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Messias A, Capece L, De Simone G, Coletta M, Ascenzi P, Estrin DA. Mechanism of Peroxynitrite Interaction with Ferric M. tuberculosis Nitrobindin: A Computational Study. Inorg Chem 2024; 63:9907-9918. [PMID: 38754069 DOI: 10.1021/acs.inorgchem.4c00833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
Nitrobindins (Nbs) are all-β-barrel heme proteins present along the evolutionary ladder. They display a highly solvent-exposed ferric heme group with the iron atom being coordinated by the proximal His residue and a water molecule at the distal position. Ferric nitrobindins (Nb(III)) play a role in the conversion of toxic peroxynitrite (ONOO-) to harmless nitrate, with the value of the second-order rate constant being similar to those of most heme proteins. The value of the second-order rate constant of Nbs increases as the pH decreases; this suggests that Nb(III) preferentially reacts with peroxynitrous acid (ONOOH), although ONOO- is more nucleophilic. In this work, we shed light on the molecular basis of the ONOO- and ONOOH reactivity of ferric Mycobacterium tuberculosis Nb (Mt-Nb(III)) by dissecting the ligand migration toward the active site, the water molecule release, and the ligand binding process by computer simulations. Classical molecular dynamics simulations were performed by employing a steered molecular dynamics approach and the Jarzynski equality to obtain ligand migration free energy profiles for both ONOO- and ONOOH. Our results indicate that ONOO- and ONOOH migration is almost unhindered, consistent with the exposed metal center of Mt-Nb(III). To further analyze the ligand binding process, we computed potential energy profiles for the displacement of the Fe(III)-coordinated water molecule using a hybrid QM/MM scheme at the DFT level and a nudged elastic band approach. These results indicate that ONOO- exhibits a much larger barrier for ligand displacement than ONOOH, suggesting that water displacement is assisted by protonation of the leaving group by the incoming ONOOH.
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Affiliation(s)
- Andresa Messias
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Intendente Güiraldes 2160, C1428EHA Buenos Aires, Argentina
- CONICET - Universidad de Buenos Aires, Instituto de Química-Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina
| | - Luciana Capece
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Intendente Güiraldes 2160, C1428EHA Buenos Aires, Argentina
- CONICET - Universidad de Buenos Aires, Instituto de Química-Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina
| | - Giovanna De Simone
- Department of Sciences, Roma Tre University, Viale G. Marconi, 446, I-00146 Roma, Italy
| | - Massimo Coletta
- IRCCS Fondazione Bietti, Via Santo Stefano Rotondo, 6, 00184 Roma, Italy
| | - Paolo Ascenzi
- Department of Sciences, Roma Tre University, Viale G. Marconi, 446, I-00146 Roma, Italy
- Accademia Nazionale dei Lincei, Via della Lungara, 10, 00165 Roma, Italy
| | - Darío A Estrin
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Intendente Güiraldes 2160, C1428EHA Buenos Aires, Argentina
- CONICET - Universidad de Buenos Aires, Instituto de Química-Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina
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De Simone G, di Masi A, Pasquadibisceglie A, Coletta A, Sebastiani F, Smulevich G, Coletta M, Ascenzi P. Nitrobindin versus myoglobin: A comparative structural and functional study. J Inorg Biochem 2024; 250:112387. [PMID: 37914583 DOI: 10.1016/j.jinorgbio.2023.112387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 09/20/2023] [Accepted: 09/24/2023] [Indexed: 11/03/2023]
Abstract
Most hemoproteins display an all-α-helical fold, showing the classical three on three (3/3) globin structural arrangement characterized by seven or eight α-helical segments that form a sandwich around the heme. Over the last decade, a completely distinct class of heme-proteins called nitrobindins (Nbs), which display an all-β-barrel fold, has been identified and characterized from both structural and functional perspectives. Nbs are ten-stranded anti-parallel all-β-barrel heme-proteins found across the evolutionary ladder, from bacteria to Homo sapiens. Myoglobin (Mb), commonly regarded as the prototype of monomeric all-α-helical globins, is involved along with the oligomeric hemoglobin (Hb) in diatomic gas transport, storage, and sensing, as well as in the detoxification of reactive nitrogen and oxygen species. On the other hand, the function(s) of Nbs is still obscure, even though it has been postulated that they might participate to O2/NO signaling and metabolism. This function might be of the utmost importance in poorly oxygenated tissues, such as the eye's retina, where a delicate balance between oxygenation and blood flow (regulated by NO) is crucial. Dysfunction in this balance is associated with several pathological conditions, such as glaucoma and diabetic retinopathy. Here a detailed comparison of the structural, spectroscopic, and functional properties of Mb and Nbs is reported to shed light on the similarities and differences between all-α-helical and all-β-barrel heme-proteins.
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Affiliation(s)
| | | | | | | | - Federico Sebastiani
- Dipartimento di Chimica "Ugo Schiff" (DICUS), Università di Firenze, 50019 Sesto Fiorentino, FI, Italy
| | - Giulietta Smulevich
- Dipartimento di Chimica "Ugo Schiff" (DICUS), Università di Firenze, 50019 Sesto Fiorentino, FI, Italy
| | | | - Paolo Ascenzi
- Laboratorio Interdipartimentale di Microscopia Elettronica, Università Roma Tre, 00146 Roma, Italy.
