Pakistan.
| | - Anna Schnürer
- BioCenter, Department of Molecular Sciences, Box 7015, Swedish University of Agricultural Sciences, SE 750 07 Uppsala, Sweden.
| | - Erik Bongcam-Rudloff
- SLU-Global Bioinformatics Centre, Department of Animal Breeding and Genetics Science, Swedish University of Agricultural Sciences, SE 750 07 Uppsala, Sweden.
| | - Bettina Müller
- BioCenter, Department of Molecular Sciences, Box 7015, Swedish University of Agricultural Sciences, SE 750 07 Uppsala, Sweden.
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Role of the potassium/lysine cationic center in catalysis and functional asymmetry in membrane-bound pyrophosphatases. Biochem J 2018. [PMID: 29519958 DOI: 10.1042/bcj20180071] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Membrane-bound pyrophosphatases (mPPases), which couple pyrophosphate hydrolysis to transmembrane transport of H+ and/or Na+ ions, are divided into K+,Na+-independent, Na+-regulated, and K+-dependent families. The first two families include H+-transporting mPPases (H+-PPases), whereas the last family comprises one Na+-transporting, two Na+- and H+-transporting subfamilies (Na+-PPases and Na+,H+-PPases, respectively), and three H+-transporting subfamilies. Earlier studies of the few available model mPPases suggested that K+ binds to a site located adjacent to the pyrophosphate-binding site, but is substituted by the ε-amino group of an evolutionarily acquired lysine residue in the K+-independent mPPases. Here, we performed a systematic analysis of the K+/Lys cationic center across all mPPase subfamilies. An Ala → Lys replacement in K+-dependent mPPases abolished the K+ dependence of hydrolysis and transport activities and decreased these activities close to the level (4-7%) observed for wild-type enzymes in the absence of monovalent cations. In contrast, a Lys → Ala replacement in K+,Na+-independent mPPases conferred partial K+ dependence on the enzyme by unmasking an otherwise conserved K+-binding site. Na+ could partially replace K+ as an activator of K+-dependent mPPases and the Lys → Ala variants of K+,Na+-independent mPPases. Finally, we found that all mPPases were inhibited by excess substrate, suggesting strong negative co-operativity of active site functioning in these homodimeric enzymes; moreover, the K+/Lys center was identified as part of the mechanism underlying this effect. These findings suggest that the mPPase homodimer possesses an asymmetry of active site performance that may be an ancient prototype of the rotational binding-change mechanism of F-type ATPases.
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Jongkon N, Gleeson D, Gleeson MP. Elucidation of the catalytic mechanism of 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase using QM/MM calculations. Org Biomol Chem 2018; 16:6239-6249. [DOI: 10.1039/c8ob01428k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This account describes the application of QM/MM calculations to understand the reaction mechanism of HPPK, an important pharmacological target on the folate pathway for the treatment of diseases including anti-microbial resistance, malaria and cancer.
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Affiliation(s)
- Nathjanan Jongkon
- Department of Social and Applied Science
- College of Industrial Technology
- King Mongkut's University of Technology North Bangkok
- Bangkok 10800
- Thailand
| | - Duangkamol Gleeson
- Department of Chemistry
- Faculty of Science
- King Mongkut's Institute of Technology Ladkrabang
- Thailand
| | - M. Paul Gleeson
- Department of Biomedical Engineering
- Faculty of Engineering
- King Mongkut's Institute of Technology Ladkrabang
- Bangkok 10520
- Thailand
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38
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Harborne SPD, Strauss J, Turku A, Watson MA, Tuma R, Harris SA, Goldman A. Defining Dynamics of Membrane-Bound Pyrophosphatases by Experimental and Computational Single-Molecule FRET. Methods Enzymol 2018; 607:93-130. [PMID: 30149870 DOI: 10.1016/bs.mie.2018.04.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Membrane-bound pyrophosphatases couple the hydrolysis of inorganic pyrophosphate to the pumping of ions (sodium or protons) across a membrane in order to generate an electrochemical gradient. This class of membrane protein is widely conserved across plants, fungi, archaea, and bacteria, but absent in multicellular animals, making them a viable target for drug design against protozoan parasites such as Plasmodium falciparum. An excellent understanding of many of the catalytic states throughout the enzymatic cycle has already been afforded by crystallography. However, the dynamics and kinetics of the catalytic cycle between these static snapshots remain to be elucidated. Here, we employ single-molecule Förster resonance energy transfer (FRET) measurements to determine the dynamic range and frequency of conformations available to the enzyme in a lipid bilayer during the catalytic cycle. First, we explore issues related to the introduction of fluorescent dyes by cysteine mutagenesis; we discuss the importance of residue selection for dye attachment, and the balance between mutating areas of the protein that will provide useful dynamics while not altering highly conserved residues that could disrupt protein function. To complement and guide the experiments, we used all-atom molecular dynamics simulations and computational methods to estimate FRET efficiency distributions for dye pairs at different sites in different protein conformational states. We present preliminary single-molecule FRET data that points to insights about the binding modes of different membrane-bound pyrophosphatase substrates and inhibitors.
