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Ghebreamlak S, Stoian SA, Lees NS, Cronin B, Smith F, Ross MO, Telser J, Hoffman BM, Duin EC. The Active-Site [4Fe-4S] Cluster in the Isoprenoid Biosynthesis Enzyme IspH Adopts Unexpected Redox States during Ligand Binding and Catalysis. J Am Chem Soc 2024; 146:3926-3942. [PMID: 38291562 DOI: 10.1021/jacs.3c11674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
(E)-4-Hydroxy-3-methylbut-2-enyl diphosphate reductase, or IspH (formerly known as LytB), catalyzes the terminal step of the bacterial methylerythritol phosphate (MEP) pathway for isoprene synthesis. This step converts (E)-4-hydroxy-3-methylbut-2-enyl diphosphate (HMBPP) into one of two possible isomeric products, either isopentenyl diphosphate (IPP) or dimethylallyl diphosphate (DMAPP). This reaction involves the removal of the C4 hydroxyl group of HMBPP and addition of two electrons. IspH contains a [4Fe-4S] cluster in its active site, and multiple cluster-based paramagnetic species of uncertain redox and ligation states can be detected after incubation with reductant, addition of a ligand, or during catalysis. To characterize the clusters in these species, 57Fe-labeled samples of IspH were prepared and studied by electron paramagnetic resonance (EPR), 57Fe electron-nuclear double resonance (ENDOR), and Mössbauer spectroscopies. Notably, this ENDOR study provides a rarely reported, complete determination of the 57Fe hyperfine tensors for all four Fe ions in a [4Fe-4S] cluster. The resting state of the enzyme (Ox) has a diamagnetic [4Fe-4S]2+ cluster. Reduction generates [4Fe-4S]+ (Red) with both S = 1/2 and S = 3/2 spin ground states. When the reduced enzyme is incubated with substrate, a transient paramagnetic reaction intermediate is detected (Int) which is thought to contain a cluster-bound substrate-derived species. The EPR properties of Int are indicative of a 3+ iron-sulfur cluster oxidation state, and the Mössbauer spectra presented here confirm this. Incubation of reduced enzyme with the product IPP induced yet another paramagnetic [4Fe-4S]+ species (Red+P) with S = 1/2. However, the g-tensor of this state is commonly associated with a 3+ oxidation state, while Mössbauer parameters show features typical for 2+ clusters. Implications of these complicated results are discussed.
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Affiliation(s)
- Selamawit Ghebreamlak
- Department of Chemistry and Biochemistry, Auburn University, 179 Chemistry Building, Auburn, Alabama 36849, United States
| | - Sebastian A Stoian
- Department of Chemistry, University of Idaho, 875 Perimeter Drive, MS 2343 Moscow, Idaho 83844, United States
| | - Nicholas S Lees
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Bryan Cronin
- Department of Chemistry and Biochemistry, Auburn University, 179 Chemistry Building, Auburn, Alabama 36849, United States
| | - Forrest Smith
- Department of Drug Discovery & Development, Auburn University, 4306 Walker Building, Auburn, Alabama 36849, United States
| | - Matthew O Ross
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Joshua Telser
- Department of Biological, Chemical and Physical Sciences, Roosevelt University, 430 S. Michigan Avenue, Chicago, Illinois 60605, United States
| | - Brian M Hoffman
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Evert C Duin
- Department of Chemistry and Biochemistry, Auburn University, 179 Chemistry Building, Auburn, Alabama 36849, United States
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Brown AC, Suess DLM. Valence Localization in Alkyne and Alkene Adducts of Synthetic [Fe 4S 4] + Clusters. Inorg Chem 2023; 62:1911-1918. [PMID: 35704768 PMCID: PMC9751231 DOI: 10.1021/acs.inorgchem.2c01353] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Reported herein are alkyne and alkene adducts of synthetic [Fe4S4]+ clusters that model intermediates and inhibitor-bound states in enzymes involved in isoprenoid biosynthesis. Treatment of the N-heterocyclic carbene-ligated cluster [(IMes)3Fe4S4(OEt2)][BArF4] (IMes = 1,3-dimesitylimidazol-2-ylidene; [BArF4]- = tetrakis(3,5-bis(trifluoromethyl)phenyl)borate) with phenylacetylene (PhCCH) or cis-cyclooctene (COE) results in displacement of the Et2O ligand to yield the corresponding π complexes, [(IMes)3Fe4S4(PhCCH)][BArF4] and [(IMes)3Fe4S4(COE)][BArF4]. EPR spectroscopic analysis demonstrates that both clusters are doublets with giso > 2 and thus are spectroscopically faithful models of the analogous species characterized in the isoprenoid biosynthetic enzymes IspG and IspH. Structural and Mössbauer spectroscopic analysis reveals that both complexes are best described as [Fe4S4]+ clusters in which the unique Fe site engages in modest back-bonding to the π-acidic ligand. Paramagnetic NMR studies show that, even at room temperature, the alkyne/alkene-bound Fe centers harbor minority spin and therefore adopt an Fe2+ valence. We propose that such valence localization could likewise occur in Fe-S enzymes that interact with π-acidic molecules.
