1
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Reynolds MF. New insights into the signal transduction mechanism of O 2-sensing FixL and other biological heme-based sensor proteins. J Inorg Biochem 2024; 259:112642. [PMID: 38908215 DOI: 10.1016/j.jinorgbio.2024.112642] [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: 02/05/2024] [Revised: 05/24/2024] [Accepted: 06/13/2024] [Indexed: 06/24/2024]
Abstract
Recent structural and biophysical studies of O2-sensing FixL, NO-sensing soluble guanylate cyclase, and other biological heme-based sensing proteins have begun to reveal the details of their molecular mechanisms and shed light on how nature regulates important biological processes such as nitrogen fixation, blood pressure, neurotransmission, photosynthesis and circadian rhythm. The O2-sensing FixL protein from S. meliloti, the eukaryotic NO-sensing protein sGC, and the CO-sensing CooA protein from R. rubrum transmit their biological signals through gas-binding to the heme domain of these proteins, which inhibits or activates the regulatory, enzymatic domain. These proteins appear to propagate their signal by specific structural changes in the heme sensor domain initiated by the appropriate gas binding to the heme, which is then propagated through a coiled-coil linker or other domain to the regulatory, enzymatic domain that sends out the biological signal. The current understanding of the signal transduction mechanisms of O2-sensing FixL, NO-sensing sGC, CO-sensing CooA and other biological heme-based gas sensing proteins and their mechanistic themes are discussed, with recommendations for future work to further understand this rapidly growing area of biological heme-based gas sensors.
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Affiliation(s)
- Mark F Reynolds
- Department of Chemistry and Biochemistry, Saint Joseph's University, 5600 City Avenue, Philadelphia, PA 19131, United States of America.
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2
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Bansal S, Liu D, Mao Q, Bauer N, Wang B. Carbon Monoxide as a Potential Therapeutic Agent: A Molecular Analysis of Its Safety Profiles. J Med Chem 2024; 67:9789-9815. [PMID: 38864348 PMCID: PMC11215727 DOI: 10.1021/acs.jmedchem.4c00823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 05/20/2024] [Accepted: 05/29/2024] [Indexed: 06/13/2024]
Abstract
Carbon monoxide (CO) is endogenously produced in mammals, with blood concentrations in the high micromolar range in the hemoglobin-bound form. Further, CO has shown therapeutic effects in various animal models. Despite its reputation as a poisonous gas at high concentrations, we show that CO should have a wide enough safety margin for therapeutic applications. The analysis considers a large number of factors including levels of endogenous CO, its safety margin in comparison to commonly encountered biomolecules or drugs, anticipated enhanced safety profiles when delivered via a noninhalation mode, and the large amount of safety data from human clinical trials. It should be emphasized that having a wide enough safety margin for therapeutic use does not mean that it is benign or safe to the general public, even at low doses. We defer the latter to public health experts. Importantly, this Perspective is written for drug discovery professionals and not the general public.
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Affiliation(s)
| | | | | | - Nicola Bauer
- Department of Chemistry and
the Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia 30303, United States
| | - Binghe Wang
- Department of Chemistry and
the Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia 30303, United States
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3
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Marson NA, Gallio AE, Mandal SK, Laskowski RA, Raven EL. In silico prediction of heme binding in proteins. J Biol Chem 2024; 300:107250. [PMID: 38569935 PMCID: PMC11101860 DOI: 10.1016/j.jbc.2024.107250] [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: 01/19/2024] [Revised: 03/11/2024] [Accepted: 03/26/2024] [Indexed: 04/05/2024] Open
Abstract
The process of heme binding to a protein is prevalent in almost all forms of life to control many important biological properties, such as O2-binding, electron transfer, gas sensing or to build catalytic power. In these cases, heme typically binds tightly (irreversibly) to a protein in a discrete heme binding pocket, with one or two heme ligands provided most commonly to the heme iron by His, Cys or Tyr residues. Heme binding can also be used as a regulatory mechanism, for example in transcriptional regulation or ion channel control. When used as a regulator, heme binds more weakly, with different heme ligations and without the need for a discrete heme pocket. This makes the characterization of heme regulatory proteins difficult, and new approaches are needed to predict and understand the heme-protein interactions. We apply a modified version of the ProFunc bioinformatics tool to identify heme-binding sites in a test set of heme-dependent regulatory proteins taken from the Protein Data Bank and AlphaFold models. The potential heme binding sites identified can be easily visualized in PyMol and, if necessary, optimized with RosettaDOCK. We demonstrate that the methodology can be used to identify heme-binding sites in proteins, including in cases where there is no crystal structure available, but the methodology is more accurate when the quality of the structural information is high. The ProFunc tool, with the modification used in this work, is publicly available at https://www.ebi.ac.uk/thornton-srv/databases/profunc and can be readily adopted for the examination of new heme binding targets.
