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Kuzminov A. Bacterial nucleoid is a riddle wrapped in a mystery inside an enigma. J Bacteriol 2024; 206:e0021123. [PMID: 38358278 PMCID: PMC10994824 DOI: 10.1128/jb.00211-23] [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] [Indexed: 02/16/2024] Open
Abstract
Bacterial chromosome, the nucleoid, is traditionally modeled as a rosette of DNA mega-loops, organized around proteinaceous central scaffold by nucleoid-associated proteins (NAPs), and mixed with the cytoplasm by transcription and translation. Electron microscopy of fixed cells confirms dispersal of the cloud-like nucleoid within the ribosome-filled cytoplasm. Here, I discuss evidence that the nucleoid in live cells forms DNA phase separate from riboprotein phase, the "riboid." I argue that the nucleoid-riboid interphase, where DNA interacts with NAPs, transcribing RNA polymerases, nascent transcripts, and ssRNA chaperones, forms the transcription zone. An active part of phase separation, transcription zone enforces segregation of the centrally positioned information phase (the nucleoid) from the surrounding action phase (the riboid), where translation happens, protein accumulates, and metabolism occurs. I speculate that HU NAP mostly tiles up the nucleoid periphery-facilitating DNA mobility but also supporting transcription in the interphase. Besides extruding plectonemically supercoiled DNA mega-loops, condensins could compact them into solenoids of uniform rings, while HU could support rigidity and rotation of these DNA rings. The two-phase cytoplasm arrangement allows the bacterial cell to organize the central dogma activities, where (from the cell center to its periphery) DNA replicates and segregates, DNA is transcribed, nascent mRNA is handed over to ribosomes, mRNA is translated into proteins, and finally, the used mRNA is recycled into nucleotides at the inner membrane. The resulting information-action conveyor, with one activity naturally leading to the next one, explains the efficiency of prokaryotic cell design-even though its main intracellular transportation mode is free diffusion.
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Affiliation(s)
- Andrei Kuzminov
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
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2
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Tan K, Tse-Dinh YC. Variation of Structure and Cellular Functions of Type IA Topoisomerases across the Tree of Life. Cells 2024; 13:553. [PMID: 38534397 DOI: 10.3390/cells13060553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 03/12/2024] [Accepted: 03/19/2024] [Indexed: 03/28/2024] Open
Abstract
Topoisomerases regulate the topological state of cellular genomes to prevent impediments to vital cellular processes, including replication and transcription from suboptimal supercoiling of double-stranded DNA, and to untangle topological barriers generated as replication or recombination intermediates. The subfamily of type IA topoisomerases are the only topoisomerases that can alter the interlinking of both DNA and RNA. In this article, we provide a review of the mechanisms by which four highly conserved N-terminal protein domains fold into a toroidal structure, enabling cleavage and religation of a single strand of DNA or RNA. We also explore how these conserved domains can be combined with numerous non-conserved protein sequences located in the C-terminal domains to form a diverse range of type IA topoisomerases in Archaea, Bacteria, and Eukarya. There is at least one type IA topoisomerase present in nearly every free-living organism. The variation in C-terminal domain sequences and interacting partners such as helicases enable type IA topoisomerases to conduct important cellular functions that require the passage of nucleic acids through the break of a single-strand DNA or RNA that is held by the conserved N-terminal toroidal domains. In addition, this review will exam a range of human genetic disorders that have been linked to the malfunction of type IA topoisomerase.
