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Balogun O, Nejak-Bowen K. The Hepatic Porphyrias: Revealing the Complexities of a Rare Disease. Semin Liver Dis 2023; 43:446-459. [PMID: 37973028 PMCID: PMC11256094 DOI: 10.1055/s-0043-1776760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
The porphyrias are a group of metabolic disorders that are caused by defects in heme biosynthesis pathway enzymes. The result is accumulation of heme precursors, which can cause neurovisceral and/or cutaneous photosensitivity. Liver is commonly either a source or target of excess porphyrins, and porphyria-associated hepatic dysfunction ranges from minor abnormalities to liver failure. In this review, the first of a three-part series, we describe the defects commonly found in each of the eight enzymes involved in heme biosynthesis. We also discuss the pathophysiology of the hepatic porphyrias in detail, covering epidemiology, histopathology, diagnosis, and complications. Cellular consequences of porphyrin accumulation are discussed, with an emphasis on oxidative stress, protein aggregation, hepatocellular cancer, and endothelial dysfunction. Finally, we review current therapies to treat and manage symptoms of hepatic porphyria.
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Affiliation(s)
- Oluwashanu Balogun
- Department of Experimental Pathology, University of Pittsburgh, Pittsburgh, PA
| | - Kari Nejak-Bowen
- Department of Experimental Pathology, University of Pittsburgh, Pittsburgh, PA
- Pittsburgh Liver Institute, University of Pittsburgh, Pittsburgh, PA
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2
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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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3
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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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4
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Yien YY, Perfetto M. Regulation of Heme Synthesis by Mitochondrial Homeostasis Proteins. Front Cell Dev Biol 2022; 10:895521. [PMID: 35832791 PMCID: PMC9272004 DOI: 10.3389/fcell.2022.895521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 05/12/2022] [Indexed: 11/19/2022] Open
Abstract
Heme plays a central role in diverse, life-essential processes that range from ubiquitous, housekeeping pathways such as respiration, to highly cell-specific ones such as oxygen transport by hemoglobin. The regulation of heme synthesis and its utilization is highly regulated and cell-specific. In this review, we have attempted to describe how the heme synthesis machinery is regulated by mitochondrial homeostasis as a means of coupling heme synthesis to its utilization and to the metabolic requirements of the cell. We have focused on discussing the regulation of mitochondrial heme synthesis enzymes by housekeeping proteins, transport of heme intermediates, and regulation of heme synthesis by macromolecular complex formation and mitochondrial metabolism. Recently discovered mechanisms are discussed in the context of the model organisms in which they were identified, while more established work is discussed in light of technological advancements.
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Cheng J, Liu WQ, Zhu X, Zhang Q. Functional Diversity of HemN-like Proteins. ACS BIO & MED CHEM AU 2022; 2:109-119. [PMID: 37101745 PMCID: PMC10114718 DOI: 10.1021/acsbiomedchemau.1c00058] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
HemN is a radical S-adenosylmethionine (SAM) enzyme that catalyzes the anaerobic oxidative decarboxylation of coproporphyrinogen III to produce protoporphyrinogen IX, a key intermediate in heme biosynthesis. Proteins homologous to HemN (HemN-like proteins) are widespread in both prokaryotes and eukaryotes. Although these proteins are in most cases annotated as anaerobic coproporphyrinogen III oxidases (CPOs) in the public database, many of them are actually not CPOs but have diverse functions such as methyltransferases, cyclopropanases, heme chaperones, to name a few. This Perspective discusses the recent advances in the understanding of HemN-like proteins, and particular focus is placed on the diverse chemistries and functions of this growing protein family.
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Affiliation(s)
- Jinduo Cheng
- Department of Chemistry, Fudan University, Shanghai, 200433, China
| | - Wan-Qiu Liu
- Department of Chemistry, Fudan University, Shanghai, 200433, China
| | - Xiaoyu Zhu
- Department of Chemistry, Fudan University, Shanghai, 200433, China
| | - Qi Zhang
- Department of Chemistry, Fudan University, Shanghai, 200433, China
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6
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A proteome-wide atlas of lysine-reactive chemistry. Nat Chem 2021; 13:1081-1092. [PMID: 34504315 DOI: 10.1038/s41557-021-00765-4] [Citation(s) in RCA: 102] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 07/05/2021] [Indexed: 01/24/2023]
Abstract
Recent advances in chemical proteomics have begun to characterize the reactivity and ligandability of lysines on a global scale. Yet, only a limited diversity of aminophilic electrophiles have been evaluated for interactions with the lysine proteome. Here, we report an in-depth profiling of >30 uncharted aminophilic chemotypes that greatly expands the content of ligandable lysines in human proteins. Aminophilic electrophiles showed disparate proteomic reactivities that range from selective interactions with a handful of lysines to, for a set of dicarboxaldehyde fragments, remarkably broad engagement of the covalent small-molecule-lysine interactions captured by the entire library. We used these latter 'scout' electrophiles to efficiently map ligandable lysines in primary human immune cells under stimulatory conditions. Finally, we show that aminophilic compounds perturb diverse biochemical functions through site-selective modification of lysines in proteins, including protein-RNA interactions implicated in innate immune responses. These findings support the broad potential of covalent chemistry for targeting functional lysines in the human proteome.
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Ma J, Yang S, Wang D, Tang K, Feng XX, Feng XZ. Genetic Mapping of a Light-Dependent Lesion Mimic Mutant Reveals the Function of Coproporphyrinogen III Oxidase Homolog in Soybean. FRONTIERS IN PLANT SCIENCE 2020; 11:557. [PMID: 32457787 PMCID: PMC7227399 DOI: 10.3389/fpls.2020.00557] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 04/14/2020] [Indexed: 05/30/2023]
Abstract
Lesion mimic mutants provide ideal genetic materials for elucidating the molecular mechanism of cell death and disease resistance. Here, we isolated a Glycine max lesion mimic mutant 2-1 (Gmlmm2-1), which displayed a light-dependent cell death phenotype. Map-based cloning revealed that GmLMM2 encods a coproporphyrinogen III oxidase and participates in tetrapyrrole biosynthesis. Knockout of GmLMM2 led to necrotic spots on developing leaves of CRISPR/Cas9 induced mutants. The GmLMM2 defect decreased the chlorophyll content by disrupting tetrapyrrole biosynthesis and enhanced resistance to Phytophthora sojae. These results suggested that GmLMM2 gene played an important role in the biosynthesis of tetrapyrrole and light-dependent defense in soybeans.
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Affiliation(s)
- Jingjing Ma
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Suxin Yang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
| | - Dongmei Wang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Kuanqiang Tang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xing Xing Feng
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xian Zhong Feng
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
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Phillips JD. Heme biosynthesis and the porphyrias. Mol Genet Metab 2019; 128:164-177. [PMID: 31326287 PMCID: PMC7252266 DOI: 10.1016/j.ymgme.2019.04.008] [Citation(s) in RCA: 106] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 04/10/2019] [Accepted: 04/18/2019] [Indexed: 01/08/2023]
Abstract
Porphyrias, is a general term for a group of metabolic diseases that are genetic in nature. In each specific porphyria the activity of specific enzymes in the heme biosynthetic pathway is defective and leads to accumulation of pathway intermediates. Phenotypically, each disease leads to either neurologic and/or photocutaneous symptoms based on the metabolic intermediate that accumulates. In each porphyria the distinct patterns of these substances in plasma, erythrocytes, urine and feces are the basis for diagnostically defining the metabolic defect underlying the clinical observations. Porphyrias may also be classified as either erythropoietic or hepatic, depending on the principal site of accumulation of pathway intermediates. The erythropoietic porphyrias are congenital erythropoietic porphyria (CEP), and erythropoietic protoporphyria (EPP). The acute hepatic porphyrias include ALA dehydratase deficiency porphyria, acute intermittent porphyria (AIP), hereditary coproporphyria (HCP) and variegate porphyria (VP). Porphyria cutanea tarda (PCT) is the only porphyria that has both genetic and/or environmental factors that lead to reduced activity of uroporphyrinogen decarboxylase in the liver. Each of the 8 enzymes in the heme biosynthetic pathway have been associated with a specific porphyria (Table 1). Mutations affecting the erythroid form of ALA synthase (ALAS2) are most commonly associated with X-linked sideroblastic anemia, however, gain-of-function mutations of ALAS2 have also been associated with a variant form of EPP. This overview does not describe the full clinical spectrum of the porphyrias, but is meant to be an overview of the biochemical steps that are required to make heme in both erythroid and non-erythroid cells.
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Affiliation(s)
- John D Phillips
- Division of Hematology, Department of Medicine, University of Utah School of Medicine, Salt Lake City, UT, United States of America.
