1
|
Muñoz-Vargas MA, López-Jaramillo J, González-Gordo S, Paradela A, Palma JM, Corpas FJ. H 2S-Generating Cytosolic L-Cysteine Desulfhydrase and Mitochondrial D-Cysteine Desulfhydrase from Sweet Pepper ( Capsicum annuum L.) Are Regulated During Fruit Ripening and by Nitric Oxide. Antioxid Redox Signal 2023; 39:2-18. [PMID: 36950799 PMCID: PMC10585658 DOI: 10.1089/ars.2022.0222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 02/27/2023] [Accepted: 03/13/2023] [Indexed: 03/24/2023]
Abstract
Aims: Pepper fruit is a horticultural product worldwide consumed that has great nutritional and economic relevance. Besides the phenotypical changes that undergo pepper fruit during ripening, there are many associated modifications at transcriptomic, proteomic, biochemical, and metabolic levels. Nitric oxide (NO) and hydrogen sulfide (H2S) are recognized signal molecules that can exert regulatory functions in diverse plant processes. This study aims at analyzing the interrelationship between NO and H2S during fruit ripening. Results: Our data indicate that the H2S-generating cytosolic L-cysteine desulfhydrase (LCD) and the mitochondrial D-cysteine desulfhydrase (DCD) activities are downregulated during ripening but this effect was reverted after NO treatment of fruits. Innovation and Conclusion: Using as a model the non-climacteric pepper fruits at different ripening stages and under an NO-enriched atmosphere, the activity of the H2S-generating LCD and DCD was analyzed. LCD and DCD activities were downregulated during ripening, but this effect was reverted after NO treatment of fruits. The analysis of LCD activity by non-denaturing polyacrylamide gel electrophoresis (PAGE) allowed identifying three isozymes designated CaLCD I to CaLCD III, which were differentially modulated by NO and strictly dependent on pyridoxal 5'-phosphate (PLP). In vitro analyses of green fruit samples in the presence of different compounds including NO donors, peroxynitrite (ONOO-), and reducing agents such as reduced glutathione (GSH) and L-cysteine (L-Cys) triggered an almost 100% inhibition of CaLCD II and CaLCD III. This redox adaptation process of both enzymes could be cataloged as a hormesis phenomenon. The protein tyrosine (Tyr) nitration (an NO-promoted post-translational modification) of the recombinant LCD was corroborated by immunoblot and by mass spectrometry (MS) analyses. Among the 11 Tyr residues present in this enzyme, MS of the recombinant LCD enabled us to identify that Tyr82 and Tyr254 were nitrated by ONOO-, this occurring near the active center on the enzyme, where His237 and Lys260 together with the cofactor PLP are involved. These data support the relationship between NO and H2S during pepper fruit ripening, since LCD and DCD are regulated by NO during this physiological event, and this could also be extrapolated to other plant species.
Collapse
Affiliation(s)
- María A. Muñoz-Vargas
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture. Estación Experimental del Zaidín (Spanish National Research Council, CSIC), Granada, Spain
| | - Javier López-Jaramillo
- Instituto de Biotecnología, Department of Organic Chemistry, University of Granada, Granada, Spain
| | - Salvador González-Gordo
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture. Estación Experimental del Zaidín (Spanish National Research Council, CSIC), Granada, Spain
| | - Alberto Paradela
- Proteomics Core Facility, Centro Nacional de Biotecnología, CSIC, Madrid, Spain
| | - José M. Palma
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture. Estación Experimental del Zaidín (Spanish National Research Council, CSIC), Granada, Spain
| | - Francisco J. Corpas
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture. Estación Experimental del Zaidín (Spanish National Research Council, CSIC), Granada, Spain
| |
Collapse
|
2
|
Hudspeth J, Boncella AE, Sabo ET, Andrews T, Boyd JM, Morrison CN. Structural and Biochemical Characterization of Staphylococcus aureus Cysteine Desulfurase Complex SufSU. ACS OMEGA 2022; 7:44124-44133. [PMID: 36506149 PMCID: PMC9730764 DOI: 10.1021/acsomega.2c05576] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 11/09/2022] [Indexed: 06/01/2023]
Abstract
In this work, we provide the first in vitro characterization of two essential proteins from Staphylococcus aureus (S. aureus) involved in iron-sulfur (Fe-S) cluster biogenesis: the cysteine desulfurase SufS and the sulfurtransferase SufU. Together, these proteins form the transient SufSU complex and execute the first stage of Fe-S cluster biogenesis in the SUF-like pathway in Gram-positive bacteria. The proteins involved in the SUF-like pathway, such as SufS and SufU, are essential in Gram-positive bacteria since these bacteria tend to lack redundant Fe-S cluster biogenesis pathways. Most previous work characterizing the SUF-like pathway has focused on Bacillus subtilis (B. subtilis). We focus on the SUF-like pathway in S. aureus because of its potential to serve as a therapeutic target to treat S. aureus infections. Herein, we characterize S. aureus SufS (SaSufS) by X-ray crystallography and UV-vis spectroscopy, and we characterize S. aureus SufU (SaSufU) by a zinc binding fluorescence assay and small-angle X-ray scattering. We show that SaSufS is a type II cysteine desulfurase and that SaSufU is a Zn2+-containing sulfurtransferase. Additionally, we evaluated the cysteine desulfurase activity of the SaSufSU complex and compared its activity to that of B. subtilis SufSU. Subsequent cross-species activity analysis reveals a surprising result: SaSufS is significantly less stimulated by SufU than BsSufS. Our results set a basis for further characterization of SaSufSU as well as the development of new therapeutic strategies for treating infections caused by S. aureus by inhibiting the SUF-like pathway.
Collapse
Affiliation(s)
- Jesse
D. Hudspeth
- Department
of Chemistry, Colorado School of Mines, 1500 Illinois St, Golden, Colorado 80401, United States
| | - Amy E. Boncella
- Department
of Chemistry, Colorado School of Mines, 1500 Illinois St, Golden, Colorado 80401, United States
| | - Emily T. Sabo
- Department
of Chemistry, Colorado School of Mines, 1500 Illinois St, Golden, Colorado 80401, United States
| | - Taylor Andrews
- Department
of Biochemistry and Microbiology, Rutgers
University, 76 Lipman Dr., New Brunswick, New Jersey 08901, United States
| | - Jeffrey M. Boyd
- Department
of Biochemistry and Microbiology, Rutgers
University, 76 Lipman Dr., New Brunswick, New Jersey 08901, United States
| | - Christine N. Morrison
- Department
of Chemistry, Colorado School of Mines, 1500 Illinois St, Golden, Colorado 80401, United States
| |
Collapse
|
3
|
Karunakaran G, Yang Y, Tremblay V, Ning Z, Martin J, Belaouad A, Figeys D, Brunzelle J, Giguere PM, Stintzi A, Couture JF. Structural analysis of Atopobium parvulum SufS cysteine desulfurase linked to Crohn's disease. FEBS Lett 2022; 596:898-909. [PMID: 35122247 DOI: 10.1002/1873-3468.14295] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 12/20/2021] [Accepted: 12/21/2021] [Indexed: 11/09/2022]
Abstract
Crohn's Disease (CD) is characterized by the chronic inflammation of the gastrointestinal tract. A dysbiotic microbiome and a defective immune system are linked to CD, where hydrogen sulfide (H2 S) microbial producers positively correlate with the severity of the disease. Atopobium parvulum is a key H2 S producer from the microbiome of CD patients. In this study, the biochemical characterization of two Atopobium parvulum cysteine desulfurases, ApSufS and ApCsdB, show that the enzymes are allosterically regulated. Structural analyses reveal that ApSufS forms a dimer with conserved characteristics observed in type II cysteine desulfurases. Four residues surrounding the active site are essential to catalyze cysteine desulfurylation, and a segment of short-chain residues grant access for substrate binding. A better understanding of ApSufS will help future avenues for CD treatment.
Collapse
Affiliation(s)
- Gapisha Karunakaran
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Shanghai Institute of Materia Medica-University of Ottawa Joint Research Centre on Systems and Personalized Pharmacology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| | - Yidai Yang
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Shanghai Institute of Materia Medica-University of Ottawa Joint Research Centre on Systems and Personalized Pharmacology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| | - Véronique Tremblay
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Shanghai Institute of Materia Medica-University of Ottawa Joint Research Centre on Systems and Personalized Pharmacology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| | - Zhibin Ning
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Shanghai Institute of Materia Medica-University of Ottawa Joint Research Centre on Systems and Personalized Pharmacology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| | - Jade Martin
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Shanghai Institute of Materia Medica-University of Ottawa Joint Research Centre on Systems and Personalized Pharmacology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| | - Amine Belaouad
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Shanghai Institute of Materia Medica-University of Ottawa Joint Research Centre on Systems and Personalized Pharmacology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| | - Daniel Figeys
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Shanghai Institute of Materia Medica-University of Ottawa Joint Research Centre on Systems and Personalized Pharmacology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| | - Joseph Brunzelle
- Feinberg School of Medicine, Department of Molecular Pharmacology and Biological Chemistry, Northwestern University, Chicago, Illinois, 60611, USA
| | - Patrick M Giguere
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| | - Alain Stintzi
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Shanghai Institute of Materia Medica-University of Ottawa Joint Research Centre on Systems and Personalized Pharmacology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| | - Jean-François Couture
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada.,Shanghai Institute of Materia Medica-University of Ottawa Joint Research Centre on Systems and Personalized Pharmacology, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, Ottawa, ON, Canada
| |
Collapse
|
4
|
Das M, Dewan A, Shee S, Singh A. The Multifaceted Bacterial Cysteine Desulfurases: From Metabolism to Pathogenesis. Antioxidants (Basel) 2021; 10:antiox10070997. [PMID: 34201508 PMCID: PMC8300815 DOI: 10.3390/antiox10070997] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/01/2021] [Accepted: 05/06/2021] [Indexed: 12/02/2022] Open
Abstract
Living cells have developed a relay system to efficiently transfer sulfur (S) from cysteine to various thio-cofactors (iron-sulfur (Fe-S) clusters, thiamine, molybdopterin, lipoic acid, and biotin) and thiolated tRNA. The presence of such a transit route involves multiple protein components that allow the flux of S to be precisely regulated as a function of environmental cues to avoid the unnecessary accumulation of toxic concentrations of soluble sulfide (S2−). The first enzyme in this relay system is cysteine desulfurase (CSD). CSD catalyzes the release of sulfane S from L-cysteine by converting it to L-alanine by forming an enzyme-linked persulfide intermediate on its conserved cysteine residue. The persulfide S is then transferred to diverse acceptor proteins for its incorporation into the thio-cofactors. The thio-cofactor binding-proteins participate in essential and diverse cellular processes, including DNA repair, respiration, intermediary metabolism, gene regulation, and redox sensing. Additionally, CSD modulates pathogenesis, antibiotic susceptibility, metabolism, and survival of several pathogenic microbes within their hosts. In this review, we aim to comprehensively illustrate the impact of CSD on bacterial core metabolic processes and its requirement to combat redox stresses and antibiotics. Targeting CSD in human pathogens can be a potential therapy for better treatment outcomes.
