1
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Zámocký M, Hofbauer S, Gabler T, Furtmüller PG. The Molecular Evolution, Structure, and Function of Coproporphyrinogen Oxidase and Protoporphyrinogen Oxidase in Prokaryotes. BIOLOGY 2023; 12:1527. [PMID: 38132353 PMCID: PMC10740692 DOI: 10.3390/biology12121527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/08/2023] [Accepted: 12/11/2023] [Indexed: 12/23/2023]
Abstract
Coproporphyrinogen oxidase (CgoX) and protoporphyrinogen oxidase (PgoX) catalyze the oxidation of the flexible cyclic tetrapyrrole of porphyrinogen compounds into fully conjugated, planar macrocyclic porphyrin compounds during heme biosynthesis. These enzymes are activated via different pathways. CgoX oxidizes coproporphyrinogen III to coproporphyrin III in the coproporphyrin-dependent pathway, whereas PgoX oxidizes protoporphyrinogen IX to protoporphyrin IX in the penultimate step of the protoporphyrin-dependent pathway. The phylogenetic analysis presented herein demonstrates a clear differentiation between the two enzyme classes, as evidenced by the clustering of sequences in distinct clades, and it shows that, at the origin of porphyrinogen-type oxidase evolution, PgoXs from cyanobacteria were found, which were noticeably separated from descendant PgoX representatives of Deltaproteobacteria and all later PgoX variants, leading to many eukaryotic clades. CgoX sequences originating from the monoderm Actinomycetota and Bacillota were well separated from the predecessor clades containing PgoX types and represent a peculiar type of gene speciation. The structural similarities and differences between these two oxidases are discussed based on their protein sequence alignment and a structural comparison.
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Affiliation(s)
- Marcel Zámocký
- Laboratory of Phylogenomic Ecology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, SK-84551 Bratislava, Slovakia;
- Department of Inorganic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská Dolina, Ilkovičova 6, SK-84215 Bratislava, Slovakia
| | - Stefan Hofbauer
- Institute of Biochemistry, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, A-1190 Vienna, Austria; (S.H.); (T.G.)
| | - Thomas Gabler
- Institute of Biochemistry, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, A-1190 Vienna, Austria; (S.H.); (T.G.)
| | - Paul G. Furtmüller
- Institute of Biochemistry, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, A-1190 Vienna, Austria; (S.H.); (T.G.)
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2
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Patil G, Michlits H, Furtmüller PG, Hofbauer S. Reactivity of Coproheme Decarboxylase with Monovinyl, Monopropionate Deuteroheme. Biomolecules 2023; 13:946. [PMID: 37371526 PMCID: PMC10296651 DOI: 10.3390/biom13060946] [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: 04/28/2023] [Revised: 05/23/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
Coproheme decarboxylases (ChdCs) are terminal enzymes of the coproporphyrin-dependent heme biosynthetic pathway. In this reaction, two propionate groups are cleaved from the redox-active iron-containing substrate, coproheme, to form vinyl groups of the heme b product. The two decarboxylation reactions proceed sequentially, and a redox-active three-propionate porphyrin, called monovinyl, monopropionate deuteroheme (MMD), is transiently formed as an intermediate. While the reaction mechanism for the first part of the redox reaction, which is initiated by hydrogen peroxide, has been elucidated in some detail, the second part of this reaction, starting from MMD, has not been studied. Here, we report the optimization of enzymatic MMD production by ChdC and purification by reversed-phase chromatography. With the obtained MMD, we were able to study the second part of heme b formation by actinobacterial ChdC from Corynebacterium diphtheriae, starting with Compound I formation upon the addition of hydrogen peroxide. The results indicate that the second part of the decarboxylation reaction is analogous to the first part, although somewhat slower, which is explained by differences in the active site architecture and its H-bonding network. The results are discussed in terms of known kinetic and structural data and help to fill some mechanistic gaps in the overall reaction catalyzed by ChdCs.
