1
|
Bak DW, Weerapana E. Proteomic strategies to interrogate the Fe-S proteome. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119791. [PMID: 38925478 PMCID: PMC11365765 DOI: 10.1016/j.bbamcr.2024.119791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 05/23/2024] [Accepted: 06/19/2024] [Indexed: 06/28/2024]
Abstract
Iron‑sulfur (Fe-S) clusters, inorganic cofactors composed of iron and sulfide, participate in numerous essential redox, non-redox, structural, and regulatory biological processes within the cell. Though structurally and functionally diverse, the list of all proteins in an organism capable of binding one or more Fe-S clusters is referred to as its Fe-S proteome. Importantly, the Fe-S proteome is highly dynamic, with continuous cluster synthesis and delivery by complex Fe-S cluster biogenesis pathways. This cluster delivery is balanced out by processes that can result in loss of Fe-S cluster binding, such as redox state changes, iron availability, and oxygen sensitivity. Despite continued expansion of the Fe-S protein catalogue, it remains a challenge to reliably identify novel Fe-S proteins. As such, high-throughput techniques that can report on native Fe-S cluster binding are required to both identify new Fe-S proteins, as well as characterize the in vivo dynamics of Fe-S cluster binding. Due to the recent rapid growth in mass spectrometry, proteomics, and chemical biology, there has been a host of techniques developed that are applicable to the study of native Fe-S proteins. This review will detail both the current understanding of the Fe-S proteome and Fe-S cluster biology as well as describing state-of-the-art proteomic strategies for the study of Fe-S clusters within the context of a native proteome.
Collapse
Affiliation(s)
- Daniel W Bak
- Department of Chemistry, Boston College, Chestnut Hill, MA, United States of America.
| | - Eranthie Weerapana
- Department of Chemistry, Boston College, Chestnut Hill, MA, United States of America.
| |
Collapse
|
2
|
Misra J, Mettert EL, Kiley PJ. Functional analysis of the methylerythritol phosphate pathway terminal enzymes IspG and IspH from Zymomonas mobilis. Microbiol Spectr 2024; 12:e0425623. [PMID: 38785428 PMCID: PMC11218510 DOI: 10.1128/spectrum.04256-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 04/05/2024] [Indexed: 05/25/2024] Open
Abstract
Isoprenoids are a diverse family of compounds that are synthesized from two isomeric compounds, isopentenyl diphosphate and dimethylallyl diphosphate. In most bacteria, isoprenoids are produced from the essential methylerythritol phosphate (MEP) pathway. The terminal enzymes of the MEP pathway IspG and IspH are [4Fe-4S] cluster proteins, and in Zymomonas mobilis, the substrates of IspG and IspH accumulate in cells in response to O2, suggesting possible lability of their [4Fe-4S] clusters. Here, we show using complementation assays in Escherichia coli that even under anaerobic conditions, Z. mobilis IspG and IspH are not as functional as their E. coli counterparts, requiring higher levels of expression to rescue viability. A deficit of the sulfur utilization factor (SUF) Fe-S cluster biogenesis pathway did not explain the reduced function of Z. mobilis IspG and IspH since no improvement in viability was observed in E. coli expressing the Z. mobilis SUF pathway or having increased expression of the E. coli SUF pathway. Complementation of single and double mutants with various combinations of Z. mobilis and E. coli IspG and IspH indicated that optimal growth required the pairing of IspG and IspH from the same species. Furthermore, Z. mobilis IspH conferred an O2-sensitive growth defect to E. coli that could be partially rescued by co-expression of Z. mobilis IspG. In vitro analysis showed O2 sensitivity of the [4Fe-4S] cluster of both Z. mobilis IspG and IspH. Altogether, our data indicate an important role of the cognate protein IspG in Z. mobilis IspH function under both aerobic and anaerobic conditions. IMPORTANCE Isoprenoids are one of the largest classes of natural products, exhibiting diversity in structure and function. They also include compounds that are essential for cellular life across the biological world. In bacteria, isoprenoids are derived from two precursors, isopentenyl diphosphate and dimethylallyl diphosphate, synthesized primarily by the methylerythritol phosphate pathway. The aerotolerant Z. mobilis has the potential for methylerythritol phosphate pathway engineering by diverting some of the glucose that is typically efficiently converted into ethanol to produce isoprenoid precursors to make bioproducts and biofuels. Our data revealed the surprising finding that Z. mobilis IspG and IspH need to be co-optimized to improve flux via the methyl erythritol phosphate pathway in part to evade the oxygen sensitivity of IspH.
