1
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Flores L, Shene C. Single Amino Acids as Sole Nitrogen Source for the Production of Lipids and Coenzyme Q by Thraustochytrium sp. RT2316-16. Microorganisms 2024; 12:1428. [PMID: 39065196 PMCID: PMC11279195 DOI: 10.3390/microorganisms12071428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2024] [Revised: 07/08/2024] [Accepted: 07/11/2024] [Indexed: 07/28/2024] Open
Abstract
This work analyzes the production of total lipids and the content of CoQ9 and CoQ10 in the biomass of Thraustochytrium sp. RT2316-16 grown in media containing a single amino acid at a concentration of 1 g L-1 as the sole nitrogen source; glucose (5 g L-1) was used as the carbon source. Biomass concentration and the content of total lipids and CoQ were determined as a function of the incubation time; ten amino acids were evaluated. The final concentration of the total biomass was found to be between 2.2 ± 0.1 (aspartate) and 3.9 ± 0.1 g L-1 (glutamate). The biomass grown in media containing glutamate, serine or phenylalanine reached a content of total lipids higher than 20% of the cell dry weight (DW) after 72, 60 and 72 h of incubation, respectively. The highest contents of CoQ9 (39.0 ± 0.7 µg g-1 DW) and CoQ10 (167.4 ± 3.4 mg g-1 DW) in the biomass of the thraustochytrid were obtained when glutamate and cysteine were used as the nitrogen source, respectively. Fatty acid oxidation, which decreased the total lipid content during the first 12 h of incubation, and the oxidation of hydrogen sulfide when cysteine was the nitrogen source, might be related to the content of CoQ10 in the biomass of the thraustochytrid.
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Affiliation(s)
| | - Carolina Shene
- Department of Chemical Engineering, Center of Food Biotechnology and Bioseparations, BIOREN, and Centre of Biotechnology and Bioengineering (CeBiB), Universidad de La Frontera, Temuco 4780000, Chile;
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2
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Benchoam D, Cuevasanta E, Roman JV, Banerjee R, Alvarez B. Acidity of persulfides and its modulation by the protein environments in sulfide quinone oxidoreductase and thiosulfate sulfurtransferase. J Biol Chem 2024; 300:107149. [PMID: 38479599 PMCID: PMC11039317 DOI: 10.1016/j.jbc.2024.107149] [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: 10/22/2023] [Revised: 02/12/2024] [Accepted: 02/28/2024] [Indexed: 04/23/2024] Open
Abstract
Persulfides (RSSH/RSS-) participate in sulfur metabolism and are proposed to transduce hydrogen sulfide (H2S) signaling. Their biochemical properties are poorly understood. Herein, we studied the acidity and nucleophilicity of several low molecular weight persulfides using the alkylating agent, monobromobimane. The different persulfides presented similar pKa values (4.6-6.3) and pH-independent rate constants (3.2-9.0 × 103 M-1 s-1), indicating that the substituents in persulfides affect properties to a lesser extent than in thiols because of the larger distance to the outer sulfur. The persulfides had higher reactivity with monobromobimane than analogous thiols and putative thiols with the same pKa, providing evidence for the alpha effect (enhanced nucleophilicity by the presence of a contiguous atom with high electron density). Additionally, we investigated two enzymes from the human mitochondrial H2S oxidation pathway that form catalytic persulfide intermediates, sulfide quinone oxidoreductase and thiosulfate sulfurtransferase (TST, rhodanese). The pH dependence of the activities of both enzymes was measured using sulfite and/or cyanide as sulfur acceptors. The TST half-reactions were also studied by stopped-flow fluorescence spectroscopy. Both persulfidated enzymes relied on protonated groups for reaction with the acceptors. Persulfidated sulfide quinone oxidoreductase appeared to have a pKa of 7.8 ± 0.2. Persulfidated TST presented a pKa of 9.38 ± 0.04, probably due to a critical active site residue rather than the persulfide itself. The TST thiol reacted in the anionic state with thiosulfate, with an apparent pKa of 6.5 ± 0.1. Overall, our study contributes to a fundamental understanding of persulfide properties and their modulation by protein environments.
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Affiliation(s)
- Dayana Benchoam
- Laboratorio de Enzimología, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Centro de Investigaciones Biomédicas (CEINBIO), Universidad de la República, Montevideo, Uruguay; Graduate Program in Chemistry, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Ernesto Cuevasanta
- Laboratorio de Enzimología, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Centro de Investigaciones Biomédicas (CEINBIO), Universidad de la República, Montevideo, Uruguay; Unidad de Bioquímica Analítica, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Laboratorio de Fisicoquímica Biológica, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Joseph V Roman
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Beatriz Alvarez
- Laboratorio de Enzimología, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Centro de Investigaciones Biomédicas (CEINBIO), Universidad de la República, Montevideo, Uruguay.
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3
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Feng S, Huang X, Tang D, Liu X, Ouyang L, Yang D, Wang K, Liao B, Qi S. The crystal structure of human ferroptosis suppressive protein 1 in complex with flavin adenine dinucleotide and nicotinamide adenine nucleotide. MedComm (Beijing) 2024; 5:e479. [PMID: 38414669 PMCID: PMC10896247 DOI: 10.1002/mco2.479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 01/01/2024] [Accepted: 01/05/2024] [Indexed: 02/29/2024] Open
Abstract
Ferroptosis is a recently discovered form of regulated cell death characterized by its distinct dependence on iron and the peroxidation of lipids within cellular membranes. Ferroptosis plays a crucial role in physiological and pathological situations and has attracted the attention of numerous scientists. Ferroptosis suppressive protein 1 (FSP1) is one of the main regulators that negatively regulates ferroptosis through the GPX4-independent FSP1-CoQ10-NAD(P)H axis and is a potential therapeutic target for ferroptosis-related diseases. However, the crystal structure of FSP1 has not been resolved, which hinders the development of therapeutic strategies targeting FSP1. To unravel this puzzle, we purified the human FSP1 (hFSP1) protein using the baculovirus eukaryotic cell expression system and solved its crystal structure at a resolution of 1.75 Å. Furthermore, we evaluated the oxidoreductase activity of hFSP1 with NADH as the substrate and identified E156 as the key amino acid in maintaining hFSP1 activity. Interestingly, our results indicated that hFSP1 exists and functions in a monomeric state. Mutagenesis analysis revealed the critical role of the C-terminal domain in the binding of substrate. These findings significantly enhance our understanding of the functional mechanism of FSP1 and provide a precise model for further drug development.