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9
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Yasuda M, Chen B, Desnick RJ. Recent advances on porphyria genetics: Inheritance, penetrance & molecular heterogeneity, including new modifying/causative genes. Mol Genet Metab 2019; 128:320-331. [PMID: 30594473 PMCID: PMC6542720 DOI: 10.1016/j.ymgme.2018.11.012] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 11/26/2018] [Accepted: 11/26/2018] [Indexed: 12/16/2022]
Abstract
The inborn errors of heme biosynthesis, the Porphyrias, include eight major disorders resulting from loss-of-function (LOF) or gain-of-function (GOF) mutations in eight of the nine heme biosynthetic genes. The major sites of heme biosynthesis are the liver and erythron, and the underlying pathophysiology of each of these disorders depends on the unique biochemistry, cell biology, and genetic mechanisms in these tissues. The porphyrias are classified into three major categories: 1) the acute hepatic porphyrias (AHPs), including Acute Intermittent Porphyria (AIP), Hereditary Coproporphyria (HCP), Variegate Porphyria (VP), and 5-Aminolevlulinic Acid Dehydratase Deficient Porphyria (ADP); 2) a hepatic cutaneous porphyria, Porphyria Cutanea Tarda (PCT); and 3) the cutaneous erythropoietic porphyrias, Congenital Erythropoietic Porphyria (CEP), Erythropoietic Protoporphyria (EPP), and X-Linked Protoporphyria (XLP). Their modes of inheritance include autosomal dominant with markedly decreased penetrance (AIP, VP, and HCP), autosomal recessive (ADP, CEP, and EPP), or X-linked (XLP), as well as an acquired sporadic form (PCT). There are severe homozygous dominant forms of the three AHPs. For each porphyria, its phenotype, inheritance pattern, unique genetic principles, and molecular genetic heterogeneity are presented. To date, >1000 mutations in the heme biosynthetic genes causing their respective porphyrias have been reported, including low expression alleles and genotype/phenotype correlations that predict severity for certain porphyrias. The tissue-specific regulation of heme biosynthesis and the unique genetic mechanisms for each porphyria are highlighted.
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Affiliation(s)
- Makiko Yasuda
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States.
| | - Brenden Chen
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States.
| | - Robert J Desnick
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States.
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Moghe A, Ramanujam V, Phillips J, Desnick R, Anderson K. Harderoporphyria: Case of lifelong photosensitivity associated with compound heterozygous coproporphyrinogen oxidase (CPOX) mutations. Mol Genet Metab Rep 2019; 19:100457. [PMID: 30828546 PMCID: PMC6383327 DOI: 10.1016/j.ymgmr.2019.100457] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 01/26/2019] [Indexed: 11/20/2022] Open
Abstract
A 78-year-old man with a history of neonatal anemia and jaundice and life-long photosensitivity was found to have harderoporphyria, as evidenced by increased porphyrins in urine, plasma, erythrocytes and feces including large amounts of harderoporphyrin in feces and erythrocytes. Two previously undescribed coproporphyrinogen oxidase (CPOX) mutations were identified, including a deletion of four amino acids in a region of the enzyme mutated in 7 of the 8 previously reported cases. This case increases the molecular heterogeneity of this rare porphyria, and illustrates that it should be considered as a cause of chronic photosensitivity and porphyrin elevation at any age.
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Affiliation(s)
- A. Moghe
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX, USA
| | - V.M.S. Ramanujam
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX, USA
| | - J.D. Phillips
- Department of Medicine, University of Utah, Salt Lake City, UT, USA
| | - R.J. Desnick
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mt. Sinai, New York, NY, USA
| | - K.E. Anderson
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX, USA
- Corresponding author at: Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX 77555-1109, USA.
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11
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Revisiting the Mechanism of the Anaerobic Coproporphyrinogen III Oxidase HemN. Angew Chem Int Ed Engl 2019; 58:6235-6238. [DOI: 10.1002/anie.201814708] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 03/13/2019] [Indexed: 12/26/2022]
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12
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Ji X, Mo T, Liu W, Ding W, Deng Z, Zhang Q. Revisiting the Mechanism of the Anaerobic Coproporphyrinogen III Oxidase HemN. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201814708] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Xinjian Ji
- Department of ChemistryFudan University Shanghai 200433 China
| | - Tianlu Mo
- Department of ChemistryFudan University Shanghai 200433 China
| | - Wan‐Qiu Liu
- Department of ChemistryFudan University Shanghai 200433 China
| | - Wei Ding
- State Key Laboratory of Microbial MetabolismSchool of Life Sciences & BiotechnologyShanghai Jiao Tong University Shanghai 200240 China
| | - Zixin Deng
- State Key Laboratory of Microbial MetabolismSchool of Life Sciences & BiotechnologyShanghai Jiao Tong University Shanghai 200240 China
| | - Qi Zhang
- Department of ChemistryFudan University Shanghai 200433 China
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Borrero Corte MJ, Jara Rubio F, Morán Jiménez MJ, Díaz Díaz S, Castelbón Fernandez FJ, García Pastor I, Enríquez de Salamanca R, Méndez M. Molecular analysis of 19 Spanish patients with mixed porphyrias. Eur J Med Genet 2018; 62:103589. [PMID: 30476629 DOI: 10.1016/j.ejmg.2018.11.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 11/12/2018] [Accepted: 11/22/2018] [Indexed: 01/07/2023]
Abstract
Porphyrias are rare diseases caused by alterations in the heme biosynthetic pathway. Depending on the afected enzyme, porphyrin precursors or porphyrins are overproduced, causing acute neurovisceral attacks or dermal photosensitivity, respectively. Hereditary Coproporphyria (HCP) and Variegate Porphyria (VP) are mixed porphyrias since they can present acute and/or cutaneous symptoms. These diseases are caused by a deficiency of coproporphyrinogen oxidase (CPOX) in HCP, and protoporphyrinogen oxidase (PPOX) in VP. Herein, we studied nineteen unrelated Spanish patients with mixed porphyrias. The diagnosis of either, HCP or VP was made on the basis of clinical symptoms, biochemical findings and the identification of the mutation responsible in the CPOX or PPOX genes. Two patients presented both acute and cutaneous symptoms. In most patients, the biochemical data allowed the diagnosis. Among eleven patients with HCP, ten CPOX mutations were identified, including six novel ones: two frameshift (c.32delG and c.1102delC), two nonsense (p.Cys239Ter and p.Tyr365Ter), one missense (p.Trp275Arg) and one amino acid deletion (p.Gly336del). Moreover, seven previously described PPOX mutations were identified in eight patients with VP. The impacts of CPOX mutations p.Trp275Arg and p.Gly336del, were evaluated using prediction softwares and their functional consequences were studied in a prokaryotic expression system. Both alterations were predicted as deleterious by in silico analysis. Aditionally, when these alleles were expressed in E. coli, only p.Trp275Arg retained some residual activity. These results emphasize the usefulness of integrated the biochemical tests and molecular studies in the diagnosis. Furthermore, they extend knowledge on the molecular heterogeneity of mixed porphyrias in Spain.
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Affiliation(s)
| | | | | | - Silvia Díaz Díaz
- Servicio de Análisis Clínicos, Hospital 12 de Octubre, Madrid, Spain
| | | | | | | | - Manuel Méndez
- Instituto de Investigación Hospital 12 de Octubre, Madrid, Spain.
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Li B, Bridwell-Rabb J. Aerobic Enzymes and Their Radical SAM Enzyme Counterparts in Tetrapyrrole Pathways. Biochemistry 2018; 58:85-93. [PMID: 30365306 DOI: 10.1021/acs.biochem.8b00906] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Microorganisms have lifestyles and metabolism adapted to environmental niches, which can be very broad or highly restricted. Molecular oxygen (O2) is currently variably present in microenvironments and has driven adaptation and microbial differentiation over the course of evolution on Earth. Obligate anaerobes use enzymes and cofactors susceptible to low levels of O2 and are restricted to O2-free environments, whereas aerobes typically take advantage of O2 as a reactant in many biochemical pathways and may require O2 for essential biochemical reactions. In this Perspective, we focus on analogous enzymes found in tetrapyrrole biosynthesis, modification, and degradation that are catalyzed by O2-sensitive radical S-adenosylmethionine (SAM) enzymes and by O2-dependent metalloenzymes. We showcase four transformations for which aerobic organisms use O2 as a cosubstrate but anaerobic organisms do not. These reactions include oxidative decarboxylation, methyl and methylene oxidation, ring formation, and ring cleavage. Furthermore, we highlight biochemically uncharacterized enzymes implicated in reactions that resemble those catalyzed by the parallel aerobic and anaerobic enzymes. Intriguingly, several of these reactions require insertion of an oxygen atom into the substrate, which in aerobic enzymes is facilitated by activation of O2 but in anaerobic organisms requires an alternative mechanism.