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Affiliation(s)
| | | | | | - Stefan Hofbauer
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
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3
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Perez-Ortiz G, Sidda JD, Peate J, Ciccarelli D, Ding Y, Barry SM. Production of copropophyrin III, biliverdin and bilirubin by the rufomycin producer, Streptomyces atratus. Front Microbiol 2023; 14:1092166. [PMID: 37007481 PMCID: PMC10060970 DOI: 10.3389/fmicb.2023.1092166] [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: 11/07/2022] [Accepted: 01/31/2023] [Indexed: 03/18/2023] Open
Abstract
Heme is best known for its role as a versatile prosthetic group in prokaryotic and eukaryotic proteins with diverse biological functions including gas and electron transport, as well as a wide array of redox chemistry. However, free heme and related tetrapyrroles also have important roles in the cell. In several bacterial strains, heme biosynthetic precursors and degradation products have been proposed to function as signaling molecules, ion chelators, antioxidants and photoprotectants. While the uptake and degradation of heme by bacterial pathogens is well studied, less is understood about the physiological role of these processes and their products in non-pathogenic bacteria. Streptomyces are slow growing soil bacteria known for their extraordinary capacity to produce complex secondary metabolites, particularly many clinically used antibiotics. Here we report the unambiguous identification of three tetrapyrrole metabolites from heme metabolism, coproporphyrin III, biliverdin and bilirubin, in culture extracts of the rufomycin antibiotic producing Streptomyces atratus DSM41673. We propose that biliverdin and bilirubin may combat oxidative stress induced by nitric oxide production during rufomycin biosynthesis, and indicate the genes involved in their production. This is, to our knowledge, the first report of the production of all three of these tetrapyrroles by a Streptomycete.
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Affiliation(s)
| | | | | | | | | | - Sarah M. Barry
- Department of Chemistry, Faculty of Natural & Mathematical Sciences, King’s College London, London, United Kingdom
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4
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Sebastiani F, Baroni C, Patil G, Dali A, Becucci M, Hofbauer S, Smulevich G. The Role of the Hydrogen Bond Network in Maintaining Heme Pocket Stability and Protein Function Specificity of C. diphtheriae Coproheme Decarboxylase. Biomolecules 2023; 13:235. [PMID: 36830604 PMCID: PMC9953210 DOI: 10.3390/biom13020235] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 01/27/2023] Open
Abstract
Monoderm bacteria accumulate heme b via the coproporphyrin-dependent biosynthesis pathway. In the final step, in the presence of two molecules of H2O2, the propionate groups of coproheme at positions 2 and 4 are decarboxylated to form vinyl groups by coproheme decarboxylase (ChdC), in a stepwise process. Decarboxylation of propionate 2 produces an intermediate that rotates by 90° inside the protein pocket, bringing propionate 4 near the catalytic tyrosine, to allow the second decarboxylation step. The active site of ChdCs is stabilized by an extensive H-bond network involving water molecules, specific amino acid residues, and the propionate groups of the porphyrin. To evaluate the role of these H-bonds in the pocket stability and enzyme functionality, we characterized, via resonance Raman and electronic absorption spectroscopies, single and double mutants of the actinobacterial pathogen Corynebacterium diphtheriae ChdC complexed with coproheme and heme b. The selective elimination of the H-bond interactions between propionates 2, 4, 6, and 7 and the polar residues of the pocket allowed us to establish the role of each H-bond in the catalytic reaction and to follow the changes in the interactions from the substrate to the product.