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Affiliation(s)
- Shijian Feng
- Department of Urology and Institute of Urology (Laboratory of Reconstructive Urology)State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, College of Life Sciences, Sichuan UniversityChengduChina
| | - Xiaofang Huang
- Department of Urology and Institute of Urology (Laboratory of Reconstructive Urology)State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, College of Life Sciences, Sichuan UniversityChengduChina
| | - Dan Tang
- Department of Urology and Institute of Urology (Laboratory of Reconstructive Urology)State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, College of Life Sciences, Sichuan UniversityChengduChina
| | - Xiaoyu Liu
- Department of Urology and Institute of Urology (Laboratory of Reconstructive Urology)State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, College of Life Sciences, Sichuan UniversityChengduChina
| | - Liang Ouyang
- Department of Urology and Institute of Urology (Laboratory of Reconstructive Urology)State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, College of Life Sciences, Sichuan UniversityChengduChina
| | - Dehua Yang
- The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of SciencesShanghaiChina
| | - Kunjie Wang
- Department of Urology and Institute of Urology (Laboratory of Reconstructive Urology)State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, College of Life Sciences, Sichuan UniversityChengduChina
| | - Banghua Liao
- Department of Urology and Institute of Urology (Laboratory of Reconstructive Urology)State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, College of Life Sciences, Sichuan UniversityChengduChina
| | - Shiqian Qi
- Department of Urology and Institute of Urology (Laboratory of Reconstructive Urology)State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, College of Life Sciences, Sichuan UniversityChengduChina
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Griffiths KK, Wang A, Jonas EA, Levy RJ. Sulfide quinone oxidoreductase contributes to voltage sensing of the mitochondrial permeability transition pore. FASEB J 2024; 38:e23494. [PMID: 38376922 PMCID: PMC11082757 DOI: 10.1096/fj.202301280r] [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: 06/26/2023] [Revised: 12/18/2023] [Accepted: 02/02/2024] [Indexed: 02/21/2024]
Abstract
Pathological opening of the mitochondrial permeability transition pore (mPTP) is implicated in the pathogenesis of many disease processes such as myocardial ischemia, traumatic brain injury, Alzheimer's disease, and diabetes. While we have gained insight into mPTP biology over the last several decades, the lack of translation of this knowledge into successful clinical therapies underscores the need for continued investigation and use of different approaches to identify novel regulators of the mPTP with the hope of elucidating new therapeutic targets. Although the mPTP is known to be a voltage-gated channel, the identity of its voltage sensor remains unknown. Here we found decreased gating potential of the mPTP and increased expression and activity of sulfide quinone oxidoreductase (SQOR) in newborn Fragile X syndrome (FXS) mouse heart mitochondria, a model system of coenzyme Q excess and relatively decreased mPTP open probability. We further found that pharmacological inhibition and genetic silencing of SQOR increased mPTP open probability in vitro in adult murine cardiac mitochondria and in the isolated-perfused heart, likely by interfering with voltage sensing. Thus, SQOR is proposed to contribute to voltage sensing by the mPTP and may be a component of the voltage sensing apparatus that modulates the gating potential of the mPTP.
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Affiliation(s)
- Keren K. Griffiths
- Department of Anesthesiology, Columbia University Medical Center, NY, USA 10032
| | - Aili Wang
- Department of Anesthesiology, Columbia University Medical Center, NY, USA 10032
| | - Elizabeth A. Jonas
- Section of Endocrinology, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Richard J. Levy
- Department of Anesthesiology, Columbia University Medical Center, NY, USA 10032
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5
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Urrutia PJ, Bórquez DA. Expanded bioinformatic analysis of Oximouse dataset reveals key putative processes involved in brain aging and cognitive decline. Free Radic Biol Med 2023; 207:200-211. [PMID: 37473875 DOI: 10.1016/j.freeradbiomed.2023.07.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/11/2023] [Accepted: 07/17/2023] [Indexed: 07/22/2023]
Abstract
The theory that aging is driven by the damage produced by reactive oxygen species (ROS) derived from oxidative metabolism dominated geroscience studies during the second half of the 20th century. However, increasing evidence that ROS also plays a key role in the physiological regulation of numerous processes through the reversible oxidation of cysteine residues in proteins, has challenged this notion. Currently, the scope of redox signaling has reached proteomic dimensions through mass spectrometry techniques. Here, we perform a comprehensive bioinformatics analysis of cysteine oxidation changes during mouse brain aging, using the quantitative data provided in the Oximouse dataset. Interestingly, our unbiased analysis identified hundreds of putative cysteine redox switches covering several pathways previously associated with aging. These include the ubiquitin-proteasome pathway and one-carbon metabolism (folate cycle, methionine cycle, transsulfuration and polyamine pathways). Surprisingly, cysteine oxidation changes are enriched in synaptic proteins in a highly asymmetric distribution: while postsynaptic proteins tend to increase cysteine oxidation with age, the opposite occurs for presynaptic proteins. Additionally, cysteine oxidation changes during aging are associated with proteins involved in the regulation of the mitochondrial transition pore opening and synaptic calcium homeostasis. Our analysis reinforces the concept that brain aging is associated with selective changes in the oxidation state of key proteins, rather than an overall trend toward increased oxidation. Also, we provide a prioritized list of specific cysteine residues with putative impact in aging processes for future experimental validation.
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Affiliation(s)
- Pamela J Urrutia
- Institute for Nutrition & Food Technology (INTA), Universidad de Chile, El Líbano 5524, Santiago, 7830490, Chile; Geroscience Center for Brain Health and Metabolism, Santiago, 7800003, Chile
| | - Daniel A Bórquez
- Laboratory of Cell Signaling & Bioinformatics, Center for Biomedical Research, Faculty of Medicine, Universidad Diego Portales, Ejército Libertador 141, Santiago, 8370007, Chile.
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6
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Hanna D, Kumar R, Banerjee R. A Metabolic Paradigm for Hydrogen Sulfide Signaling via Electron Transport Chain Plasticity. Antioxid Redox Signal 2023; 38:57-67. [PMID: 35651282 PMCID: PMC9885546 DOI: 10.1089/ars.2022.0067] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 05/24/2022] [Indexed: 02/03/2023]
Abstract
Significance: A burgeoning literature has attributed varied physiological effects to hydrogen sulfide (H2S), which is a product of eukaryotic sulfur amino acid metabolism. Protein persulfidation represents a major focus of studies elucidating the mechanism underlying H2S signaling. On the contrary, the capacity of H2S to induce reductive stress by targeting the electron transport chain (ETC) and signal by reprogramming redox metabolism has only recently begun to be elucidated. Recent Advances: In contrast to the nonspecific reaction of H2S with oxidized cysteines to form protein persulfides, its inhibition of complex IV represents a specific mechanism of action. Studies on the dual impact of H2S as an ETC substrate and an inhibitor have led to the exciting discovery of ETC plasticity and the use of fumarate as a terminal electron acceptor. H2S oxidation combined with complex IV targeting generates mitochondrial reductive stress, which is signaled through the metabolic network, leading to increased aerobic glycolysis, glutamine-dependent reductive carboxylation, and lipogenesis. Critical Issues: Insights into H2S-induced metabolic reprogramming are ushering in a paradigm shift for understanding the mechanism of its cellular action. It will be critical to reevaluate the physiological effects of H2S, for example, cytoprotection against ischemia-reperfusion injury, through the framework of metabolic reprogramming and ETC remodeling by H2S. Future Directions: The metabolic ramifications of H2S in other cellular compartments, for example, the endoplasmic reticulum and the nucleus, as well as the intersections between hypoxia and H2S signaling are important future directions that merit elucidation. Antioxid. Redox Signal. 38, 57-67.