Collapse
Affiliation(s)
- Jyotsna Misra
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Erin L. Mettert
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Patricia J. Kiley
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| |
Collapse
|
3
|
Bulka O, Picott K, Mahadevan R, Edwards EA. From mec cassette to rdhA: a key Dehalobacter genomic neighborhood in a chloroform and dichloromethane-transforming microbial consortium. Appl Environ Microbiol 2024; 90:e0073224. [PMID: 38819127 PMCID: PMC11218628 DOI: 10.1128/aem.00732-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Accepted: 05/20/2024] [Indexed: 06/01/2024] Open
Abstract
Chloroform (CF) and dichloromethane (DCM) are groundwater contaminants of concern due to their high toxicity and inhibition of important biogeochemical processes such as methanogenesis. Anaerobic biotransformation of CF and DCM has been well documented but typically independently of one another. CF is the electron acceptor for certain organohalide-respiring bacteria that use reductive dehalogenases (RDases) to dechlorinate CF to DCM. In contrast, known DCM degraders use DCM as their electron donor, which is oxidized using a series of methyltransferases and associated proteins encoded by the mec cassette to facilitate the entry of DCM to the Wood-Ljungdahl pathway. The SC05 culture is an enrichment culture sold commercially for bioaugmentation, which transforms CF via DCM to CO2. This culture has the unique ability to dechlorinate CF to DCM using electron equivalents provided by the oxidation of DCM to CO2. Here, we use metagenomic and metaproteomic analyses to identify the functional genes involved in each of these transformations. Though 91 metagenome-assembled genomes were assembled, the genes for an RDase-named acdA-and a complete mec cassette were found to be encoded on a single contig belonging to Dehalobacter. AcdA and critical Mec proteins were also highly expressed by the culture. Heterologously expressed AcdA dechlorinated CF and other chloroalkanes but had 100-fold lower activity on DCM. Overall, the high expression of Mec proteins and the activity of AcdA suggest a Dehalobacter capable of dechlorination of CF to DCM and subsequent mineralization of DCM using the mec cassette. IMPORTANCE Chloroform (CF) and dichloromethane (DCM) are regulated groundwater contaminants. A cost-effective approach to remove these pollutants from contaminated groundwater is to employ microbes that transform CF and DCM as part of their metabolism, thus depleting the contamination as the microbes continue to grow. In this work, we investigate bioaugmentation culture SC05, a mixed microbial consortium that effectively and simultaneously degrades both CF and DCM coupled to the growth of Dehalobacter. We identified the functional genes responsible for the transformation of CF and DCM in SC05. These genetic biomarkers provide a means to monitor the remediation process in the field.
Collapse
Affiliation(s)
- Olivia Bulka
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Katherine Picott
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Radhakrishnan Mahadevan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Elizabeth A. Edwards
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
4
|
Garcia PS, Gribaldo S, Barras F. When iron and sulfur met on an anoxic planet and eventually made clusters essential for life. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119730. [PMID: 38631441 DOI: 10.1016/j.bbamcr.2024.119730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 03/11/2024] [Accepted: 04/04/2024] [Indexed: 04/19/2024]
Abstract
[FeS] clusters are co-factors that are essential for life and are synthesized by dedicated multiprotein cellular machineries. In this review, we present the current scenario for the emergence and the diversification of the [FeS] cluster biosynthesis machineries. In addition to well-known NIF, ISC and SUF machineries, two alternative minimal systems, SMS, and MIS, were recently identified. Taxonomic distribution and phylogeny analyses indicate that SMS and MIS were present in the Last Universal Common Ancestor (LUCA), well before the increase of oxygen on Earth. ISC, SUF and NIF systems emerged later in the history of life. The possible reasons for the emergence and diversification of these machineries are discussed.
Collapse
Affiliation(s)
- Pierre Simon Garcia
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Department of Microbiology, Unit Stress Adaptation and Metabolism in Enterobacteria, Paris, France; Institut Pasteur, Université Paris Cité, Department of Microbiology, Unit Evolutionary Biology of the Microbial Cell, Paris, France
| | - Simonetta Gribaldo
- Institut Pasteur, Université Paris Cité, Department of Microbiology, Unit Evolutionary Biology of the Microbial Cell, Paris, France
| | - Frédéric Barras
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Department of Microbiology, Unit Stress Adaptation and Metabolism in Enterobacteria, Paris, France.
| |
Collapse
|
5
|
Shomar H, Bokinsky G. Harnessing iron‑sulfur enzymes for synthetic biology. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119718. [PMID: 38574823 DOI: 10.1016/j.bbamcr.2024.119718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 03/13/2024] [Accepted: 03/25/2024] [Indexed: 04/06/2024]
Abstract
Reactions catalysed by iron-sulfur (Fe-S) enzymes appear in a variety of biosynthetic pathways that produce valuable natural products. Harnessing these biosynthetic pathways by expression in microbial cell factories grown on an industrial scale would yield enormous economic and environmental benefits. However, Fe-S enzymes often become bottlenecks that limits the productivity of engineered pathways. As a consequence, achieving the production metrics required for industrial application remains a distant goal for Fe-S enzyme-dependent pathways. Here, we identify and review three core challenges in harnessing Fe-S enzyme activity, which all stem from the properties of Fe-S clusters: 1) limited Fe-S cluster supply within the host cell, 2) Fe-S cluster instability, and 3) lack of specialized reducing cofactor proteins often required for Fe-S enzyme activity, such as enzyme-specific flavodoxins and ferredoxins. We highlight successful methods developed for a variety of Fe-S enzymes and electron carriers for overcoming these difficulties. We use heterologous nitrogenase expression as a grand case study demonstrating how each of these challenges can be addressed. We predict that recent breakthroughs in protein structure prediction and design will prove well-suited to addressing each of these challenges. A reliable toolkit for harnessing Fe-S enzymes in engineered metabolic pathways will accelerate the development of industry-ready Fe-S enzyme-dependent biosynthesis pathways.