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Affiliation(s)
- Federico Sebastiani
- Dipartimento di Chimica “Ugo Schiff”, DICUS, Università di Firenze, Via della Lastruccia 3-13, I-50019 Sesto Fiorentino, Italy
| | - Chiara Baroni
- Dipartimento di Chimica “Ugo Schiff”, DICUS, Università di Firenze, Via della Lastruccia 3-13, I-50019 Sesto Fiorentino, Italy
| | - Gaurav Patil
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Andrea Dali
- Dipartimento di Chimica “Ugo Schiff”, DICUS, Università di Firenze, Via della Lastruccia 3-13, I-50019 Sesto Fiorentino, Italy
| | - Maurizio Becucci
- Dipartimento di Chimica “Ugo Schiff”, DICUS, Università di Firenze, Via della Lastruccia 3-13, I-50019 Sesto Fiorentino, Italy
| | - Stefan Hofbauer
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Giulietta Smulevich
- Dipartimento di Chimica “Ugo Schiff”, DICUS, Università di Firenze, Via della Lastruccia 3-13, I-50019 Sesto Fiorentino, Italy
- INSTM Research Unit of Firenze, via della Lastruccia 3, I-50019 Sesto Fiorentino, Italy
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5
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Reorienting Mechanism of Harderoheme in Coproheme Decarboxylase-A Computational Study. Int J Mol Sci 2022; 23:ijms23052564. [PMID: 35269706 PMCID: PMC8910490 DOI: 10.3390/ijms23052564] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/16/2022] [Accepted: 02/23/2022] [Indexed: 02/06/2023] Open
Abstract
Coproheme decarboxylase (ChdC) is an important enzyme in the coproporphyrin-dependent pathway (CPD) of Gram-positive bacteria that decarboxylates coproheme on two propionates at position 2 and position 4 sequentially to generate heme b by using H2O2 as an oxidant. This work focused on the ChdC from Geobacillus stearothermophilus (GsChdC) to elucidate the mechanism of its sequential two-step decarboxylation of coproheme. The models of GsChdC in a complex with substrate and reaction intermediate were built to investigate the reorienting mechanism of harderoheme. Targeted molecular dynamics simulations on these models validated that harderoheme is able to rotate in the active site of GsChdC with a 19.06-kcal·mol-1 energy barrier after the first step of decarboxylation to bring the propionate at position 4 in proximity of Tyr145 to continue the second decarboxylation step. The harderoheme rotation mechanism is confirmed to be much easier than the release-rebinding mechanism. In the active site of GsChdC, Trp157 and Trp198 comprise a "gate" construction to regulate the clockwise rotation of the harderoheme. Lys149 plays a critical role in the rotation mechanism, which not only keeps the Trp157-Trp198 "gate" from being closed but also guides the propionate at position 4 through the gap between Trp157 and Trp198 through a salt bridge interaction.
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6
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Sebastiani F, Michlits H, Lier B, Becucci M, Furtmüller PG, Oostenbrink C, Obinger C, Hofbauer S, Smulevich G. Reaction intermediate rotation during the decarboxylation of coproheme to heme b in C. diphtheriae. Biophys J 2021; 120:3600-3614. [PMID: 34339636 PMCID: PMC8456308 DOI: 10.1016/j.bpj.2021.06.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 06/22/2021] [Accepted: 06/27/2021] [Indexed: 02/06/2023] Open
Abstract
Monoderm bacteria utilize coproheme decarboxylases (ChdCs) to generate heme b by a stepwise decarboxylation of two propionate groups of iron coproporphyrin III (coproheme), forming two vinyl groups. This work focuses on actinobacterial ChdC from Corynebacterium diphtheriae (CdChdC) to elucidate the hydrogen peroxide-mediated decarboxylation of coproheme via monovinyl monopropionyl deuteroheme (MMD) to heme b, with the principal aim being to understand the reorientation mechanism of MMD during turnover. Wild-type CdChdC and variants, namely H118A, H118F, and A207E, were studied by resonance Raman and ultraviolet-visible spectroscopy, mass spectrometry, and molecular dynamics simulations. As actinobacterial ChdCs use a histidine (H118) as a distal base, we studied the H118A and H118F variants to elucidate the effect of 1) the elimination of the proton acceptor and 2) steric constraints within the active site. The A207E variant mimics the proximal H-bonding network found in chlorite dismutases. This mutation potentially increases the rigidity of the proximal site and might impair the rotation of the reaction intermediate MMD. We found that both wild-type CdChdC and the variant H118A convert coproheme mainly to heme b upon titration with H2O2. Interestingly, the variant A207E mostly accumulates MMD along with small amounts of heme b, whereas H118F is unable to produce heme b and accumulates only MMD. Together with molecular dynamics simulations, the spectroscopic data provide insight into the reaction mechanism and the mode of reorientation of MMD, i.e., a rotation in the active site versus a release and rebinding.