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3
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Herrscher V, Witjaksono C, Buchotte M, Ferret C, Massicot F, Vasse J, Borel F, Behr J, Seemann M. Irreversible Inhibition of IspG, a Target for the Development of New Antimicrobials, by a 2‐Vinyl Analogue of its MEcPP Substrate. Chemistry 2022; 28:e202200241. [DOI: 10.1002/chem.202200241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Indexed: 11/08/2022]
Affiliation(s)
- Vivien Herrscher
- Univ. Reims Champagne-Ardenne ICMR, CNRS UMR 7312 51687 Reims Cedex 2 France
| | - Clea Witjaksono
- Equipe Chimie Biologique et Applications Thérapeutiques Institut de Chimie de Strasbourg UMR 7177 Université de Strasbourg/CNRS 4, rue Blaise Pascal 67070 Strasbourg France
| | - Marie Buchotte
- Univ. Reims Champagne-Ardenne ICMR, CNRS UMR 7312 51687 Reims Cedex 2 France
| | - Claire Ferret
- Equipe Chimie Biologique et Applications Thérapeutiques Institut de Chimie de Strasbourg UMR 7177 Université de Strasbourg/CNRS 4, rue Blaise Pascal 67070 Strasbourg France
| | - Fabien Massicot
- Univ. Reims Champagne-Ardenne ICMR, CNRS UMR 7312 51687 Reims Cedex 2 France
| | - Jean‐Luc Vasse
- Univ. Reims Champagne-Ardenne ICMR, CNRS UMR 7312 51687 Reims Cedex 2 France
| | - Franck Borel
- Univ. Grenoble Alpes, CEA, CNRS, IBS 38000 Grenoble France
| | - Jean‐Bernard Behr
- Univ. Reims Champagne-Ardenne ICMR, CNRS UMR 7312 51687 Reims Cedex 2 France
| | - Myriam Seemann
- Equipe Chimie Biologique et Applications Thérapeutiques Institut de Chimie de Strasbourg UMR 7177 Université de Strasbourg/CNRS 4, rue Blaise Pascal 67070 Strasbourg France
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Rekittke I, Warkentin E, Jomaa H, Ermler U. Structure of the GcpE-HMBPP complex from Thermus thermophilius. Biochem Biophys Res Commun 2015; 458:246-50. [DOI: 10.1016/j.bbrc.2015.01.088] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 01/19/2015] [Indexed: 11/28/2022]
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5
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Cutsail GE, Telser J, Hoffman BM. Advanced paramagnetic resonance spectroscopies of iron-sulfur proteins: Electron nuclear double resonance (ENDOR) and electron spin echo envelope modulation (ESEEM). BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:1370-94. [PMID: 25686535 DOI: 10.1016/j.bbamcr.2015.01.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 01/29/2015] [Accepted: 01/29/2015] [Indexed: 12/20/2022]
Abstract
The advanced electron paramagnetic resonance (EPR) techniques, electron nuclear double resonance (ENDOR) and electron spin echo envelope modulation (ESEEM) spectroscopies, provide unique insights into the structure, coordination chemistry, and biochemical mechanism of nature's widely distributed iron-sulfur cluster (FeS) proteins. This review describes the ENDOR and ESEEM techniques and then provides a series of case studies on their application to a wide variety of FeS proteins including ferredoxins, nitrogenase, and radical SAM enzymes. This article is part of a Special Issue entitled: Fe/S proteins: Analysis, structure, function, biogenesis and diseases.