Collapse
|
5
|
Abstract
Iron–sulfur (Fe–S) clusters are protein cofactors of a multitude of enzymes performing essential biological functions. Specialized multi-protein machineries present in all types of organisms support their biosynthesis. These machineries encompass a scaffold protein on which Fe–S clusters are assembled and a cysteine desulfurase that provides sulfur in the form of a persulfide. The sulfide ions are produced by reductive cleavage of the persulfide, which involves specific reductase systems. Several other components are required for Fe–S biosynthesis, including frataxin, a key protein of controversial function and accessory components for insertion of Fe–S clusters in client proteins. Fe–S cluster biosynthesis is thought to rely on concerted and carefully orchestrated processes. However, the elucidation of the mechanisms of their assembly has remained a challenging task due to the biochemical versatility of iron and sulfur and the relative instability of Fe–S clusters. Nonetheless, significant progresses have been achieved in the past years, using biochemical, spectroscopic and structural approaches with reconstituted system in vitro. In this paper, we review the most recent advances on the mechanism of assembly for the founding member of the Fe–S cluster family, the [2Fe2S] cluster that is the building block of all other Fe–S clusters. The aim is to provide a survey of the mechanisms of iron and sulfur insertion in the scaffold proteins by examining how these processes are coordinated, how sulfide is produced and how the dinuclear [2Fe2S] cluster is formed, keeping in mind the question of the physiological relevance of the reconstituted systems. We also cover the latest outcomes on the functional role of the controversial frataxin protein in Fe–S cluster biosynthesis.
Collapse
|
6
|
Blahut M, Sanchez E, Fisher CE, Outten FW. Fe-S cluster biogenesis by the bacterial Suf pathway. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118829. [PMID: 32822728 DOI: 10.1016/j.bbamcr.2020.118829] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/11/2020] [Accepted: 08/11/2020] [Indexed: 01/01/2023]
Abstract
Biogenesis of iron-sulfur (FeS) clusters in an essential process in living organisms due to the critical role of FeS cluster proteins in myriad cell functions. During biogenesis of FeS clusters, multi-protein complexes are used to drive the mobilization and protection of reactive sulfur and iron intermediates, regulate assembly of various FeS clusters on an ATPase-dependent, multi-protein scaffold, and target nascent clusters to their downstream protein targets. The evolutionarily ancient sulfur formation (Suf) pathway for FeS cluster assembly is found in bacteria and archaea. In Escherichia coli, the Suf pathway functions as an emergency pathway under conditions of iron limitation or oxidative stress. In other pathogenic bacteria, such as Mycobacterium tuberculosis and Enterococcus faecalis, the Suf pathway is the sole source for FeS clusters and therefore is a potential target for the development of novel antibacterial compounds. Here we summarize the considerable progress that has been made in characterizing the first step of mobilization and protection of reactive sulfur carried out by the SufS-SufE or SufS-SufU complex, FeS cluster assembly on SufBC2D scaffold complexes, and the downstream trafficking of nascent FeS clusters to A-type carrier (ATC) proteins. Cell Biology of Metals III edited by Roland Lill and Mick Petris.
Collapse
Affiliation(s)
- Matthew Blahut
- Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208, USA
| | - Enis Sanchez
- Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208, USA
| | - Claire E Fisher
- Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208, USA
| | - F Wayne Outten
- Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208, USA.
| |
Collapse
|
7
|
Scortecci JF, Serrão VHB, Fernandes AF, Basso LG, Gutierrez RF, Araujo APU, Neto MO, Thiemann OH. Initial steps in selenocysteine biosynthesis: The interaction between selenocysteine lyase and selenophosphate synthetase. Int J Biol Macromol 2020; 156:18-26. [DOI: 10.1016/j.ijbiomac.2020.03.241] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 02/29/2020] [Accepted: 03/28/2020] [Indexed: 10/24/2022]
|
8
|
Structural Analysis of an l-Cysteine Desulfurase from an Ssp DNA Phosphorothioation System. mBio 2020; 11:mBio.00488-20. [PMID: 32345643 PMCID: PMC7188994 DOI: 10.1128/mbio.00488-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Apart from its roles in Fe-S cluster assembly, tRNA thiolation, and sulfur-containing cofactor biosynthesis, cysteine desulfurase serves as a sulfur donor in the DNA PT modification, in which a sulfur atom substitutes a nonbridging oxygen in the DNA phosphodiester backbone. The initial sulfur mobilization from l-cysteine is catalyzed by the SspA cysteine desulfurase in the SspABCD-mediated DNA PT modification system. By determining the crystal structure of SspA, the study presents the molecular mechanism that SspA employs to recognize its cysteine substrate and PLP cofactor. To overcome the long distance (8.9 Å) between the catalytic Cys314 and the cysteine substrate, a conformational change occurs to bring Cys314 to the vicinity of the substrate, allowing for nucleophilic attack. DNA phosphorothioate (PT) modification, in which the nonbridging oxygen in the sugar-phosphate backbone is substituted by sulfur, is catalyzed by DndABCDE or SspABCD in a double-stranded or single-stranded manner, respectively. In Dnd and Ssp systems, mobilization of sulfur in PT formation starts with the activation of the sulfur atom of cysteine catalyzed by the DndA and SspA cysteine desulfurases, respectively. Despite playing the same biochemical role, SspA cannot be functionally replaced by DndA, indicating its unique physiological properties. In this study, we solved the crystal structure of Vibrio cyclitrophicus SspA in complex with its natural substrate, cysteine, and cofactor, pyridoxal phosphate (PLP), at a resolution of 1.80 Å. Our solved structure revealed the molecular mechanism that SspA employs to recognize its cysteine substrate and PLP cofactor, suggesting a common binding mode shared by cysteine desulfurases. In addition, although the distance between the catalytic Cys314 and the substrate cysteine is 8.9 Å, which is too far for direct interaction, our structural modeling and biochemical analysis revealed a conformational change in the active site region toward the cysteine substrate to move them close to each other to facilitate the nucleophilic attack. Finally, the pulldown analysis showed that SspA could form a complex with SspD, an ATP pyrophosphatase, suggesting that SspD might potentially accept the activated sulfur atom directly from SspA, providing further insights into the biochemical pathway of Ssp-mediated PT modification.
Collapse
|
9
|
Puglisi R, Boeri Erba E, Pastore A. A Guide to Native Mass Spectrometry to determine complex interactomes of molecular machines. FEBS J 2020; 287:2428-2439. [PMID: 32142206 PMCID: PMC8647915 DOI: 10.1111/febs.15281] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 02/01/2020] [Accepted: 03/04/2020] [Indexed: 01/17/2023]
Abstract
Native mass spectrometry is an emerging technique in biology that gives the possibility to study noncovalently bound complexes with high sensitivity and accuracy. It thus allows the characterization of macromolecular assemblies, assessing their mass and stoichiometries and mapping the interacting surfaces. In this review, we discuss the application of native mass spectrometry to dynamic molecular machines based on multiple weak interactions. In the study of these machines, it is crucial to understand which and under which conditions various complexes form at any time point. We focus on the specific example of the iron-sulfur cluster biogenesis machine because this is an archetype of a dynamic machine that requires very specific and demanding experimental conditions, such as anaerobicity and the need of retaining the fold of marginally folded proteins. We describe the advantages, challenges and current limitations of the technique by providing examples from our own experience and suggesting possible future solutions.
Collapse
Affiliation(s)
- Rita Puglisi
- UK Dementia Research Institute at the Wohl Institute of King's College London, UK
| | - Elisabetta Boeri Erba
- Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale (IBS), Grenoble, France
| | - Annalisa Pastore
- UK Dementia Research Institute at the Wohl Institute of King's College London, UK
| |
Collapse
|
10
|
Dunkle JA, Bruno MR, Frantom PA. Structural evidence for a latch mechanism regulating access to the active site of SufS-family cysteine desulfurases. Acta Crystallogr D Struct Biol 2020; 76:291-301. [PMID: 32133993 PMCID: PMC7057215 DOI: 10.1107/s2059798320000790] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 01/22/2020] [Indexed: 11/10/2022] Open
Abstract
Cysteine serves as the sulfur source for the biosynthesis of Fe-S clusters and thio-cofactors, molecules that are required for core metabolic processes in all organisms. Therefore, cysteine desulfurases, which mobilize sulfur for its incorporation into thio-cofactors by cleaving the Cα-S bond of cysteine, are ubiquitous in nature. SufS, a type 2 cysteine desulfurase that is present in plants and microorganisms, mobilizes sulfur from cysteine to the transpersulfurase SufE to initiate Fe-S biosynthesis. Here, a 1.5 Å resolution X-ray crystal structure of the Escherichia coli SufS homodimer is reported which adopts a state in which the two monomers are rotated relative to their resting state, displacing a β-hairpin from its typical position blocking transpersulfurase access to the SufS active site. A global structure and sequence analysis of SufS family members indicates that the active-site β-hairpin is likely to require adjacent structural elements to function as a β-latch regulating access to the SufS active site.
Collapse
Affiliation(s)
- Jack A. Dunkle
- Department of Chemistry and Biochemistry, University of Alabama, 250 Hackberry Lane, Tuscaloosa, AL 35401, USA
| | - Michael R. Bruno
- Department of Chemistry and Biochemistry, University of Alabama, 250 Hackberry Lane, Tuscaloosa, AL 35401, USA
| | - Patrick A. Frantom
- Department of Chemistry and Biochemistry, University of Alabama, 250 Hackberry Lane, Tuscaloosa, AL 35401, USA
| |
Collapse
|
11
|
Blahut M, Wise CE, Bruno MR, Dong G, Makris TM, Frantom PA, Dunkle JA, Outten FW. Direct observation of intermediates in the SufS cysteine desulfurase reaction reveals functional roles of conserved active-site residues. J Biol Chem 2019; 294:12444-12458. [PMID: 31248989 DOI: 10.1074/jbc.ra119.009471] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 06/16/2019] [Indexed: 12/25/2022] Open
Abstract
Iron-sulfur (Fe-S) clusters are necessary for the proper functioning of numerous metalloproteins. Fe-S cluster (Isc) and sulfur utilization factor (Suf) pathways are the key biosynthetic routes responsible for generating these Fe-S cluster prosthetic groups in Escherichia coli Although Isc dominates under normal conditions, Suf takes over during periods of iron depletion and oxidative stress. Sulfur acquisition via these systems relies on the ability to remove sulfur from free cysteine using a cysteine desulfurase mechanism. In the Suf pathway, the dimeric SufS protein uses the cofactor pyridoxal 5'-phosphate (PLP) to abstract sulfur from free cysteine, resulting in the production of alanine and persulfide. Despite much progress, the stepwise mechanism by which this PLP-dependent enzyme operates remains unclear. Here, using rapid-mixing kinetics in conjunction with X-ray crystallography, we analyzed the pre-steady-state kinetics of this process while assigning early intermediates of the mechanism. We employed H123A and C364A SufS variants to trap Cys-aldimine and Cys-ketimine intermediates of the cysteine desulfurase reaction, enabling direct observations of these intermediates and associated conformational changes of the SufS active site. Of note, we propose that Cys-364 is essential for positioning the Cys-aldimine for Cα deprotonation, His-123 acts to protonate the Ala-enamine intermediate, and Arg-56 facilitates catalysis by hydrogen bonding with the sulfhydryl of Cys-aldimine. Our results, along with previous SufS structural findings, suggest a detailed model of the SufS-catalyzed reaction from Cys binding to C-S bond cleavage and indicate that Arg-56, His-123, and Cys-364 are critical SufS residues in this C-S bond cleavage pathway.