Collapse
Affiliation(s)
- Helena Shomar
- Institut Pasteur, université Paris Cité, Inserm U1284, Diversité moléculaire des microbes (Molecular Diversity of Microbes lab), 75015 Paris, France
| | - Gregory Bokinsky
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands.
| |
Collapse
|
6
|
Eskandari A, Nezhad NG, Leow TC, Rahman MBA, Oslan SN. Essential factors, advanced strategies, challenges, and approaches involved for efficient expression of recombinant proteins in Escherichia coli. Arch Microbiol 2024; 206:152. [PMID: 38472371 DOI: 10.1007/s00203-024-03871-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 12/31/2023] [Accepted: 01/25/2024] [Indexed: 03/14/2024]
Abstract
Producing recombinant proteins is a major accomplishment of biotechnology in the past century. Heterologous hosts, either eukaryotic or prokaryotic, are used for the production of these proteins. The utilization of microbial host systems continues to dominate as the most efficient and affordable method for biotherapeutics and food industry productions. Hence, it is crucial to analyze the limitations and advantages of microbial hosts to enhance the efficient production of recombinant proteins on a large scale. E. coli is widely used as a host for the production of recombinant proteins. Researchers have identified certain obstacles with this host, and given the growing demand for recombinant protein production, there is an immediate requirement to enhance this host. The following review discusses the elements contributing to the manifestation of recombinant protein. Subsequently, it sheds light on innovative approaches aimed at improving the expression of recombinant protein. Lastly, it delves into the obstacles and optimization methods associated with translation, mentioning both cis-optimization and trans-optimization, producing soluble recombinant protein, and engineering the metal ion transportation. In this context, a comprehensive description of the distinct features will be provided, and this knowledge could potentially enhance the expression of recombinant proteins in E. coli.
Collapse
Affiliation(s)
- Azadeh Eskandari
- Enzyme and Microbial Technology Research Centre, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
- Department of Biochemistry, FacultyofBiotechnologyand BiomolecularSciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | - Nima Ghahremani Nezhad
- Enzyme and Microbial Technology Research Centre, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | - Thean Chor Leow
- Enzyme and Microbial Technology Research Centre, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
- Enzyme Technology and X-Ray Crystallography Laboratory, VacBio 5, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | | | - Siti Nurbaya Oslan
- Enzyme and Microbial Technology Research Centre, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
- Department of Biochemistry, FacultyofBiotechnologyand BiomolecularSciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
- Enzyme Technology and X-Ray Crystallography Laboratory, VacBio 5, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
| |
Collapse
|
7
|
Solomon JB, Liu YA, Górecki K, Quechol R, Lee CC, Jasniewski AJ, Hu Y, Ribbe MW. Heterologous expression of a fully active Azotobacter vinelandii nitrogenase Fe protein in Escherichia coli. mBio 2023; 14:e0257223. [PMID: 37909748 PMCID: PMC10746259 DOI: 10.1128/mbio.02572-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 09/27/2023] [Indexed: 11/03/2023] Open
Abstract
IMPORTANCE The heterologous expression of a fully active Azotobacter vinelandii Fe protein (AvNifH) has never been accomplished. Given the functional importance of this protein in nitrogenase catalysis and assembly, the successful expression of AvNifH in Escherichia coli as reported herein supplies a key element for the further development of heterologous expression systems that explore the catalytic versatility of the Fe protein, either on its own or as a key component of nitrogenase, for nitrogenase-based biotechnological applications in the future. Moreover, the "clean" genetic background of the heterologous expression host allows for an unambiguous assessment of the effect of certain nif-encoded protein factors, such as AvNifM described in this work, in the maturation of AvNifH, highlighting the utility of this heterologous expression system in further advancing our understanding of the complex biosynthetic mechanism of nitrogenase.
Collapse
Affiliation(s)
- Joseph B. Solomon
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
- Department of Chemistry, University of California, Irvine, California, USA
| | - Yiling A. Liu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Kamil Górecki
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Robert Quechol
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Chi Chung Lee
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Andrew J. Jasniewski
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Markus W. Ribbe
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
- Department of Chemistry, University of California, Irvine, California, USA
| |
Collapse
|
8
|
Hati D, Brault A, Gupta M, Fletcher K, Jacques JF, Labbé S, Outten CE. Iron homeostasis proteins Grx4 and Fra2 control activity of the Schizosaccharomyces pombe iron repressor Fep1 by facilitating [2Fe-2S] cluster removal. J Biol Chem 2023; 299:105419. [PMID: 37923140 PMCID: PMC10704371 DOI: 10.1016/j.jbc.2023.105419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 10/12/2023] [Accepted: 10/26/2023] [Indexed: 11/07/2023] Open
Abstract
The Bol2 homolog Fra2 and monothiol glutaredoxin Grx4 together play essential roles in regulating iron homeostasis in Schizosaccharomyces pombe. In vivo studies indicate that Grx4 and Fra2 act as coinhibitory partners that inactivate the transcriptional repressor Fep1 in response to iron deficiency. In Saccharomyces cerevisiae, Bol2 is known to form a [2Fe-2S]-bridged heterodimer with the monothiol Grxs Grx3 and Grx4, with the cluster ligands provided by conserved residues in Grx3/4 and Bol2 as well as GSH. In this study, we characterized this analogous [2Fe-2S]-bridged Grx4-Fra2 complex in S. pombe by identifying the specific residues in Fra2 that act as ligands for the Fe-S cluster and are required to regulate Fep1 activity. We present spectroscopic and biochemical evidence confirming the formation of a [2Fe-2S]-bridged Grx4-Fra2 heterodimer with His66 and Cys29 from Fra2 serving as Fe-S cluster ligands in S. pombe. In vivo transcription and growth assays confirm that both His66 and Cys29 are required to fully mediate the response of Fep1 to low iron conditions. Furthermore, we analyzed the interaction between Fep1 and Grx4-Fra2 using CD spectroscopy to monitor changes in Fe-S cluster coordination chemistry. These experiments demonstrate unidirectional [2Fe-2S] cluster transfer from Fep1 to Grx4-Fra2 in the presence of GSH, revealing the Fe-S cluster dependent mechanism of Fep1 inactivation mediated by Grx4 and Fra2 in response to iron deficiency.