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Affiliation(s)
- Kemin Tan
- Structural Biology Center, X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, 9700 S. Cass Avenue, Lemont, IL 60439, USA
| | - Yuk-Ching Tse-Dinh
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
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3
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Mishra S, Tewari H, Chaudhary R, S Misra H, Kota S. Differential cellular localization of DNA gyrase and topoisomerase IB in response to DNA damage in Deinococcus radiodurans. Extremophiles 2023; 28:7. [PMID: 38062175 DOI: 10.1007/s00792-023-01323-1] [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: 05/16/2023] [Accepted: 11/02/2023] [Indexed: 12/18/2023]
Abstract
Topoisomerases are crucial enzymes in genome maintenance that modulate the topological changes during DNA metabolism. Deinococcus radiodurans, a Gram-positive bacterium is characterized by its resistance to many abiotic stresses including gamma radiation. Its multipartite genome encodes both type I and type II topoisomerases. Time-lapse studies using fluorescently tagged topoisomerase IB (drTopoIB-RFP) and DNA gyrase (GyrA-RFP) were performed to check the dynamics and localization with respect to DNA repair and cell division under normal and post-irradiation growth conditions. Results suggested that TopoIB and DNA gyrase are mostly found on nucleoid, highly dynamic, and show growth phase-dependent subcellular localization. The drTopoIB-RFP was also present at peripheral and septum regions but does not co-localize with the cell division protein, drFtsZ. On the other hand, DNA gyrase co-localizes with PprA a pleiotropic protein involved in radioresistance, on the nucleoid during the post-irradiation recovery (PIR). The topoIB mutant was found to be sensitive to hydroxyurea treatment, and showed more accumulation of single-stranded DNA during the PIR, compared to the wild type suggesting its role in DNA replication stress. Together, these results suggest differential localization of drTopoIB-RFP and GyrA-RFP in D. radiodurans and their interaction with PprA protein, emphasizing the functional significance and role in radioresistance.
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Affiliation(s)
- Shruti Mishra
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400085, India
- Homi Bhabha National Institute, Mumbai, 400094, India
| | - Himani Tewari
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400085, India
- Homi Bhabha National Institute, Mumbai, 400094, India
| | - Reema Chaudhary
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400085, India
- National Centre for Microbial Resource, National Centre for Cell Science, Sai Trinity Complex, Sus Road, Pashan, Pune, 411021, India
| | - Hari S Misra
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400085, India
- Homi Bhabha National Institute, Mumbai, 400094, India
- Centre of Multidisciplinary Unit of Research On Translational Initiatives and School of Science, GITAM (Deemed to Be University), Gandhinagar, Rushikonda, Visakhapatnam, 530045, India
| | - Swathi Kota
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400085, India.
- Homi Bhabha National Institute, Mumbai, 400094, India.
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4
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García-López M, Hernández P, Megias D, Ferrándiz MJ, de la Campa AG. Physiologic and Transcriptomic Effects Triggered by Overexpression of Wild Type and Mutant DNA Topoisomerase I in Streptococcus pneumoniae. Int J Mol Sci 2023; 24:15800. [PMID: 37958782 PMCID: PMC10648598 DOI: 10.3390/ijms242115800] [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] [Revised: 10/20/2023] [Accepted: 10/25/2023] [Indexed: 11/15/2023] Open
Abstract
Topoisomerase I (TopoI) in Streptococcus pneumoniae, encoded by topA, is a suitable target for drug development. Seconeolitsine (SCN) is a new antibiotic that specifically blocks this enzyme. We obtained the topARA mutant, which encodes an enzyme less active than the wild type (topAWT) and more resistant to SCN inhibition. Likely due to the essentiality of TopoI, we were unable to replace the topAWT allele by the mutant topARA version. We compared the in vivo activity of TopoIRA and TopoIWT using regulated overexpression strains, whose genes were either under the control of a moderately (PZn) or a highly active promoter (PMal). Overproduction of TopoIRA impaired growth, increased SCN resistance and, in the presence of the gyrase inhibitor novobiocin (NOV), caused lower relaxation than TopoIWT. Differential transcriptomes were observed when the topAWT and topARA expression levels were increased about 5-fold. However, higher increases (10-15 times), produced a similar transcriptome, affecting about 52% of the genome, and correlating with a high DNA relaxation level with most responsive genes locating in topological domains. These results confirmed that TopoI is indeed the target of SCN in S. pneumoniae and show the important role of TopoI in global transcription, supporting its suitability as an antibiotic target.