Collapse
Affiliation(s)
- Matthew Blahut
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
| | - Courtney E Wise
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
| | - Michael R Bruno
- Department of Chemistry and Biochemistry, University of Alabama, Tuscaloosa, Alabama 35487
| | - Guangchao Dong
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
| | - Thomas M Makris
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
| | - Patrick A Frantom
- Department of Chemistry and Biochemistry, University of Alabama, Tuscaloosa, Alabama 35487
| | - Jack A Dunkle
- Department of Chemistry and Biochemistry, University of Alabama, Tuscaloosa, Alabama 35487.
| | - F Wayne Outten
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208.
| |
Collapse
|
12
|
Wang L, Jiang S, Deng Z, Dedon PC, Chen S. DNA phosphorothioate modification-a new multi-functional epigenetic system in bacteria. FEMS Microbiol Rev 2019; 43:109-122. [PMID: 30289455 PMCID: PMC6435447 DOI: 10.1093/femsre/fuy036] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/03/2018] [Indexed: 12/20/2022] Open
Abstract
Synthetic phosphorothioate (PT) internucleotide linkages, in which a nonbridging oxygen is replaced by a sulphur atom, share similar physical and chemical properties with phosphodiesters but confer enhanced nuclease tolerance on DNA/RNA, making PTs a valuable biochemical and pharmacological tool. Interestingly, PT modification was recently found to occur naturally in bacteria in a sequence-selective and RP configuration-specific manner. This oxygen-sulphur swap is catalysed by the gene products of dndABCDE, which constitute a defence barrier with DndFGH in some bacterial strains that can distinguish and attack non-PT-modified foreign DNA, resembling DNA methylation-based restriction-modification (R-M) systems. Despite their similar defensive mechanisms, PT- and methylation-based R-M systems have evolved to target different consensus contexts in the host cell because when they share the same recognition sequences, the protective function of each can be impeded. The redox and nucleophilic properties of PT sulphur render PT modification a versatile player in the maintenance of cellular redox homeostasis, epigenetic regulation and environmental fitness. The widespread presence of dnd systems is considered a consequence of extensive horizontal gene transfer, whereas the lability of PT during oxidative stress and the susceptibility of PT to PT-dependent endonucleases provide possible explanations for the ubiquitous but sporadic distribution of PT modification in the bacterial world.
Collapse
Affiliation(s)
- Lianrong Wang
- Zhongnan Hospital, Wuhan University, 169 Donghu Road, Wuhan 430071, China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, 185 Donghu Road, Wuhan 430071, China
| | - Susu Jiang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, 185 Donghu Road, Wuhan 430071, China
| | - Zixin Deng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, 185 Donghu Road, Wuhan 430071, China
| | - Peter C Dedon
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Masschusetts Avenue, Cambridge, Massachusetts, USA
| | - Shi Chen
- Zhongnan Hospital, Wuhan University, 169 Donghu Road, Wuhan 430071, China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, 185 Donghu Road, Wuhan 430071, China
| |
Collapse
|
13
|
Pala ZR, Saxena V, Saggu GS, Mani SK, Pareek RP, Kochar SK, Kochar DK, Garg S. Functional analysis of iron-sulfur cluster biogenesis (SUF pathway) from Plasmodium vivax clinical isolates. Exp Parasitol 2019; 198:53-62. [PMID: 30721667 DOI: 10.1016/j.exppara.2019.01.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 08/29/2018] [Accepted: 01/30/2019] [Indexed: 10/27/2022]
Abstract
Iron-sulfur (Fe-S) clusters are critical metallo-cofactors required for cell function. Assembly of these cofactors is a carefully controlled process in cells to avoid toxicity from free iron and sulfide. In Plasmodium, two pathways for these Fe-S cluster biogenesis have been reported; ISC pathway in the mitochondria and SUF pathway functional in the apicoplast. Amongst these, SUF pathway is reported essential for the apicoplast maintenance and parasite survival. Many of its components have been studied from P. falciparum and P. berghei in recent years, still few queries remain to be addressed; one of them being the assembly and transfer of Fe-S clusters. In this study, using P. vivax clinical isolates, we have shown the in vitro interaction of SUF pathway proteins SufS and SufE responsible for sulfur mobilization in the apicoplast. The sulfur mobilized by the SufSE complex assembles on the scaffold protein PvSufA along with iron provided by the external source. Here, we demonstrate in vitro transfer of these labile Fe-S clusters from the scaffold protein on to an apo-protein, PvIspG (a protein involved in penultimate step of Isoprenoids biosynthesis pathway) in order to provide an insight into the interaction of different components for the biosynthesis and transfer of Fe-S clusters. Our analysis indicate that inspite of the presence of variations in pathway proteins, the overall pathway remains well conserved in the clinical isolates when compared to that reported in lab strains.
Collapse
Affiliation(s)
- Zarna Rajeshkumar Pala
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Vishal Saxena
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan, India.
| | - Gagandeep Singh Saggu
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Satish Kailasam Mani
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Rajendra Prasad Pareek
- Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Sanjay Kumar Kochar
- Department of Medicine, Sardar Patel Medical College, Bikaner, Rajasthan, India
| | - Dhanpat Kumar Kochar
- Department of Medicine, Rajasthan University of Health Sciences, Jaipur, Rajasthan, India
| | - Shilpi Garg
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan, India.
| |
Collapse
|
14
|
Dunkle JA, Bruno MR, Outten FW, Frantom PA. Structural Evidence for Dimer-Interface-Driven Regulation of the Type II Cysteine Desulfurase, SufS. Biochemistry 2019; 58:687-696. [PMID: 30571100 DOI: 10.1021/acs.biochem.8b01122] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
SufS is a type II cysteine desulfurase and acts as the initial step in the Suf Fe-S cluster assembly pathway. In Escherichia coli, this pathway is utilized under conditions of oxidative stress and is resistant to reactive oxygen species. Mechanistically, this means SufS must shift between protecting a covalent persulfide intermediate and making it available for transfer to the next protein partner in the pathway, SufE. Here, we report five X-ray crystal structures of SufS including a new structure of SufS containing an inward-facing persulfide intermediate on C364. Additional structures of SufS variants with substitutions at the dimer interface show changes in dimer geometry and suggest a conserved β-hairpin structure plays a role in mediating interactions with SufE. These new structures, along with previous HDX-MS and biochemical data, identify an interaction network capable of communication between active-sites of the SufS dimer coordinating the shift between desulfurase and transpersulfurase activities.
Collapse
Affiliation(s)
- Jack A Dunkle
- Department of Chemistry & Biochemistry , The University of Alabama , Tuscaloosa , Alabama 35487 , United States
| | - Michael R Bruno
- Department of Chemistry & Biochemistry , The University of Alabama , Tuscaloosa , Alabama 35487 , United States
| | - F Wayne Outten
- Department of Chemistry & Biochemistry , The University of South Carolina , Columbia , South Carolina 29208 , United States
| | - Patrick A Frantom
- Department of Chemistry & Biochemistry , The University of Alabama , Tuscaloosa , Alabama 35487 , United States
| |
Collapse
|
15
|
Tobe R, Mihara H. Delivery of selenium to selenophosphate synthetase for selenoprotein biosynthesis. Biochim Biophys Acta Gen Subj 2018; 1862:2433-2440. [PMID: 29859962 DOI: 10.1016/j.bbagen.2018.05.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 05/28/2018] [Accepted: 05/29/2018] [Indexed: 11/16/2022]
Abstract
BACKGROUND Selenophosphate, the key selenium donor for the synthesis of selenoprotein and selenium-modified tRNA, is produced by selenophosphate synthetase (SPS) from ATP, selenide, and H2O. Although free selenide can be used as the in vitro selenium substrate for selenophosphate synthesis, the precise physiological system that donates in vivo selenium substrate to SPS has not yet been characterized completely. SCOPE OF REVIEW In this review, we discuss selenium metabolism with respect to the delivery of selenium to SPS in selenoprotein biosynthesis. MAJOR CONCLUSIONS Glutathione, selenocysteine lyase, cysteine desulfurase, and selenium-binding proteins are the candidates of selenium delivery system to SPS. The thioredoxin system is also implicated in the selenium delivery to SPS in Escherichia coli. GENERAL SIGNIFICANCE Selenium delivered via a protein-bound selenopersulfide intermediate emerges as a central element not only in achieving specific selenoprotein biosynthesis but also in preventing the occurrence of toxic free selenide in the cell. This article is part of a Special Issue entitled "Selenium research in biochemistry and biophysics - 200 year anniversary".
Collapse
Affiliation(s)
- Ryuta Tobe
- Department of Biotechnology, College of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan
| | - Hisaaki Mihara
- Department of Biotechnology, College of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan.
| |
Collapse
|
16
|
Wang Y, Liu Q, Zhou H, Chen X. Expression, purification and function of cysteine desulfurase from Sulfobacillus acidophilus TPY isolated from deep-sea hydrothermal vent. 3 Biotech 2017; 7:360. [PMID: 28979833 DOI: 10.1007/s13205-017-0995-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 09/23/2017] [Indexed: 11/25/2022] Open
Abstract
The cysteine desulfurase (SufS) gene of Sulfobacillus acidophilus TPY, a Gram-positive bacterium isolated from deep-sea hydrothermal vent, was cloned and over-expressed in E. coli BL21. The recombinant SufS protein was purified by one-step affinity chromatography. The TPY SufS contained a well conserved motif RXGHHCA as found in that of other microorganisms, suggesting that it belonged to group II of cysteine desulfurase family. The recombinant TPY SufS could catalyze the conversion of l-cysteine to l-alanine and produce persulfide, and the enzyme activity was 95 μ/μL of sulfur ion per minute. The growth of E. coli BL21 was promoted by over-expressing TPY SufS in vivo or by directly adding recombinant TPY SufS in the medium (4.3-4.5 × 108 cells/mL vs. 3.2-3.5 × 108 cells/mL). Furthermore, the highest cell density of E. coli BL21 when the TPY SufS was over-expressed was about 3.5 times that of the control groups in the presence of sodium thiosulfate. These results indicate that the SUF system as the only assembly system of iron-sulfur clusters not only has significant roles in survival of S. acidophilus TPY, but also might be important for combating with high content of sulfide.
