1
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Duffus BR, Gauglitz M, Teutloff C, Leimkühler S. Redox potentials elucidate the electron transfer pathway of NAD +-dependent formate dehydrogenases. J Inorg Biochem 2024; 253:112487. [PMID: 38306887 DOI: 10.1016/j.jinorgbio.2024.112487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 01/16/2024] [Accepted: 01/16/2024] [Indexed: 02/04/2024]
Abstract
Metal-dependent, nicotine adenine dinucleotide (NAD+)-dependent formate dehydrogenases (FDHs) are complex metalloenzymes coupling biochemical transformations through intricate electron transfer pathways. Rhodobacter capsulatus FDH is a model enzyme for understanding coupled catalysis, in that reversible CO2 reduction and formate oxidation are linked to a flavin mononuclotide (FMN)-bound diaphorase module via seven iron-sulfur (FeS) clusters as a dimer of heterotetramers. Catalysis occurs at a bis-metal-binding pterin (Mo) binding two molybdopterin guanine dinucleotides (bis-MGD), a protein-based Cys residue and a participatory sulfido ligand. Insights regarding the proposed electron transfer mechanism between the bis-MGD and the FMN have been complicated by the discovery that an alternative pathway might occur via intersubunit electron transfer between two [4Fe4S] clusters within electron transfer distance. To clarify this difference, the redox potentials of the bis-MGD and the FeS clusters were determined via redox titration by EPR spectroscopy. Redox potentials for the bis-MGD cofactor and five of the seven FeS clusters could be assigned. Furthermore, substitution of the active site residue Lys295 with Ala resulted in altered enzyme kinetics, primarily due to a more negative redox potential of the A1 [4Fe4S] cluster. Finally, characterization of the monomeric FdsGBAD heterotetramer exhibited slightly decreased formate oxidation activity and similar iron-sulfur clusters reduced relative to the dimeric heterotetramer. Comparison of the measured redox potentials relative to structurally defined FeS clusters support a mechanism by which electron transfer occurs within a heterotetrameric unit, with the interfacial [4Fe4S] cluster serving as a structural component toward the integrity of the heterodimeric structure to drive efficient catalysis.
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Affiliation(s)
- Benjamin R Duffus
- Institute for Biochemistry and Biology, Molecular Enzymology, University of Potsdam, Karl-Liebknecht-Strasse 24-25, 14476 Potsdam, Germany
| | - Marcel Gauglitz
- Institute for Experimental Physics, Free University of Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Christian Teutloff
- Institute for Experimental Physics, Free University of Berlin, Arnimallee 14, 14195 Berlin, Germany.
| | - Silke Leimkühler
- Institute for Biochemistry and Biology, Molecular Enzymology, University of Potsdam, Karl-Liebknecht-Strasse 24-25, 14476 Potsdam, Germany.
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2
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Bennett NK, Lee M, Orr AL, Nakamura K. Systems-level analyses dissociate genetic regulators of reactive oxygen species and energy production. Proc Natl Acad Sci U S A 2024; 121:e2307904121. [PMID: 38207075 PMCID: PMC10801874 DOI: 10.1073/pnas.2307904121] [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: 05/24/2023] [Accepted: 11/20/2023] [Indexed: 01/13/2024] Open
Abstract
Respiratory chain dysfunction can decrease ATP and increase reactive oxygen species (ROS) levels. Despite the importance of these metabolic parameters to a wide range of cellular functions and disease, we lack an integrated understanding of how they are differentially regulated. To address this question, we adapted a CRISPRi- and FACS-based platform to compare the effects of respiratory gene knockdown on ROS to their effects on ATP. Focusing on genes whose knockdown is known to decrease mitochondria-derived ATP, we showed that knockdown of genes in specific respiratory chain complexes (I, III, and CoQ10 biosynthesis) increased ROS, whereas knockdown of other low ATP hits either had no impact (mitochondrial ribosomal proteins) or actually decreased ROS (complex IV). Moreover, although shifting metabolic conditions profoundly altered mitochondria-derived ATP levels, it had little impact on mitochondrial or cytosolic ROS. In addition, knockdown of a subset of complex I subunits-including NDUFA8, NDUFB4, and NDUFS8-decreased complex I activity, mitochondria-derived ATP, and supercomplex level, but knockdown of these genes had differential effects on ROS. Conversely, we found an essential role for ether lipids in the dynamic regulation of mitochondrial ROS levels independent of ATP. Thus, our results identify specific metabolic regulators of cellular ATP and ROS balance that may help dissect the roles of these processes in disease and identify therapeutic strategies to independently target energy failure and oxidative stress.
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Affiliation(s)
- Neal K. Bennett
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA94158
| | - Megan Lee
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA94158
- Aligning Science Across Parkinson’s Collaborative Research Network, Chevy Chase, MD20815
| | - Adam L. Orr
- Appel Alzheimer's Disease Research Institute, Weill Cornell Medicine, New York, NY10021
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY10021
| | - Ken Nakamura
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA94158
- Aligning Science Across Parkinson’s Collaborative Research Network, Chevy Chase, MD20815
- Graduate Program in Biomedical Sciences, University of California, San Francisco, CA94143
- Graduate Program in Neuroscience, University of California San Francisco, San Francisco, CA94158
- Department of Neurology, University of California, San Francisco, CA94158
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3
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Kretzmer C, Reger K, Balassi V, Pham QL, Johns M, Peters ST, Petersen A, Mahadevan J, Gustin J, Borgschulte T, Razafsky D. Chemical and Genetic Modulation of Complex I of the Electron Transport Chain Enhances the Biotherapeutic Protein Production Capacity of CHO Cells. Cells 2023; 12:2661. [PMID: 37998396 PMCID: PMC10670226 DOI: 10.3390/cells12222661] [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: 09/22/2023] [Revised: 10/30/2023] [Accepted: 11/13/2023] [Indexed: 11/25/2023] Open
Abstract
Chinese hamster ovary (CHO) cells are the cell line of choice for producing recombinant therapeutic proteins. Despite improvements in production processes, reducing manufacturing costs remains a key driver in the search for more productive clones. To identify media additives capable of increasing protein production, CHOZN® GS-/- cell lines were screened with 1280 small molecules, and two were identified, forskolin and BrdU, which increased productivity by ≥40%. While it is possible to incorporate these small molecules into a commercial-scale process, doing so may not be financially feasible or could raise regulatory concerns related to the purity of the final drug substance. To circumvent these issues, RNA-Seq was performed to identify transcripts which were up- or downregulated upon BrdU treatment. Subsequent Reactome pathway analysis identified the electron transport chain as an affected pathway. CRISPR/Cas9 was utilized to create missense mutations in two independent components of the electron transport chain and the resultant clones partially recapitulated the phenotypes observed upon BrdU treatment, including the productivity of recombinant therapeutic proteins. Together, this work suggests that BrdU can enhance the productivity of CHO cells by modulating cellular energetics and provides a blueprint for translating data from small molecule chemical screens into genetic engineering targets to improve the performance of CHO cells. This could ultimately lead to more productive host cell lines and a more cost-effective method of supplying medication to patients.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - David Razafsky
- Upstream Research and Development, MilliporeSigma, Saint Louis, MO 63103, USA (A.P.); (J.G.); (T.B.)
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4
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Bennett NK, Lee M, Orr AL, Nakamura K. Systems-level analyses dissociate genetic regulators of reactive oxygen species and energy production. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.14.562276. [PMID: 37904938 PMCID: PMC10614765 DOI: 10.1101/2023.10.14.562276] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2023]
Abstract
Respiratory chain dysfunction can decrease ATP and increase reactive oxygen species (ROS) levels. Despite the importance of these metabolic parameters to a wide range of cellular functions and disease, we lack an integrated understanding of how they are differentially regulated. To address this question, we adapted a CRISPRi- and FACS- based platform to compare the effects of respiratory gene knockdown on ROS to their effects on ATP. Focusing on genes whose knockdown is known to decrease mitochondria-derived ATP, we showed that knockdown of genes in specific respiratory chain complexes (I, III and CoQ10 biosynthesis) increased ROS, whereas knockdown of other low ATP hits either had no impact (mitochondrial ribosomal proteins) or actually decreased ROS (complex IV). Moreover, although shifting metabolic conditions profoundly altered mitochondria-derived ATP levels, it had little impact on mitochondrial or cytosolic ROS. In addition, knockdown of a subset of complex I subunits-including NDUFA8, NDUFB4, and NDUFS8-decreased complex I activity, mitochondria-derived ATP and supercomplex level, but knockdown of these genes had differential effects on ROS. Conversely, we found an essential role for ether lipids in the dynamic regulation of mitochondrial ROS levels independent of ATP. Thus, our results identify specific metabolic regulators of cellular ATP and ROS balance that may help dissect the roles of these processes in disease and identify therapeutic strategies to independently target energy failure and oxidative stress.
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Affiliation(s)
- Neal K. Bennett
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA, 94158, USA
| | - Megan Lee
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA, 94158, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815
| | - Adam L. Orr
- Appel Alzheimer’s Disease Research Institute, Weill Cornell Medicine, New York, NY, USA
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Ken Nakamura
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA, 94158, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815
- Graduate Programs in Neuroscience and Biomedical Sciences, University of California San Francisco, San Francisco, California, USA
- Department of Neurology, University of California, San Francisco, San Francisco, California, 94158, USA
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5
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Gurhan H, Barnes F. Impact of weak radiofrequency and static magnetic fields on key signaling molecules, intracellular pH, membrane potential, and cell growth in HT-1080 fibrosarcoma cells. Sci Rep 2023; 13:14223. [PMID: 37648766 PMCID: PMC10469173 DOI: 10.1038/s41598-023-41167-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 08/23/2023] [Indexed: 09/01/2023] Open
Abstract
There are substantial concerns that extended exposures to weak radiofrequency (RF) fields can lead to adverse health effects. In this study, HT-1080 fibrosarcoma cells were simultaneously exposed to a static magnetic flux density between 10 [Formula: see text] and 300 [Formula: see text] and RF magnetic fields with amplitudes ranging from 1 nT to 1.5 μT in the frequency range from 1.8 to 7.2 MHz for four days. Cell growth rates, intracellular pH, hydrogen peroxide, peroxynitrite, membrane potential and mitochondrial calcium were measured. Results were dependent on carrier frequency and the magnitude of the RF magnetic field, modulation frequencies and the background static magnetic field (SMF). Iron sulphur (Fe-S) clusters are essential for the generation of reactive oxygen species and reactive nitrogen species (ROS and RNS). We believe the observed changes are associated with hyperfine couplings between the chemically active electrons and nuclear spins. Controlling external magnetic fields may have important clinical implications on aging, cancer, arthritis, and Alzheimer's.
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Affiliation(s)
- Hakki Gurhan
- Department of Electrical, Computer and Energy Engineering, University of Colorado at Boulder, 425 UCB #1B55, Boulder, CO, 80309, USA.
| | - Frank Barnes
- Department of Electrical, Computer and Energy Engineering, University of Colorado at Boulder, 425 UCB #1B55, Boulder, CO, 80309, USA
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6
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Khomyakova MA, Merkel AY, Mamiy DD, Klyukina AA, Slobodkin AI. Phenotypic and genomic characterization of Bathyarchaeum tardum gen. nov., sp. nov., a cultivated representative of the archaeal class Bathyarchaeia. Front Microbiol 2023; 14:1214631. [PMID: 37675420 PMCID: PMC10477458 DOI: 10.3389/fmicb.2023.1214631] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 07/31/2023] [Indexed: 09/08/2023] Open
Abstract
Bathyarchaeia are widespread in various anoxic ecosystems and are considered one of the most abundant microbial groups on the earth. There are only a few reports of laboratory cultivation of Bathyarchaeia, and none of the representatives of this class has been isolated in pure culture. Here, we report a sustainable cultivation of the Bathyarchaeia archaeon (strain M17CTs) enriched from anaerobic sediment of a coastal lake. The cells of strain M17CTs were small non-motile cocci, 0.4-0.7 μm in diameter. The cytoplasmic membrane was surrounded by an S-layer and covered with an outermost electron-dense sheath. Strain M17CTs is strictly anaerobic mesophile. It grows at 10-45°C (optimum 37°C), at pH 6.0-10.0 (optimum 8.0), and at NaCl concentrations of 0-60 g l-1 (optimum 20 g l-1). Growth occurred in the presence of methoxylated aromatic compounds (3,4-dimethoxybenzoate and vanillate) together with complex proteinaceous substrates. Dimethyl sulfoxide and nitrate stimulated growth. The phylogenomic analysis placed strain M17CTs to BIN-L-1 genus-level lineage from the BA1 family-level lineage and B26-1 order-level lineage (former subgroup-8) within the class Bathyarchaeia. The complete genome of strain M17CTs had a size of 2.15 Mb with a DNA G + C content of 38.1%. Based on phylogenomic position and phenotypic and genomic properties, we propose to assign strain M17CTs to a new species of a novel genus Bathyarchaeum tardum gen. nov., sp. nov. within the class Bathyarchaeia. This is the first sustainably cultivated representative of Bathyarchaeia. We propose under SeqCode the complete genome sequence of strain M17CTs (CP122380) as a nomenclatural type of Bathyarchaeum tardum, which should be considered as a type for the genus Bathyarchaeum, which is proposed as a type for the family Bathyarchaeaceae, order Bathyarchaeales, and of the class Bathyarchaeia.