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Affiliation(s)
- Noa A Marson
- School of Chemistry, University of Bristol, Bristol, UK
| | | | | | - Roman A Laskowski
- European Bioinformatics Institute (EMBL-EBI), European Molecular Biology Laboratory, Wellcome Trust Genome Campus, Cambridge, UK
| | - Emma L Raven
- School of Chemistry, University of Bristol, Bristol, UK.
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4
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Freeman SL, Oliveira ASF, Gallio AE, Rosa A, Simitakou MK, Arthur CJ, Mulholland AJ, Cherepanov P, Raven EL. Heme binding to the SARS-CoV-2 spike glycoprotein. J Biol Chem 2023; 299:105014. [PMID: 37414149 PMCID: PMC10416065 DOI: 10.1016/j.jbc.2023.105014] [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] [Received: 04/11/2023] [Revised: 06/12/2023] [Accepted: 07/01/2023] [Indexed: 07/08/2023] Open
Abstract
The target for humoral immunity, SARS-CoV-2 spike glycoprotein, has become the focus of vaccine research and development. Previous work demonstrated that the N-terminal domain (NTD) of SARS-CoV-2 spike binds biliverdin-a product of heme catabolism-causing a strong allosteric effect on the activity of a subset of neutralizing antibodies. Herein, we show that the spike glycoprotein is also able to bind heme (KD = 0.5 ± 0.2 μM). Molecular modeling indicated that the heme group fits well within the same pocket on the SARS-CoV-2 spike NTD. Lined by aromatic and hydrophobic residues (W104, V126, I129, F192, F194, I203, and L226), the pocket provides a suitable environment to stabilize the hydrophobic heme. Mutagenesis of N121 has a substantive effect on heme binding (KD = 3000 ± 220 μM), confirming the pocket as a major heme binding location of the viral glycoprotein. Coupled oxidation experiments in the presence of ascorbate indicated that the SARS-CoV-2 glycoprotein can catalyze the slow conversion of heme to biliverdin. The heme trapping and oxidation activities of the spike may allow the virus to reduce levels of free heme during infection to facilitate evasion of the adaptive and innate immunity.
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Affiliation(s)
- Samuel L Freeman
- School of Chemistry, Cantock's Close, University of Bristol, Bristol, United Kingdom
| | - A Sofia F Oliveira
- School of Chemistry, Cantock's Close, University of Bristol, Bristol, United Kingdom
| | - Andrea E Gallio
- School of Chemistry, Cantock's Close, University of Bristol, Bristol, United Kingdom
| | - Annachiara Rosa
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Maria K Simitakou
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Christopher J Arthur
- School of Chemistry, Cantock's Close, University of Bristol, Bristol, United Kingdom
| | - Adrian J Mulholland
- School of Chemistry, Cantock's Close, University of Bristol, Bristol, United Kingdom
| | - Peter Cherepanov
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, United Kingdom; Department of Infectious Disease, St-Mary's Campus, Imperial College London, United Kingdom.
| | - Emma L Raven
- School of Chemistry, Cantock's Close, University of Bristol, Bristol, United Kingdom.