Collapse
Affiliation(s)
- Yuguang Wang
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen, 361005 People's Republic of China
- Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen, 361005 People's Republic of China
| | - Qian Liu
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen, 361005 People's Republic of China
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 People's Republic of China
| | - Hongbo Zhou
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 People's Republic of China
| | - Xinhua Chen
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen, 361005 People's Republic of China
- College of Animal Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002 People's Republic of China
- Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen, 361005 People's Republic of China
| |
Collapse
|
17
|
Blauenburg B, Mielcarek A, Altegoer F, Fage CD, Linne U, Bange G, Marahiel MA. Crystal Structure of Bacillus subtilis Cysteine Desulfurase SufS and Its Dynamic Interaction with Frataxin and Scaffold Protein SufU. PLoS One 2016; 11:e0158749. [PMID: 27382962 PMCID: PMC4934914 DOI: 10.1371/journal.pone.0158749] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 06/21/2016] [Indexed: 12/31/2022] Open
Abstract
The biosynthesis of iron sulfur (Fe-S) clusters in Bacillus subtilis is mediated by a SUF-type gene cluster, consisting of the cysteine desulfurase SufS, the scaffold protein SufU, and the putative chaperone complex SufB/SufC/SufD. Here, we present the high-resolution crystal structure of the SufS homodimer in its product-bound state (i.e., in complex with pyrodoxal-5'-phosphate, alanine, Cys361-persulfide). By performing hydrogen/deuterium exchange (H/DX) experiments, we characterized the interaction of SufS with SufU and demonstrate that SufU induces an opening of the active site pocket of SufS. Recent data indicate that frataxin could be involved in Fe-S cluster biosynthesis by facilitating iron incorporation. H/DX experiments show that frataxin indeed interacts with the SufS/SufU complex at the active site. Our findings deepen the current understanding of Fe-S cluster biosynthesis, a complex yet essential process, in the model organism B. subtilis.
Collapse
Affiliation(s)
- Bastian Blauenburg
- Department of Chemistry, Biochemistry, Hans-Meerwein Str. 4, Philipps University Marburg, 35043 Marburg, Germany
| | - Andreas Mielcarek
- Department of Chemistry, Biochemistry, Hans-Meerwein Str. 4, Philipps University Marburg, 35043 Marburg, Germany
| | - Florian Altegoer
- LOEWE Center for Synthetic Microbiology, Philipps University Marburg, 35043 Marburg, Germany
| | - Christopher D. Fage
- Department of Chemistry, Biochemistry, Hans-Meerwein Str. 4, Philipps University Marburg, 35043 Marburg, Germany
| | - Uwe Linne
- Department of Chemistry, Biochemistry, Hans-Meerwein Str. 4, Philipps University Marburg, 35043 Marburg, Germany
| | - Gert Bange
- Department of Chemistry, Biochemistry, Hans-Meerwein Str. 4, Philipps University Marburg, 35043 Marburg, Germany
- LOEWE Center for Synthetic Microbiology, Philipps University Marburg, 35043 Marburg, Germany
| | - Mohamed A. Marahiel
- Department of Chemistry, Biochemistry, Hans-Meerwein Str. 4, Philipps University Marburg, 35043 Marburg, Germany
| |
Collapse
|
18
|
Dai Y, Kim D, Dong G, Busenlehner LS, Frantom PA, Outten FW. SufE D74R Substitution Alters Active Site Loop Dynamics To Further Enhance SufE Interaction with the SufS Cysteine Desulfurase. Biochemistry 2015; 54:4824-33. [PMID: 26171726 DOI: 10.1021/acs.biochem.5b00663] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Many essential metalloproteins require iron-sulfur (Fe-S) cluster cofactors for their function. In vivo persulfide formation from l-cysteine is a key step in the biogenesis of Fe-S clusters in most organisms. In Escherichia coli, the SufS cysteine desulfurase mobilizes persulfide from l-cysteine via a PLP-dependent ping-pong reaction. SufS requires the SufE partner protein to transfer the persulfide to the SufB Fe-S cluster scaffold. Without SufE, the SufS enzyme fails to efficiently turn over and remains locked in the persulfide-bound state. Coordinated protein-protein interactions mediate sulfur transfer from SufS to SufE. Multiple studies have suggested that SufE must undergo a conformational change to extend its active site Cys loop during sulfur transfer from SufS. To test this putative model, we mutated SufE Asp74 to Arg (D74R) to increase the dynamics of the SufE Cys51 loop. Amide hydrogen/deuterium exchange mass spectrometry (HDX-MS) analysis of SufE D74R revealed an increase in solvent accessibility and dynamics in the loop containing the active site Cys51 used to accept persulfide from SufS. Our results indicate that the mutant protein has a stronger binding affinity for SufS than that of wild-type SufE. In addition, SufE D74R can still enhance SufS desulfurase activity and did not show saturation at higher SufE D74R concentrations, unlike wild-type SufE. These results show that dynamic changes may shift SufE to a sulfur-acceptor state that interacts more strongly with SufS.
Collapse
Affiliation(s)
- Yuyuan Dai
- †Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Dokyong Kim
- ‡Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Guangchao Dong
- †Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Laura S Busenlehner
- ‡Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Patrick A Frantom
- ‡Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - F Wayne Outten
- †Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| |
Collapse
|
19
|
Outten FW. Recent advances in the Suf Fe-S cluster biogenesis pathway: Beyond the Proteobacteria. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:1464-9. [PMID: 25447545 DOI: 10.1016/j.bbamcr.2014.11.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 10/31/2014] [Accepted: 11/03/2014] [Indexed: 01/21/2023]
Abstract
Fe-S clusters play critical roles in cellular function throughout all three kingdoms of life. Consequently, Fe-S cluster biogenesis systems are present in most organisms. The Suf (sulfur formation) system is the most ancient of the three characterized Fe-S cluster biogenesis pathways, which also include the Isc and Nif systems. Much of the first work on the Suf system took place in Gram-negative Proteobacteria used as model organisms. These early studies led to a wealth of biochemical, genetic, and physiological information on Suf function. From those studies we have learned that SufB functions as an Fe-S scaffold in conjunction with SufC (and in some cases SufD). SufS and SufE together mobilize sulfur for cluster assembly and SufA traffics the complete Fe-S cluster from SufB to target apo-proteins. However, recent progress on the Suf system in other organisms has opened up new avenues of research and new hypotheses about Suf function. This review focuses primarily on the most recent discoveries about the Suf pathway and where those new models may lead the field. This article is part of a Special Issue entitled: Fe/S proteins: Analysis, structure, function, biogenesis and diseases.
Collapse
Affiliation(s)
- F Wayne Outten
- University of South Carolina, Department of Chemistry and Biochemistry, 631 Sumter Street, Columbia, SC 29208, USA.
| |
Collapse
|
20
|
Shared-intermediates in the biosynthesis of thio-cofactors: Mechanism and functions of cysteine desulfurases and sulfur acceptors. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:1470-80. [PMID: 25447671 DOI: 10.1016/j.bbamcr.2014.10.018] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 10/07/2014] [Accepted: 10/19/2014] [Indexed: 12/20/2022]
Abstract
Cysteine desulfurases utilize a PLP-dependent mechanism to catalyze the first step of sulfur mobilization in the biosynthesis of sulfur-containing cofactors. Sulfur activation and integration into thiocofactors involve complex mechanisms and intricate biosynthetic schemes. Cysteine desulfurases catalyze sulfur-transfer reactions from l-cysteine to sulfur acceptor molecules participating in the biosynthesis of thio-cofactors, including Fe-S clusters, thionucleosides, thiamin, biotin, and molybdenum cofactor. The proposed mechanism of cysteine desulfurases involves the PLP-dependent cleavage of the C-S bond from l-cysteine via the formation of a persulfide enzyme intermediate, which is considered the hallmark step in sulfur mobilization. The subsequent sulfur transfer reaction varies with the class of cysteine desulfurase and sulfur acceptor. IscS serves as a mecca for sulfur incorporation into a network of intertwined pathways for the biosynthesis of thio-cofactors. The involvement of a single enzyme interacting with multiple acceptors, the recruitment of shared-intermediates partaking roles in multiple pathways, and the participation of Fe-S enzymes denote the interconnectivity of pathways involving sulfur trafficking. In Bacillus subtilis, the occurrence of multiple cysteine desulfurases partnering with dedicated sulfur acceptors partially deconvolutes the routes of sulfur trafficking and assigns specific roles for these enzymes. Understanding the roles of promiscuous vs. dedicated cysteine desulfurases and their partnership with shared-intermediates in the biosynthesis of thio-cofactors will help to map sulfur transfer events across interconnected pathways and to provide insight into the hierarchy of sulfur incorporation into biomolecules. This article is part of a Special Issue entitled: Fe/S proteins: Analysis, structure, function, biogenesis and diseases.
Collapse
|
21
|
Boyd ES, Thomas KM, Dai Y, Boyd JM, Outten FW. Interplay between oxygen and Fe-S cluster biogenesis: insights from the Suf pathway. Biochemistry 2014; 53:5834-47. [PMID: 25153801 PMCID: PMC4172210 DOI: 10.1021/bi500488r] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
![]()
Iron–sulfur (Fe–S)
cluster metalloproteins conduct
essential functions in nearly all contemporary forms of life. The
nearly ubiquitous presence of Fe–S clusters and the fundamental
requirement for Fe–S clusters in both aerobic and anaerobic
Archaea, Bacteria, and Eukarya suggest that these clusters were likely
integrated into central metabolic pathways early in the evolution
of life prior to the widespread oxidation of Earth’s atmosphere.
Intriguingly, Fe–S cluster-dependent metabolism is sensitive
to disruption by oxygen because of the decreased bioavailability of
ferric iron as well as direct oxidation of sulfur trafficking intermediates
and Fe–S clusters by reactive oxygen species. This fact, coupled
with the ubiquity of Fe–S clusters in aerobic organisms, suggests
that organisms evolved with mechanisms that facilitate the biogenesis
and use of these essential cofactors in the presence of oxygen, which
gradually began to accumulate around 2.5 billion years ago as oxygenic
photosynthesis proliferated and reduced minerals that buffered against
oxidation were depleted. This review highlights the most ancient of
the Fe–S cluster biogenesis pathways, the Suf system, which
likely was present in early anaerobic forms of life. Herein, we use
the evolution of the Suf pathway to assess the relationships between
the biochemical functions and physiological roles of Suf proteins,
with an emphasis on the selective pressure of oxygen toxicity. Our
analysis suggests that diversification into oxygen-containing environments
disrupted iron and sulfur metabolism and was a main driving force
in the acquisition of accessory Suf proteins (such as SufD, SufE,
and SufS) by the core SufB–SufC scaffold complex. This analysis
provides a new framework for the study of Fe–S cluster biogenesis
pathways and Fe–S cluster-containing metalloenzymes and their
complicated patterns of divergence in response to oxygen.
Collapse
Affiliation(s)
- Eric S Boyd
- Department of Microbiology and Immunology, Montana State University , 109 Lewis Hall, Bozeman, Montana 59717, United States
| | | | | | | | | |
Collapse
|
22
|
Singh H, Dai Y, Outten FW, Busenlehner LS. Escherichia coli SufE sulfur transfer protein modulates the SufS cysteine desulfurase through allosteric conformational dynamics. J Biol Chem 2013; 288:36189-200. [PMID: 24196966 PMCID: PMC3868733 DOI: 10.1074/jbc.m113.525709] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 11/05/2013] [Indexed: 11/06/2022] Open
Abstract
Fe-S clusters are critical metallocofactors required for cell function. Fe-S cluster biogenesis is carried out by assembly machinery consisting of multiple proteins. Fe-S cluster biogenesis proteins work together to mobilize sulfide and iron, form the nascent cluster, traffic the cluster to target metalloproteins, and regulate the assembly machinery in response to cellular Fe-S cluster demand. A complex series of protein-protein interactions is required for the assembly machinery to function properly. Despite considerable progress in obtaining static three-dimensional structures of the assembly proteins, little is known about transient protein-protein interactions during cluster assembly or the role of protein dynamics in the cluster assembly process. The Escherichia coli cysteine desulfurase SufS (EC 2.8.1.7) and its accessory protein SufE work together to mobilize persulfide from L-cysteine, which is then donated to the SufB Fe-S cluster scaffold. Here we use amide hydrogen/deuterium exchange mass spectrometry (HDX-MS) to characterize SufS-SufE interactions and protein dynamics in solution. HDX-MS analysis shows that SufE binds near the SufS active site to accept persulfide from Cys-364. Furthermore, SufE binding initiates allosteric changes in other parts of the SufS structure that likely affect SufS catalysis and alter SufS monomer-monomer interactions. SufE enhances the initial l-cysteine substrate binding to SufS and formation of the external aldimine with pyridoxal phosphate required for early steps in SufS catalysis. Together, these results provide a new picture of the SufS-SufE sulfur transferase pathway and suggest a more active role for SufE in promoting the SufS cysteine desulfurase reaction for Fe-S cluster assembly.