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Affiliation(s)
- Maria A. Khomyakova
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander Y. Merkel
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Dana D. Mamiy
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Alexandra A. Klyukina
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander I. Slobodkin
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
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7
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Thompson J, Barr C, Babcock-Adams L, Bird L, La Cava E, Garber A, Hongoh Y, Liu M, Nealson KH, Okamoto A, Repeta D, Suzuki S, Tacto C, Tashjian M, Merino N. Insights into the physiological and genomic characterization of three bacterial isolates from a highly alkaline, terrestrial serpentinizing system. Front Microbiol 2023; 14:1179857. [PMID: 37520355 PMCID: PMC10373932 DOI: 10.3389/fmicb.2023.1179857] [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: 03/05/2023] [Accepted: 05/23/2023] [Indexed: 08/01/2023] Open
Abstract
The terrestrial serpentinite-hosted ecosystem known as "The Cedars" is home to a diverse microbial community persisting under highly alkaline (pH ~ 12) and reducing (Eh < -550 mV) conditions. This extreme environment presents particular difficulties for microbial life, and efforts to isolate microorganisms from The Cedars over the past decade have remained challenging. Herein, we report the initial physiological assessment and/or full genomic characterization of three isolates: Paenibacillus sp. Cedars ('Paeni-Cedars'), Alishewanella sp. BS5-314 ('Ali-BS5-314'), and Anaerobacillus sp. CMMVII ('Anaero-CMMVII'). Paeni-Cedars is a Gram-positive, rod-shaped, mesophilic facultative anaerobe that grows between pH 7-10 (minimum pH tested was 7), temperatures 20-40°C, and 0-3% NaCl concentration. The addition of 10-20 mM CaCl2 enhanced growth, and iron reduction was observed in the following order, 2-line ferrihydrite > magnetite > serpentinite ~ chromite ~ hematite. Genome analysis identified genes for flavin-mediated iron reduction and synthesis of a bacillibactin-like, catechol-type siderophore. Ali-BS5-314 is a Gram-negative, rod-shaped, mesophilic, facultative anaerobic alkaliphile that grows between pH 10-12 and temperatures 10-40°C, with limited growth observed 1-5% NaCl. Nitrate is used as a terminal electron acceptor under anaerobic conditions, which was corroborated by genome analysis. The Ali-BS5-314 genome also includes genes for benzoate-like compound metabolism. Anaero-CMMVII remained difficult to cultivate for physiological studies; however, growth was observed between pH 9-12, with the addition of 0.01-1% yeast extract. Anaero-CMMVII is a probable oxygen-tolerant anaerobic alkaliphile with hydrogenotrophic respiration coupled with nitrate reduction, as determined by genome analysis. Based on single-copy genes, ANI, AAI and dDDH analyses, Paeni-Cedars and Ali-BS5-314 are related to other species (P. glucanolyticus and A. aestuarii, respectively), and Anaero-CMMVII represents a new species. The characterization of these three isolates demonstrate the range of ecophysiological adaptations and metabolisms present in serpentinite-hosted ecosystems, including mineral reduction, alkaliphily, and siderophore production.
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Affiliation(s)
- Jaclyn Thompson
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Casey Barr
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Lydia Babcock-Adams
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Lina Bird
- Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC, United States
| | - Eugenio La Cava
- National Institute for Materials Science, Tsukuba, Ibaraki, Japan
| | - Arkadiy Garber
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
- Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ, United States
| | - Yuichi Hongoh
- School of Life Science and Technology, Tokyo Institute of Technology, Tokyo, Japan
| | - Mark Liu
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Kenneth H. Nealson
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Akihiro Okamoto
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science, Tsukuba, Japan
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido, Japan
- Graduate School of Science and Technology, University of Tsukuba, Tsukuba, Japan
| | - Daniel Repeta
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Shino Suzuki
- Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Sagamihara, Kanagawa, Japan
- Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), JAMSTEC, Yokosuka, Kanagawa, Japan
| | - Clarissa Tacto
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Michelle Tashjian
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Nancy Merino
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, United States
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8
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Perouansky M, Johnson-Schlitz D, Sedensky MM, Morgan PG. A primordial target: Mitochondria mediate both primary and collateral anesthetic effects of volatile anesthetics. Exp Biol Med (Maywood) 2023; 248:545-552. [PMID: 37208922 PMCID: PMC10350799 DOI: 10.1177/15353702231165025] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2023] Open
Abstract
One of the unsolved mysteries of medicine is how do volatile anesthetics (VAs) cause a patient to reversibly lose consciousness. In addition, identifying mechanisms for the collateral effects of VAs, including anesthetic-induced neurotoxicity (AiN) and anesthetic preconditioning (AP), has proven challenging. Multiple classes of molecules (lipids, proteins, and water) have been considered as potential VA targets, but recently proteins have received the most attention. Studies targeting neuronal receptors or ion channels had limited success in identifying the critical targets of VAs mediating either the phenotype of "anesthesia" or their collateral effects. Recent studies in both nematodes and fruit flies may provide a paradigm shift by suggesting that mitochondria may harbor the upstream molecular switch activating both primary and collateral effects. The disruption of a specific step of electron transfer within the mitochondrion causes hypersensitivity to VAs, from nematodes to Drosophila and to humans, while also modulating the sensitivity to collateral effects. The downstream effects from mitochondrial inhibition are potentially legion, but inhibition of presynaptic neurotransmitter cycling appears to be specifically sensitive to the mitochondrial effects. These findings are perhaps of even broader interest since two recent reports indicate that mitochondrial damage may well underlie neurotoxic and neuroprotective effects of VAs in the central nervous system (CNS). It is, therefore, important to understand how anesthetics interact with mitochondria to affect CNS function, not just for the desired facets of general anesthesia but also for significant collateral effects, both harmful and beneficial. A tantalizing possibility exists that both the primary (anesthesia) and secondary (AiN, AP) mechanisms may at least partially overlap in the mitochondrial electron transport chain (ETC).
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Affiliation(s)
- Misha Perouansky
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53792, USA
- Laboratory of Genetics, School of Medicine and Public Health and College of Agricultural and Life Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Dena Johnson-Schlitz
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53792, USA
| | - Margaret M Sedensky
- Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine, Seattle, WA 98101, USA
| | - Philip G Morgan
- Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine, Seattle, WA 98101, USA
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Khomyakova MA, Zavarzina DG, Merkel AY, Klyukina AA, Pikhtereva VA, Gavrilov SN, Slobodkin AI. The first cultivated representatives of the actinobacterial lineage OPB41 isolated from subsurface environments constitute a novel order Anaerosomatales. Front Microbiol 2022; 13:1047580. [PMID: 36439822 PMCID: PMC9686372 DOI: 10.3389/fmicb.2022.1047580] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 10/24/2022] [Indexed: 08/01/2023] Open
Abstract
The continental subsurface harbors microbial populations highly enriched in uncultured taxa. OPB41 is an uncultured order-level phylogenetic lineage within the actinobacterial class Coriobacteriia. OPB41 bacteria have a wide geographical distribution, but the physiology and metabolic traits of this cosmopolitan group remain elusive. From two contrasting subsurface environments, a terrestrial mud volcano and a deep subsurface aquifer, located in the central part of Eurasia, within the Caucasus petroleum region, we have isolated two pure cultures of anaerobic actinobacteria belonging to OPB41. The cells of both strains are small non-motile rods forming numerous pili-like appendages. Strain M08DHBT is mesophilic, while strain Es71-Z0120T is a true thermophile having a broad temperature range for growth (25-77°C). Strain M08DHBT anaerobically reduces sulfur compounds and utilizes an aromatic compound 3,4-dihydroxybenzoic acid. Strain Es71-Z0120T is an obligate dissimilatory Fe(III) reducer that is unable to utilize aromatic compounds. Both isolates grow lithotrophically and consume molecular hydrogen or formate using either thiosulfate, elemental sulfur, or Fe(III) as an electron acceptor. Genomes of the strains encode the putative reductive glycine pathway for autotrophic CO2 fixation, Ni-Fe hydrogenases, putative thiosulfate/polysulfide reductases, and multiheme c-type cytochromes presumably involved in dissimilatory Fe(III) reduction. We propose to assign the isolated strains to the novel taxa of the species-order levels and describe strain M08DHBT as Anaerosoma tenue gen. nov., sp. nov., and strain Es71-Z0120T as Parvivirga hydrogeniphila gen. nov., sp. nov., being members of Anaerosomatales ord. nov. This work expands the knowledge of the diversity, metabolic functions, and ecological role of the phylum Actinomycetota.
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Affiliation(s)
- Maria A. Khomyakova
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Daria G. Zavarzina
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander Y. Merkel
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexandra A. Klyukina
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Valeria A. Pikhtereva
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Sergey N. Gavrilov
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander I. Slobodkin
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
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10
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How to Use Respiratory Chain Inhibitors in Toxicology Studies-Whole-Cell Measurements. Int J Mol Sci 2022; 23:ijms23169076. [PMID: 36012337 PMCID: PMC9409450 DOI: 10.3390/ijms23169076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 08/01/2022] [Accepted: 08/08/2022] [Indexed: 11/16/2022] Open
Abstract
Mitochondrial electron transport chain (ETC) inhibition is a phenomenon interesting in itself and serves as a tool for studying various cellular processes. Despite the fact that searching the term “rotenone” in PubMed returns more than 6900 results, there are many discrepancies regarding the directions of changes reported to be caused by this RTC inhibitor in the delicate redox balance of the cell. Here, we performed a multifaceted study of the popular ETC inhibitors rotenone and antimycin A, involving assessment of mitochondrial membrane potential and the production of hydrogen peroxide and superoxide anions at cellular and mitochondrial levels over a wide range of inhibitor concentrations (1 nmol/dm3–100 µmol/dm3). All measurements were performed with whole cells, with accompanying control of ATP levels. Antimycin A was more potent in hindering HepG2 cells’ abilities to produce ATP, decreasing ATP levels even at a 1 nmol/dm3 concentration, while in the case of rotenone, a 10,000-times greater concentration was needed to produce a statistically significant decrease. The amount of hydrogen peroxide produced in the course of antimycin A biological activity increased rapidly at low concentrations and decreased below control level at a high concentration of 100 µmol/dm3. While both inhibitors influenced cellular superoxide anion production in a comparable manner, rotenone caused a greater increase in mitochondrial superoxide anions compared to a modest impact for antimycin A. IC50 values for rotenone and antimycin A with respect to HepG2 cell survival were of the same order of magnitude, but the survival curve of cells treated with rotenone was clearly biphasic, suggesting a concentration-dependent mode of biological action. We propose a clear experimental setup allowing for complete and credible analysis of the redox state of cells under stress conditions which allows for better understanding of the effects of ETC inhibition.
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11
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Begmatov S, Beletsky AV, Dedysh SN, Mardanov AV, Ravin NV. Genome analysis of the candidate phylum MBNT15 bacterium from a boreal peatland predicted its respiratory versatility and dissimilatory iron metabolism. Front Microbiol 2022; 13:951761. [PMID: 35992725 PMCID: PMC9386147 DOI: 10.3389/fmicb.2022.951761] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 07/19/2022] [Indexed: 11/13/2022] Open
Abstract
Uncultured bacteria of the candidate phylum MBNT15, distantly related to Desulfobacterota, have been identified in a broad range of mostly organic-rich aquatic environments. We assembled a near-complete genome of a member of MBNT15 from a boreal peatland metagenome and used genomic data to analyze the metabolic pathways of this bacterium and its ecological role. This bacterium, designated SHF-111, was predicted to be rod shaped, it lacks flagellar machinery but twitching motility is encoded. Genome-based phylogenetic analysis supported the phylum-level classification of the MBNT15 lineage. Genome annotation and metabolic reconstruction revealed the presence of the Embden-Meyerhof, Entner-Doudoroff and pentose phosphate pathways, as well as the complete tricarboxylic acid (TCA) cycle, and suggested a facultatively anaerobic chemoheterotrophic lifestyle with the ability to ferment peptides, amino acids, fatty acids and simple sugars, and completely oxidize these substrates through aerobic and anaerobic respiration. The SHF-111 genome encodes multiple multiheme c-type cytochromes that probably enable dissimilatory iron reduction. Consistently, the relative abundance of MBNT15 in peatlands positively correlated with iron concentration. Apparently, in the wetland ecosystem, MBNT15 representatives play the role of scavengers, carrying out the complete mineralization of low molecular weight organic substances formed as a result of microbial degradation of complex polymeric substrates. Comparative genome analysis of the MBNT15 phylum revealed that vast majority of its members are capable of aerobic respiration and dissimilatory iron reduction and some species also can reduce sulfur and nitrogen compounds, but not sulfate. Based on phylogenetic and genomic analyses, the novel bacterium is proposed to be classified as Candidatus Deferrimicrobium borealis, within a candidate phylum Deferrimicrobiota.