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Affiliation(s)
- George E Cutsail
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Joshua Telser
- Department of Biological, Chemical and Physical Sciences, Roosevelt University, Chicago, IL 60605, USA
| | - Brian M Hoffman
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.
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Wang W, Oldfield E. Biometallorganische Chemie mit IspG und IspH: Struktur, Funktion und Hemmung der an der Isoprenoid-Biosynthese beteiligten [Fe 4S 4]-Proteine. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201306712] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Wang W, Oldfield E. Bioorganometallic chemistry with IspG and IspH: structure, function, and inhibition of the [Fe(4)S(4)] proteins involved in isoprenoid biosynthesis. Angew Chem Int Ed Engl 2014; 53:4294-310. [PMID: 24481599 DOI: 10.1002/anie.201306712] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Indexed: 11/12/2022]
Abstract
Enzymes of the methylerythritol phosphate pathway of isoprenoid biosynthesis are attractive anti-infective drug targets. The last two enzymes of this pathway, IspG and IspH, are [Fe4 S4 ] proteins that are not produced by humans and catalyze 2 H(+) / 2 e(-) reductions with novel mechanisms. In this Review, we summarize recent advances in structural, mechanistic, and inhibitory studies of these two enzymes. In particular, mechanistic proposals involving bioorganometallic intermediates are presented, and compared with other mechanistic possibilities. In addition, inhibitors based on substrate analogues as well as developed by rational design and compound-library screening, are discussed. The results presented support bioorganometallic catalytic mechanisms for IspG and IspH, and open up new routes to anti-infective drug design targeting [Fe4 S4 ] clusters in proteins.
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Affiliation(s)
- Weixue Wang
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (USA)
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8
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Zhao L, Chang WC, Xiao Y, Liu HW, Liu P. Methylerythritol phosphate pathway of isoprenoid biosynthesis. Annu Rev Biochem 2013; 82:497-530. [PMID: 23746261 DOI: 10.1146/annurev-biochem-052010-100934] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Isoprenoids are a class of natural products with more than 55,000 members. All isoprenoids are constructed from two precursors, isopentenyl diphosphate and its isomer dimethylallyl diphosphate. Two of the most important discoveries in isoprenoid biosynthetic studies in recent years are the elucidation of a second isoprenoid biosynthetic pathway [the methylerythritol phosphate (MEP) pathway] and a modified mevalonic acid (MVA) pathway. In this review, we summarize mechanistic insights on the MEP pathway enzymes. Because many isoprenoids have important biological activities, the need to produce them in sufficient quantities for downstream research efforts or commercial application is apparent. Recent advances in both MVA and MEP pathway-based synthetic biology are also illustrated by reviewing the landmark work of artemisinic acid and taxadien-5α-ol production through microbial fermentations.
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Affiliation(s)
- Lishan Zhao
- Amyris, Inc., Emeryville, California 94608, USA.
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9
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Structure of the GcpE (IspG)-MEcPP complex from Thermus thermophilus. FEBS Lett 2012; 586:3452-7. [DOI: 10.1016/j.febslet.2012.07.070] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 07/24/2012] [Accepted: 07/27/2012] [Indexed: 11/22/2022]
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10
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Wang W, Wang K, Span I, Jauch J, Bacher A, Groll M, Oldfield E. Are free radicals involved in IspH catalysis? An EPR and crystallographic investigation. J Am Chem Soc 2012; 134:11225-34. [PMID: 22687151 DOI: 10.1021/ja303445z] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The [4Fe-4S] protein IspH in the methylerythritol phosphate isoprenoid biosynthesis pathway is an important anti-infective drug target, but its mechanism of action is still the subject of debate. Here, by using electron paramagnetic resonance (EPR) spectroscopy and (2)H, (17)O, and (57)Fe isotopic labeling, we have characterized and assigned two key reaction intermediates in IspH catalysis. The results are consistent with the bioorganometallic mechanism proposed earlier, and the mechanism is proposed to have similarities to that of ferredoxin, thioredoxin reductase, in that one electron is transferred to the [4Fe-4S](2+) cluster, which then performs a formal two-electron reduction of its substrate, generating an oxidized high potential iron-sulfur protein (HiPIP)-like intermediate. The two paramagnetic reaction intermediates observed correspond to the two intermediates proposed in the bioorganometallic mechanism: the early π-complex in which the substrate's 3-CH(2)OH group has rotated away from the reduced iron-sulfur cluster, and the next, η(3)-allyl complex formed after dehydroxylation. No free radical intermediates are observed, and the two paramagnetic intermediates observed do not fit in a Birch reduction-like or ferraoxetane mechanism. Additionally, we show by using EPR spectroscopy and X-ray crystallography that two substrate analogues (4 and 5) follow the same reaction mechanism.