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Affiliation(s)
- David Hanna
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Roshan Kumar
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
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7
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Stummer N, Weghuber D, Feichtinger RG, Huber S, Mayr JA, Kofler B, Neureiter D, Klieser E, Hochmann S, Lauth W, Schneider AM. Hydrogen Sulfide Metabolizing Enzymes in the Intestinal Mucosa in Pediatric and Adult Inflammatory Bowel Disease. Antioxidants (Basel) 2022; 11:2235. [PMID: 36421421 PMCID: PMC9686699 DOI: 10.3390/antiox11112235] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/02/2022] [Accepted: 11/08/2022] [Indexed: 08/27/2023] Open
Abstract
Hydrogen sulfide (H2S) is a toxic gas that has important regulatory functions. In the colon, H2S can be produced and detoxified endogenously. Both too little and too much H2S exposure are associated with inflammatory bowel disease (IBD), a chronic intestinal disease mainly classified as Crohn's disease (CD) and ulcerative colitis (UC). As the pathogenesis of IBD remains elusive, this study's aim was to investigate potential differences in the expression of H2S-metabolizing enzymes in normal aging and IBD. Intestinal mucosal biopsies of 25 adults and 22 children with IBD along with those of 26 healthy controls were stained immunohistochemically for cystathionine-γ-lyase (CSE), 3-mercapto-sulfurtransferase (3-MST), ethylmalonic encephalopathy 1 protein (ETHE1), sulfide:quinone oxidoreductase (SQOR) and thiosulfate sulfurtransferase (TST). Expression levels were calculated by multiplication of the staining intensity and percentage of positively stained cells. Healthy adults showed an overall trend towards lower expression of H2S-metabolizing enzymes than healthy children. Adults with IBD also tended to have lower expression compared to controls. A similar trend was seen in the enzyme expression of children with IBD compared to controls. These results indicate an age-related decrease in the expression of H2S-metabolizing enzymes and a dysfunctional H2S metabolism in IBD, which was less pronounced in children.
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Affiliation(s)
- Nathalie Stummer
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
| | - Daniel Weghuber
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
| | - René G. Feichtinger
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
| | - Sara Huber
- Research Program for Receptor Biochemistry and Tumor Metabolism, Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
| | - Johannes A. Mayr
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
| | - Barbara Kofler
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
- Research Program for Receptor Biochemistry and Tumor Metabolism, Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
| | - Daniel Neureiter
- Institute of Pathology, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
| | - Eckhard Klieser
- Institute of Pathology, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
| | - Sarah Hochmann
- Cell Therapy Institute, Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University (PMU), 5020 Salzburg, Austria
| | - Wanda Lauth
- Department of Mathematics, Paris Lodron University, 5020 Salzburg, Austria
| | - Anna M. Schneider
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), 5020 Salzburg, Austria
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8
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Miklovics N, Duzs Á, Balogh F, Paragi G, Rákhely G, Tóth A. Quinone binding site in a type VI sulfide:quinone oxidoreductase. Appl Microbiol Biotechnol 2022; 106:7505-7517. [PMID: 36219222 DOI: 10.1007/s00253-022-12202-8] [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: 07/01/2022] [Revised: 09/16/2022] [Accepted: 09/21/2022] [Indexed: 11/26/2022]
Abstract
Monotopic membrane-bound flavoproteins, sulfide:quinone oxidoreductases (SQRs), have a variety of physiological functions, including sulfide detoxification. SQR enzymes are classified into six groups. SQRs use the flavin adenine dinucleotide (FAD) cofactor to transfer electrons from sulfide to quinone. A type VI SQR of the photosynthetic purple sulfur bacterium, Thiocapsa roseopersicina (TrSqrF), has been previously characterized, and the mechanism of sulfide oxidation has been proposed. This paper reports the characterization of quinone binding site (QBS) of TrSqrF composed of conserved aromatic and apolar amino acids. Val331, Ile333, and Phe366 were identified near the benzoquinone ring of enzyme-bound decylubiquinone (dUQ) using the TrSqrF homology model. In silico analysis revealed that Val331 and Ile333 alternately connected with the quinone head group via hydrogen bonds, and Phe366 and Trp369 bound the quinones via hydrophobic interactions. TrSqrF variants containing alanine (V331A, I333A, F366A) and aromatic amino acid (V331F, I333F, F366Y), as well as a C-terminal α-helix deletion (CTD) mutant were generated. These amino acids are critical for quinone binding and, thus, catalysis. Spectroscopic analyses proved that all mutants contained FAD. I333F replacement resulted in the lack of the charge transfer complex. In summary, the interactions described above maintain the quinone molecule's head in an optimal position for direct electron transfer from FAD. Surprisingly, the CTD mutant retained a relatively high level of specific activity while remaining membrane-anchored. This is a unique study because it focuses on the QBS and the oxidative stage of a type VI sulfide-dependent quinone reduction. KEY POINTS: • V331, I333, F366, and W369 were shown to interact with decylubiquinone in T. roseopersicina SqrF • These amino acids are involved in proper positioning of quinones next to FAD • I333 is essential in formation of a charge transfer complex from FAD to quinone.
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Affiliation(s)
- Nikolett Miklovics
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary
- Department of Biotechnology, University of Szeged, Szeged, Hungary
- Doctoral School in Biology, University of Szeged, Szeged, Hungary
| | - Ágnes Duzs
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary
- Department of Biotechnology, University of Szeged, Szeged, Hungary
| | - Fanni Balogh
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary
- Department of Biotechnology, University of Szeged, Szeged, Hungary
| | - Gábor Paragi
- Institute of Physics, University of Pécs, Pécs, Hungary
- Department of Theoretical Physics, University of Szeged, Szeged, Hungary
| | - Gábor Rákhely
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary.
- Department of Biotechnology, University of Szeged, Szeged, Hungary.
| | - András Tóth
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary
- Department of Biotechnology, University of Szeged, Szeged, Hungary
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9
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Desai HS, Yan T, Yu F, Sun AW, Villanueva M, Nesvizhskii AI, Backus KM. SP3-Enabled Rapid and High Coverage Chemoproteomic Identification of Cell-State-Dependent Redox-Sensitive Cysteines. Mol Cell Proteomics 2022; 21:100218. [PMID: 35219905 PMCID: PMC9010637 DOI: 10.1016/j.mcpro.2022.100218] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 02/17/2022] [Accepted: 02/22/2022] [Indexed: 02/07/2023] Open
Abstract
Proteinaceous cysteine residues act as privileged sensors of oxidative stress. As reactive oxygen and nitrogen species have been implicated in numerous pathophysiological processes, deciphering which cysteines are sensitive to oxidative modification and the specific nature of these modifications is essential to understanding protein and cellular function in health and disease. While established mass spectrometry-based proteomic platforms have improved our understanding of the redox proteome, the widespread adoption of these methods is often hindered by complex sample preparation workflows, prohibitive cost of isotopic labeling reagents, and requirements for custom data analysis workflows. Here, we present the SP3-Rox redox proteomics method that combines tailored low cost isotopically labeled capture reagents with SP3 sample cleanup to achieve high throughput and high coverage proteome-wide identification of redox-sensitive cysteines. By implementing a customized workflow in the free FragPipe computational pipeline, we achieve accurate MS1-based quantitation, including for peptides containing multiple cysteine residues. Application of the SP3-Rox method to cellular proteomes identified cysteines sensitive to the oxidative stressor GSNO and cysteine oxidation state changes that occur during T cell activation. High-coverage Cys oxidation state quantification using custom isotopic probes. FragPipe-IonQuant accurately quantifies Cys labeling comparably to Skyline. PTMProphet enables site-of-labeling localization for multi-Cys–containing peptides. SP3-Rox identifies changes in Cys oxidation during T cell activation.
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Affiliation(s)
- Heta S Desai
- Biological Chemistry Department, David Geffen School of Medicine, UCLA, Los Angeles, California, USA; Molecular Biology Institute, UCLA, Los Angeles, California, USA
| | - Tianyang Yan
- Biological Chemistry Department, David Geffen School of Medicine, UCLA, Los Angeles, California, USA; Department of Chemistry and Biochemistry, UCLA, Los Angeles, California, USA
| | - Fengchao Yu
- Department of Pathology, University of Michigan, Ann Arbor, Michigan, USA
| | - Alexander W Sun
- Biological Chemistry Department, David Geffen School of Medicine, UCLA, Los Angeles, California, USA
| | - Miranda Villanueva
- Biological Chemistry Department, David Geffen School of Medicine, UCLA, Los Angeles, California, USA; Molecular Biology Institute, UCLA, Los Angeles, California, USA
| | - Alexey I Nesvizhskii
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA; Department of Pathology, University of Michigan, Ann Arbor, Michigan, USA
| | - Keriann M Backus
- Biological Chemistry Department, David Geffen School of Medicine, UCLA, Los Angeles, California, USA; Department of Chemistry and Biochemistry, UCLA, Los Angeles, California, USA; Molecular Biology Institute, UCLA, Los Angeles, California, USA; DOE Institute for Genomics and Proteomics, UCLA, Los Angeles, California, USA; Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, California, USA; Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, UCLA, Los Angeles, California, USA.