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Affiliation(s)
- Bin Li
- Department of Chemistry , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Jennifer Bridwell-Rabb
- Department of Chemistry , University of Michigan , Ann Arbor , Michigan 48109 , United States
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15
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Li K, Fielding EN, Condurso HL, Bruner SD. Probing the structural basis of oxygen binding in a cofactor-independent dioxygenase. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2017; 73:573-580. [DOI: 10.1107/s2059798317007045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 05/10/2017] [Indexed: 11/11/2022]
Abstract
The enzyme DpgC is included in the small family of cofactor-independent dioxygenases. The chemistry of DpgC is uncommon as the protein binds and utilizes dioxygen without the aid of a metal or organic cofactor. Previous structural and biochemical studies identified the substrate-binding mode and the components of the active site that are important in the catalytic mechanism. In addition, the results delineated a putative binding pocket and migration pathway for the co-substrate dioxygen. Here, structural biology is utilized, along with site-directed mutagenesis, to probe the assigned dioxygen-binding pocket. The key residues implicated in dioxygen trafficking were studied to probe the process of binding, activation and chemistry. The results support the proposed chemistry and provide insight into the general mechanism of dioxygen binding and activation.
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16
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Dailey HA, Dailey TA, Gerdes S, Jahn D, Jahn M, O'Brian MR, Warren MJ. Prokaryotic Heme Biosynthesis: Multiple Pathways to a Common Essential Product. Microbiol Mol Biol Rev 2017; 81:e00048-16. [PMID: 28123057 PMCID: PMC5312243 DOI: 10.1128/mmbr.00048-16] [Citation(s) in RCA: 205] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The advent of heme during evolution allowed organisms possessing this compound to safely and efficiently carry out a variety of chemical reactions that otherwise were difficult or impossible. While it was long assumed that a single heme biosynthetic pathway existed in nature, over the past decade, it has become clear that there are three distinct pathways among prokaryotes, although all three pathways utilize a common initial core of three enzymes to produce the intermediate uroporphyrinogen III. The most ancient pathway and the only one found in the Archaea converts siroheme to protoheme via an oxygen-independent four-enzyme-step process. Bacteria utilize the initial core pathway but then add one additional common step to produce coproporphyrinogen III. Following this step, Gram-positive organisms oxidize coproporphyrinogen III to coproporphyrin III, insert iron to make coproheme, and finally decarboxylate coproheme to protoheme, whereas Gram-negative bacteria first decarboxylate coproporphyrinogen III to protoporphyrinogen IX and then oxidize this to protoporphyrin IX prior to metal insertion to make protoheme. In order to adapt to oxygen-deficient conditions, two steps in the bacterial pathways have multiple forms to accommodate oxidative reactions in an anaerobic environment. The regulation of these pathways reflects the diversity of bacterial metabolism. This diversity, along with the late recognition that three pathways exist, has significantly slowed advances in this field such that no single organism's heme synthesis pathway regulation is currently completely characterized.
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Affiliation(s)
- Harry A Dailey
- Department of Microbiology, Department of Biochemistry and Molecular Biology, and Biomedical and Health Sciences Institute, University of Georgia, Athens, Georgia, USA
| | - Tamara A Dailey
- Department of Microbiology, Department of Biochemistry and Molecular Biology, and Biomedical and Health Sciences Institute, University of Georgia, Athens, Georgia, USA
| | - Svetlana Gerdes
- Fellowship for Interpretation of Genomes, Burr Ridge, Illinois, USA
| | - Dieter Jahn
- Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universitaet Braunschweig, Braunschweig, Germany
| | - Martina Jahn
- Institute of Microbiology, Technische Universitaet Braunschweig, Braunschweig, Germany
| | - Mark R O'Brian
- Department of Biochemistry, University at Buffalo, The State University of New York, Buffalo, New York, USA
| | - Martin J Warren
- Department of Biosciences, University of Kent, Canterbury, Kent, United Kingdom
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Barupala DP, Dzul SP, Riggs-Gelasco PJ, Stemmler TL. Synthesis, delivery and regulation of eukaryotic heme and Fe-S cluster cofactors. Arch Biochem Biophys 2016; 592:60-75. [PMID: 26785297 PMCID: PMC4784227 DOI: 10.1016/j.abb.2016.01.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 01/13/2016] [Accepted: 01/14/2016] [Indexed: 11/25/2022]
Abstract
In humans, the bulk of iron in the body (over 75%) is directed towards heme- or Fe-S cluster cofactor synthesis, and the complex, highly regulated pathways in place to accomplish biosynthesis have evolved to safely assemble and load these cofactors into apoprotein partners. In eukaryotes, heme biosynthesis is both initiated and finalized within the mitochondria, while cellular Fe-S cluster assembly is controlled by correlated pathways both within the mitochondria and within the cytosol. Iron plays a vital role in a wide array of metabolic processes and defects in iron cofactor assembly leads to human diseases. This review describes progress towards our molecular-level understanding of cellular heme and Fe-S cluster biosynthesis, focusing on the regulation and mechanistic details that are essential for understanding human disorders related to the breakdown in these essential pathways.
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Affiliation(s)
- Dulmini P Barupala
- Departments of Biochemistry and Molecular Biology, and Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA
| | - Stephen P Dzul
- Departments of Biochemistry and Molecular Biology, and Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA
| | | | - Timothy L Stemmler
- Departments of Biochemistry and Molecular Biology, and Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA.
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18
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Ramanujam VMS, Anderson KE. Porphyria Diagnostics-Part 1: A Brief Overview of the Porphyrias. CURRENT PROTOCOLS IN HUMAN GENETICS 2015; 86:17.20.1-17.20.26. [PMID: 26132003 PMCID: PMC4640448 DOI: 10.1002/0471142905.hg1720s86] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Porphyria diseases are a group of metabolic disorders caused by abnormal functioning of heme biosynthesis enzymes and characterized by excessive accumulation and excretion of porphyrins and their precursors. Precisely which of these chemicals builds up depends on the type of porphyria. Porphyria is not a single disease but a group of nine disorders: acute intermittent porphyria (AIP), hereditary coproporphyria (HCP), variegate porphyria (VP), δ-aminolevulinic acid dehydratase deficiency porphyria (ADP), porphyria cutanea tarda (PCT), hepatoerythropoietic porphyria (HEP), congenital erythropoietic porphyria (CEP), erythropoietic protoporphyria (EPP), and X-linked protoporphyria (XLP). Each porphyria results from overproduction of heme precursors secondary to partial deficiency or, in XLP, increased activity of one of the enzymes of heme biosynthesis. Taken together, all forms of porphyria afflict fewer than 200,000 people in the United States. Based on European studies, the most common porphyria, PCT, has a prevalence of 1 in 10,000, the most common acute porphyria, AlP, has a prevalence of ∼1 in 20,000, and the most common erythropoietic porphyria, EPP, is estimated at 1 in 50,000 to 75,000. CEP is extremely rare, with prevalence estimates of 1 in 1,000,000 or less. Only six cases of ADP are documented. The current porphyria literature is very exhaustive and a brief overview of porphyria diseases is essential in order for the reader to better appreciate the relevance of this area of research prior to undertaking biochemical diagnostics procedures. This unit summarizes the current knowledge on the classification, clinical features, etiology, pathogenesis, and genetics of porphyria diseases.
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Affiliation(s)
| | - Karl Elmo Anderson
- Department of Preventive Medicine and Community Health, The University of Texas Medical Branch, Galveston, Texas 77555-1109
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19
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Sullivan SA, Streit BR, Ferguson EL, Jean PA, McNett DA, Llames LT, DuBois JL. Mass-spectrometric profiling of porphyrins in complex biological samples with fundamental, toxicological, and pharmacological applications. Anal Biochem 2015; 478:82-9. [PMID: 25769421 DOI: 10.1016/j.ab.2015.03.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 02/19/2015] [Accepted: 03/03/2015] [Indexed: 10/23/2022]
Abstract
Rapid, high-throughput, and quantitative evaluations of biological metabolites in complex milieu are increasingly required for biochemical, toxicological, pharmacological, and environmental analyses. They are also essential for the development, testing, and improvement of new commercial chemical products. We demonstrate the application of ultra-high performance liquid chromatography-mass spectrometry (uHPLC-MS), employing an electrospray ionization source and a high accuracy quadrupole time-of-flight mass analyzer, for the identification and quantification of a series of porphyrin derivatives in liver: a matrix of particular relevance in toxicological or pharmacological testing. Exact mass is used to identify and quantify the metabolites. Chromatography enhances sensitivity and alleviates potential saturation issues by fanning out the contents of a complex sample before their injection into the spectrometer, but is not strictly necessary for the analysis. Extraction and sample treatment procedures are evaluated and matrix effects discussed. Using this method, the known mechanism of action of a well-characterized porphyrinogenic agent was verified in liver extracts from treated rats. The method was also validated for use with bacterial cells. This exact-mass method uses workhorse instruments available in many laboratories, providing a highly flexible alternative to existing HPLC- and MS/MS-based approaches for the simultaneous analysis of multiple compounds in biological media.