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Messias A, Pasquadibisceglie A, Alonso de Armiño D, De Simone G, Polticelli F, Coletta M, Ascenzi P, Estrin DA. Nitric oxide binding to ferrous nitrobindins: A computer simulation investigation. J Inorg Biochem 2023; 248:112336. [PMID: 37572543 DOI: 10.1016/j.jinorgbio.2023.112336] [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: 05/20/2023] [Revised: 06/28/2023] [Accepted: 07/19/2023] [Indexed: 08/14/2023]
Abstract
Nitrobindins (Nbs) represent an evolutionary conserved all-β-barrel heme-proteins displaying a highly solvent-exposed heme-Fe(III) atom, coordinated by a proximal His residue. Interestingly, even if the distal side is exposed to the solvent, the value of the second order rate constants for ligand binding to the ferrous derivative is almost one order of magnitude lower than those reported for myoglobins (Mbs). Noteworthy, nitric oxide binding to the sixth coordination position of the heme-Fe(II)-atom causes the cleavage or the severe weakening of the proximal His-Fe(II) bond. Here, we provide a computer simulation investigation to shed light on the molecular basis of ligand binding kinetics, by dissecting the ligand binding process into the ligand migration and the bond formation steps. Classical molecular dynamics simulations were performed employing a steered molecular dynamics approach and the Jarzinski equality to obtain ligand migration free energy profiles. The formation of the heme-Fe(II)-NO bond took into consideration the iron atom displacement from the heme plane. The ligand migration is almost unhindered, and the low rate constant for NO binding is due to the large displacement of the Fe(II) atom with respect to the heme plane responsible for the barrier for the Fe(II)-NO bond formation. In addition, we investigated the weakening and breaking of the proximal His-Fe(II) bond, observed experimentally upon NO binding, by means of a combination of classical molecular dynamics simulations and quantum-classical (QM-MM) optimizations. In both human and M. tuberculosis Nbs, a stable alternative conformation of the proximal His residue interacting with a network of water molecules was observed.
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Affiliation(s)
- Andresa Messias
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Intendente Güiraldes 2160, C1428EHA Buenos Aires, Argentina; CONICET - Universidad de Buenos Aires, Instituto de Química-Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina
| | | | - Diego Alonso de Armiño
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Intendente Güiraldes 2160, C1428EHA Buenos Aires, Argentina; CONICET - Universidad de Buenos Aires, Instituto de Química-Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina
| | - Giovanna De Simone
- Department of Sciences, Roma Tre University, Viale G. Marconi 446, I-00146 Roma, Italy
| | - Fabio Polticelli
- Department of Sciences, Roma Tre University, Viale G. Marconi 446, I-00146 Roma, Italy
| | | | - Paolo Ascenzi
- Accademia Nazionale dei Lincei, Via della Lungara 10, 00165 Roma, Italy
| | - Darío A Estrin
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Intendente Güiraldes 2160, C1428EHA Buenos Aires, Argentina; CONICET - Universidad de Buenos Aires, Instituto de Química-Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina.
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Turilli-Ghisolfi ES, Lualdi M, Fasano M. Ligand-Based Regulation of Dynamics and Reactivity of Hemoproteins. Biomolecules 2023; 13:683. [PMID: 37189430 PMCID: PMC10135655 DOI: 10.3390/biom13040683] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/14/2023] [Accepted: 04/15/2023] [Indexed: 05/17/2023] Open
Abstract
Hemoproteins include several heme-binding proteins with distinct structure and function. The presence of the heme group confers specific reactivity and spectroscopic properties to hemoproteins. In this review, we provide an overview of five families of hemoproteins in terms of dynamics and reactivity. First, we describe how ligands modulate cooperativity and reactivity in globins, such as myoglobin and hemoglobin. Second, we move on to another family of hemoproteins devoted to electron transport, such as cytochromes. Later, we consider heme-based reactivity in hemopexin, the main heme-scavenging protein. Then, we focus on heme-albumin, a chronosteric hemoprotein with peculiar spectroscopic and enzymatic properties. Eventually, we analyze the reactivity and dynamics of the most recently discovered family of hemoproteins, i.e., nitrobindins.
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Affiliation(s)
| | | | - Mauro Fasano
- Department of Science and High Technology, University of Insubria, 22100 Como, Italy
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De Simone G, di Masi A, Tundo GR, Coletta M, Ascenzi P. Nitrite Reductase Activity of Ferrous Nitrobindins: A Comparative Study. Int J Mol Sci 2023; 24:ijms24076553. [PMID: 37047528 PMCID: PMC10094804 DOI: 10.3390/ijms24076553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/17/2023] [Accepted: 03/20/2023] [Indexed: 04/03/2023] Open
Abstract
Nitrobindins (Nbs) are all-β-barrel heme proteins spanning from bacteria to Homo sapiens. They inactivate reactive nitrogen species by sequestering NO, converting NO to HNO2, and promoting peroxynitrite isomerization to NO3−. Here, the nitrite reductase activity of Nb(II) from Mycobacterium tuberculosis (Mt-Nb(II)), Arabidopsis thaliana (At-Nb(II)), Danio rerio (Dr-Nb(II)), and Homo sapiens (Hs-Nb(II)) is reported. This activity is crucial for the in vivo production of NO, and thus for the regulation of blood pressure, being of the utmost importance for the blood supply to poorly oxygenated tissues, such as the eye retina. At pH 7.3 and 20.0 °C, the values of the second-order rate constants (i.e., kon) for the reduction of NO2− to NO and the concomitant formation of nitrosylated Mt-Nb(II), At-Nb(II), Dr-Nb(II), and Hs-Nb(II) (Nb(II)-NO) were 7.6 M−1 s−1, 9.3 M−1 s−1, 1.4 × 101 M−1 s−1, and 5.8 M−1 s−1, respectively. The values of kon increased linearly with decreasing pH, thus indicating that the NO2−-based conversion of Nb(II) to Nb(II)-NO requires the involvement of one proton. These results represent the first evidence for the NO2 reductase activity of Nbs(II), strongly supporting the view that Nbs are involved in NO metabolism. Interestingly, the nitrite reductase reactivity of all-β-barrel Nbs and of all-α-helical globins (e.g., myoglobin) was very similar despite the very different three-dimensional fold; however, differences between all-α-helical globins and all-β-barrel Nbs suggest that nitrite reductase activity appears to be controlled by distal steric barriers, even though a more complex regulatory mechanism can be also envisaged.