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Affiliation(s)
- Steven P D Harborne
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Jannik Strauss
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Ainoleena Turku
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Matthew A Watson
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Roman Tuma
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom; Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Sarah A Harris
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Adrian Goldman
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom; Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland.
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Synthesis of Heterologous Mevalonic Acid Pathway Enzymes in Clostridium ljungdahlii for the Conversion of Fructose and of Syngas to Mevalonate and Isoprene. Appl Environ Microbiol 2017; 84:AEM.01723-17. [PMID: 29054870 PMCID: PMC5734045 DOI: 10.1128/aem.01723-17] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 10/15/2017] [Indexed: 11/30/2022] Open
Abstract
There is a growing interest in the use of microbial fermentation for the generation of high-demand, high-purity chemicals using cheap feedstocks in an environmentally friendly manner. One example explored here is the production of isoprene (C5H8), a hemiterpene, which is primarily polymerized to polyisoprene in synthetic rubber in tires but which can also be converted to C10 and C15 biofuels. The strictly anaerobic, acetogenic bacterium Clostridium ljungdahlii, used in all of the work described here, is capable of glycolysis using the Embden-Meyerhof-Parnas pathway and of carbon fixation using the Wood-Ljungdahl pathway. Clostridium-Escherichia coli shuttle plasmids, each bearing either 2 or 3 different heterologous genes of the eukaryotic mevalonic acid (MVA) pathway or eukaryotic isopentenyl pyrophosphate isomerase (Idi) and isoprene synthase (IspS), were constructed and electroporated into C. ljungdahlii. These plasmids, one or two of which were introduced into the host cells, enabled the synthesis of mevalonate and of isoprene from fructose and from syngas (H2, CO2, and CO) and the conversion of mevalonate to isoprene. All of the heterologous enzymes of the MVA pathway, as well as Idi and IspS, were shown to be synthesized at high levels in C. ljungdahlii, as demonstrated by Western blotting, and were enzymatically active, as demonstrated by in vivo product synthesis. The quantities of mevalonate and isoprene produced here are far below what would be required of a commercial production strain. However, proposals are made that could enable a substantial increase in the mass yield of product formation. IMPORTANCE This study demonstrates the ability to synthesize a heterologous metabolic pathway in C. ljungdahlii, an organism capable of metabolizing either simple sugars or syngas or both together (mixotrophy). Syngas, an inexpensive source of carbon and reducing equivalents, is produced as a major component of some industrial waste gas, and it can be generated by gasification of cellulosic biowaste and of municipal solid waste. Its conversion to useful products therefore offers potential cost and environmental benefits. The ability of C. ljungdahlii to grow mixotrophically also enables the recapture, should there be sufficient reducing equivalents available, of the CO2 released upon glycolysis, potentially increasing the mass yield of product formation. Isoprene is the simplest of the terpenoids, and so the demonstration of its production is a first step toward the synthesis of higher-value products of the terpenoid pathway.