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Affiliation(s)
- Sarah A Sullivan
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Bennett R Streit
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA; Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59713, USA
| | - Ethan L Ferguson
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Paul A Jean
- Health and Environmental Sciences, Dow Corning Corporation, Auburn, MI 48611, USA
| | - Debra A McNett
- Health and Environmental Sciences, Dow Corning Corporation, Auburn, MI 48611, USA
| | - Louis T Llames
- Health and Environmental Sciences, Dow Corning Corporation, Auburn, MI 48611, USA.
| | - Jennifer L DuBois
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59713, USA.
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20
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Ligand binding reveals a role for heme in translationally-controlled tumor protein dimerization. PLoS One 2014; 9:e112823. [PMID: 25396429 PMCID: PMC4232476 DOI: 10.1371/journal.pone.0112823] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 10/16/2014] [Indexed: 11/19/2022] Open
Abstract
The translationally-controlled tumor protein (TCTP) is a highly conserved, ubiquitously expressed, abundant protein that is broadly distributed among eukaryotes. Its biological function spans numerous cellular processes ranging from regulation of the cell cycle and microtubule stabilization to cell growth, transformation, and death processes. In this work, we propose a new function for TCTP as a “buffer protein” controlling cellular homeostasis. We demonstrate that binding of hemin to TCTP is mediated by a conserved His-containing motif (His76His77) followed by dimerization, an event that involves ligand-mediated conformational changes and that is necessary to trigger TCTP's cytokine-like activity. Mutation in both His residues to Ala prevents hemin from binding and abrogates oligomerization, suggesting that the ligand site localizes at the interface of the oligomer. Unlike heme, binding of Ca2+ ligand to TCTP does not alter its monomeric state; although, Ca2+ is able to destabilize an existing TCTP dimer created by hemin addition. In agreement with TCTP's proposed buffer function, ligand binding occurs at high concentration, allowing the “buffer” condition to be dissociated from TCTP's role as a component of signal transduction mechanisms.
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21
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Bali S, Palmer DJ, Schroeder S, Ferguson SJ, Warren MJ. Recent advances in the biosynthesis of modified tetrapyrroles: the discovery of an alternative pathway for the formation of heme and heme d 1. Cell Mol Life Sci 2014; 71:2837-63. [PMID: 24515122 PMCID: PMC11113276 DOI: 10.1007/s00018-014-1563-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 12/19/2013] [Accepted: 01/10/2014] [Indexed: 02/05/2023]
Abstract
Hemes (a, b, c, and o) and heme d 1 belong to the group of modified tetrapyrroles, which also includes chlorophylls, cobalamins, coenzyme F430, and siroheme. These compounds are found throughout all domains of life and are involved in a variety of essential biological processes ranging from photosynthesis to methanogenesis. The biosynthesis of heme b has been well studied in many organisms, but in sulfate-reducing bacteria and archaea, the pathway has remained a mystery, as many of the enzymes involved in these characterized steps are absent. The heme pathway in most organisms proceeds from the cyclic precursor of all modified tetrapyrroles uroporphyrinogen III, to coproporphyrinogen III, which is followed by oxidation of the ring and finally iron insertion. Sulfate-reducing bacteria and some archaea lack the genetic information necessary to convert uroporphyrinogen III to heme along the "classical" route and instead use an "alternative" pathway. Biosynthesis of the isobacteriochlorin heme d 1, a cofactor of the dissimilatory nitrite reductase cytochrome cd 1, has also been a subject of much research, although the biosynthetic pathway and its intermediates have evaded discovery for quite some time. This review focuses on the recent advances in the understanding of these two pathways and their surprisingly close relationship via the unlikely intermediate siroheme, which is also a cofactor of sulfite and nitrite reductases in many organisms. The evolutionary questions raised by this discovery will also be discussed along with the potential regulation required by organisms with overlapping tetrapyrrole biosynthesis pathways.
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Affiliation(s)
- Shilpa Bali
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | - David J. Palmer
- School of Biosciences, University of Kent, Kent, Canterbury, CT2 7NZ UK
| | - Susanne Schroeder
- School of Biosciences, University of Kent, Kent, Canterbury, CT2 7NZ UK
| | - Stuart J. Ferguson
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | - Martin J. Warren
- School of Biosciences, University of Kent, Kent, Canterbury, CT2 7NZ UK
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22
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Abstract
Leishmania major was proposed to either utilize haem from its host or partially synthesize the tetrapyrrole from host provided precursors. However, only indirect evidence was available for this partial late haem biosynthetic pathway. Here, we demonstrate that the LMJF_06_1280 gene of L. major encodes a HemG-type PPO (protoporphyrinogen IX oxidase) catalysing the oxidation of protoporphyrinogen IX to protoporphyrin IX. Interestingly, trypanosomatids are currently the only known eukaryotes possessing HemG-type enzymes. The LMJF_06_1280 gene forms a potential transcriptional unit with LMJF_06_1270 encoding CPO (coproporphyrinogen III oxidase) and with LMJF_06_1290 for a cytochrome b5. In vivo function of the L. major hemG gene was shown by the functional complementation of the Escherichia coli ΔhemG strain LG285. Restored haem formation in E. coli was observed using HPLC analyses. Purified recombinant L. major HemG revealed PPO activity in vitro using different ubiquinones and triphenyltetrazolium as electron acceptors. FMN was identified as the L. major HemG cofactor. Active site residues were found to be essential for HemG catalysis. These data in combination with the solved crystal structures of L. major CPO and the physiological proof of a ferrochelatase activity provide clear-cut evidence for a partial haem biosynthetic pathway in L. major.
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23
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Thierbach S, Bui N, Zapp J, Chhabra SR, Kappl R, Fetzner S. Substrate-assisted O2 activation in a cofactor-independent dioxygenase. ACTA ACUST UNITED AC 2014; 21:217-25. [PMID: 24388758 DOI: 10.1016/j.chembiol.2013.11.013] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 11/22/2013] [Accepted: 11/27/2013] [Indexed: 11/29/2022]
Abstract
In contrast to the majority of O2-activating enzymes, which depend on an organic cofactor or a metal ion for catalysis, a particular group of structurally unrelated oxygenases is functional without any cofactor. In this study, we characterized the mechanism of O2 activation in the reaction pathway of a cofactor-independent dioxygenase with an α/β-hydrolase fold, which catalyzes the oxygenolytic cleavage of 2-alkyl-3-hydroxy-4(1H)-quinolones. Chemical analysis and electron paramagnetic resonance spectroscopic data revealed that O2 activation in the enzyme's active site is substrate-assisted, relying on single electron transfer from the bound substrate anion to O2 to form a radical pair, which recombines to a C2-peroxide intermediate. Thus, an oxygenase can function without a cofactor, if the organic substrate itself, after activation to a (carb)anion by an active-site base, is intrinsically reactive toward molecular oxygen.
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Affiliation(s)
- Sven Thierbach
- Institute of Molecular Microbiology and Biotechnology, University of Münster, Corrensstrasse 3, 48149 Münster, Germany
| | - Nguyen Bui
- Department of Biophysics, School of Medicine, Saarland University, Clinical Center, Building 76, 66421 Homburg, Germany
| | - Josef Zapp
- Pharmaceutical Biology, Saarland University, Campus, Building C2, 66123 Saarbrücken, Germany
| | - Siri Ram Chhabra
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Reinhard Kappl
- Department of Biophysics, School of Medicine, Saarland University, Clinical Center, Building 76, 66421 Homburg, Germany
| | - Susanne Fetzner
- Institute of Molecular Microbiology and Biotechnology, University of Münster, Corrensstrasse 3, 48149 Münster, Germany.