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Affiliation(s)
- Miriam García-López
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain;
| | - Pablo Hernández
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain;
| | - Diego Megias
- Unidad de Microscopía Confocal, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain;
| | - María-José Ferrándiz
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain;
| | - Adela G. de la Campa
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain;
- Presidencia, Consejo Superior de Investigaciones Científicas, 28006 Madrid, Spain
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5
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Junier I, Ghobadpour E, Espeli O, Everaers R. DNA supercoiling in bacteria: state of play and challenges from a viewpoint of physics based modeling. Front Microbiol 2023; 14:1192831. [PMID: 37965550 PMCID: PMC10642903 DOI: 10.3389/fmicb.2023.1192831] [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: 03/23/2023] [Accepted: 09/25/2023] [Indexed: 11/16/2023] Open
Abstract
DNA supercoiling is central to many fundamental processes of living organisms. Its average level along the chromosome and over time reflects the dynamic equilibrium of opposite activities of topoisomerases, which are required to relax mechanical stresses that are inevitably produced during DNA replication and gene transcription. Supercoiling affects all scales of the spatio-temporal organization of bacterial DNA, from the base pair to the large scale chromosome conformation. Highlighted in vitro and in vivo in the 1960s and 1970s, respectively, the first physical models were proposed concomitantly in order to predict the deformation properties of the double helix. About fifteen years later, polymer physics models demonstrated on larger scales the plectonemic nature and the tree-like organization of supercoiled DNA. Since then, many works have tried to establish a better understanding of the multiple structuring and physiological properties of bacterial DNA in thermodynamic equilibrium and far from equilibrium. The purpose of this essay is to address upcoming challenges by thoroughly exploring the relevance, predictive capacity, and limitations of current physical models, with a specific focus on structural properties beyond the scale of the double helix. We discuss more particularly the problem of DNA conformations, the interplay between DNA supercoiling with gene transcription and DNA replication, its role on nucleoid formation and, finally, the problem of scaling up models. Our primary objective is to foster increased collaboration between physicists and biologists. To achieve this, we have reduced the respective jargon to a minimum and we provide some explanatory background material for the two communities.
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Affiliation(s)
- Ivan Junier
- CNRS, UMR 5525, VetAgro Sup, Grenoble INP, TIMC, Université Grenoble Alpes, Grenoble, France
| | - Elham Ghobadpour
- CNRS, UMR 5525, VetAgro Sup, Grenoble INP, TIMC, Université Grenoble Alpes, Grenoble, France
- École Normale Supérieure (ENS) de Lyon, CNRS, Laboratoire de Physique and Centre Blaise Pascal de l'ENS de Lyon, Lyon, France
| | - Olivier Espeli
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Ralf Everaers
- École Normale Supérieure (ENS) de Lyon, CNRS, Laboratoire de Physique and Centre Blaise Pascal de l'ENS de Lyon, Lyon, France
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6
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Boulas I, Bruno L, Rimsky S, Espeli O, Junier I, Rivoire O. Assessing in vivo the impact of gene context on transcription through DNA supercoiling. Nucleic Acids Res 2023; 51:9509-9521. [PMID: 37667073 PMCID: PMC10570042 DOI: 10.1093/nar/gkad688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 07/24/2023] [Accepted: 08/09/2023] [Indexed: 09/06/2023] Open
Abstract
Gene context can have significant impact on gene expression but is currently not integrated in quantitative models of gene regulation despite known biophysical principles and quantitative in vitro measurements. Conceptually, the simplest gene context consists of a single gene framed by two topological barriers, known as the twin transcriptional-loop model, which illustrates the interplay between transcription and DNA supercoiling. In vivo, DNA supercoiling is additionally modulated by topoisomerases, whose modus operandi remains to be quantified. Here, we bridge the gap between theory and in vivo properties by realizing in Escherichia coli the twin transcriptional-loop model and by measuring how gene expression varies with promoters and distances to the topological barriers. We find that gene expression depends on the distance to the upstream barrier but not to the downstream barrier, with a promoter-dependent intensity. We rationalize these findings with a first-principle biophysical model of DNA transcription. Our results are explained if TopoI and gyrase both act specifically, respectively upstream and downstream of the gene, with antagonistic effects of TopoI, which can repress initiation while facilitating elongation. Altogether, our work sets the foundations for a systematic and quantitative description of the impact of gene context on gene regulation.
