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Gabler T, Dali A, Bellei M, Sebastiani F, Becucci M, Battistuzzi G, Furtmüller PG, Smulevich G, Hofbauer S. Revisiting catalytic His and Glu residues in coproporphyrin ferrochelatase - unexpected activities of active site variants. FEBS J 2024. [PMID: 38390750 DOI: 10.1111/febs.17101] [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: 12/13/2023] [Revised: 01/17/2024] [Accepted: 02/13/2024] [Indexed: 02/24/2024]
Abstract
The identification of the coproporphyrin-dependent heme biosynthetic pathway, which is used almost exclusively by monoderm bacteria in 2015 by Dailey et al. triggered studies aimed at investigating the enzymes involved in this pathway that were originally assigned to the protoporphyrin-dependent heme biosynthetic pathway. Here, we revisit the active site of coproporphyrin ferrochelatase by a biophysical and biochemical investigation using the physiological substrate coproporphyrin III, which in contrast to the previously used substrate protoporphyrin IX has four propionate substituents and no vinyl groups. In particular, we have compared the reactivity of wild-type coproporphyrin ferrochelatase from the firmicute Listeria monocytogenes with those of variants, namely, His182Ala (H182A) and Glu263Gln (E263Q), involving two key active site residues. Interestingly, both variants are active only toward the physiological substrate coproporphyrin III but inactive toward protoporphyrin IX. In addition, E263 exchange impairs the final oxidation step from ferrous coproheme to ferric coproheme. The characteristics of the active site in the context of the residues involved and the substrate binding properties are discussed here using structural and functional means, providing a further contribution to the deciphering of this enigmatic reaction mechanism.
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Affiliation(s)
- Thomas Gabler
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Andrea Dali
- Department of Chemistry "Ugo Schiff" (DICUS), University of Florence, Sesto Fiorentino, Italy
| | - Marzia Bellei
- Department of Life Sciences, University of Modena and Reggio Emilia, Italy
| | - Federico Sebastiani
- Department of Chemistry "Ugo Schiff" (DICUS), University of Florence, Sesto Fiorentino, Italy
| | - Maurizio Becucci
- Department of Chemistry "Ugo Schiff" (DICUS), University of Florence, Sesto Fiorentino, Italy
| | - Gianantonio Battistuzzi
- Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Paul Georg Furtmüller
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Giulietta Smulevich
- Department of Chemistry "Ugo Schiff" (DICUS), University of Florence, Sesto Fiorentino, Italy
- INSTM Research Unit of Firenze, Sesto Fiorentino, Italy
| | - Stefan Hofbauer
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
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2
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Sebastiani F, Dali A, Alonso de Armiño DJ, Campagni L, Patil G, Becucci M, Hofbauer S, Estrin DA, Smulevich G. The role of the distal cavity in carbon monoxide stabilization in the coproheme decarboxylase enzyme from C. diphtheriae. J Inorg Biochem 2023; 245:112243. [PMID: 37196412 DOI: 10.1016/j.jinorgbio.2023.112243] [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: 03/03/2023] [Revised: 04/28/2023] [Accepted: 05/01/2023] [Indexed: 05/19/2023]
Abstract
This work focuses on the carbon monoxide adducts of the wild-type and selected variants of the coproheme decarboxylase from actinobacterial Corynebacterium diphtheriae complexed with coproheme, monovinyl monopropionyl deuteroheme (MMD), and heme b. The UV - vis and resonance Raman spectroscopies together with the molecular dynamics simulations clearly show that the wild-type coproheme-CO adduct is characterized by two CO conformers, one hydrogen-bonded to the distal H118 residue and the other showing a weak polar interaction with the distal cavity. Instead, upon conversion to heme b, i.e. after decarboxylation of propionates 2 and 4 and rotation by 90o of the porphyrin ring inside the cavity, CO probes a less polar environment. In the absence of the H118 residue, both coproheme and heme b complexes form only the non-H-bonded CO species. The unrotated MMD-CO adduct as observed in the H118F variant, confirms that decarboxylation of propionate 2 only, does not affect the heme cavity. The rupture of both the H-bonds involving propionates 2 and 4 destabilizes the porphyrin inside the cavity with the subsequent formation of a CO adduct in an open conformation. In addition, in this work we present data on CO binding to reversed heme b, obtained by hemin reconstitution of the H118A variant, and to heme d, obtained by addition of an excess of hydrogen peroxide. The results will be discussed and compared with those reported for the representatives of the firmicute clade.