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24
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Kim DHT, Hino R, Adachi Y, Kobori A, Taketani S. The enzyme engineering of mutant homodimer and heterodimer of coproporphyinogen oxidase contributes to new insight into hereditary coproporphyria and harderoporphyria. J Biochem 2013; 154:551-9. [DOI: 10.1093/jb/mvt086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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25
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Jiménez-Jiménez FJ, Agúndez JAG, Martínez C, Navacerrada F, Plaza-Nieto JF, Pilo-de-la-Fuente B, Alonso-Navarro H, García-Martín E. Hereditary Coproporphyria Associated with the Q306X Mutation in the Coproporphyrin Oxidase Gene Presenting with Acute Ataxia. Tremor Other Hyperkinet Mov (N Y) 2013; 3:tre-03-151-4162-1. [PMID: 24156084 PMCID: PMC3777436 DOI: 10.7916/d8df6pxw] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Accepted: 02/26/2013] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Hereditary coproporphyria (HCPO) is a low-penetrance, autosomal dominant, acute hepatic porphyria characterized by the overproduction and excretion of coproporphyrin. The most common neurological manifestations of this entity include peripheral, predominantly motor dysfunction, and central nervous system dysfunction. Ataxia associated with HCPO has not been reported previously. The aim of this article is to report a patient with HCPO presenting with acute ataxia. CASE REPORT We describe a 44-year-old patient presenting clinically with acute ataxia who was diagnosed with HCPO; mutations were analyzed in the coproporphyrin-oxidase III (CPOX) gene in the patient and in six asymptomatic first-degree relatives. DISCUSSION The patient was heterozygous for a mutation causing the amino acid exchange Q306X in the CPOX gene. No relatives carried the same or another mutation in the CPOX gene. HCPO should be considered in the differential diagnosis for patients presenting with ataxia.
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Affiliation(s)
- Félix Javier Jiménez-Jiménez
- Section of Neurology, Hospital Universitario del Sureste, Arganda del Rey, Madrid, Spain,*To whom correspondence should be addressed. E-mail: ;
| | | | - Carmen Martínez
- Department of Pharmacology, University of Extremadura, Cáceres, Spain
| | - Francisco Navacerrada
- Section of Neurology, Hospital Universitario del Sureste, Arganda del Rey, Madrid, Spain
| | | | | | | | - Elena García-Martín
- Department of Biochemistry and Molecular Biology, University of Extremadura, Cáceres, Spain
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26
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Abstract
Heme, which is composed of iron and the small organic molecule protoporphyrin, is an essential component of hemoglobin as well as a variety of physiologically important hemoproteins. During erythropoiesis, heme synthesis is induced before, and is essential for, globin synthesis. Although all cells possess the ability to synthesize heme, there are distinct differences between regulation of the pathway in developing erythroid cells and all other types of cells. Disorders that compromise the ability of the developing red cell to synthesize heme can have profound medical implications. The biosynthetic pathway for heme and key regulatory features are reviewed herein, along with specific human genetic disorders that arise from defective heme synthesis such as X-linked sideroblastic anemia and erythropoietic protoporphyria.
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Affiliation(s)
- Harry A Dailey
- Department of Microbiology, Department of Biochemistry and Molecular Biology, Biomedical and Health Sciences Institute, University of Georgia, Athens, GA 30602, USA.
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27
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Rhee HW, Zou P, Udeshi ND, Martell JD, Mootha VK, Carr SA, Ting AY. Proteomic mapping of mitochondria in living cells via spatially restricted enzymatic tagging. Science 2013; 339:1328-1331. [PMID: 23371551 DOI: 10.1126/science.1230593] [Citation(s) in RCA: 893] [Impact Index Per Article: 81.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Microscopy and mass spectrometry (MS) are complementary techniques: The former provides spatiotemporal information in living cells, but only for a handful of recombinant proteins at a time, whereas the latter can detect thousands of endogenous proteins simultaneously, but only in lysed samples. Here, we introduce technology that combines these strengths by offering spatially and temporally resolved proteomic maps of endogenous proteins within living cells. Our method relies on a genetically targetable peroxidase enzyme that biotinylates nearby proteins, which are subsequently purified and identified by MS. We used this approach to identify 495 proteins within the human mitochondrial matrix, including 31 not previously linked to mitochondria. The labeling was exceptionally specific and distinguished between inner membrane proteins facing the matrix versus the intermembrane space (IMS). Several proteins previously thought to reside in the IMS or outer membrane, including protoporphyrinogen oxidase, were reassigned to the matrix by our proteomic data and confirmed by electron microscopy. The specificity of peroxidase-mediated proteomic mapping in live cells, combined with its ease of use, offers biologists a powerful tool for understanding the molecular composition of living cells.
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Affiliation(s)
- Hyun-Woo Rhee
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Peng Zou
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | | - Jeffrey D Martell
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Vamsi K Mootha
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Department of Molecular Biology, Massachusetts General Hospital, and Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Steven A Carr
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Alice Y Ting
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
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28
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Hamza I, Dailey HA. One ring to rule them all: trafficking of heme and heme synthesis intermediates in the metazoans. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1823:1617-32. [PMID: 22575458 DOI: 10.1016/j.bbamcr.2012.04.009] [Citation(s) in RCA: 167] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 04/15/2012] [Accepted: 04/19/2012] [Indexed: 12/17/2022]
Abstract
The appearance of heme, an organic ring surrounding an iron atom, in evolution forever changed the efficiency with which organisms were able to generate energy, utilize gasses and catalyze numerous reactions. Because of this, heme has become a near ubiquitous compound among living organisms. In this review we have attempted to assess the current state of heme synthesis and trafficking with a goal of identifying crucial missing information, and propose hypotheses related to trafficking that may generate discussion and research. The possibilities of spatially organized supramolecular enzyme complexes and organelle structures that facilitate efficient heme synthesis and subsequent trafficking are discussed and evaluated. Recently identified players in heme transport and trafficking are reviewed and placed in an organismal context. Additionally, older, well established data are reexamined in light of more recent studies on cellular organization and data available from newer model organisms. This article is part of a Special Issue entitled: Cell Biology of Metals.
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Affiliation(s)
- Iqbal Hamza
- Department of Animal & Avian Sciences, University of Maryland, College Park, MD 20742, USA.
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29
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Ma E, Mar V, Varigos G, Nicoll A, Ross G. Haem arginate as effective maintenance therapy for hereditary coproporphyria. Australas J Dermatol 2011; 52:135-8. [PMID: 21605099 DOI: 10.1111/j.1440-0960.2011.00747.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A 35-year-old woman presented with skin fragility and photosensitivity with blisters affecting her face and hands. Other symptoms included intermittent headache, fatigue, abdominal pain and nausea. Porphyrin studies were markedly raised, with features consistent with hereditary coproporphyria (HCP). Despite strict precautions, symptoms remained significantly problematic. Regular haem arginate infusions of 3 mg/kg per day over 4 days on a monthly basis were commenced and resulted in significant improvement of the patient's symptoms and a reduction in urinary porphobilinogen. Although haem arginate infusion is known as a treatment for severe acute attacks of HCP, the effectiveness of regular infusions as maintenance therapy has not been established. This is the first report of effective symptom control correlating with normalization of biochemical markers in a patient receiving regular haem arginate infusions for the treatment of HCP.
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Affiliation(s)
- Ellen Ma
- Departments of Dermatology Gastroenterology, The Royal Melbourne Hospital, Parkville, Victoria, Australia.
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30
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Silva PJ, Ramos MJ. Computational characterization of the substrate-binding mode in coproporphyrinogen III oxidase. J Phys Chem B 2011; 115:1903-10. [PMID: 21291195 DOI: 10.1021/jp110289d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxygen-dependent coproporphyrinogen III oxidase catalyzes the sequential decarboxylation of the propionate substituents present on the A and B rings of coproporphyrinogen III in the heme biosynthetic pathway. Although extensive experimental investigation of this enzyme has already afforded many insights into its reaction mechanism, several key features (such as the substrate binding mode, the characterization of the active site, and the initial substrate protonation state) remain poorly described. The molecular dynamics simulations described in this paper enabled the determination of a very promising substrate binding mode and the extensive characterization of the enzyme active site. The proposed binding mode is fully consistent with the known selectivity of the active site toward substituted tetrapyrroles and explains the lack of activity of the H131A, R135A, D274A, and R275A mutants and the reasons behind the nonoccurrence of catalysis on the C and D rings of the tetrapyrrole. An important role in this binding mode is fulfilled by G276, as its carbonyl oxygen intervenes in the substrate anchoring by hydrogen bonding its ring D pyrrole NH group. The presence of this interaction (which is only possible with the protonated NH pyrrole group) and the absence of positively charged side chains close to the pyrrole nitrogen (which might stabilize the N-deprotonated pyrrole postulated in some mechanistic proposals) show that the pyrrole ring is very unlikely to undergo deprotonation during the catalytic cycle and allow the discrimination between the previously postulated mechanistic proposals.