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Dibrov P, Dibrov E, Pierce GN. Na+-NQR (Na+-translocating NADH:ubiquinone oxidoreductase) as a novel target for antibiotics. FEMS Microbiol Rev 2017; 41:653-671. [PMID: 28961953 DOI: 10.1093/femsre/fux032] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 05/17/2017] [Indexed: 01/08/2023] Open
Abstract
The recent breakthrough in structural studies on Na+-translocating NADH:ubiquinone oxidoreductase (Na+-NQR) from the human pathogen Vibrio cholerae creates a perspective for the systematic design of inhibitors for this unique enzyme, which is the major Na+ pump in aerobic pathogens. Widespread distribution of Na+-NQR among pathogenic species, its key role in energy metabolism, its relation to virulence in different species as well as its absence in eukaryotic cells makes this enzyme especially attractive as a target for prospective antibiotics. In this review, the major biochemical, physiological and, especially, the pharmacological aspects of Na+-NQR are discussed to assess its 'target potential' for drug development. A comparison to other primary bacterial Na+ pumps supports the contention that NQR is a first rate prospective target for a new generation of antimicrobials. A new, narrowly targeted furanone inhibitor of NQR designed in our group is presented as a molecular platform for the development of anti-NQR remedies.
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Affiliation(s)
- Pavel Dibrov
- Department of Microbiology, University of Manitoba, Winnipeg, Canada
| | - Elena Dibrov
- Institute of Cardiovascular Sciences, Albrechtsen Research Centre, St. Boniface Hospital, Winnipeg, Canada.,Department of Physiology and Pathophysiology, Colleges of Medicine and Pharmacy, Faculty of Health Sciences, Winnipeg, Canada
| | - Grant N Pierce
- Institute of Cardiovascular Sciences, Albrechtsen Research Centre, St. Boniface Hospital, Winnipeg, Canada.,Department of Physiology and Pathophysiology, Colleges of Medicine and Pharmacy, Faculty of Health Sciences, Winnipeg, Canada
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41
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Baykov AA, Anashkin VA, Salminen A, Lahti R. Inorganic pyrophosphatases of Family II-two decades after their discovery. FEBS Lett 2017; 591:3225-3234. [PMID: 28986979 DOI: 10.1002/1873-3468.12877] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 10/04/2017] [Accepted: 10/04/2017] [Indexed: 12/22/2022]
Abstract
Inorganic pyrophosphatases (PPases) convert pyrophosphate (PPi ) to phosphate and are present in all cell types. Soluble PPases belong to three nonhomologous families, of which Family II is found in approximately a quarter of prokaryotic organisms, often pathogenic ones. Each subunit of dimeric canonical Family II PPases is formed by two domains connected by a flexible linker, with the active site located between the domains. These enzymes require both magnesium and a transition metal ion (manganese or cobalt) for maximal activity and are the most active (kcat ≈ 104 s-1 ) among all PPase types. Catalysis by Family II PPases requires four metal ions per substrate molecule, three of which form a unique trimetal center that coordinates the nucleophilic water and converts it to a reactive hydroxide ion. A quarter of Family II PPases contain an autoinhibitory regulatory insert formed by two cystathionine β-synthase (CBS) domains and one DRTGG domain. Adenine nucleotide binding either activates or inhibits the CBS domain-containing PPases, thereby tuning their activity and, hence, PPi levels, in response to changes in cell energy status (ATP/ADP ratio).
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Affiliation(s)
- Alexander A Baykov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Russia
| | - Viktor A Anashkin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Russia
| | - Anu Salminen
- Department of Biochemistry, University of Turku, Finland
| | - Reijo Lahti
- Department of Biochemistry, University of Turku, Finland
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42
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Shen Q, Tan H, Xing GW, Zheng J, Jia Z. A new method to investigate the catalytic mechanism of YhdE pyrophosphatase by using a pyrophosphate fluorescence probe. Sci Rep 2017; 7:8169. [PMID: 28811554 PMCID: PMC5557916 DOI: 10.1038/s41598-017-08368-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 07/11/2017] [Indexed: 01/27/2023] Open
Abstract
YhdE is a Maf (multicopy associated filamentation) proteins from Escherichia coli which exhibits pyrophosphatase activity towards selected nucleotides, although its catalytic mechanism remains unclear. Herein we used a novel fluorescence probe (4-isoACBA–Zn(II) complex) to characterize the enzymatic properties of YhdE and its mutant, establishing a new method for assaying pyrophosphatase catalytic function. Our results reveal for the first time that the new fluorescence sensor confers high sensitivity and specificity and pyrophosphate (PPi) is the direct catalytic product of YhdE. Crystal structures of a mutant in the active-site loop (YhdE_E33A) show conformational flexibility implicated in the catalytic mechanism of YhdE. ITC experiments and computational docking further reveal that Asp70 and substrate dTTP coordinate Mn2+. Quantum mechanics calculations indicate that YhdE hydrolysis appears to follow a stepwise pathway in which a water molecule first attacks the α-phosphorus atom in the substrate, followed by the release of PPi from the pentavalent intermediate.