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Affiliation(s)
- Shahjahon Begmatov
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Alexey V. Beletsky
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Svetlana N. Dedysh
- Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Andrey V. Mardanov
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Nikolai V. Ravin
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
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12
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Role of the Gene ndufs8 Located in Respiratory Complex I from Monascus purpureus in the Cell Growth and Secondary Metabolites Biosynthesis. J Fungi (Basel) 2022; 8:jof8070655. [PMID: 35887413 PMCID: PMC9319538 DOI: 10.3390/jof8070655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 06/19/2022] [Accepted: 06/21/2022] [Indexed: 02/04/2023] Open
Abstract
Our previous work revealed that the anabolism of Monascus secondary metabolites is closely related to cofactor metabolism. In this study, we have further investigated the regulation mechanisms of respiratory complex I in response to the cell growth and secondary metabolite biosynthesis of M. purpureus. The results showed that downregulating the mRNA level of gene ndufs8 in M. purpureus sharply increased the secondary metabolites biosynthesis, cell growth and glucose consumption rates at the fermentation metaphase; slightly increased the colony diameter and biomass, and dramatically changed the mycelia morphology; and decreased the tolerances to environmental factors (especially H2O2). It also significantly inhibited the enzymes activities of respiratory complex I, III and superoxide dismutase, but stimulated that of complex II, IV and peroxidase, leading to an increase in reactive oxygen species (ROS) level and a decrease in ATP concentration. Furthermore, transcriptome analysis revealed that the mRNA levels of genes involved in respiratory chain, tricarboxylic acid cycle, and fatty acid degradation were downregulated, but those in the citrinin and monascus pigment biosynthesis and related pathways were upregulated. These data revealed that complex I plays a vital role in regulating the cell growth and secondary metabolism of Monascus via changing the intracellular ROS and ATP levels.
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13
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Baeshen M, Alkaladi A, Alhejen A, Bataweel N, Abdelkader H, Suliman abuzahrah S. Exploring the Taxonomic and Functional Diversity of Marine Benthic Micro-Eukaryotes Along the Red Sea Coast of Jeddah City. Saudi J Biol Sci 2022; 29:103342. [PMID: 35846388 PMCID: PMC9278075 DOI: 10.1016/j.sjbs.2022.103342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 05/07/2022] [Accepted: 06/10/2022] [Indexed: 11/16/2022] Open
Abstract
Backgrounds Diverse marine habitats along Jeddah's Red Sea coast support rich biodiversity. Few studies have been done on its diverse communities, especially its microbial counterparts. Metagenomic analysis of marine benthic micro-eukaryotic communities was performed for the first time on the Red Sea coast of Jeddah. This research looks into their community structure and metabolic potential. Methods Next-generation sequencing was used to examine the micro-eukaryotic communities of seven sedimentary soil samples from four Jeddah coast locations. After isolating DNA from seven benthic sedimentary soil samples, the 18S rDNA V4 regions were amplified and sequenced on the Illumina MiSeq. It was also verified using an Agilent Technologies 2100 Bioanalyzer with a DNA 1000 chip (Agilent Technologies, Fisher Scientific). A standard curve of fluorescence readings generated by qPCR quantification using the Illumina library was achieved using the GS FLX library. Metagenomic data analysis was used to evaluate the microbial communities' biochemical and enzymatic allocations in studied samples. Results Blast analysis showed that the top ten phyla were Annelida, Eukaryota, Diatomea, Porifera, Phragmoplastophyta, Arthropoda, Dinoflagellata, Xenacoelomorpha Nematoda, and uncultured. Annelida was also found in the highest percentage (93%), in the sample M followed by Porifera (64%), the most abundant in the control sample then Eukaryotes (61%), Phragmatoplastophyta (55%), Arthropoda, and Diatomea (the least common) (32%). community diversity analysis: using Shannon and inverse Simpson indices showed sediment composition to be effective. Also, PICRUST2 indicated that the most abundant pathways were pyruvate fermentation to isobutanol, pyrimidine deoxyribonucleotide phosphorylation, adenosine ribonucleotide de novo biosynthesis, guanosine ribonucleotide de novo biosynthesis, NAD salvage pathway I, the super pathway of glyoxylate bypass and aerobic respiration I (cytochrome c). Conclusion Results showed that high throughput metagenomics could reveal species diversity and estimate gene profiles. Environmental factors appear to be more important than geographic variation in determining the structure of these microbial communities. This study provides the first report of marine benthic micro-eukaryotic communities found on the Red Sea coast of Jeddah and will serve as a good platform for future research.
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14
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Pang Y, Zhang C, Gao J. Macrophages as Emerging Key Players in Mitochondrial Transfers. Front Cell Dev Biol 2021; 9:747377. [PMID: 34722528 PMCID: PMC8548694 DOI: 10.3389/fcell.2021.747377] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 09/21/2021] [Indexed: 12/15/2022] Open
Abstract
Macrophages are a group of heterogeneous cells widely present throughout the body. Under the influence of their specific environments, via both contact and noncontact signals, macrophages integrate into host tissues and contribute to their development and the functions of their constituent cells. Mitochondria are essential organelles that perform intercellular transfers to regulate cell homeostasis. Our review focuses on newly discovered roles of mitochondrial transfers between macrophages and surrounding cells and summarizes emerging functions of macrophages in transmitophagy, metabolic regulation, and immune defense. We also discuss the negative influence of mitochondrial transfers on macrophages, as well as current therapies targeting mitochondria in macrophages. Regulation of macrophages through mitochondrial transfers between macrophages and their surrounding cells is a promising therapy for various diseases, including cardiovascular diseases, inflammatory diseases, obesity, and cancer.
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Affiliation(s)
| | - Changqing Zhang
- Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Junjie Gao
- Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
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15
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Poor Person's pH Simulation of Membrane Proteins. Methods Mol Biol 2021. [PMID: 34302678 DOI: 10.1007/978-1-0716-1468-6_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
pH conditions are central to the functioning of all biomolecules. However, implications of pH changes are nontrivial on a molecular scale. Though a rigorous microscopic definition of pH exists, its implementation in classical molecular dynamics (MD) simulations is cumbersome, and more so in large integral membrane systems. In this chapter, an integrative pipeline is described that combines Multi-Conformation Continuum Electrostatics (MCCE) computations with MD simulations to capture the effect of transient protonation states on the coupled conformational changes in transmembrane proteins. The core methodologies are explained, and all the software required to set up this pipeline are outlined with their key parameters. All associated analyses of structure and function are provided using two case studies, namely those of bioenergetic complexes: NADH dehydrogenase (complex I) and Vo domain of V-type ATPase. The hybrid MCCE-MD pipeline has allowed the discovery of hydrogen bond networks, ligand binding pathways, and disease-causing mutations.
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16
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Mugengana AK, Vita NA, Brown Gandt A, Moran K, Agyapong G, Sharma LK, Griffith EC, Liu J, Yang L, Gavrish E, Hevener KE, LaFleur MD, Lee RE. The Discovery and Development of Thienopyrimidines as Inhibitors of Helicobacter pylori That Act through Inhibition of the Respiratory Complex I. ACS Infect Dis 2021; 7:1044-1058. [PMID: 33471519 DOI: 10.1021/acsinfecdis.0c00300] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The successful treatment of Helicobacter pylori infections is becoming increasingly difficult due to the rise of resistance against current broad spectrum triple therapy regimens. In the search for narrow-spectrum agents against H. pylori, a high-throughput screen identified two structurally related thienopyrimidine compounds that selectively inhibited H. pylori over commensal members of the gut microbiota. To develop the structure-activity relationship (SAR) of the thienopyrimidines against H. pylori, this study employed four series of modifications in which systematic substitution to the thienopyrimidine core was explored and ultimately side-chain elements optimized from the two original hits were merged into lead compounds. During the development of this series, the mode of action studies identified H. pylori's respiratory complex I subunit NuoD as the target for lead thienopyrimidines. As this enzyme complex is uniquely essential for ATP synthesis in H. pylori, a homology model of the H. pylori NuoB-NuoD binding interface was generated to help rationalize the SAR and guide further development of the series. From these studies, lead compounds emerged with increased potency against H. pylori, improved safety indices, and a good overall pharmacokinetic profile with the exception of high protein binding and poor solubility. Although lead compounds in the series demonstrated efficacy in an ex vivo infection model, the compounds had no efficacy in a mouse model of H. pylori infection. Additional optimization of pharmacological properties of the series to increase solubility and free-drug levels at the sequestered sites of H. pylori infection would potentially result in a gain of in vivo efficacy. The thienopyrimidine series developed in this study demonstrates that NuoB-NuoD of the respiratory complex I can be targeted for development of novel narrow spectrum agents against H. pylori and that thienopyrimines can serve as the basis for future advancement of these studies.
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Affiliation(s)
- Alex K. Mugengana
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, MS#1000, Memphis, Tennessee 38105, United States
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Nicole A. Vita
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, MS#1000, Memphis, Tennessee 38105, United States
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | | | - Kevin Moran
- Arietis Pharma, Boston, Massachusetts 02118, United States
| | | | - Lalit K. Sharma
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, MS#1000, Memphis, Tennessee 38105, United States
| | - Elizabeth C. Griffith
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, MS#1000, Memphis, Tennessee 38105, United States
| | - Jiuyu Liu
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, MS#1000, Memphis, Tennessee 38105, United States
| | - Lei Yang
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, MS#1000, Memphis, Tennessee 38105, United States
| | | | - Kirk E. Hevener
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | | | - Richard E. Lee
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, MS#1000, Memphis, Tennessee 38105, United States
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17
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Zuchan K, Baymann F, Baffert C, Brugna M, Nitschke W. The dyad of the Y-junction- and a flavin module unites diverse redox enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2021; 1862:148401. [PMID: 33684340 DOI: 10.1016/j.bbabio.2021.148401] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 02/09/2021] [Accepted: 02/16/2021] [Indexed: 11/26/2022]
Abstract
The concomitant presence of two distinctive polypeptide modules, which we have chosen to denominate as the "Y-junction" and the "flavin" module, is observed in 3D structures of enzymes as functionally diverse as complex I, NAD(P)-dependent [NiFe]-hydrogenases and NAD(P)-dependent formate dehydrogenases. Amino acid sequence conservation furthermore suggests that both modules are also part of NAD(P)-dependent [FeFe]-hydrogenases for which no 3D structure model is available yet. The flavin module harbours the site of interaction with the substrate NAD(P) which exchanges two electrons with a strictly conserved flavin moiety. The Y-junction module typically contains four iron-sulphur centres arranged to form a Y-shaped electron transfer conduit and mediates electron transfer between the flavin module and the catalytic units of the respective enzymes. The Y-junction module represents an electron transfer hub with three potential electron entry/exit sites. The pattern of specific redox centres present both in the Y-junction and the flavin module is correlated to present knowledge of these enzymes' functional properties. We have searched publicly accessible genomes for gene clusters containing both the Y-junction and the flavin module to assemble a comprehensive picture of the diversity of enzymes harbouring this dyad of modules and to reconstruct their phylogenetic relationships. These analyses indicate the presence of the dyad already in the last universal common ancestor and the emergence of complex I's EFG-module out of a subgroup of NAD(P)- dependent formate dehydrogenases.
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Affiliation(s)
- Kilian Zuchan
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France
| | - Frauke Baymann
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France
| | - Carole Baffert
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France
| | - Myriam Brugna
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France.
| | - Wolfgang Nitschke
- Aix Marseille Univ, CNRS, BIP, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 09, France
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18
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Pamplona R, Jové M, Mota-Martorell N, Barja G. Is the NDUFV2 subunit of the hydrophilic complex I domain a key determinant of animal longevity? FEBS J 2021; 288:6652-6673. [PMID: 33455045 DOI: 10.1111/febs.15714] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 12/02/2020] [Accepted: 01/14/2021] [Indexed: 12/18/2022]
Abstract
Complex I, a component of the electron transport chain, plays a central functional role in cell bioenergetics and the biology of free radicals. The structural and functional N module of complex I is one of the main sites of the generation of free radicals. The NDUFV2 subunit/N1a cluster is a component of this module. Furthermore, the rate of free radical production is linked to animal longevity. In this review, we explore the hypothesis that NDUFV2 is the only conserved core subunit designed with a regulatory function to ensure correct electron transfer and free radical production, that low gene expression and protein abundance of the NDUFV2 subunit is an evolutionary adaptation needed to achieve a longevity phenotype, and that these features are determinants of the lower free radical generation at the mitochondrial level and a slower rate of aging of long-lived animals.