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5
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Dai Y, Fleischhacker AS, Liu L, Fayad S, Gunawan AL, Stuehr DJ, Ragsdale SW. Heme delivery to heme oxygenase-2 involves glyceraldehyde-3-phosphate dehydrogenase. Biol Chem 2022; 403:1043-1053. [PMID: 36302634 PMCID: PMC9661526 DOI: 10.1515/hsz-2022-0230] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 10/10/2022] [Indexed: 11/15/2022]
Abstract
Abstract
Heme regulatory motifs (HRMs) are found in a variety of proteins with diverse biological functions. In heme oxygenase-2 (HO2), heme binds to the HRMs and is readily transferred to the catalytic site in the core of the protein. To further define this heme transfer mechanism, we evaluated the ability of GAPDH, a known heme chaperone, to transfer heme to the HRMs and/or the catalytic core of HO2. Our results indicate GAPDH and HO2 form a complex in vitro. We have followed heme insertion at both sites by fluorescence quenching in HEK293 cells with HO2 reporter constructs. Upon mutation of residues essential for heme binding at each site in our reporter construct, we found that HO2 binds heme at the core and the HRMs in live cells and that heme delivery to HO2 is dependent on the presence of GAPDH that is competent for heme binding. In sum, GAPDH is involved in heme delivery to HO2 but, surprisingly, not to a specific site on HO2. Our results thus emphasize the importance of heme binding to both the core and the HRMs and the interplay of HO2 with the heme pool via GAPDH to maintain cellular heme homeostasis.
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Affiliation(s)
- Yue Dai
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, NC-22, 9500 Euclid Avenue, Cleveland, OH44195, USA
| | - Angela S. Fleischhacker
- Department of Biological Chemistry, University of Michigan, 1150 W. Medical Center Dr., 5301 MSRB III, Ann Arbor, MI48109, USA
| | - Liu Liu
- Department of Biological Chemistry, University of Michigan, 1150 W. Medical Center Dr., 5301 MSRB III, Ann Arbor, MI48109, USA
| | - Sara Fayad
- Department of Biological Chemistry, University of Michigan, 1150 W. Medical Center Dr., 5301 MSRB III, Ann Arbor, MI48109, USA
| | - Amanda L. Gunawan
- Department of Biological Chemistry, University of Michigan, 1150 W. Medical Center Dr., 5301 MSRB III, Ann Arbor, MI48109, USA
| | - Dennis J. Stuehr
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, NC-22, 9500 Euclid Avenue, Cleveland, OH44195, USA
| | - Stephen W. Ragsdale
- Department of Biological Chemistry, University of Michigan, 1150 W. Medical Center Dr., 5301 MSRB III, Ann Arbor, MI48109, USA
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6
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Jenner LP, Crack JC, Kurth JM, Soldánová Z, Brandt L, Sokol KP, Reisner E, Bradley JM, Dahl C, Cheesman MR, Butt JN. Reaction of Thiosulfate Dehydrogenase with a Substrate Mimic Induces Dissociation of the Cysteine Heme Ligand Giving Insights into the Mechanism of Oxidative Catalysis. J Am Chem Soc 2022; 144:18296-18304. [PMID: 36173876 PMCID: PMC9562282 DOI: 10.1021/jacs.2c06062] [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] [Indexed: 11/29/2022]
Abstract
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Thiosulfate dehydrogenases are bacterial cytochromes
that contribute
to the oxidation of inorganic sulfur. The active sites of these enzymes
contain low-spin c-type heme with Cys–/His axial ligation. However, the reduction potentials of these hemes
are several hundred mV more negative than that of the thiosulfate/tetrathionate
couple (Em, +198 mV), making it difficult
to rationalize the thiosulfate oxidizing capability. Here, we describe
the reaction of Campylobacter jejuni thiosulfate dehydrogenase (TsdA) with sulfite, an analogue of thiosulfate.