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Affiliation(s)
- Ihab Boulas
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Lisa Bruno
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Sylvie Rimsky
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Olivier Espeli
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Ivan Junier
- Univ. Grenoble Alpes, CNRS, UMR 5525, VetAgro Sup, Grenoble INP, TIMC, 38000 Grenoble, France
| | - Olivier Rivoire
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, Paris, France
- Gulliver, ESPCI, CNRS, Université PSL, Paris, France
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Biswas P, Sengupta S, Nagaraja V. Evolution of YacG to safeguard DNA gyrase from external perturbation. Res Microbiol 2023; 174:104093. [PMID: 37343614 DOI: 10.1016/j.resmic.2023.104093] [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: 03/20/2023] [Revised: 06/10/2023] [Accepted: 06/14/2023] [Indexed: 06/23/2023]
Abstract
Cells have evolved strategies to safeguard their genome integrity. We describe a mechanism to counter double strand breaks in the chromosome that involves the protection of an essential housekeeping enzyme from external agents. YacG is a DNA gyrase inhibitory protein from Escherichia coli that protects the bacterium from the cytotoxic effects of catalytic inhibitors as well as cleavage-complex stabilizers of DNA gyrase. By virtue of blocking the primary DNA binding site of the enzyme, YacG prevents the accumulation of double strand breaks induced by gyrase poisons. It also enables the bacterium to resist the growth-inhibitory property of novobiocin. Gyrase poison-induced oxidative stress upregulates YacG production, probably as a cellular response to counter DNA damage. YacG-mediated protection of the genome is specific for gyrase targeting agents as the protection is not observed from the action of general DNA damaging agents. YacG also intensifies the transcription stress induced by rifampicin substantiating the importance of gyrase activity during transcription. Although essential for bacterial survival, DNA gyrase often gets entrapped by external inhibitors and poisons, resulting in cell death. The existence of YacG to specifically protect an essential housekeeping enzyme might be a strategy adopted by bacteria for competitive fitness advantage.
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Affiliation(s)
- Priti Biswas
- Department of Life Sciences, Presidency University Kolkata, 86/1 College Street, Kolkata-700073, India.
| | - Sugopa Sengupta
- Department of Life Sciences, Presidency University Kolkata, 86/1 College Street, Kolkata-700073, India.
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India; Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore-560064, India.
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Galvin CJ, Hobson M, Meng JX, Ierokomos A, Ivanov IE, Berger JM, Bryant Z. Single-molecule dynamics of DNA gyrase in evolutionarily distant bacteria Mycobacterium tuberculosis and Escherichia coli. J Biol Chem 2023; 299:103003. [PMID: 36775125 PMCID: PMC10130225 DOI: 10.1016/j.jbc.2023.103003] [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: 05/18/2022] [Revised: 02/06/2023] [Accepted: 02/07/2023] [Indexed: 02/12/2023] Open
Abstract
DNA gyrase is an essential nucleoprotein motor present in all bacteria and is a major target for antibiotic treatment of Mycobacterium tuberculosis (MTB) infection. Gyrase hydrolyzes ATP to add negative supercoils to DNA using a strand passage mechanism that has been investigated using biophysical and biochemical approaches. To analyze the dynamics of substeps leading to strand passage, single-molecule rotor bead tracking (RBT) has been used previously to follow real-time supercoiling and conformational transitions in Escherichia coli (EC) gyrase. However, RBT has not yet been applied to gyrase from other pathogenically relevant bacteria, and it is not known whether substeps are conserved across evolutionarily distant species. Here, we compare gyrase supercoiling dynamics between two evolutionarily distant bacterial species, MTB and EC. We used RBT to measure supercoiling rates, processivities, and the geometries and transition kinetics of conformational states of purified gyrase proteins in complex with DNA. Our results show that E. coli and MTB gyrases are both processive, with the MTB enzyme displaying velocities ∼5.5× slower than the EC enzyme. Compared with EC gyrase, MTB gyrase also more readily populates an intermediate state with DNA chirally wrapped around the enzyme, in both the presence and absence of ATP. Our substep measurements reveal common features in conformational states of EC and MTB gyrases interacting with DNA but also suggest differences in populations and transition rates that may reflect distinct cellular needs between these two species.