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10
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Olson KR, Clear KJ, Derry PJ, Gao Y, Ma Z, Wu G, Kent TA, Straub KD. Coenzyme Q 10 and related quinones oxidize H 2S to polysulfides and thiosulfate. Free Radic Biol Med 2022; 182:119-131. [PMID: 35202787 DOI: 10.1016/j.freeradbiomed.2022.02.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 02/03/2022] [Accepted: 02/18/2022] [Indexed: 12/11/2022]
Abstract
In the canonical pathway for mitochondrial H2S oxidation electrons are transferred from sulfide:quinone oxidoreductase (SQR) to complex III via ubiquinone (CoQ10). We previously observed that a number of quinones directly oxidize H2S and we hypothesize that CoQ10 may have similar properties. Here we examine H2S oxidation by CoQ10 and more hydrophilic, truncated forms, CoQ1 and CoQ0, in buffer using H2S and polysulfide fluorophores (AzMC and SSP4), silver nanoparticles to measure thiosulfate (H2S2O3), mass spectrometry to identify polysulfides and O2-sensitive optodes to measure O2 consumption. We show that all three quinones concentration-dependently catalyze the oxidization of H2S to polysulfides and thiosulfate in buffer with the potency CoQ0>CoQ1>CoQ10 and that CoQ0 specifically oxidizes H2S to per-polysulfides, H2S2,3,4. These reactions consume and require oxygen and are augmented by addition of SOD suggesting that the quinones, not superoxide, oxidize H2S. Related quinones, MitoQ, menadione and idebenone, oxidize H2S in similar reactions. Exogenous CoQ0 decreases cellular H2S and increases polysulfides and thiosulfate production and this is also O2-dependent, suggesting that the quinone has similar effects on sulfur metabolism in cells. Collectively, these results suggest an additional endogenous mechanism for H2S metabolism and a potential therapeutic approach in H2S-related metabolic disorders.
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Affiliation(s)
- Kenneth R Olson
- Indiana University School of Medicine - South Bend Center, South Bend, IN, 46617, USA; Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, 46556, USA.
| | - Kasey J Clear
- Department of Chemistry and Biochemistry, Indiana University South Bend, South Bend, IN, 46615, USA
| | - Paul J Derry
- Department of Internal Medicine, University of Texas - McGovern Medical School at Houston, Houston, TX, 77030, USA
| | - Yan Gao
- Indiana University School of Medicine - South Bend Center, South Bend, IN, 46617, USA
| | - Zhilin Ma
- Indiana University School of Medicine - South Bend Center, South Bend, IN, 46617, USA; Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Gang Wu
- Department of Internal Medicine, University of Texas - McGovern Medical School at Houston, Houston, TX, 77030, USA
| | - Thomas A Kent
- Center for Genomics and Precision Medicine, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX, 77030, USA; Department of Chemistry, Rice University, Houston, TX, 77005, United States; Stanley H. Appel Department of Neurology, Houston Methodist Hospital and Research Institute, 6560 Fannin Street, Houston, TX, 77030, United States
| | - Karl D Straub
- Central Arkansas Veteran's Healthcare System, Little Rock, AR, 72205, USA; Departments of Medicine and Biochemistry, University of Arkansas for Medical Sciences, Little Rock, AR, 72202, USA
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11
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Baugh SDP, Jackson MR, Rashad AA, Reitz AB, Lam PYS, Jorns MS. Synthesis and evaluation of potent novel inhibitors of human sulfide:quinone oxidoreductase. Bioorg Med Chem Lett 2021; 54:128443. [PMID: 34763081 DOI: 10.1016/j.bmcl.2021.128443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/20/2021] [Accepted: 11/02/2021] [Indexed: 10/19/2022]
Abstract
Here we report the first small-molecule inhibitors of human sulfide:quinone oxidoreductase (SQOR) that decrease the rate of breakdown of hydrogen sulfide (H2S), a potent cardioprotective signaling molecule. SQOR is a mitochondrial membrane-bound protein that catalyzes a two-electron oxidation of H2S to sulfane sulfur (S0), using glutathione (or sulfite) and coenzyme Q (CoQ) as S0 and electron acceptor, respectively. Inhibition of SQOR may constitute a new approach for the treatment of heart failure with reduced ejection fraction. Starting from top hits identified in a high-throughput screen, we conducted SAR development guided by docking of lead candidates into our crystal structure of SQOR. We identified potent SQOR inhibitors such as 19 which has an IC50 of 29 nM for SQOR inhibition and favorable pharmacokinetic and ADME properties required for in vivo efficacy testing.
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Affiliation(s)
- Simon D P Baugh
- Fox Chase Chemical Diversity Center, Inc., Doylestown, PA 18902, USA
| | - Michael R Jackson
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Adel Ahmed Rashad
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Allen B Reitz
- Fox Chase Chemical Diversity Center, Inc., Doylestown, PA 18902, USA
| | - Patrick Y S Lam
- Fox Chase Chemical Diversity Center, Inc., Doylestown, PA 18902, USA
| | - Marilyn Schuman Jorns
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA.
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12
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The pathway of sulfide oxidation to octasulfur globules in the cytoplasm of aerobic bacteria. Appl Environ Microbiol 2021; 88:e0194121. [PMID: 34878813 DOI: 10.1128/aem.01941-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sulfur-oxidizing bacteria can oxidize hydrogen sulfide (H2S) to produce sulfur globules. Although the process is common, the pathway is unclear. In recombinant Escherichia coli and wild-type Corynebacterium vitaeruminis DSM20294 with SQR but no enzymes to oxidize zero valence sulfur, SQR oxidized H2S into short-chain inorganic polysulfide (H2Sn, n≥2) and organic polysulfide (RSnH, n≥2), which reacted with each other to form long-chain GSnH (n≥2) and H2Sn before producing octasulfur (S8), the main component of elemental sulfur. GSnH also reacted with GSH to form GSnG (n≥2) and H2S; H2S was again oxidized by SQR. After GSH was depleted, SQR simply oxidized H2S to H2Sn, which spontaneously generated S8. S8 aggregated into sulfur globules in the cytoplasm. The results highlight the process of sulfide oxidation to S8 globules in the bacterial cytoplasm and demonstrate the potential of using heterotrophic bacteria with SQR to convert toxic H2S into relatively benign S8 globules. IMPORTANCE Our results support a process of H2S oxidation to produce octasulfur globules via SQR catalysis and spontaneous reactions in the bacterial cytoplasm. Since the process is an important event in geochemical cycling, a better understanding facilitates further studies and provides theoretical support for using heterotrophic bacteria with SQR to oxidize toxic H2S into sulfur globules for recovery.