The reaction leads to stoichiometric conversion of the active site
Cys to cysteinyl sulfonate (Cα-CH2-S-SO3–) such that the protein exists in a form
closely resembling a proposed intermediate in the pathway for thiosulfate
oxidation that carries a cysteinyl thiosulfate (Cα-CH2-S-SSO3–). The active
site heme in the stable sulfonated protein displays an Em approximately 200 mV more positive than the Cys–/His-ligated state. This can explain the thiosulfate
oxidizing activity of the enzyme and allows us to propose a catalytic
mechanism for thiosulfate oxidation. Substrate-driven release of the
Cys heme ligand allows that side chain to provide the site of substrate
binding and redox transformation; the neighboring heme then simply
provides a site for electron relay to an appropriate partner. This
chemistry is distinct from that displayed by the Cys-ligated hemes
found in gas-sensing hemoproteins and in enzymes such as the cytochromes
P450. Thus, a further class of thiolate-ligated hemes is proposed,
as exemplified by the TsdA centers that have evolved to catalyze the
controlled redox transformations of inorganic oxo anions of sulfur.
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Affiliation(s)
- Leon P Jenner
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, NorwichNR4 7TJ, United Kingdom
| | - Jason C Crack
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, NorwichNR4 7TJ, United Kingdom
| | - Julia M Kurth
- Institut für Mikrobiologie & Biotechnologie, Friedrich Wilhelms Universität Bonn, D-53115Bonn, Germany
| | - Zuzana Soldánová
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, NorwichNR4 7TJ, United Kingdom
| | - Linda Brandt
- Institut für Mikrobiologie & Biotechnologie, Friedrich Wilhelms Universität Bonn, D-53115Bonn, Germany
| | - Katarzyna P Sokol
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, CambridgeCB2 1EW, United Kingdom
| | - Erwin Reisner
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, CambridgeCB2 1EW, United Kingdom
| | - Justin M Bradley
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, NorwichNR4 7TJ, United Kingdom
| | - Christiane Dahl
- Institut für Mikrobiologie & Biotechnologie, Friedrich Wilhelms Universität Bonn, D-53115Bonn, Germany
| | - Myles R Cheesman
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, NorwichNR4 7TJ, United Kingdom
| | - Julea N Butt
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, NorwichNR4 7TJ, United Kingdom
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7
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Vávra J, Sergunin A, Jeřábek P, Shimizu T, Martínková M. Signal transduction mechanisms in heme-based globin-coupled oxygen sensors with a focus on a histidine kinase ( AfGcHK) and a diguanylate cyclase (YddV or EcDosC). Biol Chem 2022; 403:1031-1042. [PMID: 36165459 DOI: 10.1515/hsz-2022-0185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 09/08/2022] [Indexed: 01/19/2023]
Abstract
Heme is a vital cofactor of proteins with roles in oxygen transport (e.g. hemoglobin), storage (e.g. myoglobin), and activation (e.g. P450) as well as electron transfer (e.g. cytochromes) and many other functions. However, its structural and functional role in oxygen sensing proteins differs markedly from that in most other enzymes, where it serves as a catalytic or functional center. This minireview discusses the mechanism of signal transduction in two heme-based oxygen sensors: the histidine kinase AfGcHK and the diguanylate cyclase YddV (EcDosC), both of which feature a heme-binding domain containing a globin fold resembling that of hemoglobin and myoglobin.