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Affiliation(s)
- Reinald Pamplona
- Department of Experimental Medicine, University of Lleida-Lleida Biomedical Research Institute (UdL-IRBLleida), Lleida, Spain
| | - Mariona Jové
- Department of Experimental Medicine, University of Lleida-Lleida Biomedical Research Institute (UdL-IRBLleida), Lleida, Spain
| | - Natalia Mota-Martorell
- Department of Experimental Medicine, University of Lleida-Lleida Biomedical Research Institute (UdL-IRBLleida), Lleida, Spain
| | - Gustavo Barja
- Department of Genetics, Physiology and Microbiology, Complutense University of Madrid, Madrid, Spain
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19
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Miller NT, Vaughn MD, Burnap RL. Electron flow through NDH-1 complexes is the major driver of cyclic electron flow-dependent proton pumping in cyanobacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1862:148354. [PMID: 33338488 DOI: 10.1016/j.bbabio.2020.148354] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 12/03/2020] [Accepted: 12/08/2020] [Indexed: 01/12/2023]
Abstract
Cyclic electron flow (CEF) around photosystem I is vital to balancing the photosynthetic energy budget of cyanobacteria and other photosynthetic organisms. The coupling of CEF to proton pumping has long been hypothesized to occur, providing proton motive force (PMF) for the synthesis of ATP with no net cost to [NADPH]. This is thought to occur largely through the activity of NDH-1 complexes, of which cyanobacteria have four with different activities. While a much work has been done to understand the steady-state PMF in both the light and dark, and fluorescent probes have been developed to observe these fluxes in vivo, little has been done to understand the kinetics of these fluxes, particularly with regard to NDH-1 complexes. To monitor the kinetics of proton pumping in Synechocystis sp. PCC 6803, the pH sensitive dye Acridine Orange was used alongside a suite of inhibitors in order to observe light-dependent proton pumping. The assay was demonstrated to measure photosynthetically driven proton pumping and used to measure the rates of proton pumping unimpeded by dark ΔpH. Here, the cyanobacterial NDH-1 complexes are shown to pump a sizable portion of proton flux when CEF-driven and LEF-driven proton pumping rates are observed and compared in mutants lacking some or all NDH-1 complexes. It is also demonstrated that PSII and LEF are responsible for the bulk of light induced proton pumping, though CEF and NDH-1 are capable of generating ~40% of the proton pumping rate when LEF is inactivated.
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Affiliation(s)
- Neil T Miller
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078, USA
| | - Michael D Vaughn
- SpectroLogix LLC, 9050 Executive Park Drive, Knoxville, TN 37923, USA
| | - Robert L Burnap
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK 74078, USA.
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20
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Liu XD, Li YG, Wang GY, Bi YG, Zhao Y, Yan ML, Liu X, Wei M, Wan LL, Zhang QY. Metformin protects high glucose‑cultured cardiomyocytes from oxidative stress by promoting NDUFA13 expression and mitochondrial biogenesis via the AMPK signaling pathway. Mol Med Rep 2020; 22:5262-5270. [PMID: 33174032 PMCID: PMC7646981 DOI: 10.3892/mmr.2020.11599] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 06/01/2020] [Indexed: 01/16/2023] Open
Abstract
Tissue damage in diabetes is at least partly due to elevated reactive oxygen species production by the mitochondrial respiratory chain during hyperglycemia. Sustained hyperglycemia results in mitochondrial dysfunction and the abnormal expression of mitochondrial genes, such as NADH: Ubiquinone oxidoreductase subunit A13 (NDUFA13). Metformin, an AMP-activated protein kinase (AMPK) activator, protects cardiomyocytes from oxidative stress by improving mitochondrial function; however, the exact underlying mechanisms are not completely understood. The aim of the present study was to investigated the molecular changes and related regulatory mechanisms in the response of H9C2 cardiomyocytes to metformin under high glucose conditions. H9C2 cells were subjected to CCK-8 assay to assess cell viability. Reactive oxygen species generation was measured with DCFH-DA assay. Western blotting was used to analyze the expression levels of NDUFA13, AMPK, p-AMPK and GAPDH. Reverse transcription-quantitative PCR was used to evaluate the expression levels of mitochondrial genes and transcription factors. It was observed that metformin protected H9C2 cardiomyocytes by suppressing high glucose (HG)-induced elevated oxidative stress. In addition, metformin stimulated mitochondrial biogenesis, as indicated by increased expression levels of mitochondrial genes (NDUFA1, NDUFA2, NDUFA13 and manganese superoxide dismutase) and mitochondrial biogenesis-related transcription factors [peroxisome proliferator-activated receptor-gamma coactivator-1α, nuclear respiratory factor (NRF)-1, and NRF-2] in the metformin + HG group compared with the HG group. Moreover, metformin promoted mitochondrial NDUFA13 protein expression via the AMPK signaling pathway, which was abolished by pretreatment with the AMPK inhibitor, Compound C. The results suggested that metformin protected cardiomyocytes against HG-induced oxidative stress via a mechanism involving AMPK, NDUFA13 and mitochondrial biogenesis.
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Affiliation(s)
- Xiang-Dong Liu
- Department of Cardiology, Tongji Hospital, School of Medicine, Tongji University, Shanghai 200065, P.R. China
| | - Yong-Guang Li
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Guang-Yu Wang
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Ya-Guang Bi
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Yu Zhao
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Mei-Ling Yan
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Xuebo Liu
- Department of Cardiology, Tongji Hospital, School of Medicine, Tongji University, Shanghai 200065, P.R. China
| | - Meng Wei
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Li-Li Wan
- Division of Pharmacy, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, P.R. China
| | - Qing-Yong Zhang
- Department of Cardiology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, P.R. China
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21
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Kadnikov VV, Mardanov AV, Beletsky AV, Karnachuk OV, Ravin NV. Microbial Life in the Deep Subsurface Aquifer Illuminated by Metagenomics. Front Microbiol 2020; 11:572252. [PMID: 33013807 PMCID: PMC7509429 DOI: 10.3389/fmicb.2020.572252] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 08/13/2020] [Indexed: 01/08/2023] Open
Abstract
To get insights into microbial diversity and biogeochemical processes in the terrestrial deep subsurface aquifer, we sequenced the metagenome of artesian water collected at a 2.8 km deep oil exploration borehole 5P in Western Siberia, Russia. We obtained 71 metagenome-assembled genomes (MAGs), altogether comprising 93% of the metagenome. Methanogenic archaea accounted for about 20% of the community and mostly belonged to hydrogenotrophic Methanobacteriaceae; acetoclastic and methylotrophic lineages were less abundant. ANME archaea were not found. The most numerous bacteria were the Firmicutes, Ignavibacteriae, Deltaproteobacteria, Chloroflexi, and Armatimonadetes. Most of the community was composed of anaerobic heterotrophs. Only six MAGs belonged to sulfate reducers. These MAGs accounted for 5% of the metagenome and were assigned to the Firmicutes, Deltaproteobacteria, Candidatus Kapabacteria, and Nitrospirae. Organotrophic bacteria carrying cytochrome c oxidase genes and presumably capable of aerobic respiration mostly belonged to the Chloroflexi, Ignavibacteriae, and Armatimonadetes. They accounted for 13% of the community. The first complete closed genomes were obtained for members of the Ignavibacteriae SJA-28 lineage and the candidate phylum Kapabacteria. Metabolic reconstruction of the SJA-28 bacterium, designated Candidatus Tepidiaquacella proteinivora, predicted that it is an anaerobe growing on proteinaceous substrates by fermentation or anaerobic respiration. The Ca. Kapabacteria genome contained both the sulfate reduction pathway and cytochrome c oxidase. Presumably, the availability of buried organic matter of Mesozoic marine sediments, long-term recharge of the aquifer with meteoric waters and its spatial heterogeneity provided the conditions for the development of microbial communities, taxonomically and functionally more diverse than those found in oligotrophic underground ecosystems.
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Affiliation(s)
- Vitaly V Kadnikov
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Andrey V Mardanov
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Alexey V Beletsky
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Olga V Karnachuk
- Laboratory of Biochemistry and Molecular Biology, Tomsk State University, Tomsk, Russia
| | - Nikolai V Ravin
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
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22
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Melin F, Hellwig P. Redox Properties of the Membrane Proteins from the Respiratory Chain. Chem Rev 2020; 120:10244-10297. [DOI: 10.1021/acs.chemrev.0c00249] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Frederic Melin
- Chimie de la Matière Complexe UMR 7140, Laboratoire de Bioelectrochimie et Spectroscopie, CNRS-Université de Strasbourg, 1 rue Blaise Pascal, 67070 Strasbourg, France
| | - Petra Hellwig
- Chimie de la Matière Complexe UMR 7140, Laboratoire de Bioelectrochimie et Spectroscopie, CNRS-Université de Strasbourg, 1 rue Blaise Pascal, 67070 Strasbourg, France
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23
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Gutiérrez-Fernández J, Kaszuba K, Minhas GS, Baradaran R, Tambalo M, Gallagher DT, Sazanov LA. Key role of quinone in the mechanism of respiratory complex I. Nat Commun 2020; 11:4135. [PMID: 32811817 PMCID: PMC7434922 DOI: 10.1038/s41467-020-17957-0] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 07/28/2020] [Indexed: 01/12/2023] Open
Abstract
Complex I is the first and the largest enzyme of respiratory chains in bacteria and mitochondria. The mechanism which couples spatially separated transfer of electrons to proton translocation in complex I is not known. Here we report five crystal structures of T. thermophilus enzyme in complex with NADH or quinone-like compounds. We also determined cryo-EM structures of major and minor native states of the complex, differing in the position of the peripheral arm. Crystal structures show that binding of quinone-like compounds (but not of NADH) leads to a related global conformational change, accompanied by local re-arrangements propagating from the quinone site to the nearest proton channel. Normal mode and molecular dynamics analyses indicate that these are likely to represent the first steps in the proton translocation mechanism. Our results suggest that quinone binding and chemistry play a key role in the coupling mechanism of complex I. Complex I (NADH:ubiquinone oxidoreductase) is the first enzyme of the respiratory chain in bacteria and mitochondria. Here, the authors present cryo-EM and crystal structures of T. thermophilus complex I in different conformational states and further analyse them by Normal Mode Analysis and molecular dynamics simulations and conclude that quinone redox reactions are important for the coupling mechanism of complex I.
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Affiliation(s)
| | - Karol Kaszuba
- Institute of Science and Technology Austria, Am Campus 1, A-3400, Klosterneuburg, Austria
| | - Gurdeep S Minhas
- Medical Research Council Mitochondrial Biology Unit, Keith Peters Building, Hills rd, Cambridge, CB2 0XY, UK.,Sosei Heptares, Steinmetz Building, Granta Park, Cambridge, CB21 6DG, UK
| | - Rozbeh Baradaran
- Medical Research Council Mitochondrial Biology Unit, Keith Peters Building, Hills rd, Cambridge, CB2 0XY, UK.,Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden
| | - Margherita Tambalo
- Institute of Science and Technology Austria, Am Campus 1, A-3400, Klosterneuburg, Austria
| | - David T Gallagher
- Medical Research Council Mitochondrial Biology Unit, Keith Peters Building, Hills rd, Cambridge, CB2 0XY, UK
| | - Leonid A Sazanov
- Institute of Science and Technology Austria, Am Campus 1, A-3400, Klosterneuburg, Austria.