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Affiliation(s)
- Federico Sebastiani
- Dipartimento di Chimica "Ugo Schiff", Università di Firenze, Sesto Fiorentino (FI), Italy
| | - Hanna Michlits
- Department of Chemistry, Institute of Biochemistry, Institute of Molecular Modeling and Simulation, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria
| | - Bettina Lier
- Department of Material Sciences and Process Engineering, Institute of Molecular Modeling and Simulation, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria
| | - Maurizio Becucci
- Dipartimento di Chimica "Ugo Schiff", Università di Firenze, Sesto Fiorentino (FI), Italy
| | - Paul G Furtmüller
- Department of Chemistry, Institute of Biochemistry, Institute of Molecular Modeling and Simulation, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria
| | - Chris Oostenbrink
- Department of Material Sciences and Process Engineering, Institute of Molecular Modeling and Simulation, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria
| | - Christian Obinger
- Department of Chemistry, Institute of Biochemistry, Institute of Molecular Modeling and Simulation, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria
| | - Stefan Hofbauer
- Department of Chemistry, Institute of Biochemistry, Institute of Molecular Modeling and Simulation, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria.
| | - Giulietta Smulevich
- Dipartimento di Chimica "Ugo Schiff", Università di Firenze, Sesto Fiorentino (FI), Italy; INSTM Research Unit of Firenze, Sesto Fiorentino, Italy.
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7
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Tian G, Hao G, Chen X, Liu Y. Tyrosyl Radical-Mediated Sequential Oxidative Decarboxylation of Coproporphyrinogen III through PCET: Theoretical Insights into the Mechanism of Coproheme Decarboxylase ChdC. Inorg Chem 2021; 60:13539-13549. [PMID: 34382397 DOI: 10.1021/acs.inorgchem.1c01864] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The peroxide-dependent coproheme decarboxylase ChdC from Geobacillus stearothermophilus catalyzes two key steps in the synthesis of heme b, i.e., two sequential oxidative decarboxylations of coproporphyrinogen III (coproheme III) at propionate groups P2 and P4. In the binding site of coproheme III, P2 and P4 are anchored by different residues (Tyr144, Arg217, and Ser222 for P2 and Tyr113, Lys148, and Trp156 for P4); however, strong experimental evidence supports that the generated Tyr144 radical acts as an unique intermediary for hydrogen atom transfer (HAT) from both reactive propionates. So far, the reaction details are still unclear. Herein, we carried out quantum mechanics/molecular mechanics calculations to explore the decarboxylation mechanism of coproheme III. In our calculations, the coproheme Cpd I, Fe(IV) = O coupled to a porphyrin radical cation (por•+) with four propionate groups, was used as a reactant model. Our calculations reveal that Tyr144 is directly involved in the decarboxylation of propionate group P2. First, the proton-coupled electron transfer (PCET) occurs from Tyr144 to P2, generating a Tyr144 radical, which then abstracts a hydrogen atom from the Cβ of P2. The β-H extraction was calculated to be the rate-limiting step of decarboxylation. It is the porphyrin radical cation (por•+) that makes the PCET from Tyr144 to P2 to be quite easy to initiate the decarboxylation. Finally, the electron transfers from the Cβ• through the porphyrin to the iron center, leading to the decarboxylation of P2. Importantly, the decarboxylation of P4 mediated by Lys148 was calculated to be very difficult, which suggests that after the P2 decarboxylation, the generated harderoheme III intermediate should rebind or rotate in the active site so that the propionate P4 occupies the binding site of P2, and Tyr144 again mediates the decarboxylation of P4. Thus, our calculations support the fact that Tyr144 is responsible for the decarboxylation of both P2 and P4.