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Affiliation(s)
- Weixue Wang
- Center for Biophysics and Computational Biology, 607 South Mathews Avenue, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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11
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Structure, function and inhibition of the two- and three-domain 4Fe-4S IspG proteins. Proc Natl Acad Sci U S A 2012; 109:8558-63. [PMID: 22586085 DOI: 10.1073/pnas.1121107109] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
IspG is a 4Fe4S protein involved in isoprenoid biosynthesis. Most bacterial IspGs contain two domains: a TIM barrel (A) and a 4Fe4S domain (B), but in plants and malaria parasites, there is a large insert domain (A*) whose structure and function are unknown. We show that bacterial IspGs function in solution as (AB)(2) dimers and that mutations in either both A or both B domains block activity. Chimeras harboring an A-mutation in one chain and a B-mutation in the other have 50% of the activity seen in wild-type protein, because there is still one catalytically active AB domain. However, a plant IspG functions as an AA*B monomer. We propose, using computational modeling and electron microscopy, that the A* insert domain has a TIM barrel structure that interacts with the A domain. This structural arrangement enables the A and B domains to interact in a "cup and ball" manner during catalysis, just as in the bacterial systems. EPR/HYSCORE spectra of reaction intermediate, product, and inhibitor ligands bound to both two and three domain proteins are identical, indicating the same local electronic structure, and computational docking indicates these ligands bridge both A and B domains. Overall, the results are of broad general interest because they indicate the insert domain in three-domain IspGs is a second TIM barrel that plays a structural role and that the pattern of inhibition of both two and three domain proteins are the same, results that can be expected to be of use in drug design.
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12
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Oldfield E, Lin FY. Terpene biosynthesis: modularity rules. Angew Chem Int Ed Engl 2011; 51:1124-37. [PMID: 22105807 DOI: 10.1002/anie.201103110] [Citation(s) in RCA: 244] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Indexed: 01/10/2023]
Abstract
Terpenes are the largest class of small-molecule natural products on earth, and the most abundant by mass. Here, we summarize recent developments in elucidating the structure and function of the proteins involved in their biosynthesis. There are six main building blocks or modules (α, β, γ, δ, ε, and ζ) that make up the structures of these enzymes: the αα and αδ head-to-tail trans-prenyl transferases that produce trans-isoprenoid diphosphates from C(5) precursors; the ε head-to-head prenyl transferases that convert these diphosphates into the tri- and tetraterpene precursors of sterols, hopanoids, and carotenoids; the βγ di- and triterpene synthases; the ζ head-to-tail cis-prenyl transferases that produce the cis-isoprenoid diphosphates involved in bacterial cell wall biosynthesis; and finally the α, αβ, and αβγ terpene synthases that produce plant terpenes, with many of these modular enzymes having originated from ancestral α and β domain proteins. We also review progress in determining the structure and function of the two 4Fe-4S reductases involved in formation of the C(5) diphosphates in many bacteria, where again, highly modular structures are found.
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Affiliation(s)
- Eric Oldfield
- Department of Chemistry and Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA.
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13
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Wang W, Wang K, Li J, Nellutla S, Smirnova TI, Oldfield E. An ENDOR and HYSCORE investigation of a reaction intermediate in IspG (GcpE) catalysis. J Am Chem Soc 2011; 133:8400-3. [PMID: 21574560 DOI: 10.1021/ja200763a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
IspG is a 4Fe-4S protein that carries out an essential reduction step in isoprenoid biosynthesis. Using electron-nuclear double resonance (ENDOR) and hyperfine sublevel correlation (HYSCORE) spectroscopies on labeled samples, we have specifically assigned the hyperfine interactions in a reaction intermediate. These results help clarify the nature of the reaction intermediate, supporting a direct interaction between the unique fourth Fe in the cluster and C2 and O3 of the ligand.