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24
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Losey NA, Poudel S, Boyd ES, McInerney MJ. The Beta Subunit of Non-bifurcating NADH-Dependent [FeFe]-Hydrogenases Differs From Those of Multimeric Electron-Bifurcating [FeFe]-Hydrogenases. Front Microbiol 2020; 11:1109. [PMID: 32625172 PMCID: PMC7311640 DOI: 10.3389/fmicb.2020.01109] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 05/04/2020] [Indexed: 12/29/2022] Open
Abstract
A non-bifurcating NADH-dependent, dimeric [FeFe]-hydrogenase (HydAB) from Syntrophus aciditrophicus was heterologously produced in Escherichia coli, purified and characterized. Purified recombinant HydAB catalyzed NAD+ reduction coupled to hydrogen oxidation and produced hydrogen from NADH without the involvement of ferredoxin. Hydrogen partial pressures (2.2-40.2 Pa) produced by the purified recombinant HydAB at NADH to NAD+ ratios of 1-5 were similar to the hydrogen partial pressures generated by pure and cocultures of S. aciditrophicus (5.9-36.6 Pa). Thus, the hydrogen partial pressures observed in metabolizing cultures and cocultures of S. aciditrophicus can be generated by HydAB if S. aciditrophicus maintains NADH to NAD+ ratios greater than one. The flavin-containing beta subunits from S. aciditrophicus HydAB and the non-bifurcating NADH-dependent S. wolfei Hyd1ABC share a number of conserved residues with the flavin-containing beta subunits from non-bifurcating NADH-dependent enzymes such as NADH:quinone oxidoreductases and formate dehydrogenases. A number of differences were observed between sequences of these non-bifurcating NADH-dependent enzymes and [FeFe]-hydrogenases and formate dehydrogenases known to catalyze electron bifurcation including differences in the number of [Fe-S] centers and in conserved residues near predicted cofactor binding sites. These differences can be used to distinguish members of these two groups of enzymes and may be relevant to the differences in ferredoxin-dependence and ability to mediate electron-bifurcation. These results show that two phylogenetically distinct syntrophic fatty acid-oxidizing bacteria, Syntrophomonas wolfei a member of the phylum Firmicutes, and S. aciditrophicus, a member of the class Deltaproteobacteria, possess functionally similar [FeFe]-hydrogenases that produce hydrogen from NADH during syntrophic fatty acid oxidation without the involvement of reduced ferredoxin. The reliance on a non-bifurcating NADH-dependent [FeFe]-hydrogenases may explain the obligate requirement that many syntrophic metabolizers have for a hydrogen-using partner microorganism when grown on fatty, aromatic and alicyclic acids.
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Affiliation(s)
- Nathaniel A Losey
- Department of Plant Biology and Microbiology, The University of Oklahoma, Norman, OK, United States
| | - Saroj Poudel
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - Eric S Boyd
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - Michael J McInerney
- Department of Plant Biology and Microbiology, The University of Oklahoma, Norman, OK, United States
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25
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Khaniya U, Gupta C, Cai X, Mao J, Kaur D, Zhang Y, Singharoy A, Gunner MR. Hydrogen bond network analysis reveals the pathway for the proton transfer in the E-channel of T. thermophilus Complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148240. [PMID: 32531220 DOI: 10.1016/j.bbabio.2020.148240] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 05/19/2020] [Accepted: 06/03/2020] [Indexed: 10/24/2022]
Abstract
Complex I, NADH-ubiquinone oxidoreductase, is the first enzyme in the mitochondrial and bacterial aerobic respiratory chain. It pumps four protons through four transiently open pathways from the high pH, negative, N-side of the membrane to the positive, P-side driven by the exergonic transfer of electrons from NADH to a quinone. Three protons transfer through subunits descended from antiporters, while the fourth, E-channel is unique. The path through the E-channel is determined by a network analysis of hydrogen bonded pathways obtained by Monte Carlo sampling of protonation states, polar hydrogen orientation and water occupancy. Input coordinates are derived from molecular dynamics trajectories comparing oxidized, reduced (dihydro) and no menaquinone-8 (MQ). A complex proton transfer path from the N- to the P-side is found consisting of six clusters of highly connected hydrogen-bonded residues. The network connectivity depends on the presence of quinone and its redox state, supporting a role for this cofactor in coupling electron and proton transfers. The N-side is more organized with MQ-bound complex I facilitating proton entry, while the P-side is more connected in the apo-protein, facilitating proton exit. Subunit Nqo8 forms the core of the E channel; Nqo4 provides the N-side entry, Nqo7 and then Nqo10 join the pathway in the middle, while Nqo11 contributes to the P-side exit.
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Affiliation(s)
- Umesh Khaniya
- Department of Physics, City College of New York, New York 10031, USA; Department of Physics, The Graduate Center, City University of New York, New York 10016, USA
| | - Chitrak Gupta
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA; Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Xiuhong Cai
- Department of Physics, City College of New York, New York 10031, USA; Department of Physics, The Graduate Center, City University of New York, New York 10016, USA
| | - Junjun Mao
- Department of Physics, City College of New York, New York 10031, USA
| | - Divya Kaur
- Department of Physics, City College of New York, New York 10031, USA; Department of Chemistry, The Graduate Center, City University of New York, New York 10016, USA
| | - Yingying Zhang
- Department of Physics, City College of New York, New York 10031, USA; Department of Physics, The Graduate Center, City University of New York, New York 10016, USA
| | - Abhishek Singharoy
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA; Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - M R Gunner
- Department of Physics, City College of New York, New York 10031, USA; Department of Physics, The Graduate Center, City University of New York, New York 10016, USA; Department of Chemistry, The Graduate Center, City University of New York, New York 10016, USA.
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26
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Gupta C, Khaniya U, Chan CK, Dehez F, Shekhar M, Gunner MR, Sazanov L, Chipot C, Singharoy A. Charge Transfer and Chemo-Mechanical Coupling in Respiratory Complex I. J Am Chem Soc 2020; 142:9220-9230. [PMID: 32347721 DOI: 10.1021/jacs.9b13450] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The mitochondrial respiratory chain, formed by five protein complexes, utilizes energy from catabolic processes to synthesize ATP. Complex I, the first and the largest protein complex of the chain, harvests electrons from NADH to reduce quinone, while pumping protons across the mitochondrial membrane. Detailed knowledge of the working principle of such coupled charge-transfer processes remains, however, fragmentary due to bottlenecks in understanding redox-driven conformational transitions and their interplay with the hydrated proton pathways. Complex I from Thermus thermophilus encases 16 subunits with nine iron-sulfur clusters, reduced by electrons from NADH. Here, employing the latest crystal structure of T. thermophilus complex I, we have used microsecond-scale molecular dynamics simulations to study the chemo-mechanical coupling between redox changes of the iron-sulfur clusters and conformational transitions across complex I. First, we identify the redox switches within complex I, which allosterically couple the dynamics of the quinone binding pocket to the site of NADH reduction. Second, our free-energy calculations reveal that the affinity of the quinone, specifically menaquinone, for the binding-site is higher than that of its reduced, menaquinol form-a design essential for menaquinol release. Remarkably, the barriers to diffusive menaquinone dynamics are lesser than that of the more ubiquitous ubiquinone, and the naphthoquinone headgroup of the former furnishes stronger binding interactions with the pocket, favoring menaquinone for charge transport in T. thermophilus. Our computations are consistent with experimentally validated mutations and hierarchize the key residues into three functional classes, identifying new mutation targets. Third, long-range hydrogen-bond networks connecting the quinone-binding site to the transmembrane subunits are found to be responsible for proton pumping. Put together, the simulations reveal the molecular design principles linking redox reactions to quinone turnover to proton translocation in complex I.
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Affiliation(s)
- Chitrak Gupta
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85281, United States.,Biodesign Institute, Arizona State University, Tempe, Arizona 85281, United States
| | - Umesh Khaniya
- Department of Physics, City College of New York, New York, New York 10031, United States.,Department of Physics, City University of New York, New York, New York 10017, United States
| | - Chun Kit Chan
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | | | - Mrinal Shekhar
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - M R Gunner
- Department of Physics, City College of New York, New York, New York 10031, United States.,Department of Physics, City University of New York, New York, New York 10017, United States
| | - Leonid Sazanov
- Institute of Science and Technology, 3400 Klosterneuburg, Austria
| | - Christophe Chipot
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.,University of Lorraine, Nancy 54000, France
| | - Abhishek Singharoy
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85281, United States.,Biodesign Institute, Arizona State University, Tempe, Arizona 85281, United States
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27
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Dwivedi D, Megha K, Mishra R, Mandal PK. Glutathione in Brain: Overview of Its Conformations, Functions, Biochemical Characteristics, Quantitation and Potential Therapeutic Role in Brain Disorders. Neurochem Res 2020; 45:1461-1480. [PMID: 32297027 DOI: 10.1007/s11064-020-03030-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 04/04/2020] [Accepted: 04/07/2020] [Indexed: 12/28/2022]
Abstract
Glutathione (GSH) is an important antioxidant found abundantly and synthesized intracellularly in the cytosol in a tightly regulated fashion. It has diverse physiological functions, including protection against reactive oxygen species and nitrogen species, antioxidant defense as well as maintenance of cellular thiol status. The human brain due to the high oxygen consumption is extremely susceptible to the generation of reactive oxygen species. GSH plays a paramount role in brain antioxidant defense, maintaining redox homeostasis. The depletion of brain GSH has also been observed from both autopsies as well as in vivo MRS studies with aging and varied neurological disorders (Alzheimer's disease, Parkinson's disease, etc.). Therefore, GSH enrichment using supplementation is a promising avenue in the therapeutic development for these neurological disorders. This review will enrich the information on the importance of GSH synthesis, metabolism, functions, compartmentation and inter-organ transport, structural conformations and its quantitation via different techniques. The transportation of GSH in the brain via different interventional routes and its potential role in the development of therapeutic strategies for various brain disorders is also addressed. Very recent study found significant improvement of behavioral deficits including cognitive decline, depressive-like behaviors, in APP (NL-G-F/NL-G-FG-) mice due to oral GSH administration. This animal model study put an emergent need to complete GSH supplementation trial in MCI and AD patients for cognitive improvement as proposed earlier.
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Affiliation(s)
- Divya Dwivedi
- Neuroimaging and Neurospectroscopy (NINS) Laboratory, National Brain Research Centre, Manesar, Gurgaon, Haryana, India
| | - Kanu Megha
- Neuroimaging and Neurospectroscopy (NINS) Laboratory, National Brain Research Centre, Manesar, Gurgaon, Haryana, India
| | - Ritwick Mishra
- Neuroimaging and Neurospectroscopy (NINS) Laboratory, National Brain Research Centre, Manesar, Gurgaon, Haryana, India
| | - Pravat K Mandal
- Neuroimaging and Neurospectroscopy (NINS) Laboratory, National Brain Research Centre, Manesar, Gurgaon, Haryana, India. .,Florey Institute of Neuroscience and Mental Health, Melbourne School of Medicine Campus, Parkville, Melbourne, Australia.
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28
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Rusetskaya NY, Fedotov IV, Koftina VA, Borodulin VB. Selenium Compounds in Redox Regulation of Inflammation and Apoptosis. BIOCHEMISTRY (MOSCOW), SUPPLEMENT SERIES B: BIOMEDICAL CHEMISTRY 2019. [DOI: 10.1134/s1990750819040085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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29
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Santos Seica AF, Schimpf J, Friedrich T, Hellwig P. Visualizing the movement of the amphipathic helix in the respiratory complex I using a nitrile infrared probe and SEIRAS. FEBS Lett 2019; 594:491-496. [PMID: 31556114 DOI: 10.1002/1873-3468.13620] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 09/20/2019] [Accepted: 09/23/2019] [Indexed: 01/22/2023]
Abstract
Conformational movements play an important role in enzyme catalysis. Respiratory complex I, an L-shaped enzyme, connects electron transfer from NADH to ubiquinone in its peripheral arm with proton translocation through its membrane arm by a coupling mechanism still under debate. The amphipathic helix across the membrane arm represents a unique structural feature. Here, we demonstrate a new way to study conformational changes by introducing a small and highly flexible nitrile infrared (IR) label to this helix to visualize movement with surface-enhanced IR absorption spectroscopy. We find that labeled residues K551CL and Y590CL move to a more hydrophobic environment upon NADH reduction of the enzyme, likely as a response to the reorganization of the antiporter-like subunits in the membrane arm.