Collapse
Affiliation(s)
- Debolina Hati
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, USA
| | - Ariane Brault
- Département de Biochimie et de Génomique Fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Malini Gupta
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, USA
| | - Kylie Fletcher
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, USA
| | - Jean-François Jacques
- Département de Biochimie et de Génomique Fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Simon Labbé
- Département de Biochimie et de Génomique Fonctionnelle, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Caryn E Outten
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, USA.
| |
Collapse
|
9
|
Witkowska M, Jedrzejczak RP, Joachimiak A, Cavdar O, Malankowska A, Skowron PM, Zylicz-Stachula A. Promising approaches for the assembly of the catalytically active, recombinant Desulfomicrobium baculatum hydrogenase with substitutions at the active site. Microb Cell Fact 2023; 22:134. [PMID: 37479997 PMCID: PMC10362691 DOI: 10.1186/s12934-023-02127-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 06/17/2023] [Indexed: 07/23/2023] Open
Abstract
BACKGROUND Hydrogenases (H2ases) are metalloenzymes capable of the reversible conversion of protons and electrons to molecular hydrogen. Exploiting the unique enzymatic activity of H2ases can lead to advancements in the process of biohydrogen evolution and green energy production. RESULTS Here we created of a functional, optimized operon for rapid and robust production of recombinant [NiFe] Desulfomicrobium baculatum hydrogenase (Dmb H2ase). The conversion of the [NiFeSe] Dmb H2ase to [NiFe] type was performed on genetic level by site-directed mutagenesis. The native dmb operon includes two structural H2ase genes, coding for large and small subunits, and an additional gene, encoding a specific maturase (protease) that is essential for the proper maturation of the enzyme. Dmb, like all H2ases, needs intricate bio-production machinery to incorporate its crucial inorganic ligands and cofactors. Strictly anaerobic, sulfate reducer D. baculatum bacteria are distinct, in terms of their biology, from E. coli. Thus, we introduced a series of alterations within the native dmb genes. As a result, more than 100 elements, further compiled into 32 operon variants, were constructed. The initial requirement for a specific maturase was omitted by the artificial truncation of the large Dmb subunit. The assembly of the produced H2ase subunit variants was investigated both, in vitro and in vivo. This approach resulted in 4 recombinant [NiFe] Dmb enzyme variants, capable of H2 evolution. The aim of this study was to overcome the gene expression, protein biosynthesis, maturation and ligand loading bottlenecks for the easy, fast, and cost-effective delivery of recombinant [NiFe] H2ase, using a commonly available E. coli strains. CONCLUSION The optimized genetic constructs together with the developed growth and purification procedures appear to be a promising platform for further studies toward fully-active and O2 tolerant, recombinant [NiFeSe] Dmb H2ase, resembling the native Dmb enzyme. It could likely be achieved by selective cysteine to selenocysteine substitution within the active site of the [NiFe] Dmb variant.
Collapse
Affiliation(s)
- Malgorzata Witkowska
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland
| | - Robert P Jedrzejczak
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Andrzej Joachimiak
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Onur Cavdar
- Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland
| | - Anna Malankowska
- Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland
| | - Piotr M Skowron
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland
| | - Agnieszka Zylicz-Stachula
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland.
| |
Collapse
|
10
|
A Diverged Transcriptional Network for Usage of Two Fe-S Cluster Biogenesis Machineries in the Delta-Proteobacterium Myxococcus xanthus. mBio 2023; 14:e0300122. [PMID: 36656032 PMCID: PMC9973013 DOI: 10.1128/mbio.03001-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Myxococcus xanthus possesses two Fe-S cluster biogenesis machineries, ISC (iron-sulfur cluster) and SUF (sulfur mobilization). Here, we show that in comparison to the phylogenetically distant Enterobacteria, which also have both machineries, M. xanthus evolved an independent transcriptional scheme to coordinately regulate the expression of these machineries. This transcriptional response is directed by RisR, which we show to belong to a phylogenetically distant and biochemically distinct subgroup of the Rrf2 transcription factor family, in comparison to IscR that regulates the isc and suf operons in Enterobacteria. We report that RisR harbors an Fe-S cluster and that holo-RisR acts as a repressor of both the isc and suf operons, in contrast to Escherichia coli, where holo-IscR represses the isc operon whereas apo-IscR activates the suf operon. In addition, we establish that the nature of the cluster and the DNA binding sites of RisR, in the isc and suf operons, diverge from those of IscR. We further show that in M. xanthus, the two machineries appear to be fully interchangeable in maintaining housekeeping levels of Fe-S cluster biogenesis and in synthesizing the Fe-S cluster for their common regulator, RisR. We also demonstrate that in response to oxidative stress and iron limitation, transcriptional upregulation of the M. xanthus isc and suf operons was mediated solely by RisR and that the contribution of the SUF machinery was greater than the ISC machinery. Altogether, these findings shed light on the diversity of homeostatic mechanisms exploited by bacteria to coordinately use two Fe-S cluster biogenesis machineries. IMPORTANCE Fe-S proteins are ubiquitous and control a wide variety of key biological processes; therefore, maintaining Fe-S cluster homeostasis is an essential task for all organisms. Here, we provide the first example of how a bacterium from the Deltaproteobacteria branch coordinates expression of two Fe-S cluster biogenesis machineries. The results revealed a new model of coordination, highlighting the unique and common features that have independently emerged in phylogenetically distant bacteria to maintain Fe-S cluster homeostasis in response to environmental changes. Regulation is orchestrated by a previously uncharacterized transcriptional regulator, RisR, belonging to the Rrf2 superfamily, whose members are known to sense diverse environmental stresses frequently encountered by bacteria. Understanding how M. xanthus maintains Fe-S cluster homeostasis via RisR regulation revealed a strategy reflective of the aerobic lifestyle of this organsim. This new knowledge also paves the way to improve production of Fe-S-dependent secondary metabolites using M. xanthus as a chassis.