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Affiliation(s)
- Weixue Wang
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 607 South Mathews Avenue, Urbana, Illinois 61801, USA
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Xiao Y, Rooker D, You Q, Meyers CLF, Liu P. IspG-catalyzed positional isotopic exchange in methylerythritol cyclodiphosphate of the deoxyxylulose phosphate pathway: mechanistic implications. Chembiochem 2011; 12:527-30. [PMID: 22238143 DOI: 10.1002/cbic.201000716] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Indexed: 11/07/2022]
Abstract
H(2)(18)O under the bridge: Recently, the deoxyxylulose phosphate (DXP) pathway was discovered to be a second pathway supplying isoprenoid biosynthetic precursors. One of steps is an IspG-catalyzed reductive deoxygenation of methylerythritol cyclodiphosphate (MEcPP) to 4-hydroxyl-3-methyl-2-(E)-1-diphosphate (HMBPP). Using [2-(13) C,(18) O]-MEcPP, we detected the positional isotopic exchange for the bridging oxygen in MEcPP.
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Affiliation(s)
- Youli Xiao
- Department of Chemistry, Boston University, Boston, MA 02215, USA
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Rekittke I, Nonaka T, Wiesner J, Demmer U, Warkentin E, Jomaa H, Ermler U. Structure of theE-1-hydroxy-2-methyl-but-2-enyl-4-diphosphate synthase (GcpE) fromThermus thermophilus. FEBS Lett 2010; 585:447-51. [DOI: 10.1016/j.febslet.2010.12.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 12/06/2010] [Accepted: 12/08/2010] [Indexed: 10/18/2022]
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17
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Lee M, Gräwert T, Quitterer F, Rohdich F, Eppinger J, Eisenreich W, Bacher A, Groll M. Biosynthesis of isoprenoids: crystal structure of the [4Fe-4S] cluster protein IspG. J Mol Biol 2010; 404:600-10. [PMID: 20932974 DOI: 10.1016/j.jmb.2010.09.050] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2010] [Revised: 09/17/2010] [Accepted: 09/21/2010] [Indexed: 11/24/2022]
Abstract
IspG protein serves as the penultimate enzyme of the recently discovered non-mevalonate pathway for the biosynthesis of the universal isoprenoid precursors, isopentenyl diphosphate and dimethylallyl diphosphate. The enzyme catalyzes the reductive ring opening of 2C-methyl-D-erythritol 2,4-cyclodiphosphate, which affords 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate. The protein was crystallized under anaerobic conditions, and its three-dimensional structure was determined to a resolution of 2.7 Å. Each subunit of the c(2) symmetric homodimer folds into two domains connected by a short linker sequence. The N-terminal domain (N domain) is an eight-stranded β barrel that belongs to the large TIM-barrel superfamily. The C-terminal domain (C domain) consists of a β sheet that is flanked on both sides by helices. One glutamate and three cysteine residues of the C domain coordinate a [4Fe-4S] cluster. Homodimer formation involves an extended contact area (about 1100 Å(2)) between helices 8 and 9 of each respective β barrel. Moreover, each C domain contacts the N domain of the partner subunit, but the interface regions are small (about 430 Å(2)). We propose that the enzyme substrate binds to the positively charged surface area at the C-terminal pole of the β barrel. The C domain carrying the iron-sulfur cluster could then move over to form a closed conformation where the substrate is sandwiched between the N domain and the C domain. This article completes the set of three-dimensional structures of the non-mevalonate pathway enzymes, which are of specific interest as potential targets for tuberculostatic and antimalarial drugs.