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Affiliation(s)
- Federico Sebastiani
- Dipartimento di Chimica "Ugo Schiff" DICUS, Università di Firenze, Via della Lastruccia 3-13, Sesto Fiorentino (FI) I-50019, Italy
| | - Andrea Dali
- Dipartimento di Chimica "Ugo Schiff" DICUS, Università di Firenze, Via della Lastruccia 3-13, Sesto Fiorentino (FI) I-50019, Italy
| | - Diego Javier Alonso de Armiño
- CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina
| | - Lorenzo Campagni
- Dipartimento di Chimica "Ugo Schiff" DICUS, Università di Firenze, Via della Lastruccia 3-13, Sesto Fiorentino (FI) I-50019, Italy
| | - Gaurav Patil
- University of Natural Resources and Life Sciences, Department of Chemistry, Institute of Biochemistry, Muthgasse 18, Vienna A-1190, Austria
| | - Maurizio Becucci
- Dipartimento di Chimica "Ugo Schiff" DICUS, Università di Firenze, Via della Lastruccia 3-13, Sesto Fiorentino (FI) I-50019, Italy.
| | - Stefan Hofbauer
- University of Natural Resources and Life Sciences, Department of Chemistry, Institute of Biochemistry, Muthgasse 18, Vienna A-1190, Austria.
| | - Dario A Estrin
- CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina; Universidad de Buenos Aires, Departamento de Quimica Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Buenos Aires C1428EGA, Argentina.
| | - Giulietta Smulevich
- Dipartimento di Chimica "Ugo Schiff" DICUS, Università di Firenze, Via della Lastruccia 3-13, Sesto Fiorentino (FI) I-50019, Italy; INSTM Research Unit of Firenze, via della Lastruccia 3, Sesto Fiorentino I-50019, Italy.
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3
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Falb N, Patil G, Furtmüller PG, Gabler T, Hofbauer S. Structural aspects of enzymes involved in prokaryotic Gram-positive heme biosynthesis. Comput Struct Biotechnol J 2023; 21:3933-3945. [PMID: 37593721 PMCID: PMC10427985 DOI: 10.1016/j.csbj.2023.07.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/19/2023] [Accepted: 07/19/2023] [Indexed: 08/19/2023] Open
Abstract
The coproporphyrin dependent heme biosynthesis pathway is almost exclusively utilized by Gram-positive bacteria. This fact makes it a worthwhile topic for basic research, since a fundamental understanding of a metabolic pathway is necessary to translate the focus towards medical biotechnology, which is very relevant in this specific case, considering the need for new antibiotic targets to counteract the pathogenicity of Gram-positive superbugs. Over the years a lot of structural data on the set of enzymes acting in Gram-positive heme biosynthesis has accumulated in the Protein Database (www.pdb.org). One major challenge is to filter and analyze all available structural information in sufficient detail in order to be helpful and to draw conclusions. Here we pursued to give a holistic overview of structural information on enzymes involved in the coproporphyrin dependent heme biosynthesis pathway. There are many aspects to be extracted from experimentally determined structures regarding the reaction mechanisms, where the smallest variation of the position of an amino acid residue might be important, but also on a larger level regarding protein-protein interactions, where the focus has to be on surface characteristics and subunit (secondary) structural elements and oligomerization. This review delivers a status quo, highlights still missing information, and formulates future research endeavors in order to better understand prokaryotic heme biosynthesis.