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Affiliation(s)
- Jakub Vávra
- Department of Biochemistry, Faculty of Science, Charles University, Prague 2, 128 43 Czech Republic
| | - Artur Sergunin
- Department of Biochemistry, Faculty of Science, Charles University, Prague 2, 128 43 Czech Republic
| | - Petr Jeřábek
- Department of Biochemistry, Faculty of Science, Charles University, Prague 2, 128 43 Czech Republic
| | - Toru Shimizu
- Department of Biochemistry, Faculty of Science, Charles University, Prague 2, 128 43 Czech Republic
| | - Markéta Martínková
- Department of Biochemistry, Faculty of Science, Charles University, Prague 2, 128 43 Czech Republic
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8
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Zatsikha YV, Schrage BR, Blesener TS, Harrison LA, Ziegler CJ, Nemykin VN. Meso
‐Carbon Atom Nucleophilic Attack Susceptibility in the Sterically Strained Antiaromatic Bis‐BODIPY Macrocycle and Extended Electron‐Deficient BODIPY Precursor**. Chemistry 2022; 28:e202201261. [DOI: 10.1002/chem.202201261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Indexed: 11/07/2022]
Affiliation(s)
- Yuriy V. Zatsikha
- Department of Chemistry University of Manitoba Winnipeg MB R3T 2N2 Canada
- Enamine Ltd Chervonotkatska Street 78 Kyiv 02094 Ukraine
| | - Briana R. Schrage
- Department of Chemistry University of Tennessee – Knoxville Knoxville TN 37996 USA
| | - Tanner S. Blesener
- Department of Chemistry University of Tennessee – Knoxville Knoxville TN 37996 USA
| | - Laurel A. Harrison
- Department of Chemistry University of Tennessee – Knoxville Knoxville TN 37996 USA
| | | | - Victor N. Nemykin
- Department of Chemistry University of Tennessee – Knoxville Knoxville TN 37996 USA
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9
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Stuehr DJ, Dai Y, Biswas P, Sweeny EA, Ghosh A. New roles for GAPDH, Hsp90, and NO in regulating heme allocation and hemeprotein function in mammals. Biol Chem 2022; 403:1005-1015. [PMID: 36152339 PMCID: PMC10184026 DOI: 10.1515/hsz-2022-0197] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 08/17/2022] [Indexed: 12/23/2022]
Abstract
The intracellular trafficking of mitochondrial heme presents a fundamental challenge to animal cells. This article provides some background on heme allocation, discusses some of the concepts, and then reviews research done over the last decade, much in the author's laboratory, that is uncovering unexpected and important roles for glyceraldehyde 3-phosphate dehydrogenase (GAPDH), heat shock protein 90 (hsp90), and nitric oxide (NO) in enabling and regulating the allocation of mitochondrial heme to hemeproteins that mature and function outside of the mitochondria. A model for how hemeprotein functions can be regulated in cells through the coordinate participation of GAPDH, hsp90, and NO in allocating cellular heme is presented.
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Affiliation(s)
- Dennis J Stuehr
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Yue Dai
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Pranjal Biswas
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Elizabeth A Sweeny
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Arnab Ghosh
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA
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10
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Heme Oxygenase-1: An Anti-Inflammatory Effector in Cardiovascular, Lung, and Related Metabolic Disorders. Antioxidants (Basel) 2022; 11:antiox11030555. [PMID: 35326205 PMCID: PMC8944973 DOI: 10.3390/antiox11030555] [Citation(s) in RCA: 78] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 02/24/2022] [Accepted: 03/10/2022] [Indexed: 12/12/2022] Open
Abstract
The heme oxygenase (HO) enzyme system catabolizes heme to carbon monoxide (CO), ferrous iron, and biliverdin-IXα (BV), which is reduced to bilirubin-IXα (BR) by biliverdin reductase (BVR). HO activity is represented by two distinct isozymes, the inducible form, HO-1, and a constitutive form, HO-2, encoded by distinct genes (HMOX1, HMOX2, respectively). HO-1 responds to transcriptional activation in response to a wide variety of chemical and physical stimuli, including its natural substrate heme, oxidants, and phytochemical antioxidants. The expression of HO-1 is regulated by NF-E2-related factor-2 and counter-regulated by Bach-1, in a heme-sensitive manner. Additionally, HMOX1 promoter polymorphisms have been associated with human disease. The induction of HO-1 can confer protection in inflammatory conditions through removal of heme, a pro-oxidant and potential catalyst of lipid peroxidation, whereas iron released from HO activity may trigger ferritin synthesis or ferroptosis. The production of heme-derived reaction products (i.e., BV, BR) may contribute to HO-dependent cytoprotection via antioxidant and immunomodulatory effects. Additionally, BVR and BR have newly recognized roles in lipid regulation. CO may alter mitochondrial function leading to modulation of downstream signaling pathways that culminate in anti-apoptotic, anti-inflammatory, anti-proliferative and immunomodulatory effects. This review will present evidence for beneficial effects of HO-1 and its reaction products in human diseases, including cardiovascular disease (CVD), metabolic conditions, including diabetes and obesity, as well as acute and chronic diseases of the liver, kidney, or lung. Strategies targeting the HO-1 pathway, including genetic or chemical modulation of HO-1 expression, or application of BR, CO gas, or CO donor compounds show therapeutic potential in inflammatory conditions, including organ ischemia/reperfusion injury. Evidence from human studies indicate that HO-1 expression may represent a biomarker of oxidative stress in various clinical conditions, while increases in serum BR levels have been correlated inversely to risk of CVD and metabolic disease. Ongoing human clinical trials investigate the potential of CO as a therapeutic in human disease.