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13
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Olson KR. A Case for Hydrogen Sulfide Metabolism as an Oxygen Sensing Mechanism. Antioxidants (Basel) 2021; 10:antiox10111650. [PMID: 34829521 PMCID: PMC8615108 DOI: 10.3390/antiox10111650] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/08/2021] [Accepted: 10/13/2021] [Indexed: 12/30/2022] Open
Abstract
The ability to detect oxygen availability is a ubiquitous attribute of aerobic organisms. However, the mechanism(s) that transduce oxygen concentration or availability into appropriate physiological responses is less clear and often controversial. This review will make the case for oxygen-dependent metabolism of hydrogen sulfide (H2S) and polysulfides, collectively referred to as reactive sulfur species (RSS) as a physiologically relevant O2 sensing mechanism. This hypothesis is based on observations that H2S and RSS metabolism is inversely correlated with O2 tension, exogenous H2S elicits physiological responses identical to those produced by hypoxia, factors that affect H2S production or catabolism also affect tissue responses to hypoxia, and that RSS efficiently regulate downstream effectors of the hypoxic response in a manner consistent with a decrease in O2. H2S-mediated O2 sensing is then compared to the more generally accepted reactive oxygen species (ROS) mediated O2 sensing mechanism and a number of reasons are offered to resolve some of the confusion between the two.
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Affiliation(s)
- Kenneth R Olson
- Department of Physiology, Indiana University School of Medicine-South Bend, South Bend, IN 46617, USA
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14
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Structural perspectives on H 2S homeostasis. Curr Opin Struct Biol 2021; 71:27-35. [PMID: 34214926 DOI: 10.1016/j.sbi.2021.05.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/05/2021] [Accepted: 05/23/2021] [Indexed: 11/21/2022]
Abstract
The enzymes involved in H2S homeostasis regulate its production from sulfur-containing amino acids and its oxidation to thiosulfate and sulfate. Two gatekeepers in this homeostatic circuit are cystathionine beta-synthase, which commits homocysteine to cysteine, and sulfide quinone oxidoreductase, which commits H2S to oxidation via a mitochondrial pathway. Inborn errors at either locus affect sulfur metabolism, increasing homocysteine-derived H2S synthesis in the case of CBS deficiency and reducing complex IV activity in the case of SQOR deficiency. In this review, we focus on structural perspectives on the reaction mechanisms and regulation of these two enzymes, which are key to understanding H2S homeostasis in health and its dysregulation and potential targeting in disease.
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15
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Jackson MR, Cox KD, Baugh SDP, Wakeen L, Rashad AA, Lam PYS, Polyak B, Jorns MS. Discovery of a first-in-class inhibitor of sulfide:quinone oxidoreductase that protects against adverse cardiac remodeling and heart failure. Cardiovasc Res 2021; 118:1771-1784. [PMID: 34132787 DOI: 10.1093/cvr/cvab206] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 06/14/2021] [Indexed: 12/27/2022] Open
Abstract
AIMS Hydrogen sulfide (H2S) is a potent signaling molecule that activates diverse cardioprotective pathways by posttranslational modification (persulfidation) of cysteine residues in upstream protein targets. Heart failure patients with reduced ejection fraction (HFrEF) exhibit low levels of H2S. Sulfide: quinone oxidoreductase (SQOR) catalyzes the first irreversible step in the metabolism of H2S and plays a key role in regulating H2S-mediated signaling. Our aim here was to discover a first-in-class inhibitor of human SQOR and evaluate its cardioprotective effect in an animal model of HFrEF. METHODS AND RESULTS We identified a potent inhibitor of human SQOR (STI1, IC50 = 29 nM) by high-throughput screening of a small-molecule library, followed by focused medicinal chemistry optimization and structure-based design. STI1 is a competitive inhibitor that binds with high selectivity to the coenzyme Q-binding pocket in SQOR. STI1 exhibited very low cytotoxicity and attenuated the hypertrophic response of neonatal rat ventricular cardiomyocytes and H9c2 cells induced by neurohormonal stressors. A mouse HFrEF model was produced by transverse aortic constriction (TAC). Treatment of TAC mice with STI1 mitigated the development of cardiomegaly, pulmonary congestion, dilatation of the left ventricle, and cardiac fibrosis and decreased the pressure gradient across the aortic constriction. Moreover, STI1 dramatically improved survival, preserved cardiac function, and prevented the progression to HFrEF by impeding the transition from compensated to decompensated left ventricle hypertrophy. CONCLUSION We demonstrate that the coenzyme Q-binding pocket in human SQOR is a druggable target and establish proof of concept for the potential of SQOR inhibitors to provide a novel therapeutic approach for the treatment of HFrEF. TRANSLATIONAL PERSPECTIVE In HFrEF there is a compelling need for new drugs that mitigate the pathological remodeling induced by injury and improve patient survival. This study identifies SQOR-inhibiting drugs as a promising first-in-class therapy for HFrEF patients. Due to the well-established protective properties of H2S-induced signaling in renal physiology and disease, this novel class of heart failure therapeutics may also address the large unmet need of therapies for approximately 50% of heart failure patients that have coexisting chronic renal dysfunction.
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Affiliation(s)
- Michael R Jackson
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, 19102, USA
| | - Kristie D Cox
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, 19102, USA
| | - Simon D P Baugh
- Fox Chase Chemical Diversity Center, Inc. Doylestown, PA, 18902, USA
| | - Luke Wakeen
- Department of Surgery, Drexel University College of Medicine, Philadelphia, PA, 19102, USA
| | - Adel A Rashad
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, 19102, USA
| | - Patrick Y S Lam
- Fox Chase Chemical Diversity Center, Inc. Doylestown, PA, 18902, USA
| | - Boris Polyak
- Department of Surgery, Drexel University College of Medicine, Philadelphia, PA, 19102, USA
| | - Marilyn Schuman Jorns
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, 19102, USA
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16
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Zhang T, Qin Z, Liu D, Wei M, Fu Z, Wang Q, Ma Y, Zhang Z. A novel transcription factor MRPS27 up-regulates the expression of sqr, a key gene of mitochondrial sulfide metabolism in echiuran worm Urechis unicinctus. Comp Biochem Physiol C Toxicol Pharmacol 2021; 243:108997. [PMID: 33549829 DOI: 10.1016/j.cbpc.2021.108997] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 01/25/2021] [Accepted: 01/27/2021] [Indexed: 12/15/2022]
Abstract
Hydrogen sulfide is a natural, widely distributed, poisonous substance and sulfide: quinone oxidoreductase (SQR) is responsible for oxidizing hydrogen sulfide to less toxic sulfur compounds. The increase of SQR mRNA level is an important mechanism for organisms to adapt to hydrogen sulfide-rich environments. However, its transcriptional regulation mechanism is not very clear. In this study, a mitochondrial 28S ribosomal protein S27 (MRPS27), which has never been reported as a transcription factor, was screened by yeast one-hybrid experiment from the echiuran worm Urechis unicinctus, a benthic organism living in marine sediments. Western blotting indicated that UuMRPS27 contents increased significantly in the nuclear extract of hindgut under exposed to 150 μM sulfide. ChIP and EMSA assays demonstrated that UuMRPS27 did bind to the sqr proximal promoter, the key binding sequence was CTAGAG (+12 to +17 of the promoter) detected by DNase I footprinting assay as well as transient transfection experiments. Furthermore, UuMRPS27, as a transcription activator, exhibited the highest transcription activity compared with other reported sqr transcription factors. Our data revealed for the first time the role of MRPS27 acting as a transcription factor which expanded the understanding of sqr transcriptional regulation in sulfide metabolism mechanism.