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Affiliation(s)
- Ana Filipa Santos Seica
- Laboratoire de Bioélectrochimie et Spectroscopie, UMR 7140, CMC, Université de Strasbourg CNRS, France
| | - Johannes Schimpf
- Institut für Biochemie, Albert-Ludwigs-Universität Freiburg, Germany
| | | | - Petra Hellwig
- Laboratoire de Bioélectrochimie et Spectroscopie, UMR 7140, CMC, Université de Strasbourg CNRS, France.,University of Strasbourg Institute for Advanced Studies (USIAS), France
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30
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Rusetskaya NY, Fedotov IV, Koftina VA, Borodulin VB. [Selenium compounds in redox regulation of inflammation and apoptosis]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2019; 65:165-179. [PMID: 31258141 DOI: 10.18097/pbmc20196503165] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Monocytes and macrophages play a key role in the development of inflammation: under the action of lipopolysaccharides (LPS), absorbed from the intestine, monocytes and macrophages form reactive oxygen species (ROS) and cytokines, this leads to the development of oxidative stress, inflammation and/or apoptosis in all types of tissues. In the cells LPS induce an "internal" TLR4-mediated MAP-kinase inflammatory signaling pathway and cytokines through the superfamily of tumor necrosis factor receptor (TNFR) and the "death domain" (DD) initiate an "external" caspase apoptosis cascade or necrosis activation that causes necroptosis. Many of the proteins involved in intracellular signaling cascades (MYD88, ASK1, IKKa/b, NF-kB, AP-1) are redox-sensitive and their activity is regulated by antioxidants thioredoxin, glutaredoxin, nitroredoxin, and glutathione. Oxidation of these signaling proteins induced by ROS enhances the development of inflammation and apoptosis, and their reduction with antioxidants, on the contrary, stabilizes the signaling cascades speed, preventing the vicious circle of oxidative stress, inflammation and apoptosis that follows it. Antioxidant (AO) enzymes thioredoxin reductase (TRXR), glutaredoxin reductase (GLRXR), glutathione reductase (GR) are required for reduction of non-enzymatic antioxidants (thioredoxin, glutaredoxin, nitroredoxin, glutathione), and AO enzymes (SOD, catalase, GPX) are required for ROS deactivation. The key AO enzymes (TRXR and GPX) are selenium-dependent; therefore selenium deficiency leads to a decrease in the body's antioxidant defense, the development of oxidative stress, inflammation, and/or apoptosis in various cell types. Nrf2-Keap1 signaling pathway activated by selenium deficiency and/or oxidative stress is necessary to restore redox homeostasis in the cell. In addition, expression of some genes is changed with selenium deficiency. Consequently, growth and proliferation of cells, their movement, development, death, and survival, as well as the interaction between cells, the redox regulation of intracellular signaling cascades of inflammation and apoptosis, depend on the selenium status of the body. Prophylactic administration of selenium-containing preparations (natural and synthetic (organic and inorganic)) is able to normalize the activity of AO enzymes and the general status of the body. Organic selenium compounds have a high bioavailability and, depending on their concentration, can act both as selenium donors to prevent selenium deficiency and as antitumor drugs due to their toxicity and participation in the regulation of signaling pathways of apoptosis. Known selenorganic compounds diphenyldiselenide and ethaselen share similarity with the Russian organo selenium compound, diacetophenonylselenide (DAPS-25), which serves as a source of bioavailable selenium, exhibits a wide range of biological activity, including antioxidant activity, that governs cell redox balance, inflammation and apoptosis regulation.
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Affiliation(s)
- N Y Rusetskaya
- Razumovsky Saratov State Medical University, Saratov, Russia
| | - I V Fedotov
- Razumovsky Saratov State Medical University, Saratov, Russia
| | - V A Koftina
- Razumovsky Saratov State Medical University, Saratov, Russia
| | - V B Borodulin
- Razumovsky Saratov State Medical University, Saratov, Russia
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31
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Tran KN, Niu S, Ichiye T. Reduction potential calculations of the Fe–S clusters in
Thermus thermophilus
respiratory complex I. J Comput Chem 2019; 40:1248-1256. [DOI: 10.1002/jcc.25785] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 12/12/2018] [Accepted: 01/06/2019] [Indexed: 01/12/2023]
Affiliation(s)
- Kelly N. Tran
- Department of ChemistryGeorgetown University Washington District of Columbia, 20057
| | - Shuqiang Niu
- Department of ChemistryGeorgetown University Washington District of Columbia, 20057
| | - Toshiko Ichiye
- Department of ChemistryGeorgetown University Washington District of Columbia, 20057
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32
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Schuller JM, Birrell JA, Tanaka H, Konuma T, Wulfhorst H, Cox N, Schuller SK, Thiemann J, Lubitz W, Sétif P, Ikegami T, Engel BD, Kurisu G, Nowaczyk MM. Structural adaptations of photosynthetic complex I enable ferredoxin-dependent electron transfer. Science 2018; 363:257-260. [PMID: 30573545 DOI: 10.1126/science.aau3613] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 12/06/2018] [Indexed: 12/22/2022]
Abstract
Photosynthetic complex I enables cyclic electron flow around photosystem I, a regulatory mechanism for photosynthetic energy conversion. We report a 3.3-angstrom-resolution cryo-electron microscopy structure of photosynthetic complex I from the cyanobacterium Thermosynechococcus elongatus. The model reveals structural adaptations that facilitate binding and electron transfer from the photosynthetic electron carrier ferredoxin. By mimicking cyclic electron flow with isolated components in vitro, we demonstrate that ferredoxin directly mediates electron transfer between photosystem I and complex I, instead of using intermediates such as NADPH (the reduced form of nicotinamide adenine dinucleotide phosphate). A large rate constant for association of ferredoxin to complex I indicates efficient recognition, with the protein subunit NdhS being the key component in this process.
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Affiliation(s)
- Jan M Schuller
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
| | - James A Birrell
- Max Planck Institute for Chemical Energy Conversion, 45470 Mülheim an der Ruhr, Germany
| | - Hideaki Tanaka
- Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan.,Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
| | - Tsuyoshi Konuma
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Hannes Wulfhorst
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany.,Daiichi Sankyo Deutschland GmbH, Zielstattstr. 48, 81379 München, Germany
| | - Nicholas Cox
- Max Planck Institute for Chemical Energy Conversion, 45470 Mülheim an der Ruhr, Germany.,Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Sandra K Schuller
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Jacqueline Thiemann
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion, 45470 Mülheim an der Ruhr, Germany
| | - Pierre Sétif
- Institut de Biologie Intégrative de la Cellule (I2BC), IBITECS, CEA, CNRS, Université Paris-Saclay, F-91198 Gif-sur-Yvette, France
| | - Takahisa Ikegami
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Benjamin D Engel
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Genji Kurisu
- Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan. .,Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
| | - Marc M Nowaczyk
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany.
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33
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Salazar C, Ruiz-Hincapie P, Ruiz LM. The Interplay among PINK1/PARKIN/Dj-1 Network during Mitochondrial Quality Control in Cancer Biology: Protein Interaction Analysis. Cells 2018; 7:cells7100154. [PMID: 30274236 PMCID: PMC6210981 DOI: 10.3390/cells7100154] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 09/14/2018] [Accepted: 09/25/2018] [Indexed: 12/18/2022] Open
Abstract
PARKIN (E3 ubiquitin ligase PARK2), PINK1 (PTEN induced kinase 1) and DJ-1 (PARK7) are proteins involved in autosomal recessive parkinsonism, and carcinogenic processes. In damaged mitochondria, PINK1’s importing into the inner mitochondrial membrane is prevented, PARKIN presents a partial mitochondrial localization at the outer mitochondrial membrane and DJ-1 relocates to mitochondria when oxidative stress increases. Depletion of these proteins result in abnormal mitochondrial morphology. PINK1, PARKIN, and DJ-1 participate in mitochondrial remodeling and actively regulate mitochondrial quality control. In this review, we highlight that PARKIN, PINK1, and DJ-1 should be regarded as having an important role in Cancer Biology. The STRING database and Gene Ontology (GO) enrichment analysis were performed to consolidate knowledge of well-known protein interactions for PINK1, PARKIN, and DJ-1 and envisage new ones. The enrichment analysis of KEGG pathways showed that the PINK1/PARKIN/DJ-1 network resulted in Parkinson disease as the main feature, while the protein DJ-1 showed enrichment in prostate cancer and p53 signaling pathway. Some predicted transcription factors regulating PINK1, PARK2 (PARKIN) and PARK7 (DJ-1) gene expression are related to cell cycle control. We can therefore suggest that the interplay among PINK1/PARKIN/DJ-1 network during mitochondrial quality control in cancer biology may occur at the transcriptional level. Further analysis, like a systems biology approach, will be helpful in the understanding of PINK1/PARKIN/DJ-1 network.
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Affiliation(s)
- Celia Salazar
- Instituto de Investigaciones Biomédicas, Universidad Autónoma de Chile, Santiago 8910060, Chile.
| | - Paula Ruiz-Hincapie
- School of Engineering and Technology, University of Hertfordshire, Hatfield AL 10 9AB, UK.
| | - Lina María Ruiz
- Instituto de Investigaciones Biomédicas, Universidad Autónoma de Chile, Santiago 8910060, Chile.
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34
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Fiedorczuk K, Sazanov LA. Mammalian Mitochondrial Complex I Structure and Disease-Causing Mutations. Trends Cell Biol 2018; 28:835-867. [PMID: 30055843 DOI: 10.1016/j.tcb.2018.06.006] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 06/14/2018] [Accepted: 06/22/2018] [Indexed: 12/31/2022]
Abstract
Complex I has an essential role in ATP production by coupling electron transfer from NADH to quinone with translocation of protons across the inner mitochondrial membrane. Isolated complex I deficiency is a frequent cause of mitochondrial inherited diseases. Complex I has also been implicated in cancer, ageing, and neurodegenerative conditions. Until recently, the understanding of complex I deficiency on the molecular level was limited due to the lack of high-resolution structures of the enzyme. However, due to developments in single particle cryo-electron microscopy (cryo-EM), recent studies have reported nearly atomic resolution maps and models of mitochondrial complex I. These structures significantly add to our understanding of complex I mechanism and assembly. The disease-causing mutations are discussed here in their structural context.
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Affiliation(s)
- Karol Fiedorczuk
- Institute of Science and Technology Austria, Am Campus 1, Klosterneuburg 3400, Austria; Present address: The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Leonid A Sazanov
- Institute of Science and Technology Austria, Am Campus 1, Klosterneuburg 3400, Austria.
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35
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Télot L, Rousseau E, Lesuisse E, Garcia C, Morlet B, Léger T, Camadro JM, Serre V. Quantitative proteomics in Friedreich's ataxia B-lymphocytes: A valuable approach to decipher the biochemical events responsible for pathogenesis. Biochim Biophys Acta Mol Basis Dis 2018; 1864:997-1009. [DOI: 10.1016/j.bbadis.2018.01.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 12/19/2017] [Accepted: 01/08/2018] [Indexed: 11/29/2022]
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36
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Electron leak from NDUFA13 within mitochondrial complex I attenuates ischemia-reperfusion injury via dimerized STAT3. Proc Natl Acad Sci U S A 2017; 114:11908-11913. [PMID: 29078279 PMCID: PMC5692532 DOI: 10.1073/pnas.1704723114] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Reactive oxygen species (ROS) generation due to electron leak from the mitochondria may be involved in physiological or pathological processes. NDUFA13 is an accessory subunit of mitochondria complex I with a unique molecular structure and is located close to FeS clusters with low electrochemical potentials. Here, we generated cardiac-specific conditional NDUFA13 heterozygous knockout mice. At the basal state, a moderate down-regulation of NDUFA13 created a leak within complex I, resulting in a mild increase in cytoplasm localized H2O2, but not superoxide. The resultant ROS served as a second messenger and was responsible for the STAT3 dimerization and, hence, the activation of antiapoptotic signaling, which eventually significantly suppressed the superoxide burst and decreased the infarct size during the ischemia-reperfusion process. The causative relationship between specific mitochondrial molecular structure and reactive oxygen species (ROS) generation has attracted much attention. NDUFA13 is a newly identified accessory subunit of mitochondria complex I with a unique molecular structure and a location that is very close to the subunits of complex I of low electrochemical potentials. It has been reported that down-regulated NDUFA13 rendered tumor cells more resistant to apoptosis. Thus, this molecule might provide an ideal opportunity for us to investigate the profile of ROS generation and its role in cell protection against apoptosis. In the present study, we generated cardiac-specific tamoxifen-inducible NDUFA13 knockout mice and demonstrated that cardiac-specific heterozygous knockout (cHet) mice exhibited normal cardiac morphology and function in the basal state but were more resistant to apoptosis when exposed to ischemia-reperfusion (I/R) injury. cHet mice showed a preserved capacity of oxygen consumption rate by complex I and II, which can match the oxygen consumption driven by electron donors of N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD)+ascorbate. Interestingly, at basal state, cHet mice exhibited a higher H2O2 level in the cytosol, but not in the mitochondria. Importantly, increased H2O2 served as a second messenger and led to the STAT3 dimerization and, hence, activation of antiapoptotic signaling, which eventually significantly suppressed the superoxide burst and decreased the infarct size during the I/R process in cHet mice.