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Affiliation(s)
- Nikolaus Falb
- University of Natural Resources and Life Sciences, Vienna, Department of Chemistry, Institute of Biochemistry, Muthgasse 18, A-1190 Vienna, Austria
| | - Gaurav Patil
- University of Natural Resources and Life Sciences, Vienna, Department of Chemistry, Institute of Biochemistry, Muthgasse 18, A-1190 Vienna, Austria
| | - Paul G. Furtmüller
- University of Natural Resources and Life Sciences, Vienna, Department of Chemistry, Institute of Biochemistry, Muthgasse 18, A-1190 Vienna, Austria
| | - Thomas Gabler
- University of Natural Resources and Life Sciences, Vienna, Department of Chemistry, Institute of Biochemistry, Muthgasse 18, A-1190 Vienna, Austria
| | - Stefan Hofbauer
- University of Natural Resources and Life Sciences, Vienna, Department of Chemistry, Institute of Biochemistry, Muthgasse 18, A-1190 Vienna, Austria
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4
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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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Ushimaru R, Lyu J, Abe I. Diverse enzymatic chemistry for propionate side chain cleavages in tetrapyrrole biosynthesis. J Ind Microbiol Biotechnol 2023; 50:kuad016. [PMID: 37422437 PMCID: PMC10548856 DOI: 10.1093/jimb/kuad016] [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: 05/03/2023] [Accepted: 07/07/2023] [Indexed: 07/10/2023]
Abstract
Tetrapyrroles represent a unique class of natural products that possess diverse chemical architectures and exhibit a broad range of biological functions. Accordingly, they attract keen attention from the natural product community. Many metal-chelating tetrapyrroles serve as enzyme cofactors essential for life, while certain organisms produce metal-free porphyrin metabolites with biological activities potentially beneficial for the producing organisms and for human use. The unique properties of tetrapyrrole natural products derive from their extensively modified and highly conjugated macrocyclic core structures. Most of these various tetrapyrrole natural products biosynthetically originate from a branching point precursor, uroporphyrinogen III, which contains propionate and acetate side chains on its macrocycle. Over the past few decades, many modification enzymes with unique catalytic activities, and the diverse enzymatic chemistries employed to cleave the propionate side chains from the macrocycles, have been identified. In this review, we highlight the tetrapyrrole biosynthetic enzymes required for the propionate side chain removal processes and discuss their various chemical mechanisms. ONE-SENTENCE SUMMARY This mini-review describes various enzymes involved in the propionate side chain cleavages during the biosynthesis of tetrapyrrole cofactors and secondary metabolites.
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Affiliation(s)
- Richiro Ushimaru
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Jiaqi Lyu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Ikuro Abe
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
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6
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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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Abstract
Heme (protoheme IX) is an essential cofactor for a large variety of proteins whose functions vary from one electron reactions to binding gases. While not ubiquitous, heme is found in the great majority of known life forms. Unlike most cofactors that are acquired from dietary sources, the vast majority of organisms that utilize heme possess a complete pathway to synthesize the compound. Indeed, dietary heme is most frequently utilized as an iron source and not as a source of heme. In Nature there are now known to exist three pathways to synthesize heme. These are the siroheme dependent (SHD) pathway which is the most ancient, but least common of the three; the coproporphyrin dependent (CPD) pathway which with one known exception is found only in gram positive bacteria; and the protoporphyrin dependent (PPD) pathway which is found in gram negative bacteria and all eukaryotes. All three pathways share a core set of enzymes to convert the first committed intermediate, 5-aminolevulinate (ALA) into uroporphyrinogen III. In the current review all three pathways are reviewed as well as the two known pathways to synthesize ALA. In addition, interesting features of some heme biosynthesis enzymes are discussed as are the regulation and disorders of heme biosynthesis.
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Affiliation(s)
- Harry A Dailey
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602-1111, USA
- Department of Microbiology, University of Georgia, Athens, GA 30602-1111, USA
| | - Amy E Medlock
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602-1111, USA
- Augusta University/University of Georgia Medical Partnership, University of Georgia, Athens, GA, USA
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8
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An active site at work – the role of key residues in C. diphteriae coproheme decarboxylase. J Inorg Biochem 2022; 229:111718. [DOI: 10.1016/j.jinorgbio.2022.111718] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/14/2021] [Accepted: 01/01/2022] [Indexed: 12/12/2022]
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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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Michlits H, Valente N, Mlynek G, Hofbauer S. Initial Steps to Engineer Coproheme Decarboxylase to Obtain Stereospecific Monovinyl, Monopropionyl Deuterohemes. Front Bioeng Biotechnol 2022; 9:807678. [PMID: 35141216 PMCID: PMC8819088 DOI: 10.3389/fbioe.2021.807678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 12/29/2021] [Indexed: 11/13/2022] Open
Abstract
The oxidative decarboxylation of coproheme to form heme b by coproheme decarboxylase is a stereospecific two-step reaction. In the first step, the propionate at position two (p2) is cleaved off the pyrrole ring A to form a vinyl group at this position. Subsequently, the propionate at position four (p4) on pyrrole ring B is cleaved off and heme b is formed. In this study, we attempted to engineer coproheme decarboxylase from Corynebacterium diphtheriae to alter the stereospecificity of this reaction. By introducing a tyrosine residue in proximity to the propionate at position 4, we were able to create a new radical center in the active site. However, the artificial Tyr183• radical could not be shown to catalyze any decarboxylation.