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11
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Ahmad F, Luo Y, Yin H, Zhang Y, Huang Y. Identification and analysis of iron transporters from the fission yeast Schizosaccharomyces pombe. Arch Microbiol 2022; 204:152. [PMID: 35079912 DOI: 10.1007/s00203-021-02683-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/22/2021] [Accepted: 10/25/2021] [Indexed: 12/14/2022]
Abstract
Iron is an essential trace metal ion required for all living organisms, and is taken up by iron transporters. Here, we identified and characterized three-candidate high-affinity (Fio1, Frp1 and Frp2) and two-candidate low-affinity iron transporters (Fet4 and Pdt1) from the fission yeast Schizosaccharomyces pombe. Protein sequence analyses revealed that Fio1 is a multicopper oxidase that contains three cupredoxin domains with eleven candidate iron-binding ligands, whereas Frp1 harbors a ferric reductase domain with three-candidate heme-binding ligands. Protein sequence analyses also revealed that Fet4 and Pdt1 are integral membrane proteins with 10 and 11 transmembrane regions, respectively. Deletion of fio1 and, to a lesser extent, frp1 impaired growth under iron-depleted conditions, whereas deletion of frp1 and, to a lesser extent, frp2 inhibited growth under iron-replete conditions. Deletion of fet4 and pdt1 did not affect the growth of cells under iron-depleted and iron-replete conditions. Deletion of fio1 or frp1 also increased the sensitivity of cells to other transition metals. The copper sensitivity of Δfio1 cells could be rescued by iron, suggesting that the addition of iron might decrease the uptake of potentially toxic copper in Δfio1 cells. The copper sensitivity of Δfio1 cells could also be rescued by deletion of frp1, suggesting that Fio1 and Frp1 may function together in iron and copper uptakes in S. pombe. Our results revealed that iron and copper uptake systems may be partially overlapped in S. pombe.
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Affiliation(s)
- Fawad Ahmad
- Jiangsu Key Laboratory for Microbes and Genomics, School of Life Sciences, Nanjing Normal University, 1 wenyuan Road, Nanjing, 210023, China
| | - Ying Luo
- Jiangsu Key Laboratory for Microbes and Genomics, School of Life Sciences, Nanjing Normal University, 1 wenyuan Road, Nanjing, 210023, China
| | - Helong Yin
- Jiangsu Key Laboratory for Microbes and Genomics, School of Life Sciences, Nanjing Normal University, 1 wenyuan Road, Nanjing, 210023, China
| | - Yun Zhang
- Jiangsu Key Laboratory for Microbes and Genomics, School of Life Sciences, Nanjing Normal University, 1 wenyuan Road, Nanjing, 210023, China
| | - Ying Huang
- Jiangsu Key Laboratory for Microbes and Genomics, School of Life Sciences, Nanjing Normal University, 1 wenyuan Road, Nanjing, 210023, China.
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