Collapse
|
11
|
Jansing M, Mielenbrink S, Rosenbach H, Metzger S, Span I. Maturation strategy influences expression levels and cofactor occupancy in Fe-S proteins. J Biol Inorg Chem 2023; 28:187-204. [PMID: 36527507 PMCID: PMC9981529 DOI: 10.1007/s00775-022-01972-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 11/17/2022] [Indexed: 12/23/2022]
Abstract
Iron-sulfur clusters are ubiquitous cofactors required for fundamental biological processes. Structural and spectroscopic analysis of Fe-S proteins is often limited by low cluster occupancy in recombinantly produced proteins. In this work, we report a systematic comparison of different maturation strategies for three well-established [4Fe-4S] proteins. Aconitase B, HMBPP reductase (IspH), and quinolinate synthase (NadA) were used as model proteins as they have previously been characterized. The protein production strategies include expression of the gene of interest in BL21(DE3) cells, maturation of the apo protein using chemical or semi-enzymatic reconstitution, co-expression with two different plasmids containing the iron-sulfur cluster (isc) or sulfur formation (suf) operon, a cell strain lacking IscR, the transcriptional regulator of the ISC machinery, and an engineered "SufFeScient" derivative of BL21(DE3). Our results show that co-expression of a Fe-S biogenesis pathway influences the protein yield and the cluster content of the proteins. The presence of the Fe-S cluster is contributing to correct folding and structural stability of the proteins. In vivo maturation reduces the formation of Fe-S aggregates, which occur frequently when performing chemical reconstitution. Furthermore, we show that the in vivo strategies can be extended to the radical SAM protein ThnB, which was previously only maturated by chemical reconstitution. Our results shed light on the differences of in vitro and in vivo Fe-S cluster maturation and points out the pitfalls of chemical reconstitution.
Collapse
Affiliation(s)
- Melissa Jansing
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Steffen Mielenbrink
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Hannah Rosenbach
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Sabine Metzger
- MS-Platform Biocenter, Cluster of Excellence on Plant Science (CEPLAS), University of Cologne, Zülpicher Strasse 47B, 50674 Cologne, Germany
| | - Ingrid Span
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany. .,Bioanorganische Chemie, Department Chemie und Pharmazie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 1, 91058, Erlangen, Germany.
| |
Collapse
|
12
|
Richardson KH, Seif-Eddine M, Sills A, Roessler MM. Controlling and exploiting intrinsic unpaired electrons in metalloproteins. Methods Enzymol 2022; 666:233-296. [PMID: 35465921 DOI: 10.1016/bs.mie.2022.02.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Electron paramagnetic resonance spectroscopy encompasses a versatile set of techniques that allow detailed insight into intrinsically occurring paramagnetic centers in metalloproteins and enzymes that undergo oxidation-reduction reactions. In this chapter, we discuss the process from isolating the protein to acquiring and analyzing pulse EPR spectra, adopting a practical perspective. We start with considerations when preparing the protein sample, explain techniques and procedures available for determining the reduction potential of the redox-active center of interest and provide details on methodologies to trap a given paramagnetic state for detailed pulse EPR studies, with an emphasis on biochemical and spectroscopic tools available when multiple EPR-active species are present. We elaborate on some of the most commonly used pulse EPR techniques and the choices the user has to make, considering advantages and disadvantages and how to avoid pitfalls. Examples are provided throughout.
Collapse
Affiliation(s)
| | - Maryam Seif-Eddine
- Imperial College London, Molecular Sciences Research Hub, London, United Kingdom
| | - Adam Sills
- Imperial College London, Molecular Sciences Research Hub, London, United Kingdom
| | - Maxie M Roessler
- Imperial College London, Molecular Sciences Research Hub, London, United Kingdom.
| |
Collapse
|
13
|
D'Angelo F, Fernández-Fueyo E, Garcia PS, Shomar H, Pelosse M, Manuel RR, Büke F, Liu S, van den Broek N, Duraffourg N, de Ram C, Pabst M, Bouveret E, Gribaldo S, Py B, Ollagnier de Choudens S, Barras F, Bokinsky G. Cellular assays identify barriers impeding iron-sulfur enzyme activity in a non-native prokaryotic host. eLife 2022; 11:70936. [PMID: 35244541 PMCID: PMC8896826 DOI: 10.7554/elife.70936] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 02/03/2022] [Indexed: 11/24/2022] Open
Abstract
Iron-sulfur (Fe-S) clusters are ancient and ubiquitous protein cofactors and play irreplaceable roles in many metabolic and regulatory processes. Fe-S clusters are built and distributed to Fe-S enzymes by dedicated protein networks. The core components of these networks are widely conserved and highly versatile. However, Fe-S proteins and enzymes are often inactive outside their native host species. We sought to systematically investigate the compatibility of Fe-S networks with non-native Fe-S enzymes. By using collections of Fe-S enzyme orthologs representative of the entire range of prokaryotic diversity, we uncovered a striking correlation between phylogenetic distance and probability of functional expression. Moreover, coexpression of a heterologous Fe-S biogenesis pathway increases the phylogenetic range of orthologs that can be supported by the foreign host. We also find that Fe-S enzymes that require specific electron carrier proteins are rarely functionally expressed unless their taxon-specific reducing partners are identified and co-expressed. We demonstrate how these principles can be applied to improve the activity of a radical S-adenosyl methionine(rSAM) enzyme from a Streptomyces antibiotic biosynthesis pathway in Escherichia coli. Our results clarify how oxygen sensitivity and incompatibilities with foreign Fe-S and electron transfer networks each impede heterologous activity. In particular, identifying compatible electron transfer proteins and heterologous Fe-S biogenesis pathways may prove essential for engineering functional Fe-S enzyme-dependent pathways.