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Affiliation(s)
| | | | - Grazia R. Tundo
- Dipartimento di Scienze Cliniche e Medicina Traslazionale, Università di Roma Tor Vergata, 00133 Roma, Italy
| | | | - Paolo Ascenzi
- Laboratorio Interdipartimentale di Microscopia Elettronica, Università Roma Tre, 00146 Roma, Italy
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Nitrosylation of ferric zebrafish nitrobindin: A spectroscopic, kinetic, and thermodynamic study. J Inorg Biochem 2022; 237:111996. [PMID: 36150290 DOI: 10.1016/j.jinorgbio.2022.111996] [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: 07/06/2022] [Revised: 08/30/2022] [Accepted: 09/10/2022] [Indexed: 01/18/2023]
Abstract
Nitrobindins (Nbs) are all-β-barrel heme-proteins present in all the living kingdoms. Nbs inactivate reactive nitrogen species by sequestering NO, converting NO to HNO2, and isomerizing peroxynitrite to NO3- and NO2-. Here, the spectroscopic characterization of ferric Danio rerio Nb (Dr-Nb(III)) and NO scavenging through the reductive nitrosylation of the metal center are reported, both processes being relevant for the regulation of blood flow in fishes through poorly oxygenated tissues, such as retina. Both UV-Vis and resonance Raman spectroscopies indicate that Dr-Nb(III) is a mixture of a six-coordinated aquo- and a five-coordinated species, whose relative abundancies depend on pH. At pH ≤ 7.0, Dr-Nb(III) binds reversibly NO, whereas at pH ≥ 7.8 NO induces the conversion of Dr-Nb(III) to Dr-Nb(II)-NO. The conversion of Dr-Nb(III) to Dr-Nb(II)-NO is a monophasic process, suggesting that the formation of the transient Dr-Nb(III)-NO species is lost in the mixing time of the rapid-mixing stopped-flow apparatus (∼ 1.5 ms). The pseudo-first-order rate constant for the reductive nitrosylation of Dr-Nb(III) is not linearly dependent on the NO concentration but tends to level off. Values of the rate-limiting constant (i.e., klim) increase linearly with the OH- concentration, indicating that the conversion of Dr-Nb(III) to Dr-Nb(II)-NO is limited by the OH--based catalysis. From the dependence of klim on [OH-], the value of the second-order rate constant kOH- was obtained (5.2 × 103 M-1 s-1). Reductive nitrosylation of Dr-Nb(III) leads to the inactivation of two NO molecules: one being converted to HNO2, and the other being tightly bound to the heme-Fe(II) atom.
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Strategies of Pathogens to Escape from NO-Based Host Defense. Antioxidants (Basel) 2022; 11:antiox11112176. [DOI: 10.3390/antiox11112176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 10/27/2022] [Indexed: 11/06/2022] Open
Abstract
Nitric oxide (NO) is an essential signaling molecule present in most living organisms including bacteria, fungi, plants, and animals. NO participates in a wide range of biological processes including vasomotor tone, neurotransmission, and immune response. However, NO is highly reactive and can give rise to reactive nitrogen and oxygen species that, in turn, can modify a broad range of biomolecules. Much evidence supports the critical role of NO in the virulence and replication of viruses, bacteria, protozoan, metazoan, and fungi, thus representing a general mechanism of host defense. However, pathogens have developed different mechanisms to elude the host NO and to protect themselves against oxidative and nitrosative stress. Here, the strategies evolved by viruses, bacteria, protozoan, metazoan, and fungi to escape from the NO-based host defense are overviewed.