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Affiliation(s)
- Ge Tian
- School of Life Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, Shandong 271000, China.,School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
| | - Gangping Hao
- School of Life Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, Shandong 271000, China
| | - Xiaohua Chen
- National-Municipal Joint Engineering Laboratory for Chemical Process Intensification and Reaction, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China
| | - Yongjun Liu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
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8
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Geeraerts Z, Heskin AK, DuBois J, Rodgers KR, Lukat-Rodgers GS. Structure and reactivity of chlorite dismutase nitrosyls. J Inorg Biochem 2020; 211:111203. [PMID: 32768737 PMCID: PMC7749827 DOI: 10.1016/j.jinorgbio.2020.111203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 07/14/2020] [Accepted: 07/16/2020] [Indexed: 11/28/2022]
Abstract
Ferric nitrosyl ({FeNO}6) and ferrous nitrosyl ({FeNO}7) complexes of the chlorite dismutases (Cld) from Klebsiella pneumoniae and Dechloromonas aromatica have been characterized using UV-visible absorbance and Soret-excited resonance Raman spectroscopy. Both of these Clds form kinetically stable {FeNO}6 complexes and they occupy a unique region of ν(Fe-NO)/ν(N-O) correlation space for proximal histidine liganded heme proteins, characteristic of weak Fe-NO and N-O bonds. This location is attributed to admixed FeIII-NO character of the {FeNO}6 ground state. Cld {FeNO}6 complexes undergo slow reductive nitrosylation to yield {FeNO}7 complexes. The effects of proximal and distal environment on reductive nitroylsation rates for these dimeric and pentameric Clds are reported. The ν(Fe-NO) and ν(N-O) frequencies for Cld {FeNO}7 complexes reveal both six-coordinate (6c) and five-coordinate (5c) nitrosyl hemes. These 6c and 5c forms are in a pH dependent equilibrium. The 6c and 5c {FeNO}7 Cld frequencies provided positions of both Clds on their respective ν(Fe-NO) vs ν(N-O) correlation lines. The 6c {FeNO}7 complexes fall below (along the ν(Fe-NO) axis) the correlation line that reports hydrogen-bond donation to NNO, which is consistent with a relatively weak Fe-NO bond. Kinetic and spectroscopic evidence is consistent with the 5c {FeNO}7 Clds having NO coordinated on the proximal side of the heme, analogous to 5c {FeNO}7 hemes in proteins known to have NO sensing functions.
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Affiliation(s)
- Zachary Geeraerts
- North Dakota State University, Fargo, ND 58108, United States of America
| | - Alisa K Heskin
- North Dakota State University, Fargo, ND 58108, United States of America
| | - Jennifer DuBois
- Montana State University, Bozeman, MT 59717, United States of America
| | - Kenton R Rodgers
- North Dakota State University, Fargo, ND 58108, United States of America.
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9
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Layer G. Heme biosynthesis in prokaryotes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1868:118861. [PMID: 32976912 DOI: 10.1016/j.bbamcr.2020.118861] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/21/2022]
Abstract
The cyclic tetrapyrrole heme is used as a prosthetic group in a broad variety of different proteins in almost all organisms. Often, it is essential for vital biochemical processes such as aerobic and anaerobic respiration as well as photosynthesis. In Nature, heme is made from the common tetrapyrrole precursor 5-aminolevulinic acid, and for a long time it was assumed that heme is biosynthesized by a single, common pathway in all organisms. However, although this is indeed the case in eukaryotes, heme biosynthesis is more diverse in the prokaryotic world, where two additional pathways exist. The final elucidation of the two 'alternative' heme biosynthesis routes operating in some bacteria and archaea was achieved within the last decade. This review summarizes the three different heme biosynthesis pathways with a special emphasis on the two 'new' prokaryotic routes.