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Structure and electrochemistry of proteins harboring iron-sulfur clusters of different nuclearities. Part I. [4Fe-4S] + [2Fe-2S] iron-sulfur proteins. J Struct Biol 2017; 200:1-19. [DOI: 10.1016/j.jsb.2017.05.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 05/25/2017] [Indexed: 01/08/2023]
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Stochastic resonance in a proton pumping Complex I of mitochondria membranes. Sci Rep 2017; 7:12405. [PMID: 28963519 PMCID: PMC5622088 DOI: 10.1038/s41598-017-12746-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 09/15/2017] [Indexed: 11/24/2022] Open
Abstract
We make use of the physical mechanism of proton pumping in the so-called Complex I within mitochondria membranes. Our model is based on sequential charge transfer assisted by conformational changes which facilitate the indirect electron-proton coupling. The equations of motion for the proton operators are derived and solved numerically in combination with the phenomenological Langevin equation describing the periodic conformational changes. We show that with an appropriate set of parameters, protons can be transferred against an applied voltage. In addition, we demonstrate that only the joint action of the periodic energy modulation and thermal noise leads to efficient uphill proton transfer, being a manifestation of stochastic resonance.
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Kato H, Thi Mai Pham T, Yamaza H, Masuda K, Hirofuji Y, Han X, Sato H, Taguchi T, Nonaka K. Mitochondria Regulate the Differentiation of Stem Cells from Human Exfoliated Deciduous Teeth. Cell Struct Funct 2017; 42:105-116. [PMID: 28701634 DOI: 10.1247/csf.17012] [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] [Indexed: 11/11/2022] Open
Abstract
Stem cells from human exfoliated deciduous teeth (SHED) are isolated from the dental pulp tissue of primary teeth and can differentiate into neuronal cells. Although SHED are a desirable type of stem cells for transplantation therapy and for the study of neurological diseases, a large part of the neuronal differentiation machinery of SHED remains unclear. Recent studies have suggested that mitochondrial activity is involved in the differentiation of stem cells. In the present work, we investigated the neuronal differentiation machinery of SHED by focusing on mitochondrial activity. During neuronal differentiation of SHED, we observed increased mitochondrial membrane potential, increased mitochondrial DNA, and elongated mitochondria. Furthermore, to examine the demand for mitochondrial activity in neuronal differentiation, we then differentiated SHED into neuronal cells in the presence of rotenone, an inhibitor of mitochondrial respiratory chain complex I, and carbonyl cyanide m-chlorophenyl hydrazone (CCCP), a mitochondrial uncoupler, and found that neuronal differentiation was inhibited by treatment with rotenone and CCCP. These results indicated that increased mitochondrial activity was crucial for the neuronal differentiation of SHED.Key words: mitochondria, differentiation, stem cells, dental pulp, exfoliated deciduous teeth.
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Affiliation(s)
- Hiroki Kato
- Section of Oral Medicine for Child, Division of Oral Health, Growth & Development, Faculty of Dental Science, Kyushu University
| | - Thanh Thi Mai Pham
- Section of Oral Medicine for Child, Division of Oral Health, Growth & Development, Faculty of Dental Science, Kyushu University
| | - Haruyoshi Yamaza
- Section of Oral Medicine for Child, Division of Oral Health, Growth & Development, Faculty of Dental Science, Kyushu University
| | - Keiji Masuda
- Section of Oral Medicine for Child, Division of Oral Health, Growth & Development, Faculty of Dental Science, Kyushu University
| | - Yuta Hirofuji
- Section of Oral Medicine for Child, Division of Oral Health, Growth & Development, Faculty of Dental Science, Kyushu University
| | - Xu Han
- Section of Oral Medicine for Child, Division of Oral Health, Growth & Development, Faculty of Dental Science, Kyushu University
| | - Hiroshi Sato
- Section of Oral Medicine for Child, Division of Oral Health, Growth & Development, Faculty of Dental Science, Kyushu University
| | - Tomoaki Taguchi
- Department of Pediatric Surgery, Reproductive and Developmental Medicine, Graduate School of Medical Sciences, Kyushu University
| | - Kazuaki Nonaka
- Section of Oral Medicine for Child, Division of Oral Health, Growth & Development, Faculty of Dental Science, Kyushu University
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Dörner K, Vranas M, Schimpf J, Straub IR, Hoeser J, Friedrich T. Significance of [2Fe-2S] Cluster N1a for Electron Transfer and Assembly of Escherichia coli Respiratory Complex I. Biochemistry 2017; 56:2770-2778. [DOI: 10.1021/acs.biochem.6b01058] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Katerina Dörner
- Institut
für Biochemie, Albert-Ludwigs-Universität, Albertstraße 21, 79104 Freiburg, Germany
| | - Marta Vranas
- Spemann
Graduate School of Biology and Medicine (SGBM), Albert-Ludwigs-University, Freiburg, Germany
| | - Johannes Schimpf
- Institut
für Biochemie, Albert-Ludwigs-Universität, Albertstraße 21, 79104 Freiburg, Germany
| | - Isabella R. Straub
- Institut
für Biochemie, Albert-Ludwigs-Universität, Albertstraße 21, 79104 Freiburg, Germany
| | - Jo Hoeser
- Institut
für Biochemie, Albert-Ludwigs-Universität, Albertstraße 21, 79104 Freiburg, Germany
| | - Thorsten Friedrich
- Spemann
Graduate School of Biology and Medicine (SGBM), Albert-Ludwigs-University, Freiburg, Germany
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Kublanov IV, Sigalova OM, Gavrilov SN, Lebedinsky AV, Rinke C, Kovaleva O, Chernyh NA, Ivanova N, Daum C, Reddy TBK, Klenk HP, Spring S, Göker M, Reva ON, Miroshnichenko ML, Kyrpides NC, Woyke T, Gelfand MS, Bonch-Osmolovskaya EA. Genomic Analysis of Caldithrix abyssi, the Thermophilic Anaerobic Bacterium of the Novel Bacterial Phylum Calditrichaeota. Front Microbiol 2017; 8:195. [PMID: 28265262 PMCID: PMC5317091 DOI: 10.3389/fmicb.2017.00195] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Accepted: 01/26/2017] [Indexed: 11/13/2022] Open
Abstract
The genome of Caldithrix abyssi, the first cultivated representative of a phylum-level bacterial lineage, was sequenced within the framework of Genomic Encyclopedia of Bacteria and Archaea (GEBA) project. The genomic analysis revealed mechanisms allowing this anaerobic bacterium to ferment peptides or to implement nitrate reduction with acetate or molecular hydrogen as electron donors. The genome encoded five different [NiFe]- and [FeFe]-hydrogenases, one of which, group 1 [NiFe]-hydrogenase, is presumably involved in lithoheterotrophic growth, three other produce H2 during fermentation, and one is apparently bidirectional. The ability to reduce nitrate is determined by a nitrate reductase of the Nap family, while nitrite reduction to ammonia is presumably catalyzed by an octaheme cytochrome c nitrite reductase εHao. The genome contained genes of respiratory polysulfide/thiosulfate reductase, however, elemental sulfur and thiosulfate were not used as the electron acceptors for anaerobic respiration with acetate or H2, probably due to the lack of the gene of the maturation protein. Nevertheless, elemental sulfur and thiosulfate stimulated growth on fermentable substrates (peptides), being reduced to sulfide, most probably through the action of the cytoplasmic sulfide dehydrogenase and/or NAD(P)-dependent [NiFe]-hydrogenase (sulfhydrogenase) encoded by the genome. Surprisingly, the genome of this anaerobic microorganism encoded all genes for cytochrome c oxidase, however, its maturation machinery seems to be non-operational due to genomic rearrangements of supplementary genes. Despite the fact that sugars were not among the substrates reported when C. abyssi was first described, our genomic analysis revealed multiple genes of glycoside hydrolases, and some of them were predicted to be secreted. This finding aided in bringing out four carbohydrates that supported the growth of C. abyssi: starch, cellobiose, glucomannan and xyloglucan. The genomic analysis demonstrated the ability of C. abyssi to synthesize nucleotides and most amino acids and vitamins. Finally, the genomic sequence allowed us to perform a phylogenomic analysis, based on 38 protein sequences, which confirmed the deep branching of this lineage and justified the proposal of a novel phylum Calditrichaeota.
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Affiliation(s)
- Ilya V Kublanov
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences Moscow, Russia
| | - Olga M Sigalova
- A.A.Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences Moscow, Russia
| | - Sergey N Gavrilov
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences Moscow, Russia
| | - Alexander V Lebedinsky
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences Moscow, Russia
| | - Christian Rinke
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia QLD, Australia
| | - Olga Kovaleva
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences Moscow, Russia
| | - Nikolai A Chernyh
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences Moscow, Russia
| | | | - Chris Daum
- DOE Joint Genome Institute, Walnut Creek CA, USA
| | - T B K Reddy
- DOE Joint Genome Institute, Walnut Creek CA, USA
| | | | - Stefan Spring
- Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures Braunschweig, Germany
| | - Markus Göker
- Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures Braunschweig, Germany
| | - Oleg N Reva
- Center for Bioinformatics and Computational Biology, Department of Biochemistry, University of Pretoria Pretoria, South Africa
| | - Margarita L Miroshnichenko
- Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences Moscow, Russia
| | | | - Tanja Woyke
- DOE Joint Genome Institute, Walnut CreekCA, USA; Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, BerkeleyCA, USA
| | - Mikhail S Gelfand
- A.A.Kharkevich Institute for Information Transmission Problems, Russian Academy of SciencesMoscow, Russia; Department of Bioengineering and Bioinformatics, M.V. Lomonosov Moscow State UniversityMoscow, Russia; Skolkovo Institute of Science and TechnologyMoscow, Russia; Faculty of Computer Science, National Research University - Higher School of EconomicsMoscow, Russia
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Stiban J, So M, Kaguni LS. Iron-Sulfur Clusters in Mitochondrial Metabolism: Multifaceted Roles of a Simple Cofactor. BIOCHEMISTRY (MOSCOW) 2017; 81:1066-1080. [PMID: 27908232 DOI: 10.1134/s0006297916100059] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Iron-sulfur metabolism is essential for cellular function and is a key process in mitochondria. In this review, we focus on the structure and assembly of mitochondrial iron-sulfur clusters and their roles in various metabolic processes that occur in mitochondria. Iron-sulfur clusters are crucial in mitochondrial respiration, in which they are required for the assembly, stability, and function of respiratory complexes I, II, and III. They also serve important functions in the citric acid cycle, DNA metabolism, and apoptosis. Whereas the identification of iron-sulfur containing proteins and their roles in numerous aspects of cellular function has been a long-standing research area, that in mitochondria is comparatively recent, and it is likely that their roles within mitochondria have been only partially revealed. We review the status of the field and provide examples of other cellular iron-sulfur proteins to highlight their multifarious roles.
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Affiliation(s)
- Johnny Stiban
- Birzeit University, Department of Biology and Biochemistry, West Bank Birzeit, 627, Palestine.
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Amazing structure of respirasome: unveiling the secrets of cell respiration. Protein Cell 2016; 7:854-865. [PMID: 27743346 PMCID: PMC5205662 DOI: 10.1007/s13238-016-0329-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 09/28/2016] [Indexed: 11/02/2022] Open
Abstract
Respirasome, a huge molecular machine that carries out cellular respiration, has gained growing attention since its discovery, because respiration is the most indispensable biological process in almost all living creatures. The concept of respirasome has renewed our understanding of the respiratory chain organization, and most recently, the structure of respirasome solved by Yang's group from Tsinghua University (Gu et al. Nature 237(7622):639-643, 2016) firstly presented the detailed interactions within this huge molecular machine, and provided important information for drug design and screening. However, the study of cellular respiration went through a long history. Here, we briefly showed the detoured history of respiratory chain investigation, and then described the amazing structure of respirasome.
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Holt PJ, Efremov RG, Nakamaru-Ogiso E, Sazanov LA. Reversible FMN dissociation from Escherichia coli respiratory complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1777-1785. [PMID: 27555334 DOI: 10.1016/j.bbabio.2016.08.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 08/04/2016] [Accepted: 08/17/2016] [Indexed: 12/13/2022]
Abstract
Respiratory complex I transfers electrons from NADH to quinone, utilizing the reaction energy to translocate protons across the membrane. It is a key enzyme of the respiratory chain of many prokaryotic and most eukaryotic organisms. The reversible NADH oxidation reaction is facilitated in complex I by non-covalently bound flavin mononucleotide (FMN). Here we report that the catalytic activity of E. coli complex I with artificial electron acceptors potassium ferricyanide (FeCy) and hexaamineruthenium (HAR) is significantly inhibited in the enzyme pre-reduced by NADH. Further, we demonstrate that the inhibition is caused by reversible dissociation of FMN. The binding constant (Kd) for FMN increases from the femto- or picomolar range in oxidized complex I to the nanomolar range in the NADH reduced enzyme, with an FMN dissociation time constant of ~5s. The oxidation state of complex I, rather than that of FMN, proved critical to the dissociation. Such dissociation is not observed with the T. thermophilus enzyme and our analysis suggests that the difference may be due to the unusually high redox potential of Fe-S cluster N1a in E. coli. It is possible that the enzyme attenuates ROS production in vivo by releasing FMN under highly reducing conditions.