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De Simone G, Fattibene P, Sebastiani F, Smulevich G, Coletta M, Ascenzi P. Dissociation of the proximal His-Fe bond upon NO binding to ferrous zebrafish nitrobindin. J Inorg Biochem 2022; 236:111962. [PMID: 36075159 DOI: 10.1016/j.jinorgbio.2022.111962] [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: 06/22/2022] [Revised: 07/22/2022] [Accepted: 08/09/2022] [Indexed: 12/15/2022]
Abstract
Nitrobindins (Nbs) are all-β-barrel heme-proteins present in prokaryotes and eukaryotes. Although the physiological role(s) of Nbs are still unclear, it has been postulated that they are involved in the NO/O2 metabolism, which is particularly relevant in fishes for the oxygen supply. Here, the reactivity of ferrous Danio rerio Nb (Dr-Nb(II)) towards NO has been investigated from the spectroscopic and kinetic viewpoints and compared with those of Mycobacterium tuberculosis Nb, Arabidopsis thaliana Nb, Homo sapiens Nb, and Equus ferus caballus myoglobin. Between pH 5.5 and 9.1 at 22.0 °C, Dr-Nb(II) nitrosylation is a monophasic process; values of the second-order rate constant for Dr-Nb(II) nitrosylation and of the first-order rate constant for Dr-Nb(II)-NO denitrosylation are pH-independent ranging between 1.6 × 106 M-1 s-1 and 2.3 × 106 M-1 s-1 and between 5.3 × 10-2 s-1 and 8.2 × 10-2 s-1, respectively. Interestingly, both UV-Vis and EPR spectroscopies indicate that the heme-Fe(II) atom of Dr-Nb(II)-NO is five-coordinated. Kinetics of Dr-Nb(II) nitrosylation may reflect the ligand accessibility to the metal center, which is likely impaired by the crowded network of water molecules which shields the heme pocket from the bulk solvent. On the other hand, kinetics of Dr-Nb(II)-NO denitrosylation may reflect an easy pathway for the ligand escape into the outer solvent.
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Affiliation(s)
| | - Paola Fattibene
- Servizio Grandi Strumentazioni e Core Facilities, Istituto Superiore di Sanità, Roma, Italy
| | | | | | | | - Paolo Ascenzi
- Laboratorio Interdipartimentale di Microscopia Elettronica, Università Roma Tre, 00146 Roma, Italy.
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De Simone G, Coletta A, di Masi A, Coletta M, Ascenzi P. The Balancing of Peroxynitrite Detoxification between Ferric Heme-Proteins and CO2: The Case of Zebrafish Nitrobindin. Antioxidants (Basel) 2022; 11:antiox11101932. [PMID: 36290653 PMCID: PMC9599043 DOI: 10.3390/antiox11101932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 11/16/2022] Open
Abstract
Nitrobindins (Nbs) are all-β-barrel heme proteins and are present in prokaryotes and eukaryotes. Although their function(s) is still obscure, Nbs trap NO and inactivate peroxynitrite. Here, the kinetics of peroxynitrite scavenging by ferric Danio rerio Nb (Dr-Nb(III)) in the absence and presence of CO2 is reported. The Dr-Nb(III)-catalyzed scavenging of peroxynitrite is facilitated by a low pH, indicating that the heme protein interacts preferentially with peroxynitrous acid, leading to the formation of nitrate (~91%) and nitrite (~9%). The physiological levels of CO2 dramatically facilitate the spontaneous decay of peroxynitrite, overwhelming the scavenging activity of Dr-Nb(III). The effect of Dr-Nb(III) on the peroxynitrite-induced nitration of L-tyrosine was also investigated. Dr-Nb(III) inhibits the peroxynitrite-mediated nitration of free L-tyrosine, while, in the presence of CO2, Dr-Nb(III) does not impair nitro-L-tyrosine formation. The comparative analysis of the present results with data reported in the literature indicates that, to act as efficient peroxynitrite scavengers in vivo, i.e., in the presence of physiological levels of CO2, the ferric heme protein concentration must be higher than 10−4 M. Thus, only the circulating ferric hemoglobin levels appear to be high enough to efficiently compete with CO2/HCO3− in peroxynitrite inactivation. The present results are of the utmost importance for tissues, like the eye retina in fish, where blood circulation is critical for adaptation to diving conditions.
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Affiliation(s)
| | - Andrea Coletta
- Dipartimento di Scienze, Università Roma Tre, 00146 Roma, Italy
| | | | - Massimo Coletta
- IRCCS Fondazione Bietti, 00198 Roma, Italy
- Correspondence: (M.C.); (P.A.)
| | - Paolo Ascenzi
- Dipartimento di Scienze, Università Roma Tre, 00146 Roma, Italy
- Correspondence: (M.C.); (P.A.)