Collapse
Affiliation(s)
- Harsimran Singh
- From the Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487 and
| | - Yuyuan Dai
- the Department of Chemistry and Biochemistry, The University of South Carolina, Columbia, South Carolina 29208
| | - F. Wayne Outten
- the Department of Chemistry and Biochemistry, The University of South Carolina, Columbia, South Carolina 29208
| | - Laura S. Busenlehner
- From the Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487 and
| |
Collapse
|
23
|
Kim S, Park S. Structural changes during cysteine desulfurase CsdA and sulfur acceptor CsdE interactions provide insight into the trans-persulfuration. J Biol Chem 2013; 288:27172-27180. [PMID: 23913692 DOI: 10.1074/jbc.m113.480277] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In Escherichia coli, three cysteine desulfurases (IscS, SufS, and CsdA) initiate the delivery of sulfur for various biological processes such as the biogenesis of Fe-S clusters. The sulfur generated as persulfide on a cysteine residue of cysteine desulfurases is further transferred to Fe-S scaffolds (e.g. IscU) or to intermediate cysteine-containing sulfur acceptors (e.g. TusA, SufE, and CsdE) prior to its utilization. Here, we report the structures of CsdA and the CsdA-CsdE complex, which provide insight into the sulfur transfer mediated by the trans-persulfuration reaction. Analysis of the structures indicates that the conformational flexibility of the active cysteine loop in CsdE is essential for accepting the persulfide from the cysteine of CsdA. Additionally, CsdA and CsdE invoke a different binding mode than those of previously reported cysteine desulfurase (IscS) and sulfur acceptors (TusA and IscU). Moreover, the conservation of interaction-mediating residues between CsdA/SufS and CsdE/SufE further suggests that the SufS-SufE interface likely resembles that of CsdA and CsdE.
Collapse
Affiliation(s)
- Sunmin Kim
- School of Systems Biomedical Science, Soongsil University, Seoul 156-743, Korea
| | - SangYoun Park
- School of Systems Biomedical Science, Soongsil University, Seoul 156-743, Korea.
| |
Collapse
|
24
|
Biogenesis of [Fe–S] cluster in Firmicutes: an unexploited field of investigation. Antonie Van Leeuwenhoek 2013; 104:283-300. [DOI: 10.1007/s10482-013-9966-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 06/28/2013] [Indexed: 10/26/2022]
|
25
|
Yamanaka Y, Zeppieri L, Nicolet Y, Marinoni EN, de Oliveira JS, Odaka M, Dean DR, Fontecilla-Camps JC. Crystal structure and functional studies of an unusual L-cysteine desulfurase from Archaeoglobus fulgidus. Dalton Trans 2012; 42:3092-9. [PMID: 23160436 DOI: 10.1039/c2dt32101g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
L-Cysteine desulfurase IscS and scaffold IscU proteins are universally involved in Fe/S cluster synthesis. The Archaeoglobus fulgidus (Af) genome encodes proteins having a high degree of primary structure similarity to IscS and IscU from other organisms. However, AfIscS is unusual because it lacks the active site lysine residue that normally forms an internal Schiff base with pyridoxal-phosphate (PLP) and serves as a base during catalysis. Our as-isolated recombinant AfIscS contains pyridoxamine phosphate (PMP) instead of the expected PLP and lacks desulfurase activity. We have solved its structure to 1.43 Å resolution and found that PMP binds non-covalently at the PLP site of the enzyme and displays significant disorder. However, the previously reported structure of recombinant Af(IscU-D35A-IscS)(2) contains an in vivo generated [Fe(2)S(2)] species within AfIscU and the question arises as to how its sulfides were generated. Here, we report that adding PLP to AfIscS produces an enzyme that displays in vitro L-cysteine desulfurase activity mediating the synthesis of a stable holo Af(IscU-D35A-IscS) complex.
Collapse
Affiliation(s)
- Yasuaki Yamanaka
- Department of Biotechnology and Life Science Graduate School of Technology, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Turowski VR, Busi MV, Gomez-Casati DF. Structural and functional studies of the mitochondrial cysteine desulfurase from Arabidopsis thaliana. MOLECULAR PLANT 2012; 5:1001-10. [PMID: 22511606 DOI: 10.1093/mp/sss037] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
AtNfs1 is the Arabidopsis thaliana mitochondrial homolog of the bacterial cysteine desulfurases NifS and IscS, having an essential role in cellular Fe-S cluster assembly. Homology modeling of AtNfs1m predicts a high global similarity with E. coli IscS showing a full conservation of residues involved in the catalytic site, whereas the chloroplastic AtNfs2 is more similar to the Synechocystis sp. SufS. Pull-down assays showed that the recombinant mature form, AtNfs1m, specifically binds to Arabidopsis frataxin (AtFH). A hysteretic behavior, with a lag phase of several minutes, was observed and hysteretic parameters were affected by pre-incubation with AtFH. Moreover, AtFH modulates AtNfs1m kinetics, increasing V(max) and decreasing the S(0.5) value for cysteine. Results suggest that AtFH plays an important role in the early steps of Fe-S cluster formation by regulating AtNfs1 activity in plant mitochondria.
Collapse
Affiliation(s)
- Valeria R Turowski
- Centro de Estudios Fotosintéticos y Bioquímicos, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | | | | |
Collapse
|
27
|
Chen F, Zhang Z, Lin K, Qian T, Zhang Y, You D, He X, Wang Z, Liang J, Deng Z, Wu G. Crystal structure of the cysteine desulfurase DndA from Streptomyces lividans which is involved in DNA phosphorothioation. PLoS One 2012; 7:e36635. [PMID: 22570733 PMCID: PMC3343029 DOI: 10.1371/journal.pone.0036635] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 04/04/2012] [Indexed: 11/18/2022] Open
Abstract
DNA phosphorothioation is widespread among prokaryotes, and might function to restrict gene transfer among different kinds of bacteria. There has been little investigation into the structural mechanism of the DNA phosphorothioation process. DndA is a cysteine desulfurase which is involved in the first step of DNA phosphorothioation. In this study, we determined the crystal structure of Streptomyces lividans DndA in complex with its covalently bound cofactor PLP, to a resolution of 2.4 Å. Our structure reveals the molecular mechanism that DndA employs to recognize its cofactor PLP, and suggests the potential binding site for the substrate L-cysteine on DndA. In contrast to previously determined structures of cysteine desulfurases, the catalytic cysteine of DndA was found to reside on a β strand. This catalytic cysteine is very far away from the presumable location of the substrate, suggesting that a conformational change of DndA is required during the catalysis process to bring the catalytic cysteine close to the substrate cysteine. Moreover, our in vitro enzymatic assay results suggested that this conformational change is unlikely to be a simple result of random thermal motion, since moving the catalytic cysteine two residues forward or backward in the primary sequence completely disabled the cysteine desulfurase activity of DndA.
Collapse
Affiliation(s)
- Fukun Chen
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Zhenyi Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Kui Lin
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- * E-mail: (KL); (GW)
| | - Tianle Qian
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Yan Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Delin You
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xinyi He
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Zhijun Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Jingdan Liang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Zixin Deng
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Geng Wu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- * E-mail: (KL); (GW)
| |
Collapse
|
28
|
Nagahara N. Catalytic site cysteines of thiol enzyme: sulfurtransferases. JOURNAL OF AMINO ACIDS 2010; 2011:709404. [PMID: 22332003 PMCID: PMC3276061 DOI: 10.4061/2011/709404] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Accepted: 11/09/2010] [Indexed: 11/20/2022]
Abstract
Thiol enzymes have single- or double-catalytic site cysteine residues and are redox active. Oxidoreductases and isomerases contain double-catalytic site cysteine residues, which are oxidized to a disulfide via a sulfenyl intermediate and reduced to a thiol or a thiolate. The redox changes of these enzymes are involved in their catalytic processes. On the other hand, transferases, and also some phosphatases and hydrolases, have a single-catalytic site cysteine residue. The cysteines are redox active, but their sulfenyl forms, which are inactive, are not well explained biologically. In particular, oxidized forms of sulfurtransferases, such as mercaptopyruvate sulfurtransferase and thiosulfate sulfurtransferase, are not reduced by reduced glutathione but by reduced thioredoxin. This paper focuses on why the catalytic site cysteine of sulfurtransferase is redox active.
Collapse
Affiliation(s)
- Noriyuki Nagahara
- Department of Environmental Medicine, Nippon Medical School, 1-1-5 Sendagi Bunkyo-ku, Tokyo 113-8602, Japan
| |
Collapse
|
29
|
Selbach B, Earles E, Dos Santos PC. Kinetic analysis of the bisubstrate cysteine desulfurase SufS from Bacillus subtilis. Biochemistry 2010; 49:8794-802. [PMID: 20822158 DOI: 10.1021/bi101358k] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cysteine is the major sulfur donor for thio cofactors in bacterial and eukaryotic systems. The first step in sulfur mobilization involves a PLP-dependent enzymatic mechanism. During catalysis, free cysteine is converted into alanine with the concomitant formation of a persulfide bond with the catalytic cysteine residue, thus forming a covalent enzyme intermediate. Cysteine desulfurases in their persulfurated forms serve as donors at the intersection of various cellular sulfur-requiring pathways. Most Gram-positive bacteria, including Bacillus subtilis, contain a cysteine desulfurase gene sufS located adjacent to the gene encoding the proposed Fe-S cluster scaffold SufU. In this work, we identified the participation of SufU as a substrate in the SufS catalytic mechanism. Development of a sensitive method for detection of alanine formed in the SufS reaction enabled the identification of its associated mechanistic features. Steady-state kinetic analysis of alanine formation provided evidence of a double-displacement mechanism (ping-pong) of the cysteine:SufU sulfurtransferase reaction catalyzed by SufS. Results from site-directed mutagenesis of the catalytic cysteine (SufS(C361A)) and iodoacetamide alkylation of SufU support the occurrence of persulfide sulfur transfer steps in the mechanism of SufS.