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Affiliation(s)
- Matthias Lee
- Lehrstuhl für Biochemie, Center for Integrated Protein Science Munich, Department Chemie, Technische Universität München, Lichtenbergstrasse 4, D-85747 Garching, Germany
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18
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Xu W, Lees NS, Adedeji D, Wiesner J, Jomaa H, Hoffman BM, Duin EC. Paramagnetic Intermediates of (E)-4-Hydroxy-3-methylbut-2-enyl Diphosphate Synthase (GcpE/IspG) under Steady-State and Pre-Steady-State Conditions. J Am Chem Soc 2010; 132:14509-20. [DOI: 10.1021/ja101764w] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Weiya Xu
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, Department of Chemistry, Northwestern University, Evanston, Illinois 60208, and Institut für Klinische Chemie und Pathobiochemie, Universitätsklinikum Giessen und Marburg, D-Giessen, 35392 Giessen, Germany
| | - Nicholas S. Lees
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, Department of Chemistry, Northwestern University, Evanston, Illinois 60208, and Institut für Klinische Chemie und Pathobiochemie, Universitätsklinikum Giessen und Marburg, D-Giessen, 35392 Giessen, Germany
| | - Dolapo Adedeji
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, Department of Chemistry, Northwestern University, Evanston, Illinois 60208, and Institut für Klinische Chemie und Pathobiochemie, Universitätsklinikum Giessen und Marburg, D-Giessen, 35392 Giessen, Germany
| | - Jochen Wiesner
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, Department of Chemistry, Northwestern University, Evanston, Illinois 60208, and Institut für Klinische Chemie und Pathobiochemie, Universitätsklinikum Giessen und Marburg, D-Giessen, 35392 Giessen, Germany
| | - Hassan Jomaa
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, Department of Chemistry, Northwestern University, Evanston, Illinois 60208, and Institut für Klinische Chemie und Pathobiochemie, Universitätsklinikum Giessen und Marburg, D-Giessen, 35392 Giessen, Germany
| | - Brian M. Hoffman
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, Department of Chemistry, Northwestern University, Evanston, Illinois 60208, and Institut für Klinische Chemie und Pathobiochemie, Universitätsklinikum Giessen und Marburg, D-Giessen, 35392 Giessen, Germany
| | - Evert C. Duin
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, Department of Chemistry, Northwestern University, Evanston, Illinois 60208, and Institut für Klinische Chemie und Pathobiochemie, Universitätsklinikum Giessen und Marburg, D-Giessen, 35392 Giessen, Germany
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Xiao Y, Nyland RL, Meyers CLF, Liu P. Methylerythritol cyclodiphosphate (MEcPP) in deoxyxylulose phosphate pathway: synthesis from an epoxide and mechanisms. Chem Commun (Camb) 2010; 46:7220-2. [PMID: 20820543 DOI: 10.1039/c0cc02594a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this communication, we reported another unique IspG-catalyzed transformation, the production of its substrate, MEcPP, from (2R,3R)-4-hydroxy-3-methyl-2,3-epoxybutanyl diphosphate (Epoxy-HMBPP) when reductants are excluded from the reaction mixture.
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Affiliation(s)
- Youli Xiao
- Department of Chemistry, Boston University, MA 02215, USA
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Wang W, Li J, Wang K, Huang C, Zhang Y, Oldfield E. Organometallic mechanism of action and inhibition of the 4Fe-4S isoprenoid biosynthesis protein GcpE (IspG). Proc Natl Acad Sci U S A 2010; 107:11189-93. [PMID: 20534554 PMCID: PMC2895101 DOI: 10.1073/pnas.1000264107] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We report the results of a series of chemical, EPR, ENDOR, and HYSCORE spectroscopic investigations of the mechanism of action (and inhibition) of GcpE, E-1-hydroxy-2-methyl-but-2-enyl-4-diphosphate (HMBPP) synthase, also known as IspG, an Fe(4)S(4) cluster-containing protein. We find that the epoxide of HMBPP when reduced by GcpE generates the same transient EPR species as observed on addition of the substrate, 2-C-methyl-D-erythritol-2, 4-cyclo-diphosphate. ENDOR and HYSCORE spectra of these transient species (using (2)H, (13)C and (17)O labeled samples) indicate formation of an Fe-C-H containing organometallic intermediate, most likely a ferraoxetane. This is then rapidly reduced to a ferracyclopropane in which the HMBPP product forms an eta(2)-alkenyl pi- (or pi/sigma) complex with the 4th Fe in the Fe(4)S(4) cluster, and a similar "metallacycle" also forms between isopentenyl diphosphate (IPP) and GcpE. Based on this metallacycle concept, we show that an alkyne (propargyl) diphosphate is a good (K(i) approximately 300 nM) GcpE inhibitor, and supported again by EPR and ENDOR results (a (13)C hyperfine coupling of approximately 7 MHz), as well as literature precedent, we propose that the alkyne forms another pi/sigma metallacycle, an eta(2)-alkynyl, or ferracyclopropene. Overall, the results are of broad general interest because they provide new mechanistic insights into GcpE catalysis and inhibition, with organometallic bond formation playing, in both cases, a key role.