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Affiliation(s)
- Hanna Michlits
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Nina Valente
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Georg Mlynek
- Core Facility Biomolecular and Cellular Analysis, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Stefan Hofbauer
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
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11
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Gabler T, Sebastiani F, Helm J, Dali A, Obinger C, Furtmüller PG, Smulevich G, Hofbauer S. Substrate specificity and complex stability of coproporphyrin ferrochelatase is governed by hydrogen-bonding interactions of the four propionate groups. FEBS J 2021; 289:1680-1699. [PMID: 34719106 DOI: 10.1111/febs.16257] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/19/2021] [Accepted: 10/28/2021] [Indexed: 11/24/2022]
Abstract
Coproporpyhrin III is the substrate of coproporphyrin ferrochelatases (CpfCs). These enzymes catalyse the insertion of ferrous iron into the porphyrin ring. This is the penultimate step within the coproporphyrin-dependent haeme biosynthesis pathway. This pathway was discovered in 2015 and is mainly utilised by monoderm bacteria. Prior to this discovery, monoderm bacteria were believed to utilise the protoporphyrin-dependent pathway, analogously to diderm bacteria, where the substrate for the respective ferrochelatase is protoporphyrin IX, which has two propionate groups at positions 6 and 7 and two vinyl groups at positions 2 and 4. In this work, we describe for the first time the interactions of the four-propionate substrate, coproporphyrin III, and the four-propionate product, iron coproporphyrin III (coproheme), with the CpfC from Listeria monocytogenes and pin down differences with respect to the protoporphyrin IX and haeme b complexes in the wild-type (WT) enzyme. We further created seven LmCpfC variants aiming at altering substrate and product coordination. The WT enzyme and all the variants were comparatively studied by spectroscopic, thermodynamic and kinetic means to investigate in detail the H-bonding interactions, which govern complex stability and substrate specificity. We identified a tyrosine residue (Y124 in LmCpfC), coordinating the propionate at position 2, which is conserved in monoderm CpfCs, to be highly important for binding and stabilisation. Importantly, we also describe a tyrosine-serine-threonine triad, which coordinates the propionate at position 4. The study of the triad variants indicates structural differences between the coproporphyrin III and the coproheme complexes. ENZYME: EC 4.99.1.9.
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Affiliation(s)
- Thomas Gabler
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Federico Sebastiani
- Dipartimento di Chimica 'Ugo Schiff' (DICUS), Università di Firenze, Sesto Fiorentino, Italy
| | - Johannes Helm
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Andrea Dali
- Dipartimento di Chimica 'Ugo Schiff' (DICUS), Università di Firenze, Sesto Fiorentino, Italy
| | - Christian Obinger
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Paul G Furtmüller
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Giulietta Smulevich
- Dipartimento di Chimica 'Ugo Schiff' (DICUS), Università di Firenze, Sesto Fiorentino, Italy.,INSTM Research Unit of Firenze, Sesto Fiorentino, Italy
| | - Stefan Hofbauer
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
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12
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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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13
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Sheng X, Himo F. Mechanisms of metal-dependent non-redox decarboxylases from quantum chemical calculations. Comput Struct Biotechnol J 2021; 19:3176-3186. [PMID: 34141138 PMCID: PMC8187880 DOI: 10.1016/j.csbj.2021.05.044] [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: 03/11/2021] [Revised: 05/24/2021] [Accepted: 05/24/2021] [Indexed: 11/18/2022] Open
Abstract
Quantum chemical calculations are today an extremely valuable tool for studying enzymatic reaction mechanisms. In this mini-review, we summarize our recent work on several metal-dependent decarboxylases, where we used the so-called cluster approach to decipher the details of the reaction mechanisms, including elucidation of the identity of the metal cofactors and the origins of substrate specificity. Decarboxylases are of growing potential for biocatalytic applications, as they can be used in the synthesis of novel compounds of, e.g., pharmaceutical interest. They can also be employed in the reverse direction, providing a strategy to synthesize value‐added chemicals by CO2 fixation. A number of non-redox metal-dependent decarboxylases from the amidohydrolase superfamily have been demonstrated to have promiscuous carboxylation activities and have attracted great attention in the recent years. The computational mechanistic studies provide insights that are important for the further modification and utilization of these enzymes in industrial processes. The discussed enzymes are: 5‐carboxyvanillate decarboxylase, γ‐resorcylate decarboxylase, 2,3‐dihydroxybenzoic acid decarboxylase, and iso-orotate decarboxylase.