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Affiliation(s)
- Tingting Zhang
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Zhenkui Qin
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Danwen Liu
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Maokai Wei
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Zhong Fu
- Hebei Research Institute of Marine and Fishery Science, Qinhuangdao 066002, China
| | - Qing Wang
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Yubin Ma
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
| | - Zhifeng Zhang
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
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17
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Landry AP, Ballou DP, Banerjee R. Hydrogen Sulfide Oxidation by Sulfide Quinone Oxidoreductase. Chembiochem 2021; 22:949-960. [PMID: 33080111 PMCID: PMC7969369 DOI: 10.1002/cbic.202000661] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/19/2020] [Indexed: 02/05/2023]
Abstract
Hydrogen sulfide (H2 S) is an environmental toxin and a heritage of ancient microbial metabolism that has stimulated new interest following its discovery as a neuromodulator. While many physiological responses have been attributed to low H2 S levels, higher levels inhibit complex IV in the electron transport chain. To prevent respiratory poisoning, a dedicated set of enzymes that make up the mitochondrial sulfide oxidation pathway exists to clear H2 S. The committed step in this pathway is catalyzed by sulfide quinone oxidoreductase (SQOR), which couples sulfide oxidation to coenzyme Q10 reduction in the electron transport chain. The SQOR reaction prevents H2 S accumulation and generates highly reactive persulfide species as products; these can be further oxidized or can modify cysteine residues in proteins by persulfidation. Here, we review the kinetic and structural characteristics of human SQOR, and how its unconventional redox cofactor configuration and substrate promiscuity lead to sulfide clearance and potentially expand the signaling potential of H2 S. This dual role of SQOR makes it a promising target for H2 S-based therapeutics.
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Affiliation(s)
- Aaron P. Landry
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - David P. Ballou
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
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18
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Duzs Á, Miklovics N, Paragi G, Rákhely G, Tóth A. Insights into the catalytic mechanism of type VI sulfide:quinone oxidoreductases. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1862:148337. [PMID: 33202220 DOI: 10.1016/j.bbabio.2020.148337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 10/09/2020] [Accepted: 11/03/2020] [Indexed: 10/23/2022]
Abstract
Sulfide oxidation is catalyzed by ancient membrane-bound sulfide:quinone oxidoreductases (SQR) which are classified into six different types. For catalysis of sulfide oxidation, all SQRs require FAD cofactor and a redox-active centre in the active site, usually formed between conserved essential cysteines. SQRs of different types have variation in the number and position of cysteines, highlighting the potential for diverse catalytic mechanisms. The photosynthetic purple sulfur bacterium, Thiocapsa roseopersicina contains a type VI SQR enzyme (TrSqrF) having unusual catalytic parameters and four cysteines likely involved in the catalysis. Site-directed mutagenesis was applied to identify the role of cysteines in the catalytic process of TrSqrF. Based on biochemical and kinetic characterization of these TrSqrF variants, Cys121 is identified as crucial for enzyme activity. The cofactor is covalently bound via a heterodisulfide bridge between Cys121 and the C8M group of FAD. Mutation of another cysteine present in all SQRs (Cys332) causes remarkably decreased enzyme activity (14.6% of wild type enzyme) proving important, but non-essential role of this residue in enzyme catalysis. The sulfhydril-blocking agent, iodoacetamide can irreversibly inactivate TrSqrF but only if substrates are present and the enzyme is actively catalyzing its reaction. When the enzyme is inhibited by iodoacetamide, the FAD cofactor is released. The inhibition studies support a mechanism that entails opening and reforming of the heterodisulfide bridge during the catalytic cycle of TrSqrF. Our study thus reports the first detailed structure-function analysis of a type VI SQR enzyme which enables the proposal of a distinct mechanism of sulfide oxidation for this class.
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Affiliation(s)
- Ágnes Duzs
- Institute of Biophysics, Biological Research Centre, Temesvári krt 62., H-6726 Szeged, Hungary; Department of Biotechnology, University of Szeged, Közép fasor 52., H-6726 Szeged, Hungary
| | - Nikolett Miklovics
- Institute of Biophysics, Biological Research Centre, Temesvári krt 62., H-6726 Szeged, Hungary; Department of Biotechnology, University of Szeged, Közép fasor 52., H-6726 Szeged, Hungary; Doctoral School in Biology, University of Szeged, Közép fasor 52., H-6726 Szeged, Hungary
| | - Gábor Paragi
- Institute of Physics, University of Pécs, Ifjúság útja 6., H-7624 Pécs, Hungary; MTA-SZTE Biomimetic Systems Research Group, Department of Medical Chemistry, University of Szeged, Dóm square 8, H-6720 Szeged, Hungary
| | - Gábor Rákhely
- Institute of Biophysics, Biological Research Centre, Temesvári krt 62., H-6726 Szeged, Hungary; Department of Biotechnology, University of Szeged, Közép fasor 52., H-6726 Szeged, Hungary.
| | - András Tóth
- Institute of Biophysics, Biological Research Centre, Temesvári krt 62., H-6726 Szeged, Hungary; Department of Biotechnology, University of Szeged, Közép fasor 52., H-6726 Szeged, Hungary
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19
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Flygaard RK, Mühleip A, Tobiasson V, Amunts A. Type III ATP synthase is a symmetry-deviated dimer that induces membrane curvature through tetramerization. Nat Commun 2020; 11:5342. [PMID: 33093501 PMCID: PMC7583250 DOI: 10.1038/s41467-020-18993-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 09/24/2020] [Indexed: 01/01/2023] Open
Abstract
Mitochondrial ATP synthases form functional homodimers to induce cristae curvature that is a universal property of mitochondria. To expand on the understanding of this fundamental phenomenon, we characterized the unique type III mitochondrial ATP synthase in its dimeric and tetrameric form. The cryo-EM structure of a ciliate ATP synthase dimer reveals an unusual U-shaped assembly of 81 proteins, including a substoichiometrically bound ATPTT2, 40 lipids, and co-factors NAD and CoQ. A single copy of subunit ATPTT2 functions as a membrane anchor for the dimeric inhibitor IF1. Type III specific linker proteins stably tie the ATP synthase monomers in parallel to each other. The intricate dimer architecture is scaffolded by an extended subunit-a that provides a template for both intra- and inter-dimer interactions. The latter results in the formation of tetramer assemblies, the membrane part of which we determined to 3.1 Å resolution. The structure of the type III ATP synthase tetramer and its associated lipids suggests that it is the intact unit propagating the membrane curvature.
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Affiliation(s)
- Rasmus Kock Flygaard
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177, Stockholm, Sweden
| | - Alexander Mühleip
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177, Stockholm, Sweden
| | - Victor Tobiasson
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177, Stockholm, Sweden
| | - Alexey Amunts
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden.
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177, Stockholm, Sweden.
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20
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Stipanuk MH. Metabolism of Sulfur-Containing Amino Acids: How the Body Copes with Excess Methionine, Cysteine, and Sulfide. J Nutr 2020; 150:2494S-2505S. [PMID: 33000151 DOI: 10.1093/jn/nxaa094] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 02/28/2020] [Accepted: 03/16/2020] [Indexed: 02/06/2023] Open
Abstract
Metabolism of excess methionine (Met) to homocysteine (Hcy) by transmethylation is facilitated by the expression of methionine adenosyltransferase (MAT) I/III and glycine N-methyltransferase (GNMT) in liver, and a lack of either enzyme results in hypermethioninemia despite normal concentrations of MATII and methyltransferases other than GNMT. The further metabolism of Hcy by the transsulfuration pathway is facilitated by activation of cystathionine β-synthase (CBS) by S-adenosylmethionine (SAM) as well as the relatively high KM of CBS for Hcy. Transmethylation plus transsulfuration effects catabolism of the Met molecule along with transfer of the sulfur atom of Met to serine to synthesize cysteine (Cys). Oxidation and excretion of Met sulfur depend upon Cys catabolism and sulfur oxidation pathways. Excess Cys is oxidized by cysteine dioxygenase 1 (CDO1) and further metabolized to taurine or sulfate. Some Cys is normally metabolized by desulfhydration pathways, and the hydrogen sulfide (H2S) produced is further oxidized to sulfate. If Cys or Hcy concentrations are elevated, Cys or Hcy desulfhydration can result in excess H2S and thiosulfate production. Excess Cys or Met may also promote their limited metabolism by transamination pathways.