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di Masi A, Sessa RL, Cerrato Y, Pastore G, Guantario B, Ambra R, Di Gioacchino M, Sodo A, Verri M, Crucitti P, Longo F, Naciu AM, Palermo A, Taffon C, Acconcia F, Bianchi F, Ascenzi P, Ricci MA, Crescenzi A. Unraveling the Effects of Carotenoids Accumulation in Human Papillary Thyroid Carcinoma. Antioxidants (Basel) 2022; 11:antiox11081463. [PMID: 36009182 PMCID: PMC9405418 DOI: 10.3390/antiox11081463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 07/12/2022] [Accepted: 07/20/2022] [Indexed: 02/01/2023] Open
Abstract
Among the thyroid cancers, papillary thyroid cancer (PTC) accounts for 90% of the cases. In addition to the necessity to identify new targets for PTC treatment, early diagnosis and management are highly demanded. Previous data indicated that the multivariate statistical analysis of the Raman spectra allows the discrimination of healthy tissues from PTC ones; this is characterized by bands typical of carotenoids. Here, we dissected the molecular effects of carotenoid accumulation in PTC patients by analyzing whether they were required to provide increased retinoic acid (RA) synthesis and signaling and/or to sustain antioxidant functions. HPLC analysis revealed the lack of a significant difference in the overall content of carotenoids. For this reason, we wondered whether the carotenoid accumulation in PTC patients could be related to vitamin A derivative retinoic acid (RA) biosynthesis and, consequently, the RA-related pathway activation. The transcriptomic analysis performed using a dedicated PCR array revealed a significant downregulation of RA-related pathways in PTCs, suggesting that the carotenoid accumulation in PTC could be related to a lower metabolic conversion into RA compared to that of healthy tissues. In addition, the gene expression profile of 474 PTC cases previously published in the framework of the Cancer Genome Atlas (TGCA) project was examined by hierarchical clustering and heatmap analyses. This metanalysis study indicated that the RA-related pathways resulted in being significantly downregulated in PTCs and being associated with the follicular variant of PTC (FV-PTC). To assess whether the possible fate of the carotenoids accumulated in PTCs is associated with the oxidative stress response, the expression of enzymes involved in ROS scavenging was checked. An increased oxidative stress status and a reduced antioxidant defense response were observed in PTCs compared to matched healthy thyroids; this was possibly associated with the prooxidant effects of high levels of carotenoids. Finally, the DepMap datasets were used to profile the levels of 225 metabolites in 12 thyroid cancer cell lines. The results obtained suggested that the high carotenoid content in PTCs correlates with tryptophan metabolism. This pilot provided novel possible markers and possible therapeutic targets for PTC diagnosis and therapy. For the future, a larger study including a higher number of PTC patients will be necessary to further validate the molecular data reported here.
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Affiliation(s)
- Alessandra di Masi
- Department of Sciences, Roma Tre University, 00146 Rome, Italy; (R.L.S.); (Y.C.); (M.D.G.); (A.S.); (F.A.); (P.A.); (M.A.R.)
- Correspondence: ; Tel.: +39-06-57336363
| | - Rosario Luigi Sessa
- Department of Sciences, Roma Tre University, 00146 Rome, Italy; (R.L.S.); (Y.C.); (M.D.G.); (A.S.); (F.A.); (P.A.); (M.A.R.)
| | - Ylenia Cerrato
- Department of Sciences, Roma Tre University, 00146 Rome, Italy; (R.L.S.); (Y.C.); (M.D.G.); (A.S.); (F.A.); (P.A.); (M.A.R.)
| | - Gianni Pastore
- CREA (Council for Agricultural Research and Economics), Research Centre for Food and Nutrition, 00178 Rome, Italy; (G.P.); (B.G.); (R.A.)
| | - Barbara Guantario
- CREA (Council for Agricultural Research and Economics), Research Centre for Food and Nutrition, 00178 Rome, Italy; (G.P.); (B.G.); (R.A.)
| | - Roberto Ambra
- CREA (Council for Agricultural Research and Economics), Research Centre for Food and Nutrition, 00178 Rome, Italy; (G.P.); (B.G.); (R.A.)
| | - Michael Di Gioacchino
- Department of Sciences, Roma Tre University, 00146 Rome, Italy; (R.L.S.); (Y.C.); (M.D.G.); (A.S.); (F.A.); (P.A.); (M.A.R.)
| | - Armida Sodo
- Department of Sciences, Roma Tre University, 00146 Rome, Italy; (R.L.S.); (Y.C.); (M.D.G.); (A.S.); (F.A.); (P.A.); (M.A.R.)
| | - Martina Verri
- Pathology Unit, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (M.V.); (C.T.); (A.C.)
| | - Pierfilippo Crucitti
- Unit of Thoracic Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (P.C.); (F.L.)
| | - Filippo Longo
- Unit of Thoracic Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (P.C.); (F.L.)
| | - Anda Mihaela Naciu
- Unit of Metabolic Bone and Thyroid Disorders, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (A.M.N.); (A.P.)
| | - Andrea Palermo
- Unit of Metabolic Bone and Thyroid Disorders, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (A.M.N.); (A.P.)
| | - Chiara Taffon
- Pathology Unit, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (M.V.); (C.T.); (A.C.)
| | - Filippo Acconcia
- Department of Sciences, Roma Tre University, 00146 Rome, Italy; (R.L.S.); (Y.C.); (M.D.G.); (A.S.); (F.A.); (P.A.); (M.A.R.)
| | - Fabrizio Bianchi
- Cancer Biomarkers Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, FG, Italy;
| | - Paolo Ascenzi
- Department of Sciences, Roma Tre University, 00146 Rome, Italy; (R.L.S.); (Y.C.); (M.D.G.); (A.S.); (F.A.); (P.A.); (M.A.R.)
| | - Maria Antonietta Ricci
- Department of Sciences, Roma Tre University, 00146 Rome, Italy; (R.L.S.); (Y.C.); (M.D.G.); (A.S.); (F.A.); (P.A.); (M.A.R.)
| | - Anna Crescenzi
- Pathology Unit, Fondazione Policlinico Universitario Campus Bio-Medico, 00128 Rome, Italy; (M.V.); (C.T.); (A.C.)