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Key Words
- 2,3-DHBD, 2,3‐dihydroxybenzoic acid decarboxylase
- 2,6-DHBD, 2,6‐dihydroxybenzoic acid decarboxylase
- 2-NR, 2-nitroresorcinol
- 5-CV, 5-carboxyvanillate
- 5-NV, 5-nitrovanillate
- 5caU, 5-carboxyuracil
- AHS, amidohydrolase superfamily
- Biocatalysis
- Decarboxylase
- Density functional theory
- IDCase, iso-orotate decarboxylase
- LigW, 5‐carboxyvanillate decarboxylase
- MIMS, membrane inlet mass spectrometry
- QM/MM, quantum mechanics/molecular mechanics
- Reaction mechanism
- Transition state
- γ-RS, γ-resorcylate
- γ-RSD, γ‐resorcylate decarboxylase
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Affiliation(s)
- Xiang Sheng
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, and National Technology Innovation Center for Synthetic Biology, Tianjin 300308, PR China
| | - Fahmi Himo
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-10691 Stockholm, Sweden
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14
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Möller J, Nosratabadi F, Musella L, Hofmann J, Burkovski A. Corynebacterium diphtheriae Proteome Adaptation to Cell Culture Medium and Serum. Proteomes 2021; 9:proteomes9010014. [PMID: 33805816 PMCID: PMC8005964 DOI: 10.3390/proteomes9010014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 12/03/2022] Open
Abstract
Host-pathogen interactions are often studied in vitro using primary or immortal cell lines. This set-up avoids ethical problems of animal testing and has the additional advantage of lower costs. However, the influence of cell culture media on bacterial growth and metabolism is not considered or investigated in most cases. To address this question growth and proteome adaptation of Corynebacterium diphtheriae strain ISS3319 were investigated in this study. Bacteria were cultured in standard growth medium, cell culture medium, and fetal calf serum. Mass spectrometric analyses and label-free protein quantification hint at an increased bacterial pathogenicity when grown in cell culture medium as well as an influence of the growth medium on the cell envelope.
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Affiliation(s)
- Jens Möller
- Microbiology Division, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany; (F.N.); (L.M.); (A.B.)
- Correspondence: ; Tel.: +49-9131-85-28802
| | - Fatemeh Nosratabadi
- Microbiology Division, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany; (F.N.); (L.M.); (A.B.)
| | - Luca Musella
- Microbiology Division, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany; (F.N.); (L.M.); (A.B.)
| | - Jörg Hofmann
- Biochemistry Division, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany;
| | - Andreas Burkovski
- Microbiology Division, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany; (F.N.); (L.M.); (A.B.)
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15
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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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16
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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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17
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Möller J, Schorlemmer S, Hofmann J, Burkovski A. Cellular and Extracellular Proteome of the Animal Pathogen Corynebacterium silvaticum, a Close Relative of Zoonotic Corynebacterium ulcerans and Corynebacterium pseudotuberculosis. Proteomes 2020; 8:proteomes8030019. [PMID: 32806579 PMCID: PMC7564913 DOI: 10.3390/proteomes8030019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/03/2020] [Accepted: 08/10/2020] [Indexed: 01/22/2023] Open
Abstract
Corynebacterium silvaticum is a newly described animal pathogen, closely related to the emerging human pathogen Corynebacterium ulcerans and Corynebacterium pseudotuberculosis, a major pathogen of small ruminants. In this study, proteins of a whole cell and a shaving fraction and the exoproteome of C. silvaticum strain W25 were analyzed as a first proteome study of this species. In total, 1305 proteins were identified out of 2013 proteins encoded by the W25 genome sequence and number of putative virulence factors were detected already under standard growth conditions including phospholipase D and sialidase. An up to now uncharacterized trypsin-like protease is by far the most secreted protein in this species, indicating a putative role in pathogenicity. Furthermore, the proteome analyses carried out in this study support the recently published taxonomical delineation of C. silvaticum from the closely related zoonotic Corynebacterium species.
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Affiliation(s)
- Jens Möller
- Microbiology Division, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany; (J.M.); (S.S.)
| | - Svenja Schorlemmer
- Microbiology Division, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany; (J.M.); (S.S.)
| | - Jörg Hofmann
- Biochemistry Division, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany;
| | - Andreas Burkovski
- Microbiology Division, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany; (J.M.); (S.S.)