Collapse
Affiliation(s)
- Francesca D'Angelo
- Unit Stress Adaptation and Metabolism of Enterobacteria, Department of Microbiology, Université de Paris, UMR CNRS 2001, Institut Pasteur, Paris, France
| | - Elena Fernández-Fueyo
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, Netherlands
| | - Pierre Simon Garcia
- Unit Stress Adaptation and Metabolism of Enterobacteria, Department of Microbiology, Université de Paris, UMR CNRS 2001, Institut Pasteur, Paris, France.,Institut Pasteur, Université de Paris, CNRS UMR6047, Evolutionary Biology of the Microbial Cell, Department of Microbiology, Paris, France
| | - Helena Shomar
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, Netherlands
| | - Martin Pelosse
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, Grenoble, France
| | - Rita Rebelo Manuel
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, Netherlands
| | - Ferhat Büke
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, Netherlands
| | - Siyi Liu
- Aix-Marseille Université-CNRS, Laboratoire de Chimie Bactérienne UMR 7283, Institut de Microbiologie de la Méditerranée, Institut Microbiologie Bioénergies Biotechnologie, Marseille, France
| | - Niels van den Broek
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, Netherlands
| | - Nicolas Duraffourg
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, Grenoble, France
| | - Carol de Ram
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
| | - Martin Pabst
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
| | - Emmanuelle Bouveret
- Unit Stress Adaptation and Metabolism of Enterobacteria, Department of Microbiology, Université de Paris, UMR CNRS 2001, Institut Pasteur, Paris, France
| | - Simonetta Gribaldo
- Institut Pasteur, Université de Paris, CNRS UMR6047, Evolutionary Biology of the Microbial Cell, Department of Microbiology, Paris, France
| | - Béatrice Py
- Aix-Marseille Université-CNRS, Laboratoire de Chimie Bactérienne UMR 7283, Institut de Microbiologie de la Méditerranée, Institut Microbiologie Bioénergies Biotechnologie, Marseille, France
| | | | - Frédéric Barras
- Unit Stress Adaptation and Metabolism of Enterobacteria, Department of Microbiology, Université de Paris, UMR CNRS 2001, Institut Pasteur, Paris, France
| | - Gregory Bokinsky
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, Netherlands
| |
Collapse
|
14
|
Heterologous expression of active Dehalobacter spp. respiratory reductive dehalogenases in Escherichia coli. Appl Environ Microbiol 2021; 88:e0199321. [PMID: 34851719 DOI: 10.1128/aem.01993-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Reductive dehalogenases (RDases) are a family of redox enzymes that are required for anaerobic organohalide respiration, a microbial process that is useful in bioremediation. Structural and mechanistic studies of these enzymes have been greatly impeded due to challenges in RDase heterologous expression, potentially because of their cobamide-dependence. There have been a few successful attempts at RDase production in unconventional heterologous hosts, but a robust method has yet to be developed. Here we outline a novel respiratory RDase expression system using Escherichia coli. The overexpression of E. coli's cobamide transport system, btu, and anaerobic expression conditions were found to be essential for production of active RDases from Dehalobacter - an obligate organohalide respiring bacterium. The expression system was validated on six enzymes with amino acid sequence identities as low as 28%. Dehalogenation activity was verified for each RDase by assaying cell-free extracts of small-scale expression cultures on various chlorinated substrates including chloroalkanes, chloroethenes, and hexachlorocyclohexanes. Two RDases, TmrA from Dehalobacter sp. UNSWDHB and HchA from Dehalobacter sp. HCH1, were purified by nickel affinity chromatography. Incorporation of the cobamide and iron-sulfur cluster cofactors was verified; though, the precise cobalamin incorporation could not be determined due to variance between methodologies, and the specific activity of TmrA was consistent with that of the native enzyme. The heterologous expression of respiratory RDases, particularly from obligate organohalide respiring bacteria, has been extremely challenging and unreliable. Here we present a relatively straightforward E. coli expression system that has performed well for a variety of Dehalobacter spp. RDases. IMPORTANCE Understanding microbial reductive dehalogenation is important to refine the global halogen cycle and to improve bioremediation of halogenated contaminants; however, studies of the family of enzymes responsible are limited. Characterization of reductive dehalogenase enzymes has largely eluded researchers due to the lack of a reliable and high-yielding production method. We are presenting an approach to express reductive dehalogenase enzymes from Dehalobacter, a key group of organisms used in bioremediation, in E. coli. This expression system will propel the study of reductive dehalogenases by facilitating their production and isolation, allowing researchers to pursue more in-depth questions about the activity and structure of these enzymes. This platform will also provide a starting point to improve the expression of reductive dehalogenases from many other organisms.