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Affiliation(s)
- Qingya Shen
- College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Hongwei Tan
- College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Guo-Wen Xing
- College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Jimin Zheng
- College of Chemistry, Beijing Normal University, Beijing, 100875, China.
| | - Zongchao Jia
- Department of Biochemical and Molecular Science, Queen's University, Kingston, Ontario, K7L 3N6, Canada.
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43
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Membrane pyrophosphatases from Thermotoga maritima and Vigna radiata suggest a conserved coupling mechanism. Nat Commun 2016; 7:13596. [PMID: 27922000 PMCID: PMC5150537 DOI: 10.1038/ncomms13596] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 10/18/2016] [Indexed: 11/08/2022] Open
Abstract
Membrane-bound pyrophosphatases (M-PPases), which couple proton/sodium ion transport to pyrophosphate synthesis/hydrolysis, are important in abiotic stress resistance and in the infectivity of protozoan parasites. Here, three M-PPase structures in different catalytic states show that closure of the substrate-binding pocket by helices 5-6 affects helix 13 in the dimer interface and causes helix 12 to move down. This springs a 'molecular mousetrap', repositioning a conserved aspartate and activating the nucleophilic water. Corkscrew motion at helices 6 and 16 rearranges the key ionic gate residues and leads to ion pumping. The pumped ion is above the ion gate in one of the ion-bound structures, but below it in the other. Electrometric measurements show a single-turnover event with a non-hydrolysable inhibitor, supporting our model that ion pumping precedes hydrolysis. We propose a complete catalytic cycle for both proton and sodium-pumping M-PPases, and one that also explains the basis for ion specificity.
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44
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Regmi KC, Pizzio GA, Gaxiola RA. Structural basis for the reversibility of proton pyrophosphatase. PLANT SIGNALING & BEHAVIOR 2016; 11:e1231294. [PMID: 27611445 PMCID: PMC5257167 DOI: 10.1080/15592324.2016.1231294] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Proton Pyrophosphatase (H+-PPase) is an evolutionarily conserved enzyme regarded as a bona fide vacuolar marker. However, H+-PPase also localizes at the plasma membrane of the phloem, where, evidence suggests that it functions as a Pyrophosphate Synthase and participates in phloem loading and photosynthate partitioning. We believe that this pyrophosphate synthesising function of H+-PPase is fundamentally rooted to its molecular structure, and here we postulate, on the basis of published crystal structures of membrane-bound pyrophosphatases, a plausible mechanism of pyrophosphate synthesis.