Collapse
Affiliation(s)
- Bruna Selbach
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109-7486, USA
| | | | | |
Collapse
|
30
|
Shi R, Proteau A, Villarroya M, Moukadiri I, Zhang L, Trempe JF, Matte A, Armengod ME, Cygler M. Structural basis for Fe-S cluster assembly and tRNA thiolation mediated by IscS protein-protein interactions. PLoS Biol 2010; 8:e1000354. [PMID: 20404999 PMCID: PMC2854127 DOI: 10.1371/journal.pbio.1000354] [Citation(s) in RCA: 205] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Accepted: 03/08/2010] [Indexed: 11/30/2022] Open
Abstract
Crystal structures reveal how distinct sites on the cysteine desulfurase IscS bind two different sulfur-acceptor proteins, IscU and TusA, to transfer sulfur atoms for iron-sulfur cluster biosynthesis and tRNA thiolation. The cysteine desulfurase IscS is a highly conserved master enzyme initiating sulfur transfer via persulfide to a range of acceptor proteins involved in Fe-S cluster assembly, tRNA modifications, and sulfur-containing cofactor biosynthesis. Several IscS-interacting partners including IscU, a scaffold for Fe-S cluster assembly; TusA, the first member of a sulfur relay leading to sulfur incorporation into the wobble uridine of several tRNAs; ThiI, involved in tRNA modification and thiamine biosynthesis; and rhodanese RhdA are sulfur acceptors. Other proteins, such as CyaY/frataxin and IscX, also bind to IscS, but their functional roles are not directly related to sulfur transfer. We have determined the crystal structures of IscS-IscU and IscS-TusA complexes providing the first insight into their different modes of binding and the mechanism of sulfur transfer. Exhaustive mutational analysis of the IscS surface allowed us to map the binding sites of various partner proteins and to determine the functional and biochemical role of selected IscS and TusA residues. IscS interacts with its partners through an extensive surface area centered on the active site Cys328. The structures indicate that the acceptor proteins approach Cys328 from different directions and suggest that the conformational plasticity of a long loop containing this cysteine is essential for the ability of IscS to transfer sulfur to multiple acceptor proteins. The sulfur acceptors can only bind to IscS one at a time, while frataxin and IscX can form a ternary complex with IscU and IscS. Our data support the role of frataxin as an iron donor for IscU to form the Fe-S clusters. Sulfur is incorporated into the backbone of almost all proteins in the form of the amino acids cysteine and methionine. In some proteins, sulfur is also present as iron–sulfur clusters, sulfur-containing vitamins, and cofactors. What's more, sulfur is important in the structure of tRNAs, which are crucial for translation of the genetic code from messenger RNA for protein synthesis. The biosynthetic pathways for assembly of these sulfur-containing molecules are generally well known, but the molecular details of how sulfur is delivered from protein to protein are less well understood. In bacteria, one of three pathways for sulfur delivery is the isc (iron-sulfur clusters) system. First, an enzyme called IscS extracts sulfur atoms from cysteine. This versatile enzyme can then interact with several proteins to deliver sulfur to various pathways that make iron–sulfur clusters or transfer sulfur to cofactors and tRNAs. This study describes in atomic detail precisely how IscS binds in a specific and yet distinct way to two different proteins: IscU (a scaffold protein for iron–sulfur cluster formation) and TusA (which delivers sulfur for tRNA modification). Furthermore, by introducing mutations into IscS, we have identified the region on the surface of this protein that is involved in binding its target proteins. These findings provide a molecular view of the protein–protein interactions involved in sulfur transfer and advance our understanding of how sulfur is delivered from one protein to another during biosynthesis of iron–sulfur clusters.
Collapse
Affiliation(s)
- Rong Shi
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Omi R, Kurokawa S, Mihara H, Hayashi H, Goto M, Miyahara I, Kurihara T, Hirotsu K, Esaki N. Reaction mechanism and molecular basis for selenium/sulfur discrimination of selenocysteine lyase. J Biol Chem 2010; 285:12133-9. [PMID: 20164179 DOI: 10.1074/jbc.m109.084475] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Selenocysteine lyase (SCL) catalyzes the pyridoxal 5'-phosphate-dependent removal of selenium from l-selenocysteine to yield l-alanine. The enzyme is proposed to function in the recycling of the micronutrient selenium from degraded selenoproteins containing selenocysteine residue as an essential component. The enzyme exhibits strict substrate specificity toward l-selenocysteine and no activity to its cognate l-cysteine. However, it remains unclear how the enzyme distinguishes between selenocysteine and cysteine. Here, we present mechanistic studies of selenocysteine lyase from rat. ESI-MS analysis of wild-type and C375A mutant SCL revealed that the catalytic reaction proceeds via the formation of an enzyme-bound selenopersulfide intermediate on the catalytically essential Cys-375 residue. UV-visible spectrum analysis and the crystal structure of SCL complexed with l-cysteine demonstrated that the enzyme reversibly forms a nonproductive adduct with l-cysteine. Cys-375 on the flexible loop directed l-selenocysteine, but not l-cysteine, to the correct position and orientation in the active site to initiate the catalytic reaction. These findings provide, for the first time, the basis for understanding how trace amounts of a selenium-containing substrate is distinguished from excessive amounts of its cognate sulfur-containing compound in a biological system.
Collapse
Affiliation(s)
- Rie Omi
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
The Oniom Method and its Applications to Enzymatic Reactions. CHALLENGES AND ADVANCES IN COMPUTATIONAL CHEMISTRY AND PHYSICS 2009. [DOI: 10.1007/978-1-4020-9956-4_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
|
33
|
Abstract
Iron-sulfur (Fe-S) clusters are required for critical biochemical pathways, including respiration, photosynthesis, and nitrogen fixation. Assembly of these iron cofactors is a carefully controlled process in cells to avoid toxicity from free iron and sulfide. Multiple Fe-S cluster assembly pathways are present in bacteria to carry out basal cluster assembly, stress-responsive cluster assembly, and enzyme-specific cluster assembly. Although biochemical and genetic characterization is providing a partial picture of in vivo Fe-S cluster assembly, a number of mechanistic questions remain unanswered. Furthermore, new factors involved in Fe-S cluster assembly and repair have recently been identified and are expanding the complexity of current models. Here we attempt to summarize recent advances and to highlight new avenues of research in the field of Fe-S cluster assembly.
Collapse
|
34
|
A catalytic mechanism that explains a low catalytic activity of serine dehydratase like-1 from human cancer cells: Crystal structure and site-directed mutagenesis studies. Biochim Biophys Acta Gen Subj 2008; 1780:809-18. [DOI: 10.1016/j.bbagen.2008.01.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 01/29/2008] [Accepted: 01/30/2008] [Indexed: 11/23/2022]
|
35
|
Fontecave M, Ollagnier-de-Choudens S. Iron-sulfur cluster biosynthesis in bacteria: Mechanisms of cluster assembly and transfer. Arch Biochem Biophys 2007; 474:226-37. [PMID: 18191630 DOI: 10.1016/j.abb.2007.12.014] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Revised: 12/13/2007] [Accepted: 12/16/2007] [Indexed: 11/17/2022]
Abstract
Iron-sulfur [Fe-S] clusters are ubiquitous ancient prosthetic groups that are required to sustain fundamental life processes. Formation of intracellular [Fe-S] clusters does not occur spontaneously but requires a complex biosynthetic machinery. Different types of [Fe-S] cluster assembly systems have been discovered. All of them have in common the requirement of a cysteine desulfurase and the participation of [Fe-S] scaffold proteins. The purpose of this review is to discuss various aspects of the molecular mechanisms of [Fe-S] cluster assembly in living organisms: (i) mechanism of sulfur donor enzymes, namely the cysteine desulfurases; (ii) mechanism by which clusters are preassembled on scaffold proteins and (iii) mechanism of [Fe-S] cluster transfer from scaffold to target proteins.
Collapse
|
36
|
Ganichkin OM, Xu XM, Carlson BA, Mix H, Hatfield DL, Gladyshev VN, Wahl MC. Structure and catalytic mechanism of eukaryotic selenocysteine synthase. J Biol Chem 2007; 283:5849-65. [PMID: 18093968 DOI: 10.1074/jbc.m709342200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In eukaryotes and Archaea, selenocysteine synthase (SecS) converts O-phospho-L-seryl-tRNA [Ser]Sec into selenocysteyl-tRNA [Ser]Sec using selenophosphate as the selenium donor compound. The molecular mechanisms underlying SecS activity are presently unknown. We have delineated a 450-residue core of mouse SecS, which retained full selenocysteyl-tRNA [Ser]Sec synthesis activity, and determined its crystal structure at 1.65 A resolution. SecS exhibits three domains that place it in the fold type I family of pyridoxal phosphate (PLP)-dependent enzymes. Two SecS monomers interact intimately and together build up two identical active sites around PLP in a Schiff-base linkage with lysine 284. Two SecS dimers further associate to form a homotetramer. The N terminus, which mediates tetramer formation, and a large insertion that remodels the active site set SecS aside from other members of the family. The active site insertion contributes to PLP binding and positions a glutamate next to the PLP, where it could repel substrates with a free alpha-carboxyl group, suggesting why SecS does not act on free O-phospho-l-serine. Upon soaking crystals in phosphate buffer, a previously disordered loop within the active site insertion contracted to form a phosphate binding site. Residues that are strictly conserved in SecS orthologs but variant in related enzymes coordinate the phosphate and upon mutation corrupt SecS activity. Modeling suggested that the phosphate loop accommodates the gamma-phosphate moiety of O-phospho-l-seryl-tRNA [Ser]Sec and, after phosphate elimination, binds selenophosphate to initiate attack on the proposed aminoacrylyl-tRNA [Ser]Sec intermediate. Based on these results and on the activity profiles of mechanism-based inhibitors, we offer a detailed reaction mechanism for the enzyme.
Collapse
Affiliation(s)
- Oleg M Ganichkin
- Max-Planck-Institut für Biophysikalische Chemie, Zelluläre Biochemie/Makromolekulare Röntgenkristallographie, Am Fassberg 11, D-37077 Göttingen, Germany
| | | | | | | | | | | | | |
Collapse
|
37
|
Vignais PM, Billoud B. Occurrence, Classification, and Biological Function of Hydrogenases: An Overview. Chem Rev 2007; 107:4206-72. [PMID: 17927159 DOI: 10.1021/cr050196r] [Citation(s) in RCA: 1026] [Impact Index Per Article: 60.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Paulette M. Vignais
- CEA Grenoble, Laboratoire de Biochimie et Biophysique des Systèmes Intégrés, UMR CEA/CNRS/UJF 5092, Institut de Recherches en Technologies et Sciences pour le Vivant (iRTSV), 17 rue des Martyrs, 38054 Grenoble cedex 9, France, and Atelier de BioInformatique Université Pierre et Marie Curie (Paris 6), 12 rue Cuvier, 75005 Paris, France
| | - Bernard Billoud
- CEA Grenoble, Laboratoire de Biochimie et Biophysique des Systèmes Intégrés, UMR CEA/CNRS/UJF 5092, Institut de Recherches en Technologies et Sciences pour le Vivant (iRTSV), 17 rue des Martyrs, 38054 Grenoble cedex 9, France, and Atelier de BioInformatique Université Pierre et Marie Curie (Paris 6), 12 rue Cuvier, 75005 Paris, France
| |
Collapse
|
38
|
Fukunaga R, Yokoyama S. Structural insights into the second step of RNA-dependent cysteine biosynthesis in archaea: crystal structure of Sep-tRNA:Cys-tRNA synthase from Archaeoglobus fulgidus. J Mol Biol 2007; 370:128-41. [PMID: 17512006 DOI: 10.1016/j.jmb.2007.04.050] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 04/06/2007] [Accepted: 04/17/2007] [Indexed: 11/23/2022]
Abstract
In the ancient organisms, methanogenic archaea, lacking the canonical cysteinyl-tRNA synthetase, Cys-tRNA(Cys) is produced by an indirect pathway, in which O-phosphoseryl-tRNA synthetase ligates O-phosphoserine (Sep) to tRNA(Cys) and Sep-tRNA:Cys-tRNA synthase (SepCysS) converts Sep-tRNA(Cys) to Cys-tRNA(Cys). In this study, the crystal structure of SepCysS from Archaeoglobus fulgidus has been determined at 2.4 A resolution. SepCysS forms a dimer, composed of monomers bearing large and small domains. The large domain harbors the seven-stranded beta-sheet, which is typical of the pyridoxal 5'-phosphate (PLP)-dependent enzymes. In the active site, which is located near the dimer interface, PLP is covalently bound to the side-chain of the conserved Lys209. In the proximity of PLP, a sulfate ion is bound by the side-chains of the conserved Arg79, His103, and Tyr104 residues. The active site is located deep within the large, basic cleft to accommodate Sep-tRNA(Cys). On the basis of the surface electrostatic potential, the amino acid residue conservation mapping, the position of the bound sulfate ion, and the substrate amino acid binding manner in other PLP-dependent enzymes, a binding model of Sep-tRNA(Cys) to SepCysS was constructed. One of the three strictly conserved Cys residues (Cys39, Cys42, or Cys247), of one subunit may play a crucial role in the catalysis in the active site of the other subunit.