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Affiliation(s)
- Peter J Holt
- MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK
| | - Rouslan G Efremov
- Structural Biology Research Center, VIB, 1050 Brussels, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel (VUB), 1050 Brussels, Belgium
| | - Eiko Nakamaru-Ogiso
- Johnson Research Foundation, Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6059, United States
| | - Leonid A Sazanov
- Institute of Science and Technology Austria, Am Campus 1, A-3400 Klosterneuburg, Austria.
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Suenobu T, Shibata S, Fukuzumi S. Catalytic Formation of Hydrogen Peroxide from Coenzyme NADH and Dioxygen with a Water-Soluble Iridium Complex and a Ubiquinone Coenzyme Analogue. Inorg Chem 2016; 55:7747-54. [PMID: 27403568 DOI: 10.1021/acs.inorgchem.6b01220] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A ubiquinone coenzyme analogue (Q0: 2,3-dimethoxy-5-methyl-1,4-benzoquinone) was reduced by coenzyme NADH to yield the corresponding reduced form of Q0 (Q0H2) in the presence of a catalytic amount of a [C,N] cyclometalated organoiridium complex (1: [Ir(III)(Cp*)(4-(1H-pyrazol-1-yl-κN(2))benzoic acid-κC(3))(H2O)]2SO4) in water at ambient temperature as observed in the respiratory chain complex I (Complex I). In the catalytic cycle, the reduction of 1 by NADH produces the corresponding iridium hydride complex that in turn reduces Q0 to produce Q0H2. Q0H2 reduced dioxygen to yield hydrogen peroxide (H2O2) under slightly basic conditions. Catalytic generation of H2O2 was made possible in the reaction of O2 with NADH as the functional expression of NADH oxidase in white blood cells utilizing the redox cycle of Q0 as well as 1 for the first time in a nonenzymatic homogeneous reaction system.
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Affiliation(s)
- Tomoyoshi Suenobu
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, ALCA and SENTAN, Japan Science and Technology , Suita, Osaka 565-0871, Japan
| | - Satoshi Shibata
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, ALCA and SENTAN, Japan Science and Technology , Suita, Osaka 565-0871, Japan
| | - Shunichi Fukuzumi
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, ALCA and SENTAN, Japan Science and Technology , Suita, Osaka 565-0871, Japan.,Department of Chemistry and Nano Science, Ewha Womans University , Seoul 120-750, Korea.,Faculty of Science and Engineering, Meijo University, ALCA and SENTAN, Japan Science and Technology Agency , Nagoya, Aichi 468-0073, Japan
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Mills EL, O'Neill LA. Reprogramming mitochondrial metabolism in macrophages as an anti-inflammatory signal. Eur J Immunol 2016; 46:13-21. [PMID: 26643360 DOI: 10.1002/eji.201445427] [Citation(s) in RCA: 305] [Impact Index Per Article: 38.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 11/25/2015] [Accepted: 12/04/2015] [Indexed: 12/11/2022]
Abstract
Mitochondria are master regulators of metabolism. Mitochondria generate ATP by oxidative phosphorylation using pyruvate (derived from glucose and glycolysis) and fatty acids (FAs), both of which are oxidized in the Krebs cycle, as fuel sources. Mitochondria are also an important source of reactive oxygen species (ROS), creating oxidative stress in various contexts, including in the response to bacterial infection. Recently, complex changes in mitochondrial metabolism have been characterized in mouse macrophages in response to varying stimuli in vitro. In LPS and IFN-γ-activated macrophages (M1 macrophages), there is decreased respiration and a broken Krebs cycle, leading to accumulation of succinate and citrate, which act as signals to alter immune function. In IL-4-activated macrophages (M2 macrophages), the Krebs cycle and oxidative phosphorylation are intact and fatty acid oxidation (FAO) is also utilized. These metabolic alterations in response to the nature of the stimulus are proving to be determinants of the effector functions of M1 and M2 macrophages. Furthermore, reprogramming of macrophages from M1 to M2 can be achieved by targeting metabolic events. Here, we describe the role that metabolism plays in macrophage function in infection and immunity, and propose that reprogramming with metabolic inhibitors might be a novel therapeutic approach for the treatment of inflammatory diseases.
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Affiliation(s)
- Evanna L Mills
- Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland
| | - Luke A O'Neill
- Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland
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Sheu SY, Schlag EW, Yang DY. A model for ultra-fast charge transport in membrane proteins. Phys Chem Chem Phys 2016; 17:23088-94. [PMID: 26274051 DOI: 10.1039/c5cp01442e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Isolated proteins have recently been observed to transport charge and reactivity over very long distances with extraordinary rates and near perfect efficiencies in spite of their site. This is not the case if the peptide is in water, where the efficiency of charge hopping to the next site is reduced to approximately 2%. Here, water is not an ideal solvent for charge transport. The issue at hand is how to explain such enormous charge transfer quenching in water compared to another typical medium, namely lipid. We performed molecular dynamics simulations to computationally substantiate the novel long-distance charge transfer yield of the polypeptides in lipids. This is characterized by the charge transfer persistent-distance decay constant and not by the rate, which is seldom, if ever, measured and hence not directly addressed here. This model can encompass an extremely wide range of yields over very long distances in peptides in various media. The calculations here demonstrate the good charge transport efficiency in lipids in contrast to the poor efficiency in water. The protein charge transport also exhibits a very strong anisotropic effect in lipids. The peptide secondary structure effect of charge transfer in membranes is analyzed in contrast to that in water. These results suggest that this model can be useful for the prediction of charge transfer efficiency in various environments of interest and indicate that the charge transfer is highly efficient in membrane proteins.
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Affiliation(s)
- Sheh-Yi Sheu
- Department of Life Sciences and Institute of Genome Sciences, and Institute of Biomedical Informatics, National Yang-Ming University, Taipei 112, Taiwan.
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Fromm S, Senkler J, Eubel H, Peterhänsel C, Braun HP. Life without complex I: proteome analyses of an Arabidopsis mutant lacking the mitochondrial NADH dehydrogenase complex. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:3079-93. [PMID: 27122571 PMCID: PMC4867900 DOI: 10.1093/jxb/erw165] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The mitochondrial NADH dehydrogenase complex (complex I) is of particular importance for the respiratory chain in mitochondria. It is the major electron entry site for the mitochondrial electron transport chain (mETC) and therefore of great significance for mitochondrial ATP generation. We recently described an Arabidopsis thaliana double-mutant lacking the genes encoding the carbonic anhydrases CA1 and CA2, which both form part of a plant-specific 'carbonic anhydrase domain' of mitochondrial complex I. The mutant lacks complex I completely. Here we report extended analyses for systematically characterizing the proteome of the ca1ca2 mutant. Using various proteomic tools, we show that lack of complex I causes reorganization of the cellular respiration system. Reduced electron entry into the respiratory chain at the first segment of the mETC leads to induction of complexes II and IV as well as alternative oxidase. Increased electron entry at later segments of the mETC requires an increase in oxidation of organic substrates. This is reflected by higher abundance of proteins involved in glycolysis, the tricarboxylic acid cycle and branched-chain amino acid catabolism. Proteins involved in the light reaction of photosynthesis, the Calvin cycle, tetrapyrrole biosynthesis, and photorespiration are clearly reduced, contributing to the significant delay in growth and development of the double-mutant. Finally, enzymes involved in defense against reactive oxygen species and stress symptoms are much induced. These together with previously reported insights into the function of plant complex I, which were obtained by analysing other complex I mutants, are integrated in order to comprehensively describe 'life without complex I'.
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Affiliation(s)
- Steffanie Fromm
- Institut für Pflanzengenetik, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany Institut für Botanik, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
| | - Jennifer Senkler
- Institut für Pflanzengenetik, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
| | - Holger Eubel
- Institut für Pflanzengenetik, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
| | - Christoph Peterhänsel
- Institut für Botanik, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
| | - Hans-Peter Braun
- Institut für Pflanzengenetik, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
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Narayanan M, Sakyiama JA, Elguindy MM, Nakamaru-Ogiso E. Roles of subunit NuoL in the proton pumping coupling mechanism of NADH:ubiquinone oxidoreductase (complex I) from Escherichia coli. J Biochem 2016; 160:205-215. [PMID: 27118783 DOI: 10.1093/jb/mvw027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 03/09/2016] [Indexed: 01/13/2023] Open
Abstract
Respiratory complex I has an L-shaped structure formed by the hydrophilic arm responsible for electron transfer and the membrane arm that contains protons pumping machinery. Here, to gain mechanistic insights into the role of subunit NuoL, we investigated the effects of Mg2+, Zn2+ and the Na+/H+ antiporter inhibitor 5-(N-ethyl-N-isopropyl)-amiloride (EIPA) on proton pumping activities of various isolated NuoL mutant complex I after reconstitution into Escherichia coli double knockout (DKO) membrane vesicles lacking complex I and the NADH dehydrogenase type 2. We found that Mg2+ was critical for proton pumping activity of complex I. At 2 µM Zn2+, proton pumping of the wild-type was selectively inhibited without affecting electron transfer; no inhibition in proton pumping of D178N and D400A was observed, suggesting the involvement of these residues in Zn2+ binding. Fifteen micromolar of EIPA caused up to ∼40% decrease in the proton pumping activity of the wild-type, D303A and D400A/E, whereas no significant change was detected in D178N, indicating its possible involvement in the EIPA binding. Furthermore, when menaquinone-rich DKO membranes were used, the proton pumping efficiency in the wild-type was decreased significantly (∼50%) compared with NuoL mutants strongly suggesting that NuoL is involved in the high efficiency pumping mechanism in complex I.
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Affiliation(s)
- Madhavan Narayanan
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, 422 Curie Boulevard, Philadelphia, PA 19104, USA
| | - Joseph A Sakyiama
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, 422 Curie Boulevard, Philadelphia, PA 19104, USA
| | - Mahmoud M Elguindy
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, 422 Curie Boulevard, Philadelphia, PA 19104, USA
| | - Eiko Nakamaru-Ogiso
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, 422 Curie Boulevard, Philadelphia, PA 19104, USA
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Ševčíková T, Klimeš V, Zbránková V, Strnad H, Hroudová M, Vlček Č, Eliáš M. A Comparative Analysis of Mitochondrial Genomes in Eustigmatophyte Algae. Genome Biol Evol 2016; 8:705-22. [PMID: 26872774 PMCID: PMC4824035 DOI: 10.1093/gbe/evw027] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Eustigmatophyceae (Ochrophyta, Stramenopiles) is a small algal group with species of the genus Nannochloropsis being its best studied representatives. Nuclear and organellar genomes have been recently sequenced for several Nannochloropsis spp., but phylogenetically wider genomic studies are missing for eustigmatophytes. We sequenced mitochondrial genomes (mitogenomes) of three species representing most major eustigmatophyte lineages, Monodopsis sp. MarTras21, Vischeria sp. CAUP Q 202 and Trachydiscus minutus, and carried out their comparative analysis in the context of available data from Nannochloropsis and other stramenopiles, revealing a number of noticeable findings. First, mitogenomes of most eustigmatophytes are highly collinear and similar in the gene content, but extensive rearrangements and loss of three otherwise ubiquitous genes happened in the Vischeria lineage; this correlates with an accelerated evolution of mitochondrial gene sequences in this lineage. Second, eustigmatophytes appear to be the only ochrophyte group with the Atp1 protein encoded by the mitogenome. Third, eustigmatophyte mitogenomes uniquely share a truncated nad11 gene encoding only the C-terminal part of the Nad11 protein, while the N-terminal part is encoded by a separate gene in the nuclear genome. Fourth, UGA as a termination codon and the cognate release factor mRF2 were lost from mitochondria independently by the Nannochloropsis and T. minutus lineages. Finally, the rps3 gene in the mitogenome of Vischeria sp. is interrupted by the UAG codon, but the genome includes a gene for an unusual tRNA with an extended anticodon loop that we speculate may serve as a suppressor tRNA to properly decode the rps3 gene.
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Affiliation(s)
- Tereza Ševčíková
- Department of Biology and Ecology & Institute of Environmental Technologies, Faculty of Science, University of Ostrava, Czech Republic
| | - Vladimír Klimeš
- Department of Biology and Ecology & Institute of Environmental Technologies, Faculty of Science, University of Ostrava, Czech Republic
| | - Veronika Zbránková
- Department of Biology and Ecology & Institute of Environmental Technologies, Faculty of Science, University of Ostrava, Czech Republic
| | - Hynek Strnad
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Miluše Hroudová
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Čestmír Vlček
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Marek Eliáš
- Department of Biology and Ecology & Institute of Environmental Technologies, Faculty of Science, University of Ostrava, Czech Republic
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