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Affiliation(s)
- Kamesh C. Regmi
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Gaston A. Pizzio
- Center for Research in Agricultural Genomics, Cerdanyola del Vallès, Barcelona, Spain
| | - Roberto A. Gaxiola
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
- CONTACT Roberto A. Gaxiola
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45
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Two independent evolutionary routes to Na+/H+ cotransport function in membrane pyrophosphatases. Biochem J 2016; 473:3099-111. [DOI: 10.1042/bcj20160529] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 08/03/2016] [Indexed: 11/17/2022]
Abstract
Membrane-bound pyrophosphatases (mPPases) hydrolyze pyrophosphate (PPi) to transport H+, Na+ or both and help organisms to cope with stress conditions, such as high salinity or limiting nutrients. Recent elucidation of mPPase structure and identification of subfamilies that have fully or partially switched from Na+ to H+ pumping have established mPPases as versatile models for studying the principles governing the mechanism, specificity and evolution of cation transporters. In the present study, we constructed an accurate phylogenetic map of the interface of Na+-transporting PPases (Na+-PPases) and Na+- and H+-transporting PPases (Na+,H+-PPases), which guided our experimental exploration of the variations in PPi hydrolysis and ion transport activities during evolution. Surprisingly, we identified two mPPase lineages that independently acquired physiologically significant Na+ and H+ cotransport function. Na+,H+-PPases of the first lineage transport H+ over an extended [Na+] range, but progressively lose H+ transport efficiency at high [Na+]. In contrast, H+-transport by Na+,H+-PPases of the second lineage is not inhibited by up to 100 mM Na+. With the identification of Na+,H+-PPase subtypes, the mPPases protein superfamily appears as a continuum, ranging from monospecific Na+ transporters to transporters with tunable levels of Na+ and H+ cotransport and further to monospecific H+ transporters. Our results lend credence to the concept that Na+ and H+ are transported by similar mechanisms, allowing the relative efficiencies of Na+ and H+ transport to be modulated by minor changes in protein structure during the course of adaptation to a changing environment.
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46
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A highly diverse, desert-like microbial biocenosis on solar panels in a Mediterranean city. Sci Rep 2016; 6:29235. [PMID: 27378552 PMCID: PMC4932501 DOI: 10.1038/srep29235] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/13/2016] [Indexed: 12/03/2022] Open
Abstract
Microorganisms colonize a wide range of natural and artificial environments although there are hardly any data on the microbial ecology of one the most widespread man-made extreme structures: solar panels. Here we show that solar panels in a Mediterranean city (Valencia, Spain) harbor a highly diverse microbial community with more than 500 different species per panel, most of which belong to drought-, heat- and radiation-adapted bacterial genera, and sun-irradiation adapted epiphytic fungi. The taxonomic and functional profiles of this microbial community and the characterization of selected culturable bacteria reveal the existence of a diverse mesophilic microbial community on the panels’ surface. This biocenosis proved to be more similar to the ones inhabiting deserts than to any human or urban microbial ecosystem. This unique microbial community shows different day/night proteomic profiles; it is dominated by reddish pigment- and sphingolipid-producers, and is adapted to withstand circadian cycles of high temperatures, desiccation and solar radiation.
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47
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Marreiros BC, Calisto F, Castro PJ, Duarte AM, Sena FV, Silva AF, Sousa FM, Teixeira M, Refojo PN, Pereira MM. Exploring membrane respiratory chains. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1039-1067. [PMID: 27044012 DOI: 10.1016/j.bbabio.2016.03.028] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/16/2016] [Accepted: 03/18/2016] [Indexed: 01/20/2023]
Abstract
Acquisition of energy is central to life. In addition to the synthesis of ATP, organisms need energy for the establishment and maintenance of a transmembrane difference in electrochemical potential, in order to import and export metabolites or to their motility. The membrane potential is established by a variety of membrane bound respiratory complexes. In this work we explored the diversity of membrane respiratory chains and the presence of the different enzyme complexes in the several phyla of life. We performed taxonomic profiles of the several membrane bound respiratory proteins and complexes evaluating the presence of their respective coding genes in all species deposited in KEGG database. We evaluated 26 quinone reductases, 5 quinol:electron carriers oxidoreductases and 18 terminal electron acceptor reductases. We further included in the analyses enzymes performing redox or decarboxylation driven ion translocation, ATP synthase and transhydrogenase and we also investigated the electron carriers that perform functional connection between the membrane complexes, quinones or soluble proteins. Our results bring a novel, broad and integrated perspective of membrane bound respiratory complexes and thus of the several energetic metabolisms of living systems. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi.
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Affiliation(s)
- Bruno C Marreiros
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
| | - Filipa Calisto
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
| | - Paulo J Castro
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
| | - Afonso M Duarte
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
| | - Filipa V Sena
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
| | - Andreia F Silva
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
| | - Filipe M Sousa
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
| | - Miguel Teixeira
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
| | - Patrícia N Refojo
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
| | - Manuela M Pereira
- Instituto de Tecnologia Química e Biológica-António Xavier, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal.