Collapse
Affiliation(s)
- Ryuya Fukunaga
- Department of Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | | |
Collapse
|
39
|
Layer G, Gaddam SA, Ayala-Castro CN, Ollagnier-de Choudens S, Lascoux D, Fontecave M, Outten FW. SufE transfers sulfur from SufS to SufB for iron-sulfur cluster assembly. J Biol Chem 2007; 282:13342-50. [PMID: 17350958 DOI: 10.1074/jbc.m608555200] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Iron-sulfur (Fe-S) clusters are key metal cofactors of metabolic, regulatory, and stress response proteins in most organisms. The unique properties of these clusters make them susceptible to disruption by iron starvation or oxidative stress. Both iron and sulfur can be perturbed under stress conditions, leading to Fe-S cluster defects. Bacteria and higher plants contain a specialized system for Fe-S cluster biosynthesis under stress, namely the Suf pathway. In Escherichia coli the Suf pathway consists of six proteins with functions that are only partially characterized. Here we describe how the SufS and SufE proteins interact with the SufBCD protein complex to facilitate sulfur liberation from cysteine and donation for Fe-S cluster assembly. It was previously shown that the cysteine desulfurase SufS donates sulfur to the sulfur transfer protein SufE. We have found here that SufE in turn interacts with the SufB protein for sulfur transfer to that protein. The interaction occurs only if SufC is present. Furthermore, SufB can act as a site for Fe-S cluster assembly in the Suf system. This provides the first evidence of a novel site for Fe-S cluster assembly in the SufBCD complex.
Collapse
Affiliation(s)
- Gunhild Layer
- Laboratoire de Chimie et Biologie des Métaux, iRTSV/LCBM, Commissariat a l'Energie Atomique/CNRS/Universite Joseph Fourier, CEA-Grenoble, UMR 5249, 17 Avenue des Martyrs, 38054 Grenoble Cedex 09, France
| | | | | | | | | | | | | |
Collapse
|
40
|
Campanini B, Schiaretti F, Abbruzzetti S, Kessler D, Mozzarelli A. Sulfur Mobilization in Cyanobacteria. J Biol Chem 2006; 281:38769-80. [PMID: 17020883 DOI: 10.1074/jbc.m607098200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Sulfur mobilization represents one of the key steps in ubiquitous Fe-S clusters assembly and is performed by a recently characterized set of proteins encompassing cysteine desulfurases, assembly factors, and shuttle proteins. Despite the evolutionary conservation of these proteins, some degree of variability among organisms was observed, which might reflect functional specialization. L-Cyst(e)ine lyase (C-DES), a pyridoxal 5'-phosphatedependent enzyme identified in the cyanobacterium Synechocystis, was reported to use preferentially cystine over cysteine with production of cysteine persulfide, pyruvate, and ammonia. In this study, we demonstrate that C-DES sequences are present in all cyanobacterial genomes and constitute a new family of sulfur-mobilizing enzymes, distinct from cysteine desulfurases. The functional properties of C-DES from Synechocystis sp. PCC 6714 were investigated under pre-steady-state and steady-state conditions. Single wavelength and rapid scanning stopped-flow kinetic data indicate that the internal aldimine reacts with cystine forming an external aldimine that rapidly decays to a transient quinonoid species and stable tautomers of the alpha-aminoacrylate Schiff base. In the presence of cysteine, the transient formation of a dipolar species precedes the selective and stable accumulation of the enolimine tautomer of the external aldimine, with no formation of the alpha-aminoacrylate Schiff base under reducing conditions. Effective sulfur mobilization from cystine might represent a mechanism that allows adaptation of cyanobacteria to different environmental conditions and to light-dark cycles.
Collapse
Affiliation(s)
- Barbara Campanini
- Department of Biochemistry and Molecular Biology, University of Parma, 43100 Parma, Italy
| | | | | | | | | |
Collapse
|
41
|
Abstract
Sulfur is a functionally important element of living matter. Incorporation into biomolecules occurs by two basic strategies. Sulfide is added to an activated acceptor in the biosynthesis of cysteine, from which methionine, coenzyme A and a number of biologically important thiols can be constructed. By contrast, the biosyntheses of iron sulfur clusters, cofactors such as thiamin, molybdopterin, biotin and lipoic acid, and the thio modification of tRNA require an activated sulfur species termed persulfidic sulfur (R-S-SH) instead of sulfide. Persulfidic sulfur is produced enzymatically with the IscS protein, the SufS protein and rhodanese being the most prominent biocatalysts. This review gives an overview of sulfur incorporation into biomolecules in prokaryotes with a special emphasis on the properties and the enzymatic generation of persulfidic sulfur as well as its use in biosynthetic pathways.
Collapse
Affiliation(s)
- Dorothea Kessler
- Biochemiezentrum Heidelberg, Universität Heidelberg, Heidelberg, Germany.
| |
Collapse
|
42
|
Barras F, Loiseau L, Py B. How Escherichia coli and Saccharomyces cerevisiae build Fe/S proteins. Adv Microb Physiol 2006; 50:41-101. [PMID: 16221578 DOI: 10.1016/s0065-2911(05)50002-x] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Owing to the versatile electronic properties of iron and sulfur, iron sulfur (Fe/S) clusters are perfectly suited for sensing changes in environmental conditions and regulating protein properties accordingly. Fe/S proteins have been recruited in a wide array of diverse biological processes, including electron transfer chains, metabolic pathways and gene regulatory circuits. Chemistry has revealed the great diversity of Fe/S clusters occurring in proteins. The question now is to understand how iron and sulfur come together to form Fe/S clusters and how these clusters are subsequently inserted into apoproteins. Iron, sulfide and reducing conditions were found to be sufficient for successful maturation of many apoproteins in vitro, opening the possibility that insertion might be a spontaneous event. However, as in many other biological pathways such as protein folding, genetic analyses revealed that Fe/S cluster biogenesis and insertion depend in vivo upon auxiliary proteins. This was brought to light by studies on Azotobacter vinelandii nitrogenase, which, in particular, led to the concept of scaffold proteins, the role of which would be to allow transient assembly of Fe/S cluster. These studies paved the way toward the identification of the ISC and SUF systems, subjects of the present review that allow Fe/S cluster assembly into apoproteins of most organisms. Despite the recent discovery of the SUF and ISC systems, remarkable progress has been made in our understanding of their molecular composition and biochemical mechanisms. Such a rapid increase in our knowledge arose from a convergent interest from researchers engaged in unrelated fields and whose complementary expertise covered most experimental approaches used in biology. Also, the high conservation of ISC and SUF systems throughout a wide array of organisms helped cross-feeding between studies. The ISC system is conserved in eubacteria and most eukaryotes, while the SUF system arises in eubacteria, archaea, plants and parasites. ISC and SUF systems share a common core function made of a cysteine desulfurase, which acts as a sulfur donor, and scaffold proteins, which act as sulfur and iron acceptors. The ISC and SUF systems also exhibit important differences. In particular, the ISC system includes an Hsp70/Hsp40-like pair of chaperones, while the SUF system involves an unorthodox ATP-binding cassette (ABC)-like component. The role of these two sets of ATP-hydrolyzing proteins in Fe/S cluster biogenesis remains unclear. Both systems are likely to target overlapping sets of apoproteins. However, regulation and phenotypic studies in E. coli, which synthesizes both types of systems, leads us to envisage ISC as the house-keeping one that functions under normal laboratory conditions, while the SUF system appears to be required in harsh environmental conditions such as oxidative stress and iron starvation. In Saccharomyces cerevisiae, the ISC system is located in the mitochondria and its function is necessary for maturation of both mitochondrial and cytosolic Fe/S proteins. Here, we attempt to provide the first comprehensive review of the ISC and SUF systems since their discovery in the mid and late 1990s. Most emphasis is put on E. coli and S. cerevisiae models with reference to other organisms when their analysis provided us with information of particular significance. We aim at covering information made available on each Isc and Suf component by the different experimental approaches, including physiology, gene regulation, genetics, enzymology, biophysics and structural biology. It is our hope that this parallel coverage will facilitate the identification of both similarities and specificities of ISC and SUF systems.
Collapse
Affiliation(s)
- Frédéric Barras
- Laboratoire de Chimie Bactérienne, UPR-CNRS 9043 and LRC-CNRS-CEA 35v, Institut de Biologie Structurale et Microbiologie, 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | | | | |
Collapse
|
43
|
Ye H, Abdel-Ghany SE, Anderson TD, Pilon-Smits EAH, Pilon M. CpSufE activates the cysteine desulfurase CpNifS for chloroplastic Fe-S cluster formation. J Biol Chem 2006; 281:8958-69. [PMID: 16455656 DOI: 10.1074/jbc.m512737200] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
CpNifS, a cysteine desulfurase required to supply sulfur for ironsulfur cluster biogenesis in Arabidopsis thaliana chloroplasts, belongs to a class of NifS-like enzymes with low endogenous cysteine desulfurase activity. Its bacterial homologue SufS is stimulated by SufE. Here we characterize the Arabidopsis chloroplast protein CpSufE, which has an N-terminal SufE-like domain and a C-terminal BolA-like domain unique to higher plants. CpSufE is targeted to the chloroplast stroma, indicated by green fluorescent protein localization and immunoblot experiments. Like CpNifS, CpSufE is expressed in all major tissues, with higher expression in green parts. Its expression is light-dependent and regulated at the mRNA level. The addition of purified recombinant CpSufE increased the Vmax for the cysteine desulfurase activity of CpNifS over 40-fold and decreased the KM toward cysteine from 0.1 to 0.043 mm. In contrast, CpSufE addition decreased the affinity of CpNifS for selenocysteine, as indicated by an increase in the KM from 2.9 to 4.17 mm, and decreased the Vmax for selenocysteine lyase activity by 30%. CpSufE forms dynamic complexes with CpNifS, indicated by gel filtration, native PAGE, and affinity chromatography experiments. A mutant of CpSufE in which the single cysteine was changed to serine was not active in stimulating CpNifS, although it did compete with WT CpSufE. The iron-sulfur cluster reconstitution activity of the CpNifS-CpSufE complex toward apoferredoxin was 20-fold higher than that of CpNifS alone. We conclude that CpNifS and CpSufE together form a cysteine desulfurase required for iron-sulfur cluster formation in chloroplasts.