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11
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Hydroxylamine-induced oxidation of ferrous nitrobindins. J Biol Inorg Chem 2022; 27:443-453. [PMID: 35543759 DOI: 10.1007/s00775-022-01940-9] [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: 12/20/2021] [Accepted: 04/21/2022] [Indexed: 12/19/2022]
Abstract
Hemoglobin and myoglobin are generally taken as molecular models of all-α-helical heme-proteins. On the other hand, nitrophorins and nitrobindins (Nb), which are arranged in 8 and 10 β-strands, respectively, represent the molecular models of all-β-barrel heme-proteins. Here, kinetics of the hydroxylamine- (HA-) mediated oxidation of ferrous Mycobacterium tuberculosis, Arabidopsis thaliana, and Homo sapiens nitrobindins (Mt-Nb(II), At-Nb(II), and Hs-Nb(II), respectively), at pH 7.0 and 20.0 °C, are reported. Of note, HA displays antibacterial properties and is a good candidate for the treatment and/or prevention of reactive nitrogen species- (RNS-) linked aging-related pathologies, such as macular degeneration. Under anaerobic conditions, mixing the Mt-Nb(II), At-Nb(II), and Hs-Nb(II) solutions with the HA solutions brings about absorbance spectral changes reflecting the formation of the ferric derivative (i.e., Mt-Nb(III), At-Nb(III), and Hs-Nb(III), respectively). Values of the second order rate constant for the HA-mediated oxidation of Mt-Nb(II), At-Nb(II), and Hs-Nb(II) are 1.1 × 104 M-1 s-1, 6.5 × 104 M-1 s-1, and 2.2 × 104 M-1 s-1, respectively. Moreover, the HA:Nb(II) stoichiometry is 1:2 as reported for ferrous deoxygenated and carbonylated all-α-helical heme-proteins. A comparative look of the HA reduction kinetics by several ferrous heme-proteins suggests that an important role might be played by residues (such as His or Tyr) in the proximity of the heme-Fe atom either coordinating it or not. In this respect, Nbs seem to exploit somewhat different structural aspects, indicating that redox mechanisms for the heme-Fe(II)-to-heme-Fe(III) conversion might differ between all-α-helical and all-β-barrel heme-proteins.
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12
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Hurst CD, Cheng G, Platt FM, Castro MA, Marzouka NADS, Eriksson P, Black EV, Alder O, Lawson AR, Lindskrog SV, Burns JE, Jain S, Roulson JA, Brown JC, Koster J, Robertson AG, Martincorena I, Dyrskjøt L, Höglund M, Knowles MA. Stage-stratified molecular profiling of non-muscle-invasive bladder cancer enhances biological, clinical, and therapeutic insight. Cell Rep Med 2021; 2:100472. [PMID: 35028613 PMCID: PMC8714941 DOI: 10.1016/j.xcrm.2021.100472] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 08/09/2021] [Accepted: 11/18/2021] [Indexed: 12/26/2022]
Abstract
Understanding the molecular determinants that underpin the clinical heterogeneity of non-muscle-invasive bladder cancer (NMIBC) is essential for prognostication and therapy development. Stage T1 disease in particular presents a high risk of progression and requires improved understanding. We present a detailed multi-omics study containing gene expression, copy number, and mutational profiles that show relationships to immune infiltration, disease recurrence, and progression to muscle invasion. We compare expression and genomic subtypes derived from all NMIBCs with those derived from the individual disease stages Ta and T1. We show that sufficient molecular heterogeneity exists within the separate stages to allow subclassification and that this is more clinically meaningful for stage T1 disease than that derived from all NMIBCs. This provides improved biological understanding and identifies subtypes of T1 tumors that may benefit from chemo- or immunotherapy.
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Affiliation(s)
- Carolyn D. Hurst
- Division of Molecular Medicine, Leeds Institute of Medical Research at St James’s, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Guo Cheng
- Division of Molecular Medicine, Leeds Institute of Medical Research at St James’s, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Fiona M. Platt
- Division of Molecular Medicine, Leeds Institute of Medical Research at St James’s, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Mauro A.A. Castro
- Bioinformatics and Systems Biology Laboratory, Federal University of Paraná, Curitiba, Brazil
| | | | - Pontus Eriksson
- Division of Oncology, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Emma V.I. Black
- Division of Molecular Medicine, Leeds Institute of Medical Research at St James’s, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Olivia Alder
- Division of Molecular Medicine, Leeds Institute of Medical Research at St James’s, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Andrew R.J. Lawson
- Cancer, Ageing and Somatic Mutation Programme, Wellcome Sanger Institute, Hinxton CB10 1SA, UK
| | - Sia V. Lindskrog
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Julie E. Burns
- Division of Molecular Medicine, Leeds Institute of Medical Research at St James’s, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Sunjay Jain
- Pyrah Department of Urology, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Jo-An Roulson
- Department of Histopathology, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Joanne C. Brown
- Division of Molecular Medicine, Leeds Institute of Medical Research at St James’s, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Jan Koster
- Laboratory for Experimental Oncology and Radiobiology, Center for Experimental and Molecular Medicine, Amsterdam University Medical Centers, University of Amsterdam, Cancer Center Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands
| | - A. Gordon Robertson
- Canada’s Michael Smith Genome Sciences Center, BC Cancer, Vancouver, BC V5Z 4S6, Canada
| | - Inigo Martincorena
- Cancer, Ageing and Somatic Mutation Programme, Wellcome Sanger Institute, Hinxton CB10 1SA, UK
| | - Lars Dyrskjøt
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Mattias Höglund
- Division of Oncology, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Margaret A. Knowles
- Division of Molecular Medicine, Leeds Institute of Medical Research at St James’s, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK
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13
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De Simone G, Sbardella D, Oddone F, Pesce A, Coletta M, Ascenzi P. Structural and (Pseudo-)Enzymatic Properties of Neuroglobin: Its Possible Role in Neuroprotection. Cells 2021; 10:cells10123366. [PMID: 34943874 PMCID: PMC8699588 DOI: 10.3390/cells10123366] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/20/2021] [Accepted: 11/23/2021] [Indexed: 12/17/2022] Open
Abstract
Neuroglobin (Ngb), the third member of the globin family, was discovered in human and murine brains in 2000. This monomeric globin is structurally similar to myoglobin (Mb) and hemoglobin (Hb) α and β subunits, but it hosts a bis-histidyl six-coordinated heme-Fe atom. Therefore, the heme-based reactivity of Ngb is modulated by the dissociation of the distal HisE7-heme-Fe bond, which reflects in turn the redox state of the cell. The high Ngb levels (~100–200 μM) present in the retinal ganglion cell layer and in the optic nerve facilitate the O2 buffer and delivery. In contrast, the very low levels of Ngb (~1 μM) in most tissues and organs support (pseudo-)enzymatic properties including NO/O2 metabolism, peroxynitrite and free radical scavenging, nitrite, hydroxylamine, hydrogen sulfide reduction, and the nitration of aromatic compounds. Here, structural and (pseudo-)enzymatic properties of Ngb, which are at the root of tissue and organ protection, are reviewed, envisaging a possible role in the protection from neuronal degeneration of the retina and the optic nerve.