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Affiliation(s)
- Pedro J Silva
- REQUIMTE, Faculdade de Ciências da Saúde, Universidade Fernando Pessoa, Rua Carlos da Maia, 296, 4200-150 Porto-Portugal
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31
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Hasanoglu A, Balwani M, Kasapkara CS, Ezgü FS, Okur I, Tümer L, Cakmak A, Nazarenko I, Yu C, Clavero S, Bishop DF, Desnick RJ. Harderoporphyria due to homozygosity for coproporphyrinogen oxidase missense mutation H327R. J Inherit Metab Dis 2011; 34:225-31. [PMID: 21103937 PMCID: PMC3091031 DOI: 10.1007/s10545-010-9237-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 10/08/2010] [Accepted: 10/19/2010] [Indexed: 10/18/2022]
Abstract
Hereditary coproporphyria (HCP) is an autosomal dominant acute hepatic porphyria due to the half-normal activity of the heme biosynthetic enzyme, coproporphyrinogen oxidase (CPOX). The enzyme catalyzes the step-wise oxidative decarboxylation of the heme precursor, coproporphyrinogen III, to protoporphyrinogen IX via a tricarboxylic intermediate, harderoporphyrinogen. In autosomal dominant HCP, the deficient enzymatic activity results primarily in the accumulation of coproporphyrin III. To date, only a few homozygous HCP patients have been described, most having Harderoporphyria, a rare variant due to specific CPOX mutations that alter enzyme residues D400-K404, most patients described to date having at least one K404E allele. Here, we describe a Turkish male infant, the product of a consanguineous union, who presented with the Harderoporphyria phenotype including neonatal hyperbilirubinemia, hemolytic anemia, hepatosplenomegaly, and skin lesions when exposed to UV light. He was homoallelic for the CPOX missense mutation, c.980A>G (p.H327R), and had massively increased urinary uroporphyrins I and III (9,250 and 2,910 μM, respectively) and coproporphyrins I and III (895 and 19,400 μM, respectively). The patient expired at 5 months of age from an apparent acute neurologic porphyric attack. Structural studies predicted that p.H327R interacts with residue W399 in the CPOX active site, thereby accounting for the Harderoporphyria phenotype.
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Affiliation(s)
- Alev Hasanoglu
- Department of Pediatric Metabolism and Nutrition, Gazi University Hospital, Ankara, Turkey
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32
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Lash TD, Lamm TR, Schaber JA, Chung WH, Johnson EK, Jones MA. Normal and abnormal heme biosynthesis. Part 7. Synthesis and metabolism of coproporphyrinogen-III analogues with acetate or butyrate side chains on rings C and D. Development of a modified model for the active site of coproporphyrinogen oxidase. Bioorg Med Chem 2011; 19:1492-504. [PMID: 21277781 DOI: 10.1016/j.bmc.2010.12.053] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 12/20/2010] [Accepted: 12/23/2010] [Indexed: 11/19/2022]
Abstract
Analogues of coproporphyrinogen-III have been prepared with acetate or butyrate groups attached to the C and D pyrrolic subunits. The corresponding porphyrin methyl esters were synthesized by first generating a,c-biladienes by reacting a dipyrrylmethane with pyrrole aldehydes in the presence of HBr. Cyclization with copper(II) chloride in DMF, followed by demetalation with 15% H(2)SO(4)-TFA and reesterification, gave the required porphyrins in excellent yields. Hydrolysis with 25% hydrochloric acid and reduction with sodium-amalgam gave novel diacetate and dibutyrate porphyrinogens 9. Diacetate 9a was incubated with chicken red cell hemolysates (CRH), but gave complex results due to the combined action of two of the enzymes present in these preparations. Separation of uroporphyrinogen decarboxylase (URO-D) from coproporphyrinogen oxidase (CPO) allowed the effects of both enzymes on the diacetate substrate to be assessed. Porphyrinogen 9a proved to be a relatively poor substrate for CPO compared to the natural substrate coproporphyrinogen-III, and only the A ring propionate moiety was processed to a significant extent. Similar results were obtained for incubations of 9a with purified human recombinant CPO. Diacetate 9a was also a substrate for URO-D and a porphyrinogen monoacetate was the major product in this case; however, some conversion of a second acetate unit was also evident. The dibutyrate porphyrinogen 9b was only recognized by the enzyme CPO, but proved to be a modest substrate for incubations with CRH. However, 9b was an excellent substrate for purified human recombinant CPO. The major product for these incubations was a monovinylporphyrinogen, but some divinyl product was also generated in incubations using purified recombinant human CPO. The incubation products were converted into the corresponding porphyrin methyl esters, and these were characterized by proton NMR spectroscopy and mass spectrometry. The results extend our understanding of substrate recognition and catalysis for this intriguing enzyme and have allowed us to extend the active site model for CPO. In addition, the competitive action of both URO-D and CPO on the same diacetate porphyrinogen substrate provides additional perspectives on the potential existence of abnormal pathways for heme biosynthesis.
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Affiliation(s)
- Timothy D Lash
- Department of Chemistry, Illinois State University, Normal, IL 61790-4160, United States.
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Qin X, Tan Y, Wang L, Wang Z, Wang B, Wen X, Yang G, Xi Z, Shen Y. Structural insight into human variegate porphyria disease. FASEB J 2010; 25:653-64. [PMID: 21048046 DOI: 10.1096/fj.10-170811] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Human protoporphyrinogen IX oxidase (hPPO), a mitochondrial inner membrane protein, converts protoporphyrinogen IX to protoporphyrin IX in the heme biosynthetic pathway. Mutations in the hPPO gene cause the inherited human disease variegate porphyria (VP). In this study, we report the crystal structure of hPPO in complex with the coenzyme flavin adenine dinucleotide (FAD) and the inhibitor acifluorfen at a resolution of 1.9 Å. The structural and biochemical analyses revealed the molecular details of FAD and acifluorfen binding to hPPO as well as the interactions of the substrate with hPPO. Structural analysis and gel chromatography indicated that hPPO is a monomer rather than a homodimer in vitro. The founder-effect mutation R59W in VP patients is most likely caused by a severe electrostatic hindrance in the hydrophilic binding pocket involving the bulky, hydrophobic indolyl ring of the tryptophan. Forty-seven VP-causing mutations were purified by chromatography and kinetically characterized in vitro. The effect of each mutation was demonstrated in the high-resolution crystal structure.
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Affiliation(s)
- Xiaohong Qin
- College of Life Science, Nankai University, Tianjin, China 300071
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Abstract
Porphyrias are a group of inherited and acquired metabolic disorders due to a defect in haem biosynthesis. An enzymatic defect at different steps of haem synthesis leads to tissue accumulation and excessive excretion of porphyrins and/or their toxic precursors. The specific patterns of accumulation determine the variety of clinical manifestations, ranging from acute neurovisceral attacks to skin lesions and liver disease. Most enzyme defects represent partial deficiencies, while familial cases are linked to autosomal or recessive traits. The incomplete penetrance of the genetic defects often requires the triggering or aggravating effect of host-related or environmental factors. While genetics has a role in confirming clinical suspicion and in family screening, biochemical and clinical studies are still central in the diagnosis.
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Affiliation(s)
- Antonello Pietrangelo
- Division of Internal Medicine, Center for Hereditary Liver Diseases, Mario Coppo Liver Research Center, University Hospital of Modena, Via del Pozzo 71, 41100, Modena, Italy.
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Layer G, Reichelt J, Jahn D, Heinz DW. Structure and function of enzymes in heme biosynthesis. Protein Sci 2010; 19:1137-61. [PMID: 20506125 DOI: 10.1002/pro.405] [Citation(s) in RCA: 213] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Tetrapyrroles like hemes, chlorophylls, and cobalamin are complex macrocycles which play essential roles in almost all living organisms. Heme serves as prosthetic group of many proteins involved in fundamental biological processes like respiration, photosynthesis, and the metabolism and transport of oxygen. Further, enzymes such as catalases, peroxidases, or cytochromes P450 rely on heme as essential cofactors. Heme is synthesized in most organisms via a highly conserved biosynthetic route. In humans, defects in heme biosynthesis lead to severe metabolic disorders called porphyrias. The elucidation of the 3D structures for all heme biosynthetic enzymes over the last decade provided new insights into their function and elucidated the structural basis of many known diseases. In terms of structure and function several rather unique proteins were revealed such as the V-shaped glutamyl-tRNA reductase, the dipyrromethane cofactor containing porphobilinogen deaminase, or the "Radical SAM enzyme" coproporphyrinogen III dehydrogenase. This review summarizes the current understanding of the structure-function relationship for all heme biosynthetic enzymes and their potential interactions in the cell.