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Affiliation(s)
- Weixue Wang
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 607 South Mathews Avenue, Urbana, IL 61801
| | - Jikun Li
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 607 South Mathews Avenue, Urbana, IL 61801
| | - Ke Wang
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801; and
| | - Cancan Huang
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 607 South Mathews Avenue, Urbana, IL 61801
| | - Yong Zhang
- Department of Chemistry and Biochemistry, University of Southern Mississippi, 118 College Drive #5043, Hattiesburg, MS 39406
| | - Eric Oldfield
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 607 South Mathews Avenue, Urbana, IL 61801
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801; and
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Xiao Y, Zahariou G, Sanakis Y, Liu P. IspG enzyme activity in the deoxyxylulose phosphate pathway: roles of the iron-sulfur cluster. Biochemistry 2009; 48:10483-5. [PMID: 19821611 DOI: 10.1021/bi901519q] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
IspG is a [4Fe-4S] cluster-containing protein, and the [4Fe-4S](+) species is proposed to be the catalytically relevant species. However, attempts reported in the literature failed to detect the [4Fe-4S](+) species. In this study, using a potent reduction system, we have successfully detected the [4Fe-4S](+) species with X-band EPR spectroscopy. In addition, we have improved the Escherichia coli IspG activity to 550 nmol min(-1) mg(-1), which is approximately 20-fold greater than that of the NADPH-Fpr-FldA system in the literature.
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Affiliation(s)
- Youli Xiao
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA
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From molecular fossils of bacterial hopanoids to the formation of isoprene units: discovery and elucidation of the methylerythritol phosphate pathway. Lipids 2008; 43:1095-107. [PMID: 19011917 DOI: 10.1007/s11745-008-3261-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Accepted: 10/21/2008] [Indexed: 10/21/2022]
Abstract
Investigations on the biosynthesis of bacterial triterpenoids of the hopane series led to the unexpected discovery of an alternative mevalonate independent pathway for the formation of isoprene units. Methylerythritol phosphate, already presenting the C5 branched isoprene skeleton, is the key intermediate. This pathway was independently characterized in ginkgo embryos for the formation of diterpenoids. It is present in most bacteria and in the plastids of all organisms belonging to phototrophic phyla. The key steps of the discovery and elucidation of this metabolic route are presented in this review.
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Lagisetti C, Urbansky M, Coates RM. The dioxanone approach to (2S,3R)-2-C-methylerythritol 4-phosphate and 2,4-cyclodiphosphate, and various MEP analogues. J Org Chem 2007; 72:9886-95. [PMID: 18020362 DOI: 10.1021/jo0711900] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Efficient syntheses of the non-mevalonate pathway intermediates 2-C-methylerythritol 4-phosphate (MEP) and 2-C-methylerythritol 2,4-cyclodiphosphate (ME-2,4-cycloPP), as well as the parent tetrol 2-C-methylerythritol, in enantiopure form from (2S,4R)-cis-2-phenyl-4-tert-butyldimethylsilyloxy-1,3-dioxan-5-one are reported. The 2S configuration of the C-methyl group was installed by highly axial-face selective addition of CH3MgBr (20:1) to the chiral dioxanone carbonyl group. Primary selective mono-phosphorylation and 2,4-bis-phosphorylation, followed by desilation and hydrogenolysis to the free mono- and diphosphates, and, in the latter case, cyclization to form the eight-membered phosphoryl anhydride, afforded MEP and ME-2,4-cycloPP in good yields. The C2 epimeric analogues, 2-C-methylthreitol and its 4-phosphate, were accessed by LiAlH4 reduction of the cis,cis epoxide of (2S,4R)-4-tert-butyldimethylsilyloxymethyl-5-methylene-2-phenyl-1,3-dioxane, primary-selective phosphorylation, and cleavage of the silyl, benzylidene, and benzyl protecting groups. Regioselective cleavage of the acetal ring of 1,3-benzylidene 2-C-methylerythritol silyl ether by ozonolysis afforded a 1,2,3-triol 3-monobenzoate intermediate that was converted to the novel amino sugar, 1-amino-1-deoxy-2-C-methylerythritol.
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Affiliation(s)
- Chandraiah Lagisetti
- Department of Chemistry, University of Illinois, 600 South Mathews Avenue, Urbana, Illinois 61801, USA
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