Collapse
|
15
|
Abstract
Building iron-sulfur (Fe-S) clusters and assembling Fe-S proteins are essential actions for life on Earth. The three processes that sustain life, photosynthesis, nitrogen fixation, and respiration, require Fe-S proteins. Genes coding for Fe-S proteins can be found in nearly every sequenced genome. Fe-S proteins have a wide variety of functions, and therefore, defective assembly of Fe-S proteins results in cell death or global metabolic defects. Compared to alternative essential cellular processes, there is less known about Fe-S cluster synthesis and Fe-S protein maturation. Moreover, new factors involved in Fe-S protein assembly continue to be discovered. These facts highlight the growing need to develop a deeper biological understanding of Fe-S cluster synthesis, holo-protein maturation, and Fe-S cluster repair. Here, we outline bacterial strategies used to assemble Fe-S proteins and the genetic regulation of these processes. We focus on recent and relevant findings and discuss future directions, including the proposal of using Fe-S protein assembly as an antipathogen target.
Collapse
|
16
|
Abstract
57Fe Mӧssbauer spectroscopy is unparalleled in the study of Fe-S cluster-containing proteins because of its unique ability to detect all forms of iron. Enrichment of biological samples with the 57Fe isotope and manipulation of experimental parameters such as temperature and magnetic field allow for elucidation of the number of Fe-S clusters present in a given protein, their nuclearity, oxidation state, geometry, and ligation environment, as well as any transient states relevant to enzyme chemistry. This chapter is arranged in five sections to help navigate an experimentalist to utilize 57Fe Mӧssbauer spectroscopy for delineating the role and structure of biological Fe-S clusters. The first section lays out the tools and technical considerations for the preparation of 57Fe-labeled samples. The choice of experimental parameters and their effects on the Mӧssbauer spectra are presented in the following two sections. The last two sections provide a theoretical and practical guide on spectral acquisition and analysis relevant to Fe-S centers.
Collapse
|
17
|
Corless EI, Antony E. Methods for Heterologous Overproduction of Fe-S Proteins. Methods Mol Biol 2021; 2353:69-78. [PMID: 34292544 DOI: 10.1007/978-1-0716-1605-5_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Proteins carrying iron-sulfur ([Fe-S]) clusters are critical to the basic metabolism of all organisms. Structural and biochemical investigations of many such [Fe-S] cluster proteins depend on recombinant overproduction using heterologous bacterial hosts such as Escherichia coli . Here, we describe a detailed procedure for the overproduction and purification of two oxygen-sensitive component proteins of the dark-operative protochlorophyllide oxidoreductase (DPOR) complex. The method relies on an engineered Escherichia coli cell line carrying a correction in its genome to restore the loss of a key [Fe-S] cluster biogenesis pathway. The method can also be potentially adapted for the overproduction of other Fe-S proteins.
Collapse
Affiliation(s)
- Elliot I Corless
- Department of Biological Sciences, Marquette University, Milwaukee, WI, USA
| | - Edwin Antony
- Department of Biological Sciences, Marquette University, Milwaukee, WI, USA.
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, USA.
| |
Collapse
|
18
|
Bhatwa A, Wang W, Hassan YI, Abraham N, Li XZ, Zhou T. Challenges Associated With the Formation of Recombinant Protein Inclusion Bodies in Escherichia coli and Strategies to Address Them for Industrial Applications. Front Bioeng Biotechnol 2021; 9:630551. [PMID: 33644021 PMCID: PMC7902521 DOI: 10.3389/fbioe.2021.630551] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 01/20/2021] [Indexed: 12/12/2022] Open
Abstract
Recombinant proteins are becoming increasingly important for industrial applications, where Escherichia coli is the most widely used bacterial host for their production. However, the formation of inclusion bodies is a frequently encountered challenge for producing soluble and functional recombinant proteins. To overcome this hurdle, different strategies have been developed through adjusting growth conditions, engineering host strains of E. coli, altering expression vectors, and modifying the proteins of interest. These approaches will be comprehensively highlighted with some of the new developments in this review. Additionally, the unique features of protein inclusion bodies, the mechanism and influencing factors of their formation, and their potential advantages will also be discussed.
Collapse
Affiliation(s)
- Arshpreet Bhatwa
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, ON, Canada
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
| | - Weijun Wang
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, ON, Canada
| | - Yousef I. Hassan
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, ON, Canada
| | - Nadine Abraham
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, ON, Canada
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Xiu-Zhen Li
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, ON, Canada
| | - Ting Zhou
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, ON, Canada
| |
Collapse
|
19
|
Carter TD, Outten FW. Ni-NTA Affinity Chromatography to Characterize Protein-Protein Interactions During Fe-S Cluster Biogenesis. Methods Mol Biol 2021; 2353:125-136. [PMID: 34292547 PMCID: PMC8969215 DOI: 10.1007/978-1-0716-1605-5_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Affinity chromatography can be repurposed to provide useful information about the specific partner protein(s) to which a protein of interest may bind as well as the relative binding affinity of that partner protein for the protein of interest. Here, we provide a protocol for an Ni-NTA affinity chromatography assay that may be utilized to uncover insightful information about the nature of protein-protein interactions during iron-sulfur (Fe-S) cluster biogenesis reactions.