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Affiliation(s)
- Gunhild Layer
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig D-38106, Germany
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Lash TD, Mani UN, Keck ASIM, Jones MA. Normal and abnormal heme biosynthesis. 6. Synthesis and metabolism of a series of monovinylporphyrinogens related to harderoporphyrinogen. Further insights into the oxidative decarboxylation of porphyrinogen substrates by coproporphyrinogen oxidase. J Org Chem 2010; 75:3183-92. [PMID: 20387847 DOI: 10.1021/jo100083t] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of vinylporphyrinogens were prepared to probe the enzyme coproporphyrinogen oxidase (CPO). Six (2-chloroethyl)porphyrins were synthesized from a common dipyrrylmethane via a,c-biladiene intermediates in excellent yields. Subsequent dehydrohalogenation with DBU in refluxing DMF then gave the required vinylporphyrin methyl esters, including harderoporphyrin-I, harderoporphyrin-III, and isoharderoporphyrin. The corresponding porphyrinogen carboxylic acids were incubated with chicken red cell hemolysates, which contain the enzyme CPO, and the products analyzed. The 17-ethyl analogue of harderoporphyrinogen-III, but not its 13-ethyl isomer, was shown to be an excellent substrate for CPO in accord with a proposed model for the active site of this enzyme. In addition, harderoporphyrinogen-VII, the monovinyl intermediate in the metabolism of coproporphyrinogen-IV, was shown to be an equally good substrate for this enzyme. However, isoharderoporphyrinogen, which lacks the correct ordering of peripheral substituents, was also a substrate for CPO. Furthermore, a nonnatural type I isomer of harderoporphyrinogen was shown to be acted on by CPO, but in this case further metabolism was noted and this afforded an unprecedented trivinyl porphyrinogen product. The corresponding porphyrin methyl ester was isolated and characterized by FAB MS and proton NMR spectroscopy. The results from these studies allow the binding requirements of CPO to be further assessed and provide a series of substrates to investigate this poorly understood enzyme.
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Affiliation(s)
- Timothy D Lash
- Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, USA.
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Nagaraj VA, Prasad D, Arumugam R, Rangarajan PN, Padmanaban G. Characterization of coproporphyrinogen III oxidase in Plasmodium falciparum cytosol. Parasitol Int 2010. [DOI: 10.1016/j.parint.2009.12.001 10.1016/j.molbiopara.2009.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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38
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Cofactor-independent oxidases and oxygenases. Appl Microbiol Biotechnol 2010; 86:791-804. [DOI: 10.1007/s00253-010-2455-0] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Revised: 01/14/2010] [Accepted: 01/14/2010] [Indexed: 10/19/2022]
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Nagaraj VA, Prasad D, Arumugam R, Rangarajan PN, Padmanaban G. Characterization of coproporphyrinogen III oxidase in Plasmodium falciparum cytosol. Parasitol Int 2009; 59:121-7. [PMID: 20006984 DOI: 10.1016/j.parint.2009.12.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Revised: 11/28/2009] [Accepted: 12/07/2009] [Indexed: 10/20/2022]
Abstract
A unique hybrid pathway has been proposed for de novo heme biosynthesis in Plasmodium falciparum involving three different compartments of the parasite, namely mitochondrion, apicoplast and cytosol. While parasite mitochondrion and apicoplast have been shown to harbor key enzymes of the pathway, there has been no experimental evidence for the involvement of parasite cytosol in heme biosynthesis. In this study, a recombinant P. falciparum coproporphyrinogen III oxidase (rPfCPO) was produced in E. coli and confirmed to be active under aerobic conditions. rPfCPO behaved as a monomer of 61kDa molecular mass in gel filtration analysis. Immunofluorescence studies using antibodies to rPfCPO suggested that the enzyme was present in the parasite cytosol. These results were confirmed by detection of enzyme activity only in the parasite soluble fraction. Western blot analysis with anti-rPfCPO antibodies also revealed a 58kDa protein only in this fraction and not in the membrane fraction. The cytosolic presence of PfCPO provides evidence for a hybrid heme-biosynthetic pathway in the malarial parasite.
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Li T, Woods JS. Cloning, expression, and biochemical properties of CPOX4, a genetic variant of coproporphyrinogen oxidase that affects susceptibility to mercury toxicity in humans. Toxicol Sci 2009; 109:228-36. [PMID: 19339664 DOI: 10.1093/toxsci/kfp066] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Coproporphyrinogen oxidase (CPOX) catalyzes the two-step decarboxylation of coproporphyrinogen-III to protoporphyrinogen-IX in the heme biosynthetic pathway. Previously we described a specific polymorphism (A814C) in exon 4 of the human CPOX gene (CPOX4) and demonstrated that CPOX4 is associated with both modified urinary porphyrin excretion and increased neurobehavioral deficits among human subjects with low-level mercury (Hg) exposure. Here, we sought to characterize the gene products of CPOX and CPOX4 with respect to biochemical and kinetic properties. Coproporphyrinogen-III was incubated with recombinantly expressed and purified human CPOX and CPOX4 enzymes at various substrate concentrations, with or without Hg(2+) present. Both CPOX and CPOX4 formed protoporphyrinogen-IX from coproporphyrinogen-III; however, the affinity of CPOX4 was twofold lower than that of CPOX (CPOX K(m) = 0.30 microM, V(max) = 0.52 pmol protoporphyrin-IX; CPOX4 K(m) = 0.54 microM, V(max) = 0.33 pmol protoporphyrin-IX). Hg(2+) specifically inhibited the second step of coproporphyrinogen-III decarboxylation (harderoporphyrinogen to protoporphyrinogen-IX) in a dose dependent manner. We also compared the catalytic activities of CPOX and CPOX4 in human liver samples. The specific activities of CPOX in mutant livers were significantly lower (40-50%) than those of either wild-type or heterozygous. Additionally, enzymes from mutant, heterozygous and wild-type livers were comparably inhibited by Hg(2+) (10 microM), decreasing CPOX4 activity to 25% that of the wild-type enzyme. These findings suggest that CPOX4 may predispose to impaired heme biosynthesis, which is limited further by Hg exposure. These effects may underlie increased susceptibility to neurological deficits previously observed in Hg-exposed humans with CPOX4.
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Affiliation(s)
- Tingting Li
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington 98105, USA
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41
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Erupciones inflamatorias y purpúricas. DERMATOLOGÍA NEONATAL 2009. [PMCID: PMC7161408 DOI: 10.1016/b978-84-8086-390-2.50019-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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42
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Wang Y, Gatti P, Sadílek M, Scott CR, Turecek F, Gelb MH. Direct assay of enzymes in heme biosynthesis for the detection of porphyrias by tandem mass spectrometry. Uroporphyrinogen decarboxylase and coproporphyrinogen III oxidase. Anal Chem 2008; 80:2599-605. [PMID: 18294003 DOI: 10.1021/ac702130n] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report new assays of enzymes uroporphyrinogen decarboxylase (UROD) and coproporphyrinogen III oxidase (CPO) in the heme biosynthetic pathway. The assays were developed for use in clinical diagnostics of inherited disorders porphyria cutanea tarda and hereditary coproporphyria, respectively. Electrospray ionization tandem mass spectrometry is used to monitor the decarboxylation of pentaporphyrinogen I or uroporphyrinogen III catalyzed by UROD and to determine the enzyme activity in human erythrocytes by measuring the production of coproporphyrinogen I or III. The Km value for pentaporphyrinogen I was measured as 0.17 +/- 0.03 microM. A mass spectrometric assay was also developed for the two-step decarboxylative oxidation of coproporphyrinogen III to protoporphyrinogen IX catalyzed by CPO in mitochondria from human lymphocytes (Km = 0.066 +/- 0.009 microM). The assays show good reproducibility, use simple workup by liquid-liquid extraction of enzymatic products, and employ commercially available substrates and internal standards.
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Affiliation(s)
- Yuesong Wang
- Departments of Chemistry, Pediatrics, and Biochemistry, University of Washington, Seattle, Washington 98195-1700, USA
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43
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Heinemann IU, Jahn M, Jahn D. The biochemistry of heme biosynthesis. Arch Biochem Biophys 2008; 474:238-51. [PMID: 18314007 DOI: 10.1016/j.abb.2008.02.015] [Citation(s) in RCA: 226] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Revised: 02/14/2008] [Accepted: 02/14/2008] [Indexed: 02/03/2023]
Abstract
Heme is an integral part of proteins involved in multiple electron transport chains for energy recovery found in almost all forms of life. Moreover, heme is a cofactor of enzymes including catalases, peroxidases, cytochromes of the P(450) class and part of sensor molecules. Here the step-by-step biosynthesis of heme including involved enzymes, their mechanisms and detrimental health consequences caused by their failure are described. Unusual and challenging biochemistry including tRNA-dependent reactions, radical SAM enzymes and substrate derived cofactors are reported.