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Affiliation(s)
- Martha H Stipanuk
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
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21
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Hipólito A, Nunes SC, Vicente JB, Serpa J. Cysteine Aminotransferase (CAT): A Pivotal Sponsor in Metabolic Remodeling and an Ally of 3-Mercaptopyruvate Sulfurtransferase (MST) in Cancer. Molecules 2020; 25:molecules25173984. [PMID: 32882966 PMCID: PMC7504796 DOI: 10.3390/molecules25173984] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/26/2020] [Accepted: 08/29/2020] [Indexed: 12/16/2022] Open
Abstract
Metabolic remodeling is a critical skill of malignant cells, allowing their survival and spread. The metabolic dynamics and adaptation capacity of cancer cells allow them to escape from damaging stimuli, including breakage or cross-links in DNA strands and increased reactive oxygen species (ROS) levels, promoting resistance to currently available therapies, such as alkylating or oxidative agents. Therefore, it is essential to understand how metabolic pathways and the corresponding enzymatic systems can impact on tumor behavior. Cysteine aminotransferase (CAT) per se, as well as a component of the CAT: 3-mercaptopyruvate sulfurtransferase (MST) axis, is pivotal for this metabolic rewiring, constituting a central mechanism in amino acid metabolism and fulfilling the metabolic needs of cancer cells, thereby supplying other different pathways. In this review, we explore the current state-of-art on CAT function and its role on cancer cell metabolic rewiring as MST partner, and its relevance in cancer cells' fitness.
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Affiliation(s)
- Ana Hipólito
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School|Faculty of Medical Sciences, University NOVA of Lisbon, Campus dos Mártires da Pátria, 130, 1169-056 Lisbon, Portugal; (A.H.); (S.C.N.)
- Institute of Oncology Francisco Gentil (IPOLFG), Rua Prof Lima Basto, 1099-023 Lisbon, Portugal
| | - Sofia C. Nunes
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School|Faculty of Medical Sciences, University NOVA of Lisbon, Campus dos Mártires da Pátria, 130, 1169-056 Lisbon, Portugal; (A.H.); (S.C.N.)
- Institute of Oncology Francisco Gentil (IPOLFG), Rua Prof Lima Basto, 1099-023 Lisbon, Portugal
| | - João B. Vicente
- Institute of Technology, Chemistry and Biology António Xavier (ITQB NOVA), Avenida da República (EAN), 2780-157 Oeiras, Portugal
- Correspondence: (J.B.V.); (J.S.)
| | - Jacinta Serpa
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School|Faculty of Medical Sciences, University NOVA of Lisbon, Campus dos Mártires da Pátria, 130, 1169-056 Lisbon, Portugal; (A.H.); (S.C.N.)
- Institute of Oncology Francisco Gentil (IPOLFG), Rua Prof Lima Basto, 1099-023 Lisbon, Portugal
- Correspondence: (J.B.V.); (J.S.)
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22
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Landry AP, Moon S, Bonanata J, Cho US, Coitiño EL, Banerjee R. Dismantling and Rebuilding the Trisulfide Cofactor Demonstrates Its Essential Role in Human Sulfide Quinone Oxidoreductase. J Am Chem Soc 2020; 142:14295-14306. [PMID: 32787249 DOI: 10.1021/jacs.0c06066] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Sulfide quinone oxidoreductase (SQOR) catalyzes the first step in sulfide clearance, coupling H2S oxidation to coenzyme Q reduction. Recent structures of human SQOR revealed a sulfur atom bridging the SQOR active site cysteines in a trisulfide configuration. Here, we assessed the importance of this cofactor using kinetic, crystallographic, and computational modeling approaches. Cyanolysis of SQOR proceeds via formation of an intense charge transfer complex that subsequently decays to eliminate thiocyanate. We captured a disulfanyl-methanimido thioate intermediate in the SQOR crystal structure, revealing how cyanolysis leads to reversible loss of SQOR activity that is restored in the presence of sulfide. Computational modeling and MD simulations revealed an ∼105-fold rate enhancement for nucleophilic addition of sulfide into the trisulfide versus a disulfide cofactor. The cysteine trisulfide in SQOR is thus critical for activity and provides a significant catalytic advantage over a cysteine disulfide.
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Affiliation(s)
- Aaron P Landry
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Sojin Moon
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Jenner Bonanata
- Laboratorio de Química Teórica y Computacional (LQTC), Instituto de Química Biológica, Facultad de Ciencias and Centro de Investigaciones Biomédicas (CeInBio), Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay
| | - Uhn Soo Cho
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - E Laura Coitiño
- Laboratorio de Química Teórica y Computacional (LQTC), Instituto de Química Biológica, Facultad de Ciencias and Centro de Investigaciones Biomédicas (CeInBio), Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
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Persulfides, at the crossroads between hydrogen sulfide and thiols. Essays Biochem 2020; 64:155-168. [DOI: 10.1042/ebc20190049] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 01/13/2020] [Accepted: 01/15/2020] [Indexed: 12/14/2022]
Abstract
AbstractPersulfides (RSSH/RSS−) can be formed in protein and non-protein thiols (RSH) through several different pathways, some of which are dependent on hydrogen sulfide (H2S/HS−). In addition to their roles in biosynthetic processes, persulfides are possible transducers of physiological effects of H2S through the modification of critical cysteines. Persulfides have a very rich biological chemistry that is currently under investigation. They are more nucleophilic and acidic than thiols and, unlike thiols, they can also be electrophilic. They are especially good one-electron reductants. Methods to detect their formation are under continuous development. In this minireview we describe the pathways of formation of persulfides, their biochemical properties and the techniques available for their detection, and we discuss the possible implications of their formation in biological systems.
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Lencina AM, Gennis RB, Schurig-Briccio LA. The oligomeric state of the Caldivirga maquilingensis type III sulfide:Quinone Oxidoreductase is required for membrane binding. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148132. [PMID: 31816290 DOI: 10.1016/j.bbabio.2019.148132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 09/11/2019] [Accepted: 12/04/2019] [Indexed: 12/24/2022]
Abstract
Sulfide:quinone oxidoreductase (SQR) is a monotopic membrane flavoprotein present in all domains of life, with multiple roles including sulfide detoxification, homeostasis and energy generation by providing electrons to respiratory or photosynthetic electron transport chains. A type III SQR from the hyperthermophilic archeon Caldivirga maquilingensis has been previously characterized, and its C-terminal amphipathic helices were demonstrated to be responsible for membrane binding. Here, the oligomeric state of this protein was experimentally evaluated by size exclusion chromatography, native gels and crosslinking, and found to be a monomer-dimer-trimer equilibrium. Remarkably, mutant and truncated variants unable to bind to the membrane are able to maintain their oligomeric association. Thus, unlike other related monotopic membrane proteins, the region involved in membrane binding does not influence oligomerization. Furthermore, by studying heterodimers between the WT and mutants, it was concluded that membrane binding requires an oligomer with at least two copies of the protein with intact C-terminal amphipathic helices. A structural homology model of the C. maquilingensis SQR was used to define the flavin- and quinone-binding sites. CmGly12, CmGly16, CmAla77 and CmPro44 were determined to be important for flavin binding. Unexpectedly, CmGly299 is only important for quinone reduction despite its proximity to bound FAD. CmPhe337 and CmPhe362 are also important for quinone binding apparently by direct interaction with the quinone ring, whereas CmLys359, postulated to hydrogen bond to the quinone, seems to have a more structural role. The results presented differentiate the Type III CmSQR from some of its counterparts classified as Type I, II and V.