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Affiliation(s)
- Giovanna De Simone
- Dipartimento di Scienze, Università Roma Tre, Viale Marconi 446, 00146 Roma, Italy;
| | | | | | - Alessandra Pesce
- Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, 16100 Genova, Italy;
| | - Massimo Coletta
- IRCCS Fondazione Bietti, 00198 Roma, Italy; (D.S.); (F.O.)
- Dipartmento di Scienze Cliniche e Medicina Traslazionale, Università di Roma “Tor Vergata”, Via Montpellier 1, 00133 Roma, Italy
- Correspondence: (M.C.); (P.A.); Tel.: +39-06-72596365 (M.C.); +39-06-57336321 (P.A.)
| | - Paolo Ascenzi
- Dipartimento di Scienze, Università Roma Tre, Viale Marconi 446, 00146 Roma, Italy;
- Accademia Nazionale dei Lincei, Via della Lungara 10, 00165 Roma, Italy
- Unità di Neuroendocrinologia, Metabolismo e Neurofarmacologia, IRCSS Fondazione Santa Lucia, 00179 Roma, Italy
- Correspondence: (M.C.); (P.A.); Tel.: +39-06-72596365 (M.C.); +39-06-57336321 (P.A.)
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14
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De Simone G, di Masi A, Fattibene P, Ciaccio C, Platas-Iglesias C, Coletta M, Pesce A, Ascenzi P. Oxygen-mediated oxidation of ferrous nitrosylated nitrobindins. J Inorg Biochem 2021; 224:111579. [PMID: 34479003 DOI: 10.1016/j.jinorgbio.2021.111579] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 07/23/2021] [Accepted: 08/10/2021] [Indexed: 01/25/2023]
Abstract
The O2-mediated oxidation of all-β-barrel ferrous nitrosylated nitrobindin from Arabidopsis thaliana (At-Nb(II)-NO), Mycobacterium tuberculosis (Mt-Nb(II)-NO), and Homo sapiens (Hs-Nb(II)-NO) to ferric derivative (At-Nb(III), Mt-Nb(III), and Hs-Nb(III), respectively) has been investigated at pH 7.0 and 20.0 °C. Unlike ferrous nitrosylated horse myoglobin, human serum heme-albumin and human hemoglobin, the process in Nb(II)-NO is mono-exponential and linearly dependent on the O2 concentration, displaying a bimolecular behavior, characterized by kon = (6.3 ± 0.8) × 103 M-1 s-1, (1.4 ± 0.2) × 103 M-1 s-1, and (3.9 ± 0.5) × 103 M-1 s-1 for At-Nb(II)-NO, Mt-Nb(II)-NO, and Hs-Nb(II)-NO, respectively. No intermediate is detected, indicating that the O2 reaction with Nb(II)-NO is the rate-limiting step and that the subsequent conversion of the heme-Fe(III)-N(O)OO- species (i.e., N-bound peroxynitrite to heme-Fe(III)) to heme-Fe(III) and NO3- is much faster. A similar mechanism can be invoked for ferrous nitrosylated human neuroglobin and rabbit hemopexin, in which the heme-Fe(III)-N(O)OO- species is formed as well, although the rate-limiting step seems represented by the reshaping of the six-coordinated heme-Fe(III) complex. Although At-Nb(II)-NO and Mt-Nb(II)-NO are partially (while Hs-Nb(II)-NO is almost completely) penta-coordinated, density functional theory (DFT) calculations rule out that the cleavage of the proximal heme-Fe-His bond in Nb(II)-NO is responsible for the more stable heme-Fe(III)-N(O)OO- species. Moreover, the oxidation of the penta-coordinated heme-Fe(II)-NO adduct does not depend on O2 binding at the proximal side of the metal center. These features may instead reflect the peculiarity of Nb folding and of the heme environment, with a reduced steric constraint for the formation of the heme-Fe(III)-N(O)OO- complex.