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48
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Dibrova DV, Galperin MY, Koonin EV, Mulkidjanian AY. Ancient Systems of Sodium/Potassium Homeostasis as Predecessors of Membrane Bioenergetics. BIOCHEMISTRY (MOSCOW) 2016; 80:495-516. [PMID: 26071768 DOI: 10.1134/s0006297915050016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Cell cytoplasm of archaea, bacteria, and eukaryotes contains substantially more potassium than sodium, and potassium cations are specifically required for many key cellular processes, including protein synthesis. This distinct ionic composition and requirements have been attributed to the emergence of the first cells in potassium-rich habitats. Different, albeit complementary, scenarios have been proposed for the primordial potassium-rich environments based on experimental data and theoretical considerations. Specifically, building on the observation that potassium prevails over sodium in the vapor of inland geothermal systems, we have argued that the first cells could emerge in the pools and puddles at the periphery of primordial anoxic geothermal fields, where the elementary composition of the condensed vapor would resemble the internal milieu of modern cells. Marine and freshwater environments generally contain more sodium than potassium. Therefore, to invade such environments, while maintaining excess of potassium over sodium in the cytoplasm, primordial cells needed means to extrude sodium ions. The foray into new, sodium-rich habitats was the likely driving force behind the evolution of diverse redox-, light-, chemically-, or osmotically-dependent sodium export pumps and the increase of membrane tightness. Here we present a scenario that details how the interplay between several, initially independent sodium pumps might have triggered the evolution of sodium-dependent membrane bioenergetics, followed by the separate emergence of the proton-dependent bioenergetics in archaea and bacteria. We also discuss the development of systems that utilize the sodium/potassium gradient across the cell membranes.
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Affiliation(s)
- D V Dibrova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
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R. Shah N, Vidilaseris K, Xhaard H, Goldman A. Integral membrane pyrophosphatases: a novel drug target for human pathogens? AIMS BIOPHYSICS 2016. [DOI: 10.3934/biophy.2016.1.171] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Yang Y, Liu Y, Yuan H, Liu X, Gao Y, Gong M, Zou Z. Membrane-bound pyrophosphatase of human gut microbe Clostridium methylpentosum confers improved salt tolerance in Escherichia coli, Saccharomyces cerevisiae and tobacco. Mol Membr Biol 2016; 33:39-50. [PMID: 29025361 DOI: 10.1080/09687688.2017.1370145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Membrane-bound pyrophosphatases (PPases) are involved in the adaption of organisms to stress conditions, which was substantiated by numerous plant transgenic studies with H+-PPase yet devoid of any correlated evidences for other two subfamilies, Na+-PPase and Na+,H+-PPase. Herein, we demonstrate the gene cloning and functional evaluation of the membrane-bound PPase (CmPP) of the human gut microbe Clostridium methylpentosum. The CmPP gene encodes a single polypeptide of 699 amino acids that was predicted as a multi-spanning membrane and K+-dependent Na+,H+-PPase. Heterologous expression of CmPP could significantly enhance the salt tolerance of both Escherichia coli and Saccharomyces cerevisiae, and this effect in yeast could be fortified by N-terminal addition of a vacuole-targeting signal peptide from the H+-PPase of Trypanosoma cruzi. Furthermore, introduction of CmPP could remarkably improve the salt tolerance of tobacco, implying its potential use in constructing salt-resistant transgenic crops. Consequently, the possible mechanisms of CmPP to underlie salt tolerance are discussed.
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Affiliation(s)
- Yumei Yang
- a School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy , Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University , Kunming , Yunnan , China
| | - Yanjuan Liu
- a School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy , Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University , Kunming , Yunnan , China
| | - Hang Yuan
- a School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy , Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University , Kunming , Yunnan , China
| | - Xian Liu
- a School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy , Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University , Kunming , Yunnan , China
| | - Yanxiu Gao
- a School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy , Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University , Kunming , Yunnan , China
| | - Ming Gong
- a School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy , Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University , Kunming , Yunnan , China
| | - Zhurong Zou
- a School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy , Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University , Kunming , Yunnan , China
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