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Affiliation(s)
- Andrea M Lencina
- Department of Biochemistry, University of Illinois, 600 S. Mathews Street, Urbana, IL 61801, USA
| | - Robert B Gennis
- Department of Biochemistry, University of Illinois, 600 S. Mathews Street, Urbana, IL 61801, USA
| | - Lici A Schurig-Briccio
- Department of Biochemistry, University of Illinois, 600 S. Mathews Street, Urbana, IL 61801, USA.
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25
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Giuffrè A, Tomé CS, Fernandes DGF, Zuhra K, Vicente JB. Hydrogen Sulfide Metabolism and Signaling in the Tumor Microenvironment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1219:335-353. [PMID: 32130707 DOI: 10.1007/978-3-030-34025-4_17] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Hydrogen sulfide (H2S), while historically perceived merely as a toxicant, has progressively emerged as a key regulator of numerous processes in mammalian physiology, exerting its signaling function essentially through interaction with and/or modification of proteins, targeting mainly cysteine residues and metal centers. As a gaseous signaling molecule that freely diffuses across aqueous and hydrophobic biological milieu, it has been designated the third 'gasotransmitter' in mammalian physiology. H2S is synthesized and detoxified by specialized endogenous enzymes that operate under a tight regulation, ensuring homeostatic levels of this otherwise toxic molecule. Indeed, imbalances in H2S levels associated with dysfunctional H2S metabolism have been growingly correlated with various human pathologies, from cardiovascular and neurodegenerative diseases to cancer. Several cancer cell lines and specimens have been shown to naturally overexpress one or more of the H2S-synthesizing enzymes. The resulting increased H2S levels have been proposed to promote cancer development through the regulation of various cancer-related processes, which led to the interest in pharmacological targeting of H2S metabolism. Herein are summarized some of the key observations that place H2S metabolism and signaling pathways at the forefront of the cellular mechanisms that support the establishment and development of a tumor within its complex and challenging microenvironment. Special emphasis is given to the mechanisms whereby H2S helps shaping cancer cell bioenergetic metabolism and affords resistance and adaptive mechanisms to hypoxia.
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Affiliation(s)
| | - Catarina S Tomé
- Instituto de Tecnologia Química e Biológica António Xavier, NOVA University of Lisbon, Oeiras, Portugal
| | - Dalila G F Fernandes
- Instituto de Tecnologia Química e Biológica António Xavier, NOVA University of Lisbon, Oeiras, Portugal
| | - Karim Zuhra
- CNR Institute of Molecular Biology and Pathology, Rome, Italy
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - João B Vicente
- Instituto de Tecnologia Química e Biológica António Xavier, NOVA University of Lisbon, Oeiras, Portugal.
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Landry AP, Moon S, Kim H, Yadav PK, Guha A, Cho US, Banerjee R. A Catalytic Trisulfide in Human Sulfide Quinone Oxidoreductase Catalyzes Coenzyme A Persulfide Synthesis and Inhibits Butyrate Oxidation. Cell Chem Biol 2019; 26:1515-1525.e4. [PMID: 31591036 DOI: 10.1016/j.chembiol.2019.09.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/29/2019] [Accepted: 09/17/2019] [Indexed: 01/09/2023]
Abstract
Mitochondrial sulfide quinone oxidoreductase (SQR) catalyzes the oxidation of H2S to glutathione persulfide with concomitant reduction of CoQ10. We report herein that the promiscuous activity of human SQR supported the conversion of CoA to CoA-SSH (CoA-persulfide), a potent inhibitor of butyryl-CoA dehydrogenase, and revealed a molecular link between sulfide and butyrate metabolism, which are known to interact. Three different CoQ1-bound crystal structures furnished insights into how diverse substrates access human SQR, and provided snapshots of the reaction coordinate. Unexpectedly, the active site cysteines in SQR are configured in a bridging trisulfide at the start and end of the catalytic cycle, and the presence of sulfane sulfur was confirmed biochemically. Importantly, our study leads to a mechanistic proposal for human SQR in which sulfide addition to the trisulfide cofactor eliminates 201Cys-SSH, forming an intense charge-transfer complex with flavin adenine dinucleotide, and 379Cys-SSH, which transfers sulfur to an external acceptor.
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Affiliation(s)
- Aaron P Landry
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Sojin Moon
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Hanseong Kim
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Pramod K Yadav
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Arkajit Guha
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Uhn-Soo Cho
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
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27
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Bonanata J, Coitiño EL. Understanding the mechanism of H 2S oxidation by flavin-dependent sulfide oxidases: a DFT/IEF-PCM study. J Mol Model 2019; 25:308. [PMID: 31502063 DOI: 10.1007/s00894-019-4197-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 08/28/2019] [Indexed: 12/18/2022]
Abstract
In the last years, H2S has been recognized as a signaling molecule in mammals, which can synthesize and catabolize (by oxidation) such species. The latter process is accelerated by a sulfide:quinone oxidoreductase (SQR, E.C. 1.8.5.4), a flavin-dependent sulfide oxidase (FDSO). FDSOs catalyze electron transfer from H2S to an acceptor in catalytic cycles involving two phases: (I) reduction of FAD by H2S (SH-) and (II) electron transfer from FADH- to the electron acceptor. The first step of FAD reduction consists on the reaction of SH- with a catalytic disulfide at the active site of the enzyme, to yield a thiolate and a persulfide in the protein. This step is ca. 106 times faster than the analogous reaction with low-molecular-weight disulfides (LMWDs) and the causes of such extraordinary acceleration remain unknown. Using the IEF-PCM(ε ≈ 10)/M06-2X-D3/6-31+G(d,p) level of theory, we have modeled the reaction of SH- with a disulfide as located in a representative model of the active site extracted from a prokaryotic SQR, assessing the effects of partial covalent interactions (PCIs) between the leaving sulfur atom and flavin ring on the activation Gibbs free-energy barrier at 298 K (∆‡G298K). To also evaluate the importance of entropic penalties on the first step, we have modeled at the same level of theory the reaction of (bis)hydroxyethyl disulfide in aqueous solution, a LMWD for which experimental data is available. Our results show that PCIs between the leaving sulfur atom and the flavin group only have a minor effect (∆‡G298K reduced by 1.6 kcal mol-1) while compensating entropic penalties could have a much larger effect (up to 8.3 kcal mol-1). Finally, we also present here a first model of some of further steps in the phase I of the catalytic cycle as in mammalian FDSOs, providing some light about their detailed mechanism. Graphical abstract .
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Affiliation(s)
- Jenner Bonanata
- Laboratorio de Química Teórica y Computacional, Instituto de Química Biológica, Facultad de Ciencias and Centro de Investigaciones Biomédicas (CEINBIO), Universidad de la República, Iguá 4225, 11400, Montevideo, Uruguay.
| | - E Laura Coitiño
- Laboratorio de Química Teórica y Computacional, Instituto de Química Biológica, Facultad de Ciencias and Centro de Investigaciones Biomédicas (CEINBIO), Universidad de la República, Iguá 4225, 11400, Montevideo, Uruguay.
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