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Affiliation(s)
- Gunhild Layer
- Albert-Ludwigs-Universität Freiburg, Institut für Pharmazeutische Wissenschaften, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany.
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10
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Understanding molecular enzymology of porphyrin-binding α + β barrel proteins - One fold, multiple functions. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1869:140536. [PMID: 32891739 PMCID: PMC7611857 DOI: 10.1016/j.bbapap.2020.140536] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/26/2020] [Accepted: 09/02/2020] [Indexed: 11/24/2022]
Abstract
There is a high functional diversity within the structural superfamily of porphyrin-binding dimeric α + β barrel proteins. In this review we aim to analyze structural constraints of chlorite dismutases, dye-decolorizing peroxidases and coproheme decarboxylases in detail. We identify regions of structural variations within the highly conserved fold, which are most likely crucial for functional specificities. The loop linking the two ferredoxin-like domains within one subunit can be of different sequence lengths and can adopt various structural conformations, consequently defining the shape of the substrate channels and the respective active site architectures. The redox cofactor, heme b or coproheme, is oriented differently in either of the analyzed enzymes. By thoroughly dissecting available structures and discussing all available results in the context of the respective functional mechanisms of each of these redox-active enzymes, we highlight unsolved mechanistic questions in order to spark future research in this field.
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11
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Hofbauer S, Helm J, Obinger C, Djinović-Carugo K, Furtmüller PG. Crystal structures and calorimetry reveal catalytically relevant binding mode of coproporphyrin and coproheme in coproporphyrin ferrochelatase. FEBS J 2020; 287:2779-2796. [PMID: 31794133 PMCID: PMC7340540 DOI: 10.1111/febs.15164] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 11/18/2019] [Accepted: 12/02/2019] [Indexed: 01/24/2023]
Abstract
Coproporphyrin ferrochelatases (CpfCs, EC 4.99.1.9) insert ferrous iron into coproporphyrin III yielding coproheme. CpfCs are utilized by prokaryotic, mainly monoderm (Gram-positive) bacteria within the recently detected coproporphyrin-dependent (CPD) heme biosynthesis pathway. Here, we present a comprehensive study on CpfC from Listeria monocytogenes (LmCpfC) including the first crystal structure of a coproheme-bound CpfC. Comparison of crystal structures of apo-LmCpfC and coproheme-LmCpfC allowed identification of structural rearrangements and of amino acids involved in tetrapyrrole macrocycle and Fe2+ binding. Differential scanning calorimetry of apo-, coproporphyrin III-, and coproheme-LmCpfC underline the pronounced noncovalent interaction of both coproporphyrin and coproheme with the protein (ΔTm = 11 °C compared to apo-LmCpfC), which includes the propionates (p2, p4, p6, p7) and the amino acids Arg29, Arg45, Tyr46, Ser53, and Tyr124. Furthermore, the thermodynamics and kinetics of coproporphyrin III and coproheme binding to apo-LmCpfC is presented as well as the kinetics of insertion of ferrous iron into coproporphyrin III-LmCpfC that immediately leads to formation of ferric coproheme-LmCpfC (kcat /KM = 4.7 × 105 m-1 ·s-1 ). We compare the crystal structure of coproheme-LmCpfC with available structures of CpfCs with artificial tetrapyrrole macrocycles and discuss our data on substrate binding, iron insertion and substrate release in the context of the CPD heme biosynthesis pathway. ENZYME: EC 4.99.1.9 DATABASE: pdb-codes of structural data in this work: 6RWV, 6SV3.