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Affiliation(s)
- Cooper J Galvin
- Program in Biophysics, Stanford University, Stanford, California, USA; Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Matthew Hobson
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | | - Athena Ierokomos
- Program in Biophysics, Stanford University, Stanford, California, USA; Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Ivan E Ivanov
- Department of Bioengineering, Stanford University, Stanford, California, USA; Department of Chemical Engineering, Stanford University, Stanford, California, USA
| | - James M Berger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Zev Bryant
- Program in Biophysics, Stanford University, Stanford, California, USA; Department of Bioengineering, Stanford University, Stanford, California, USA; Department of Structural Biology, Stanford University Medical Center, Stanford, California, USA.
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de Vasconcelos Junior AA, Tirado-Vélez JM, Martín-Galiano AJ, Megias D, Ferrándiz MJ, Hernández P, Amblar M, de la Campa AG. StaR Is a Positive Regulator of Topoisomerase I Activity Involved in Supercoiling Maintenance in Streptococcus pneumoniae. Int J Mol Sci 2023; 24:ijms24065973. [PMID: 36983048 PMCID: PMC10053502 DOI: 10.3390/ijms24065973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/16/2023] [Accepted: 03/18/2023] [Indexed: 03/30/2023] Open
Abstract
The DNA topoisomerases gyrase and topoisomerase I as well as the nucleoid-associated protein HU maintain supercoiling levels in Streptococcus pneumoniae, a main human pathogen. Here, we characterized, for the first time, a topoisomerase I regulator protein (StaR). In the presence of sub-inhibitory novobiocin concentrations, which inhibit gyrase activity, higher doubling times were observed in a strain lacking staR, and in two strains in which StaR was over-expressed either under the control of the ZnSO4-inducible PZn promoter (strain ΔstaRPZnstaR) or of the maltose-inducible PMal promoter (strain ΔstaRpLS1ROMstaR). These results suggest that StaR has a direct role in novobiocin susceptibility and that the StaR level needs to be maintained within a narrow range. Treatment of ΔstaRPZnstaR with inhibitory novobiocin concentrations resulted in a change of the negative DNA supercoiling density (σ) in vivo, which was higher in the absence of StaR (σ = -0.049) than when StaR was overproduced (σ = -0.045). We have located this protein in the nucleoid by using super-resolution confocal microscopy. Through in vitro activity assays, we demonstrated that StaR stimulates TopoI relaxation activity, while it has no effect on gyrase activity. Interaction between TopoI and StaR was detected both in vitro and in vivo by co-immunoprecipitation. No alteration of the transcriptome was associated with StaR amount variation. The results suggest that StaR is a new streptococcal nucleoid-associated protein that activates topoisomerase I activity by direct protein-protein interaction.