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Affiliation(s)
- Ilka U Heinemann
- Institute of Microbiology, Technical University of Braunschweig, Spielmannstr. 7, D-38106 Braunschweig, Germany
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44
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Baselga E, Torrelo A. Inflammatory and Purpuric Eruptions. NEONATAL DERMATOLOGY 2008. [PMCID: PMC7315339 DOI: 10.1016/b978-1-4160-3432-2.50022-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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45
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Rockwell NC, Lagarias JC. Flexible mapping of homology onto structure with homolmapper. BMC Bioinformatics 2007; 8:123. [PMID: 17428344 PMCID: PMC1955750 DOI: 10.1186/1471-2105-8-123] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Accepted: 04/11/2007] [Indexed: 12/19/2022] Open
Abstract
Background Over the past decade, a number of tools have emerged for the examination of homology relationships among protein sequences in a structural context. Most recent software implementations for such analysis are tied to specific molecular viewing programs, which can be problematic for collaborations involving multiple viewing environments. Incorporation into larger packages also adds complications for users interested in adding their own scoring schemes or in analyzing proteins incorporating unusual amino acid residues such as selenocysteine. Results We describe homolmapper, a command-line application for mapping information from a multiple protein sequence alignment onto a protein structure for analysis in the viewing software of the user's choice. Homolmapper is small (under 250 K for the application itself) and is written in Python to ensure portability. It is released for non-commercial use under a modified University of California BSD license. Homolmapper permits facile import of additional scoring schemes and can incorporate arbitrary additional amino acids to allow handling of residues such as selenocysteine or pyrrolysine. Homolmapper also provides tools for defining and analyzing subfamilies relative to a larger alignment, for mutual information analysis, and for rapidly visualizing the locations of mutations and multi-residue motifs. Conclusion Homolmapper is a useful tool for analysis of homology relationships among proteins in a structural context. There is also extensive, example-driven documentation available. More information about homolmapper is available at .
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Affiliation(s)
- Nathan C Rockwell
- Section of Molecular and Cellular Biology, University of California, Davis, California 95616, USA
| | - J Clark Lagarias
- Section of Molecular and Cellular Biology, University of California, Davis, California 95616, USA
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Stephenson JR, Stacey JA, Morgenthaler JB, Friesen JA, Lash TD, Jones MA. Role of aspartate 400, arginine 262, and arginine 401 in the catalytic mechanism of human coproporphyrinogen oxidase. Protein Sci 2007; 16:401-10. [PMID: 17242372 PMCID: PMC2203308 DOI: 10.1110/ps.062636907] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Coproporphyrinogen oxidase (CPO) is the sixth enzyme in the heme biosynthetic pathway, catalyzing two sequential oxidative decarboxylations of propionate moieties on coproporphyrinogen-III forming protoporphyrinogen-IX through a monovinyl intermediate, harderoporphyrinogen. Site-directed mutagenesis studies were carried out on three invariant amino acids, aspartate 400, arginine 262, and arginine 401, to determine residue contribution to substrate binding and/or catalysis by human recombinant CPO. Kinetic analyses were performed on mutant enzymes incubated with three substrates, coproporphyrinogen-III, harderoporphyrinogen, or mesoporphyrinogen-VI, in order to determine catalytic ability to perform the first and/or second oxidative decarboxylation. When Asp400 was mutated to alanine no divinyl product was detected, but the production of a small amount of monovinyl product suggested the K(m) value for coproporphyrinogen-III did not change significantly compared to the wild-type enzyme. Upon mutation of Arg262 to alanine, CPO was again a poor catalyst for the production of a divinyl product, with a catalytic efficiency <0.01% compared to wild-type, including a 15-fold higher K(m) for coproporphyrinogen-III. The efficiency of divinyl product formation for mutant enzyme Arg401Ala was approximately 3% compared to wild-type CPO, with a threefold increase in the K(m) value for coproporphyrinogen-III. These data suggest Asp400, Arg262, and Arg401 are active site amino acids critical for substrate binding and/or catalysis. Possible roles for arginine 262 and 401 include coordination of carboxylate groups of coproporphyrinogen-III, while aspartate 400 may initiate deprotonation of substrate, resulting in an oxidative decarboxylation.
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Affiliation(s)
- Jason R Stephenson
- Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, USA
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Fan J, Liu Q, Hao Q, Teng M, Niu L. Crystal structure of uroporphyrinogen decarboxylase from Bacillus subtilis. J Bacteriol 2006; 189:3573-80. [PMID: 17122346 PMCID: PMC1855892 DOI: 10.1128/jb.01083-06] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Uroporphyrinogen decarboxylase (UROD) is a branch point enzyme in the biosynthesis of the tetrapyrroles. It catalyzes the decarboxylation of four acetate groups of uroporphyrinogen III to yield coproporphyrinogen III, leading to heme and chlorophyll biosynthesis. UROD is a special type of nonoxidative decarboxylase, since no cofactor is essential for catalysis. In this work, the first crystal structure of a bacterial UROD, Bacillus subtilis UROD (UROD(Bs)), has been determined at a 2.3 A resolution. The biological unit of UROD(Bs) was determined by dynamic light scattering measurements to be a homodimer in solution. There are four molecules in the crystallographic asymmetric unit, corresponding to two homodimers. Structural comparison of UROD(Bs) with eukaryotic URODs reveals a variation of two loops, which possibly affect the binding of substrates and release of products. Structural comparison with the human UROD-coproporphyrinogen III complex discloses a similar active cleft, with five invariant polar residues (Arg29, Arg33, Asp78, Tyr154, and His322) and three invariant hydrophobic residues (Ile79, Phe144, and Phe207), in UROD(Bs). Among them, Asp78 may interact with the pyrrole NH groups of the substrate, and Arg29 is a candidate for positioning the acetate groups of the substrate. Both residues may also play catalytic roles.
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Affiliation(s)
- Jun Fan
- Hefei National laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science & Technology of China, Hefei Anhui, 230027, China
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Ajioka RS, Phillips JD, Kushner JP. Biosynthesis of heme in mammals. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:723-36. [PMID: 16839620 DOI: 10.1016/j.bbamcr.2006.05.005] [Citation(s) in RCA: 341] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2006] [Revised: 05/10/2006] [Accepted: 05/11/2006] [Indexed: 11/30/2022]
Abstract
Most iron in mammalian systems is routed to mitochondria to serve as a substrate for ferrochelatase. Ferrochelatase inserts iron into protoporphyrin IX to form heme which is incorporated into hemoglobin and cytochromes, the dominant hemoproteins in mammals. Tissue-specific regulatory features characterize the heme biosynthetic pathway. In erythroid cells, regulation is mediated by erythroid-specific transcription factors and the availability of iron as Fe/S clusters. In non-erythroid cells the pathway is regulated by heme-mediated feedback inhibition. All of the enzymes in the heme biosynthetic pathway have been crystallized and the crystal structures have permitted detailed analyses of enzyme mechanisms. All of the genes encoding the heme biosynthetic enzymes have been cloned and mutations of these genes are responsible for a group of human disorders designated the porphyrias and for X-linked sideroblastic anemia. The biochemistry, structural biology and the mechanisms of tissue-specific regulation are presented in this review along with the key features of the porphyric disorders.
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Affiliation(s)
- Richard S Ajioka
- Department of Internal Medicine, Division of Hematology, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
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49
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Andreeva A, Murzin AG. Evolution of protein fold in the presence of functional constraints. Curr Opin Struct Biol 2006; 16:399-408. [PMID: 16650981 DOI: 10.1016/j.sbi.2006.04.003] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2006] [Revised: 03/28/2006] [Accepted: 04/21/2006] [Indexed: 11/24/2022]
Abstract
The functional requirement to form and maintain the active site structure probably exerts a strong selective pressure on a protein to adopt just one stable and evolutionarily conserved fold. Nonetheless, new evidence suggests the likelihood of protein fold being neither physically nor biologically invariant. Alternative folds discovered in several proteins are composed of constant and variable parts. The latter display context-dependent conformations and a tendency to form new oligomeric interfaces. In turn, oligomerisation mediates fold evolution without loss of protein function. Gene duplication breaks down homo-oligomeric symmetry and relieves the pressure to maintain the local architecture of redundant active sites; this can lead to further structural changes.
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Affiliation(s)
- Antonina Andreeva
- MRC Centre for Protein Engineering, Hills Road, Cambridge CB2 2QH, UK
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