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Affiliation(s)
- Stefan Hofbauer
- Department of Chemistry, Institute of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
| | - Johannes Helm
- Department of Chemistry, Institute of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
| | - Christian Obinger
- Department of Chemistry, Institute of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
| | - Kristina Djinović-Carugo
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Austria
- Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia
| | - Paul G Furtmüller
- Department of Chemistry, Institute of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
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12
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Michlits H, Lier B, Pfanzagl V, Djinović-Carugo K, Furtmüller PG, Oostenbrink C, Obinger C, Hofbauer S. Actinobacterial Coproheme Decarboxylases Use Histidine as a Distal Base to Promote Compound I Formation. ACS Catal 2020; 10:5405-5418. [PMID: 32440366 PMCID: PMC7235987 DOI: 10.1021/acscatal.0c00411] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/08/2020] [Indexed: 11/29/2022]
Abstract
![]()
Coproheme
decarboxylases (ChdCs) catalyze the final step in heme b biosynthesis of monoderm and some diderm bacteria. In
this reaction, coproheme is converted to heme b via
monovinyl monopropionate deuteroheme (MMD) in two consecutive decarboxylation
steps. In Firmicutes decarboxylation of propionates 2 and 4 of coproheme
depend on hydrogen peroxide and the presence of a catalytic tyrosine.
Here we demonstrate that ChdCs from Actinobacteria are unique in using
a histidine (H118 in ChdC from Corynebacterium diphtheriae, CdChdC) as a distal base in addition to the redox-active
tyrosine (Y135). We present the X-ray crystal structures of coproheme-CdChdC and MMD-CdChdC, which clearly show
(i) differences in the active site architecture between Firmicutes
and Actinobacteria and (ii) rotation of the redox-active reaction
intermediate (MMD) after formation of the vinyl group at position
2. Distal H118 is shown to catalyze the heterolytic cleavage of hydrogen
peroxide (kapp = (4.90 ± 1.25) ×
104 M–1 s–1). The resulting
Compound I is rapidly converted to a catalytically active Compound
I* (oxoiron(IV) Y135•) that initiates the radical
decarboxylation reactions. As a consequence of the more efficient
Compound I formation, actinobacterial ChdCs exhibit a higher catalytic
efficiency in comparison to representatives from Firmicutes. On the
basis of the kinetic data of wild-type CdChdC and
the variants H118A, Y135A, and H118A/Y135A together with high-resolution
crystal structures and molecular dynamics simulations, we present
a molecular mechanism for the hydrogen peroxide dependent conversion
of coproheme via MMD to heme b and discuss differences
between ChdCs from Actinobacteria and Firmicutes.
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Affiliation(s)
- Hanna Michlits
- Department of Chemistry, Institute of Biochemistry, BOKU−University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Bettina Lier
- Department of Material Sciences and Process Engineering, Institute of Molecular Modeling and Simulation, BOKU−University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Vera Pfanzagl
- Department of Chemistry, Institute of Biochemistry, BOKU−University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Kristina Djinović-Carugo
- Department for Structural and Computational Biology, Max Perutz Laboratories, University of Vienna, A-1030 Vienna, Austria
- Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Paul G. Furtmüller
- Department of Chemistry, Institute of Biochemistry, BOKU−University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Chris Oostenbrink
- Department of Material Sciences and Process Engineering, Institute of Molecular Modeling and Simulation, BOKU−University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Christian Obinger
- Department of Chemistry, Institute of Biochemistry, BOKU−University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Stefan Hofbauer
- Department of Chemistry, Institute of Biochemistry, BOKU−University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
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13
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Zhang Y, Wang J, Yuan C, Liu W, Tan H, Li X, Chen G. Ruffling drives coproheme decarboxylation by facilitating PCET: a theoretical investigation of ChdC. Phys Chem Chem Phys 2020; 22:16117-16124. [DOI: 10.1039/d0cp02690e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Coproheme decarboxylase (ChdC) is an essential enzyme in the coproporphyrin-dependent heme synthesis pathway, which catalyzes oxidative decarboxylation of coproheme at the positions p2 and p4 to generate heme b under the action of hydrogen peroxide.