Collapse
Affiliation(s)
- Terrell D Carter
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, USA
| | - F Wayne Outten
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, USA.
| |
Collapse
|
20
|
Corless EI, Saad Imran SM, Watkins MB, Bacik JP, Mattice JR, Patterson A, Danyal K, Soffe M, Kitelinger R, Seefeldt LC, Origanti S, Bennett B, Bothner B, Ando N, Antony E. The flexible N-terminus of BchL autoinhibits activity through interaction with its [4Fe-4S] cluster and released upon ATP binding. J Biol Chem 2021; 296:100107. [PMID: 33219127 PMCID: PMC7948495 DOI: 10.1074/jbc.ra120.016278] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/10/2020] [Accepted: 11/20/2020] [Indexed: 11/10/2022] Open
Abstract
A key step in bacteriochlorophyll biosynthesis is the reduction of protochlorophyllide to chlorophyllide, catalyzed by dark-operative protochlorophyllide oxidoreductase. Dark-operative protochlorophyllide oxidoreductase contains two [4Fe-4S]-containing component proteins (BchL and BchNB) that assemble upon ATP binding to BchL to coordinate electron transfer and protochlorophyllide reduction. But the precise nature of the ATP-induced conformational changes is poorly understood. We present a crystal structure of BchL in the nucleotide-free form where a conserved, flexible region in the N-terminus masks the [4Fe-4S] cluster at the docking interface between BchL and BchNB. Amino acid substitutions in this region produce a hyperactive enzyme complex, suggesting a role for the N-terminus in autoinhibition. Hydrogen-deuterium exchange mass spectrometry shows that ATP binding to BchL produces specific conformational changes leading to release of the flexible N-terminus from the docking interface. The release also promotes changes within the local environment surrounding the [4Fe-4S] cluster and promotes BchL-complex formation with BchNB. A key patch of amino acids, Asp-Phe-Asp (the 'DFD patch'), situated at the mouth of the BchL ATP-binding pocket promotes intersubunit cross stabilization of the two subunits. A linked BchL dimer with one defective ATP-binding site does not support protochlorophyllide reduction, illustrating nucleotide binding to both subunits as a prerequisite for the intersubunit cross stabilization. The masking of the [4Fe-4S] cluster by the flexible N-terminal region and the associated inhibition of the activity is a novel mechanism of regulation in metalloproteins. Such mechanisms are possibly an adaptation to the anaerobic nature of eubacterial cells with poor tolerance for oxygen.
Collapse
Affiliation(s)
- Elliot I Corless
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, USA; Department of Biochemistry, Saint Louis University School of Medicine, St Louis, Missouri, USA
| | | | - Maxwell B Watkins
- Department of Chemistry, Princeton University, Princeton, New Jersey, USA; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - John-Paul Bacik
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - Jenna R Mattice
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
| | - Angela Patterson
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
| | - Karamatullah Danyal
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah, USA
| | - Mark Soffe
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah, USA
| | - Robert Kitelinger
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, USA
| | - Lance C Seefeldt
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah, USA
| | - Sofia Origanti
- Department of Biology, Saint Louis University, St Louis, Missouri, USA
| | - Brian Bennett
- Department of Physics, Marquette University, Milwaukee, Wisconsin, USA
| | - Brian Bothner
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
| | - Nozomi Ando
- Department of Chemistry, Princeton University, Princeton, New Jersey, USA; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA.
| | - Edwin Antony
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, USA; Department of Biochemistry, Saint Louis University School of Medicine, St Louis, Missouri, USA.
| |
Collapse
|
21
|
Corless EI, Bennett B, Antony E. Substrate recognition induces sequential electron transfer across subunits in the nitrogenase-like DPOR complex. J Biol Chem 2020; 295:13630-13639. [PMID: 32737200 DOI: 10.1074/jbc.ra120.015151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 07/30/2020] [Indexed: 12/25/2022] Open
Abstract
A key step in bacteriochlorophyll biosynthesis is the reduction of protochlorophyllide (Pchlide) to chlorophyllide (Chlide), catalyzed by dark-operative protochlorophyllide oxidoreductase (DPOR). DPOR is made of electron donor (BchL) and acceptor (BchNB) component proteins. BchNB is further composed of two subunits each of BchN and BchB arranged as an α2β2 heterotetramer with two active sites for substrate reduction. Such oligomeric architectures are found in several other electron transfer (ET) complexes, but how this architecture influences activity is unclear. Here, we describe allosteric communication between the two identical active sites in Rhodobacter sphaeroides BchNB that drives sequential and asymmetric ET. Pchlide binding to one BchNB active site initiates ET from the pre-reduced [4Fe-4S] cluster of BchNB, a process similar to the deficit spending mechanism observed in the structurally related nitrogenase complex. Pchlide binding in one active site is recognized in trans by an Asp-274 from the opposing half, which is positioned to serve as the initial proton donor. A D274A variant DPOR binds to two Pchlide molecules in the BchNB complex, but only one is bound productively, stalling Pchlide reduction in both active sites. A half-active complex combining one WT and one D274A monomer also stalled after one electron was transferred in the WT half. We propose that such sequential electron transfer in oligomeric enzymes serves as a regulatory mechanism to ensure binding and recognition of the correct substrate. The findings shed light on the functional advantages imparted by the oligomeric architecture found in many electron transfer enzymes.
Collapse
Affiliation(s)
- Elliot I Corless
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin; Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri
| | - Brian Bennett
- Department of Physics, Marquette University, Milwaukee, Wisconsin
| | - Edwin Antony
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri.
| |
Collapse
|