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Affiliation(s)
| | - Jose M Tirado-Vélez
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain
| | - Antonio J Martín-Galiano
- Unidades Centrales Científico-Técnicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain
| | - Diego Megias
- Unidad de Microscopía Confocal, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain
| | - María-José Ferrándiz
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain
| | - Pablo Hernández
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain
| | - Mónica Amblar
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain
| | - Adela G de la Campa
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain
- Presidencia, Consejo Superior de Investigaciones Científicas, 28006 Madrid, Spain
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García-López M, Megias D, Ferrándiz MJ, de la Campa AG. The balance between gyrase and topoisomerase I activities determines levels of supercoiling, nucleoid compaction, and viability in bacteria. Front Microbiol 2023; 13:1094692. [PMID: 36713152 PMCID: PMC9875019 DOI: 10.3389/fmicb.2022.1094692] [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: 11/10/2022] [Accepted: 12/23/2022] [Indexed: 01/13/2023] Open
Abstract
Two enzymes are responsible for maintaining supercoiling in the human pathogen Streptococcus pneumoniae, gyrase (GyrA2GyrB2) and topoisomerase I. To attain diverse levels of topoisomerase I (TopoI, encoded by topA), two isogenic strains derived from wild-type strain R6 were constructed: PZn topA, carrying an ectopic topA copy under the control of the ZnSO4-regulated PZn promoter and its derivative ΔtopAPZn topA, which carries a topA deletion at its native chromosomal location. We estimated the number of TopoI and GyrA molecules per cell by using Western-blot and CFUs counting, and correlated these values with supercoiling levels. Supercoiling was estimated in two ways. We used classical 2D-agarose gel electrophoresis of plasmid topoisomers to determine supercoiling density (σ) and we measured compaction of nucleoids using for the first time super-resolution confocal microscopy. Notably, we observed a good correlation between both supercoiling calculations. In R6, with σ = -0.057, the average number of GyrA molecules per cell (2,184) was higher than that of TopoI (1,432), being the GyrA:TopoI proportion of 1:0.65. In ΔtopAPZn topA, the number of TopoI molecules depended, as expected, on ZnSO4 concentration in the culture media, being the proportions of GyrA:TopoI molecules in 75, 150, and 300 μM ZnSO4 of 1:0.43, 1:0.47, and 1:0.63, respectively, which allowed normal supercoiling and growth. However, in the absence of ZnSO4, a higher GyrA:TopoI ratio (1:0.09) caused hyper-supercoiling (σ = -0.086) and lethality. Likewise, growth of ΔtopAPZn topA in the absence of ZnSO4 was restored when gyrase was inhibited with novobiocin, coincidentally with the resolution of hyper-supercoiling (σ change from -0.080 to -0.068). Given that TopoI is a monomer and two molecules of GyrA are present in the gyrase heterotetramer, the gyrase:TopoI enzymes proportion would be 1:1.30 (wild type R6) or of 1:1.26-0.86 (ΔtopAPZn topA under viable conditions). Higher proportions, such as 1:0.18 observed in ΔtopAPZn topA in the absence of ZnSO4 yielded to hyper-supercoiling and lethality. These results support a role of the equilibrium between gyrase and TopoI activities in supercoiling maintenance, nucleoid compaction, and viability. Our results shed new light on the mechanism of action of topoisomerase-targeting antibiotics, paving the way for the use of combination therapies.
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Affiliation(s)
- Míriam García-López
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Diego Megias
- Unidad de Microscopía Confocal, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - María-José Ferrándiz
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain,*Correspondence: María-José Ferrándiz, ✉
| | - Adela G. de la Campa
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain,Presidencia, Consejo Superior de Investigaciones Científicas, Madrid, Spain,Adela G. de la Campa, ✉
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11
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Dorman CJ. Variable DNA topology is an epigenetic generator of physiological heterogeneity in bacterial populations. Mol Microbiol 2023; 119:19-28. [PMID: 36565252 PMCID: PMC10108321 DOI: 10.1111/mmi.15014] [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: 10/28/2022] [Revised: 11/25/2022] [Accepted: 12/06/2022] [Indexed: 12/25/2022]
Abstract
Transcription is a noisy and stochastic process that produces sibling-to-sibling variations in physiology across a population of genetically identical cells. This pattern of diversity reflects, in part, the burst-like nature of transcription. Transcription bursting has many causes and a failure to remove the supercoils that accumulate in DNA during transcription elongation is an important contributor. Positive supercoiling of the DNA ahead of the transcription elongation complex can result in RNA polymerase stalling if this DNA topological roadblock is not removed. The relaxation of these positive supercoils is performed by the ATP-dependent type II topoisomerases DNA gyrase and topoisomerase IV. Interference with the action of these topoisomerases involving, inter alia, topoisomerase poisons, fluctuations in the [ATP]/[ADP] ratio, and/or the intervention of nucleoid-associated proteins with GapR-like or YejK-like activities, may have consequences for the smooth operation of the transcriptional machinery. Antibiotic-tolerant (but not resistant) persister cells are among the phenotypic outliers that may emerge. However, interference with type II topoisomerase activity can have much broader consequences, making it an important epigenetic driver of physiological diversity in the bacterial population.