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Affiliation(s)
- Giovanna De Simone
- Department of Sciences, Roma Tre University, Viale Guglielmo Marconi 446, 00146 Roma, Italy
| | - Alessandra di Masi
- Department of Sciences, Roma Tre University, Viale Guglielmo Marconi 446, 00146 Roma, Italy
| | - Paola Fattibene
- Technical Scientific Service and Core Facilities, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Roma, Italy
| | - Chiara Ciaccio
- Department of Clinical Sciences and Translational Medicine, University of Roma "Tor Vergata", Via Montpellier 1, I-00133 Roma, Italy
| | - Carlos Platas-Iglesias
- Centro de Investigatiòns Cientìficas Avanzadas (CIA), Departamento de Quìmica, Facultade de Ciencias, Universidad da Coruña, 15071 A Coruña, Galicia, Spain
| | - Massimo Coletta
- Department of Clinical Sciences and Translational Medicine, University of Roma "Tor Vergata", Via Montpellier 1, I-00133 Roma, Italy
| | - Alessandra Pesce
- Department of Physics, University of Genova, Via Dodecaneso 33, 16100 Genova, Italy
| | - Paolo Ascenzi
- Department of Sciences, Roma Tre University, Viale Guglielmo Marconi 446, 00146 Roma, Italy; Interdepartmental Laboratory of Electron Microscopy, Roma Tre University, Via della Vasca Navale 79, I-00146 Roma, Italy.
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15
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Mycobacterial and Human Ferrous Nitrobindins: Spectroscopic and Reactivity Properties. Int J Mol Sci 2021; 22:ijms22041674. [PMID: 33562340 PMCID: PMC7915275 DOI: 10.3390/ijms22041674] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/26/2021] [Accepted: 02/01/2021] [Indexed: 12/24/2022] Open
Abstract
Structural and functional properties of ferrous Mycobacterium tuberculosis (Mt-Nb) and human (Hs-Nb) nitrobindins (Nbs) were investigated. At pH 7.0 and 25.0 °C, the unliganded Fe(II) species is penta-coordinated and unlike most other hemoproteins no pH-dependence of its coordination was detected over the pH range between 2.2 and 7.0. Further, despite a very open distal side of the heme pocket (as also indicated by the vanishingly small geminate recombination of CO for both Nbs), which exposes the heme pocket to the bulk solvent, their reactivity toward ligands, such as CO and NO, is significantly slower than in most hemoproteins, envisaging either a proximal barrier for ligand binding and/or crowding of H2O molecules in the distal side of the heme pocket which impairs ligand binding to the heme Fe-atom. On the other hand, liganded species display already at pH 7.0 and 25 °C a severe weakening (in the case of CO) and a cleavage (in the case of NO) of the proximal Fe-His bond, suggesting that the ligand-linked movement of the Fe(II) atom onto the heme plane brings about a marked lengthening of the proximal Fe-imidazole bond, eventually leading to its rupture. This structural evidence is accompanied by a marked enhancement of both ligands dissociation rate constants. As a whole, these data clearly indicate that structural–functional relationships in Nbs strongly differ from what observed in mammalian and truncated hemoproteins, suggesting that Nbs play a functional role clearly distinct from other eukaryotic and prokaryotic hemoproteins.
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16
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NO Scavenging through Reductive Nitrosylation of Ferric Mycobacterium tuberculosis and Homo sapiens Nitrobindins. Int J Mol Sci 2020; 21:ijms21249395. [PMID: 33321752 PMCID: PMC7763097 DOI: 10.3390/ijms21249395] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/24/2020] [Accepted: 12/01/2020] [Indexed: 11/17/2022] Open
Abstract
Ferric nitrobindins (Nbs) selectively bind NO and catalyze the conversion of peroxynitrite to nitrate. In this study, we show that NO scavenging occurs through the reductive nitrosylation of ferric Mycobacterium tuberculosis and Homo sapiens nitrobindins (Mt-Nb(III) and Hs-Nb(III), respectively). The conversion of Mt-Nb(III) and Hs-Nb(III) to Mt-Nb(II)-NO and Hs-Nb(II)-NO, respectively, is a monophasic process, suggesting that over the explored NO concentration range (between 2.5 × 10−5 and 1.0 × 10−3 M), NO binding is lost in the mixing time (i.e., NOkon ≥ 1.0 × 106 M−1 s−1). The pseudo-first-order rate constant for the reductive nitrosylation of Mt-Nb(III) and Hs-Nb(III) (i.e., k) is not linearly dependent on the NO concentration but tends to level off, with a rate-limiting step (i.e., klim) whose values increase linearly with [OH−]. This indicates that the conversion of Mt-Nb(III) and Hs-Nb(III) to Mt-Nb(II)-NO and Hs-Nb(II)-NO, respectively, is limited by the OH−-based catalysis. From the dependence of klim on [OH−], the values of the second-order rate constant kOH− for the reductive nitrosylation of Mt-Nb(III)-NO and Hs-Nb(III)-NO were obtained (4.9 (±0.5) × 103 M−1 s−1 and 6.9 (±0.8) × 103 M−1 s−1, respectively). This process leads to the inactivation of two NO molecules: one being converted to HNO2 and another being tightly bound to the ferrous heme-Fe(II) atom.
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