- Correspondence: ; Tel.: +49-9131-85-28086
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18
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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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19
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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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20
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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] [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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21
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Milazzo L, Gabler T, Pfanzagl V, Michlits H, Furtmüller PG, Obinger C, Hofbauer S, Smulevich G. The hydrogen bonding network of coproheme in coproheme decarboxylase from Listeria monocytogenes: Effect on structure and catalysis. J Inorg Biochem 2019; 195:61-70. [PMID: 30925402 PMCID: PMC6517287 DOI: 10.1016/j.jinorgbio.2019.03.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 02/28/2019] [Accepted: 03/10/2019] [Indexed: 11/29/2022]
Abstract
Coproheme decarboxylase (ChdC) catalyzes the oxidative decarboxylation of coproheme to heme b, i.e. the last step in the recently described coproporphyrin-dependent pathway. Coproheme decarboxylation from Listeria monocytogenes is a robust enzymatic reaction of low catalytic efficiency. Coproheme acts as both substrate and redox cofactor activated by H2O2. It fully depends on the catalytic Y147 close to the propionyl group at position 2. In the present study we have investigated the effect of disruption of the comprehensive and conserved hydrogen bonding network between the four propionates and heme cavity residues on (i) the conformational stability of the heme cavity, (ii) the electronic configuration of the ferric redox cofactor/substrate, (iii) the binding of carbon monoxide and, (iv) the decarboxylation reaction mediated by addition of H2O2. Nine single, double and triple mutants of ChdC from Listeria monocytogenes were produced in E. coli. The respective coproheme- and heme b-complexed proteins were studied by UV–Vis, resonance Raman, circular dichroism spectroscopy, and mass spectrometry. Interactions of propionates 2 and 4 with residues in the hydrophobic cavity are crucial for maintenance of the heme cavity architecture, for the mobile distal glutamine to interact with carbon monoxide, and to keep the heme cavity in a closed conformation during turnover. By contrast, the impact of substitution of residues interacting with solvent exposed propionates 6 and 7 was negligible. Except for Y147A and K151A all mutant ChdCs exhibited a wild-type-like catalytic activity. The findings are discussed with respect to the structure-function relationships of ChdCs.
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Affiliation(s)
- Lisa Milazzo
- Dipartimento di Chimica "Ugo Schiff", Università di Firenze, Via della Lastruccia 3-13, 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
| | - Vera Pfanzagl
- 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
| | - 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
| | - Stefan Hofbauer
- 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, 50019 Sesto Fiorentino, (Fi), Italy.
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22
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Milazzo L, Hofbauer S, Howes BD, Gabler T, Furtmüller PG, Obinger C, Smulevich G. Insights into the Active Site of Coproheme Decarboxylase from Listeria monocytogenes. Biochemistry 2018. [PMID: 29536725 PMCID: PMC5940323 DOI: 10.1021/acs.biochem.8b00186] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Coproheme decarboxylases (ChdC) catalyze the hydrogen peroxide-mediated conversion of coproheme to heme b. This work compares the structure and function of wild-type (WT) coproheme decarboxylase from Listeria monocytogenes and its M149A, Q187A, and M149A/Q187A mutants. The UV-vis, resonance Raman, and electron paramagnetic resonance spectroscopies clearly show that the ferric form of the WT protein is a pentacoordinate quantum mechanically mixed-spin state, which is very unusual in biological systems. Exchange of the Met149 residue to Ala dramatically alters the heme coordination, which becomes a 6-coordinate low spin species with the amide nitrogen atom of the Q187 residue bound to the heme iron. The interaction between M149 and propionyl 2 is found to play an important role in keeping the Q187 residue correctly positioned for closure of the distal cavity. This is confirmed by the observation that in the M149A variant two CO conformers are present corresponding to open (A0) and closed (A1) conformations. The CO of the latter species, the only conformer observed in the WT protein, is H-bonded to Q187. In the absence of the Q187 residue or in the adducts of all the heme b forms of ChdC investigated herein (containing vinyls in positions 2 and 4), only the A0 conformer has been found. Moreover, M149 is shown to be involved in the formation of a covalent bond with a vinyl substituent of heme b at excess of hydrogen peroxide.
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Affiliation(s)
- Lisa Milazzo
- Dipartimento di Chimica "Ugo Schiff" , Università di Firenze , Via della Lastruccia 3-13 , 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
| | - Barry D Howes
- Dipartimento di Chimica "Ugo Schiff" , Università di Firenze , Via della Lastruccia 3-13 , 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
| | - 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 , 50019 Sesto Fiorentino (Fi) , Italy
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