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Affiliation(s)
- Charles J Dorman
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland
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12
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Behle A, Dietsch M, Goldschmidt L, Murugathas W, Berwanger L, Burmester J, Yao L, Brandt D, Busche T, Kalinowski J, Hudson E, Ebenhöh O, Axmann I, Machné R. Manipulation of topoisomerase expression inhibits cell division but not growth and reveals a distinctive promoter structure in Synechocystis. Nucleic Acids Res 2022; 50:12790-12808. [PMID: 36533444 PMCID: PMC9825172 DOI: 10.1093/nar/gkac1132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 11/03/2022] [Accepted: 11/10/2022] [Indexed: 12/23/2022] Open
Abstract
In cyanobacteria DNA supercoiling varies over the diurnal cycle and is integrated with temporal programs of transcription and replication. We manipulated DNA supercoiling in Synechocystis sp. PCC 6803 by CRISPRi-based knockdown of gyrase subunits and overexpression of topoisomerase I (TopoI). Cell division was blocked but cell growth continued in all strains. The small endogenous plasmids were only transiently relaxed, then became strongly supercoiled in the TopoI overexpression strain. Transcript abundances showed a pronounced 5'/3' gradient along transcription units, incl. the rRNA genes, in the gyrase knockdown strains. These observations are consistent with the basic tenets of the homeostasis and twin-domain models of supercoiling in bacteria. TopoI induction initially led to downregulation of G+C-rich and upregulation of A+T-rich genes. The transcriptional response quickly bifurcated into six groups which overlap with diurnally co-expressed gene groups. Each group shows distinct deviations from a common core promoter structure, where helically phased A-tracts are in phase with the transcription start site. Together, our data show that major co-expression groups (regulons) in Synechocystis all respond differentially to DNA supercoiling, and suggest to re-evaluate the long-standing question of the role of A-tracts in bacterial promoters.
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Affiliation(s)
| | | | - Louis Goldschmidt
- Institut f. Quantitative u. Theoretische Biologie, Heinrich-Heine Universität Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Wandana Murugathas
- Institut f. Synthetische Mikrobiologie, Heinrich-Heine Universität Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Lutz C Berwanger
- Institut f. Synthetische Mikrobiologie, Heinrich-Heine Universität Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Jonas Burmester
- Institut f. Synthetische Mikrobiologie, Heinrich-Heine Universität Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Lun Yao
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH – Royal Institute of Technology, Stockholm, Sweden
| | - David Brandt
- Centrum für Biotechnologie (CeBiTec), Universität Bielefeld, Universitätsstrasse 27, 33615 Bielefeld, Germany
| | - Tobias Busche
- Centrum für Biotechnologie (CeBiTec), Universität Bielefeld, Universitätsstrasse 27, 33615 Bielefeld, Germany
| | - Jörn Kalinowski
- Centrum für Biotechnologie (CeBiTec), Universität Bielefeld, Universitätsstrasse 27, 33615 Bielefeld, Germany
| | - Elton P Hudson
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH – Royal Institute of Technology, Stockholm, Sweden
| | - Oliver Ebenhöh
- Institut f. Quantitative u. Theoretische Biologie, Heinrich-Heine Universität Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany,Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Ilka M Axmann
- Institut f. Synthetische Mikrobiologie, Heinrich-Heine Universität Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Rainer Machné
- To whom correspondence should be addressed. Tel: +49 211 81 12923;
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13
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RNase HI Depletion Strongly Potentiates Cell Killing by Rifampicin in Mycobacteria. Antimicrob Agents Chemother 2022; 66:e0209121. [PMID: 36154174 DOI: 10.1128/aac.02091-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Multidrug-resistant (MDR) tuberculosis (TB) is defined by the resistance of Mycobacterium tuberculosis, the causative organism, to the first-line antibiotics rifampicin and isoniazid. Mitigating or reversing resistance to these drugs offers a means of preserving and extending their use in TB treatment. R-loops are RNA/DNA hybrids that are formed in the genome during transcription, and they can be lethal to the cell if not resolved. RNase HI is an enzyme that removes R-loops, and