Collapse
Affiliation(s)
- Hong Ye
- Biology Department, Colorado State University, Fort Collins, Colorado 80523
| | | | | | | | | |
Collapse
|
44
|
Fontecave M, Choudens SOD, Py B, Barras F. Mechanisms of iron-sulfur cluster assembly: the SUF machinery. J Biol Inorg Chem 2005; 10:713-21. [PMID: 16211402 DOI: 10.1007/s00775-005-0025-1] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2005] [Accepted: 08/23/2005] [Indexed: 11/26/2022]
Abstract
Biosynthesis of iron-sulfur clusters is a cellular process which depends on complex protein machineries. Escherichia coli contains two such biosynthetic systems, ISC and SUF. In this review article we specifically make a presentation of the various Suf proteins and discuss the molecular mechanisms by which these proteins work together to assemble Fe and S atoms within a scaffold and to transfer the resulting cluster to target proteins.
Collapse
Affiliation(s)
- M Fontecave
- Laboratoire de Chimie et Biochimie des Centres Rédox Biologiques, DRDC-CB, CEA/CNRS/Université Joseph Fourier, CEA-Grenoble, Grenoble Cedex 09, France.
| | | | | | | |
Collapse
|
45
|
Abstract
Iron-sulfur [Fe-S] clusters are ubiquitous and evolutionary ancient prosthetic groups that are required to sustain fundamental life processes. Owing to their remarkable structural plasticity and versatile chemical/electronic features [Fe-S] clusters participate in electron transfer, substrate binding/activation, iron/sulfur storage, regulation of gene expression, and enzyme activity. Formation of intracellular [Fe-S] clusters does not occur spontaneously but requires a complex biosynthetic machinery. Three different types of [Fe-S] cluster biosynthetic systems have been discovered, and all of them are mechanistically unified by the requirement for a cysteine desulfurase and the participation of an [Fe-S] cluster scaffolding protein. Important mechanistic questions related to [Fe-S] cluster biosynthesis involve the molecular details of how [Fe-S] clusters are assembled on scaffold proteins, how [Fe-S] clusters are transferred from scaffolds to target proteins, how various accessory proteins participate in [Fe-S] protein maturation, and how the biosynthetic process is regulated.
Collapse
Affiliation(s)
- Deborah C Johnson
- Department of Biochemistry, Virginia Polytechnic Institute, Blacksburg, Virginia 24061, USA.
| | | | | | | |
Collapse
|
46
|
Loiseau L, Ollagnier-de Choudens S, Lascoux D, Forest E, Fontecave M, Barras F. Analysis of the heteromeric CsdA-CsdE cysteine desulfurase, assisting Fe-S cluster biogenesis in Escherichia coli. J Biol Chem 2005; 280:26760-9. [PMID: 15901727 DOI: 10.1074/jbc.m504067200] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Biogenesis of iron-sulfur (Fe-S) cluster-containing proteins relies on assistance of complex machineries. To date three systems, NIF, ISC, and SUF, were reported to allow maturation of Fe-S proteins. Here we report that the csdA-csdE (formally ygdK) genes of Escherichia coli constitute a sulfur-generating system referred to as CSD which also contributes to Fe-S biogenesis in vivo. This conclusion was reached by applying a thorough combination of both in vivo and in vitro strategies and techniques. Yeast two-hybrid analysis allowed us to show that CsdA and CsdE interact. Enzymology analysis showed that CsdA cysteine desulfurase activity is increased 2-fold in the presence of CsdE. Mass spectrometry analysis and site-directed mutagenesis showed that residue Cys-61 from CsdE acted as an acceptor site for sulfur provided by cysteine desulfurase activity of CsdA. Genetic investigations revealed that the csdA-csdE genes could act as multicopy suppressors of iscS mutation. Moreover, both in vitro and in vivo investigations pointed to a specific connection between the CSD system and quinolinate synthetase NadA.
Collapse
Affiliation(s)
- Laurent Loiseau
- Laboratoire de Chimie Bactérienne, UPR-CNRS 9043, Institut de Biologie Structurale et Microbiologie, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France
| | | | | | | | | | | |
Collapse
|
47
|
Prabhakar R, Morokuma K, Musaev DG. A comparative study of various computational approaches in calculating the structure of pyridoxal 5'-phosphate (PLP)-dependent beta-lyase protein. The importance of protein environment. J Comput Chem 2005; 26:443-6. [PMID: 15688436 DOI: 10.1002/jcc.20179] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Various computational approaches, using molecular mechanics (Amber), semiempirical (AM1), density functional (B3LYP), and various ONIOM methods, have been comparatively investigated for the structure of Escherichia coli NifS CsdB protein. The structure of the entire monomer containing 407 amino acid residues and 579 surrounding water molecules has been optimized. The full geometry optimization in the "active site-only" approach (including only active site atoms) has been found to give the largest root-mean-square (RMS) deviation from the X-ray structure; a much better agreement has been achieved by keeping the atoms leading to the backbones of some amino acids frozen in their positions in the X-ray structure. The best agreement has been attained by including the surrounding protein in the calculations using the two-layer ONIOM (B3LYP:Amber) approach. The results presented in this study conclusively demonstrate the importance of the protein/active-site interaction on the active-site structure of the enzyme. The present theoretical study represents the largest system studied at the ONIOM level to date, containing 7992 atoms, including 84 atoms in the QM region and rest in the MM region.
Collapse
Affiliation(s)
- Rajeev Prabhakar
- Cherry L. Emerson Center for Scientific Computation, and Department of Chemistry, Emory University, 1515 Dickey Dr., Atlanta, Georgia 30322, USA
| | | | | |
Collapse
|
48
|
Abstract
Considerable work still needs to be done to understand more fully the basic processes going on inside the non-photosynthetic plastid organelle of Plasmodium spp., the causative agent of malaria. Following an explosion of genomic and transcriptional information in recent years, research workers are still analysing these data looking for new material relevant to the plastid. Several metabolic and housekeeping functions based on bacterial biochemistry have been elucidated and this has given impetus to finding lead inhibitors based on established anti-microbials. Structural investigations of plastid-associated enzymes identified as potential targets have begun. This review gives a perspective on the research to date and hopes to emphasize that a practical outcome for the clinic should be an important focus of future efforts. Malaria parasites have become resistant to front-line anti-malarials that are widely used and were formerly dependable. This has become a worrying problem in many regions where malaria is endemic. The time lag between hunting for new inhibitors and their application as pharmaceuticals is so long and costly that a steady stream of new ventures has to be undertaken to give a reasonable chance of finding affordable and appropriate anti-malarials for the future. Attempts to find inhibitors of the plastid organelle of the malaria parasite should be intensified in such programmes.
Collapse
Affiliation(s)
- R J M Iain Wilson
- National Institute for Medical Research, Mill Hill, London, NW7 1AA, UK.
| |
Collapse
|
49
|
Goldsmith-Fischman S, Kuzin A, Edstrom WC, Benach J, Shastry R, Xiao R, Acton TB, Honig B, Montelione GT, Hunt JF. The SufE sulfur-acceptor protein contains a conserved core structure that mediates interdomain interactions in a variety of redox protein complexes. J Mol Biol 2004; 344:549-65. [PMID: 15522304 DOI: 10.1016/j.jmb.2004.08.074] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2004] [Revised: 08/09/2004] [Accepted: 08/10/2004] [Indexed: 12/21/2022]
Abstract
The isc and suf operons in Escherichia coli represent alternative genetic systems optimized to mediate the essential metabolic process of iron-sulfur cluster (Fe-S) assembly under basal or oxidative-stress conditions, respectively. Some of the proteins in these two operons share strong sequence homology, e.g. the cysteine desulfurases IscS and SufS, and presumably play the same role in the oxygen-sensitive assembly process. However, other proteins in these operons share no significant homology and occur in a mutually exclusive manner in Fe-S assembly operons in other organisms (e.g. IscU and SufE). These latter proteins presumably play distinct roles adapted to the different assembly mechanisms used by the two systems. IscU has three invariant cysteine residues that function as a template for Fe-S assembly while accepting a sulfur atom from IscS. SufE, in contrast, does not function as an Fe-S assembly template but has been suggested to function as a shuttle protein that uses a persulfide linkage to a single invariant cysteine residue to transfer a sulfur atom from SufS to an alternative Fe-S assembly template. Here, we present and analyze the 2.0A crystal structure of E.coli SufE. The structure shows that the persulfide-forming cysteine occurs at the tip of a loop with elevated B-factors, where its side-chain is buried from solvent exposure in a hydrophobic cavity located beneath a highly conserved surface. Despite the lack of sequence homology, the core of SufE shows strong structural similarity to IscU, and the sulfur-acceptor site in SufE coincides with the location of the cysteine residues mediating Fe-S cluster assembly in IscU. Thus, a conserved core structure is implicated in mediating the interactions of both SufE and IscU with the mutually homologous cysteine desulfurase enzymes present in their respective operons. A similar core structure is observed in a domain found in a variety of Fe-S cluster containing flavoenzymes including xanthine dehydrogenase, where it also mediates interdomain interactions. Therefore, the core fold of SufE/IscU has been adapted to mediate interdomain interactions in diverse redox protein systems in the course of evolution.
Collapse
Affiliation(s)
- Sharon Goldsmith-Fischman
- Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Kessler D. Slr0077 of Synechocystis has cysteine desulfurase as well as cystine lyase activity. Biochem Biophys Res Commun 2004; 320:571-7. [PMID: 15219867 DOI: 10.1016/j.bbrc.2004.06.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2004] [Indexed: 11/25/2022]
Abstract
NifS-like proteins activate sulfur for a variety of biosynthetic purposes. The genome of the cyanobacterium Synechocystis contains 4 nifS-related sequences of which only the slr0077 gene seems to be essential. In this report the heterologous production of the Slr0077 protein, its purification, and catalytic properties are described. Slr0077 produces alanine as well as pyruvate from cyst(e)ine as substrate; the product ratio depends on the redox conditions. Alanine is the typical product of orthodox NifS proteins, pyruvate formation is typical of the cystine lyase of Synechocystis which is the most peculiar member of the NifS protein family. The specific activities of Slr0077 for both reaction types are low as compared to the prototypic enzymes. Upon reaction with thiol-alkylating agents Slr0077 is not readily inactivated unlike NifS. The unique properties of Slr0077 add to the emerging picture that the NifS family of proteins comprises enzymes with a variety of distinct reactivities.
Collapse
Affiliation(s)
- Dorothea Kessler
- Universität Heidelberg, Biochemiezentrum, D-69120 Heidelberg, Germany.
| |
Collapse
|