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Affiliation(s)
- Ying Zhang
- Key Laboratory of Theoretical and Computational Photochemistry
- College of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Junkai Wang
- Key Laboratory of Theoretical and Computational Photochemistry
- College of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Chang Yuan
- Key Laboratory of Theoretical and Computational Photochemistry
- College of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Wei Liu
- Key Laboratory of Theoretical and Computational Photochemistry
- College of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Hongwei Tan
- Key Laboratory of Theoretical and Computational Photochemistry
- College of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Xichen Li
- Key Laboratory of Theoretical and Computational Photochemistry
- College of Chemistry
- Beijing Normal University
- Beijing 100875
- China
| | - Guangju Chen
- Key Laboratory of Theoretical and Computational Photochemistry
- College of Chemistry
- Beijing Normal University
- Beijing 100875
- China
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14
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Milazzo L, Gabler T, Pühringer D, Jandova Z, Maresch D, Michlits H, Pfanzagl V, Djinović-Carugo K, Oostenbrink C, Furtmüller PG, Obinger C, Smulevich G, Hofbauer S. Redox Cofactor Rotates during Its Stepwise Decarboxylation: Molecular Mechanism of Conversion of Coproheme to Heme b. ACS Catal 2019; 9:6766-6782. [PMID: 31423350 PMCID: PMC6691569 DOI: 10.1021/acscatal.9b00963] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 05/20/2019] [Indexed: 12/24/2022]
Abstract
Coproheme decarboxylase (ChdC) catalyzes the last step in the heme biosynthesis pathway of monoderm bacteria with coproheme acting both as redox cofactor and substrate. Hydrogen peroxide mediates the stepwise decarboxylation of propionates 2 and 4 of coproheme. Here we present the crystal structures of coproheme-loaded ChdC from Listeria monocytogenes (LmChdC) and the three-propionate intermediate, for which the propionate at position 2 (p2) has been converted to a vinyl group and is rotated by 90° compared to the coproheme complex structure. Single, double, and triple mutants of LmChdC, in which H-bonding interactions to propionates 2, 4, 6, and 7 were eliminated, allowed us to obtain the assignment of the coproheme propionates by resonance Raman spectroscopy and to follow the H2O2-mediated conversion of coproheme to heme b. Substitution of H2O2 by chlorite allowed us to monitor compound I formation in the inactive Y147H variant which lacks the catalytically essential Y147. This residue was demonstrated to be oxidized during turnover by using the spin-trap 2-methyl-2-nitrosopropane. Based on these findings and the data derived from molecular dynamics simulations of cofactor structures in distinct poses, we propose a reaction mechanism for the stepwise decarboxylation of coproheme that includes a 90° rotation of the intermediate three-propionate redox cofactor.
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Affiliation(s)
- Lisa Milazzo
- Dipartimento
di Chimica “Ugo Schiff”, Università
di Firenze, Via della
Lastruccia 3-13, I-50019 Sesto Fiorentino (FI), Italy
| | - Thomas Gabler
- Department
of Chemistry, Division of Biochemistry, BOKU−University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Dominic Pühringer
- Department
for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, A-1030 Vienna, Austria
| | - Zuzana Jandova
- Department
of Material Sciences and Process Engineering, Institute of Molecular
Modeling and Simulation, BOKU−University
of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Daniel Maresch
- Department
of Chemistry, Division of Biochemistry, BOKU−University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Hanna Michlits
- Department
of Chemistry, Division of Biochemistry, BOKU−University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Vera Pfanzagl
- Department
of Chemistry, Division of Biochemistry, BOKU−University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Kristina Djinović-Carugo
- Department
for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, A-1030 Vienna, Austria
- Department
of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Chris Oostenbrink
- Department
of Material Sciences and Process Engineering, Institute of Molecular
Modeling and Simulation, BOKU−University
of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Paul G. Furtmüller
- Department
of Chemistry, Division of Biochemistry, BOKU−University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Christian Obinger
- Department
of Chemistry, Division of Biochemistry, BOKU−University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Giulietta Smulevich
- Dipartimento
di Chimica “Ugo Schiff”, Università
di Firenze, Via della
Lastruccia 3-13, I-50019 Sesto Fiorentino (FI), Italy
| | - Stefan Hofbauer
- Department
of Chemistry, Division of Biochemistry, BOKU−University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
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