this activity is essential in M. tuberculosis: knockouts of rnhC, the gene encoding RNase HI, are nonviable. This essentiality makes it a candidate target for the development of new antibiotics. In the model organism Mycolicibacterium smegmatis, RNase HI activity is provided by two enzymes, RnhA and RnhC. We show that the partial depletion of RNase HI activity in M. smegmatis, by knocking out either of the genes encoding RnhA or RnhC, led to the accumulation of R-loops. The sensitivity of the knockout strains to the antibiotics moxifloxacin, streptomycin, and rifampicin was increased, the latter by a striking near 100-fold. We also show that R-loop accumulation accompanies partial transcriptional inhibition, suggesting a mechanistic basis for the synergy between RNase HI depletion and rifampicin. A model of how transcriptional inhibition can potentiate R-loop accumulation is presented. Finally, we identified four small molecules that inhibit recombinant RnhC activity and that also potentiated rifampicin activity in whole-cell assays against M. tuberculosis, supporting an on-target mode of action and providing the first step in developing a new class of antimycobacterial drug.
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14
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Pineau M, Martis B. S, Forquet R, Baude J, Villard C, Grand L, Popowycz F, Soulère L, Hommais F, Nasser W, Reverchon S, Meyer S. What is a supercoiling-sensitive gene? Insights from topoisomerase I inhibition in the Gram-negative bacterium Dickeya dadantii. Nucleic Acids Res 2022; 50:9149-9161. [PMID: 35950487 PMCID: PMC9458453 DOI: 10.1093/nar/gkac679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 07/04/2022] [Accepted: 07/27/2022] [Indexed: 12/24/2022] Open
Abstract
DNA supercoiling is an essential mechanism of bacterial chromosome compaction, whose level is mainly regulated by topoisomerase I and DNA gyrase. Inhibiting either of these enzymes with antibiotics leads to global supercoiling modifications and subsequent changes in global gene expression. In previous studies, genes responding to DNA relaxation induced by DNA gyrase inhibition were categorised as 'supercoiling-sensitive'. Here, we studied the opposite variation of DNA supercoiling in the phytopathogen Dickeya dadantii using the non-marketed antibiotic seconeolitsine. We showed that the drug is active against topoisomerase I from this species, and analysed the first transcriptomic response of a Gram-negative bacterium to topoisomerase I inhibition. We find that the responding genes essentially differ from those observed after DNA relaxation, and further depend on the growth phase. We characterised these genes at the functional level, and also detected distinct patterns in terms of expression level, spatial and orientational organisation along the chromosome. Altogether, these results highlight that the supercoiling-sensitivity is a complex feature, which depends on the action of specific topoisomerases, on the physiological conditions, and on their genomic context. Based on previous in vitro expression data of several promoters, we propose a qualitative model of SC-dependent regulation that accounts for many of the contrasting transcriptomic features observed after DNA gyrase or topoisomerase I inhibition.
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Affiliation(s)
- Maïwenn Pineau
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Shiny Martis B.
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Raphaël Forquet
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Jessica Baude
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Camille Villard
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Lucie Grand
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, 69622 Villeurbanne, France
| | - Florence Popowycz
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, 69622 Villeurbanne, France
| | - Laurent Soulère
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CPE Lyon, CNRS UMR 5246, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, 69622 Villeurbanne, France
| | - Florence Hommais
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - William Nasser
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Sylvie Reverchon
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Sam Meyer
- To whom correspondence should be addressed. Tel: +33 4 72 43 85 16;
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15
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Interaction between transcribing RNA polymerase and topoisomerase I prevents R-loop formation in E. coli. Nat Commun 2022; 13:4524. [PMID: 35927234 PMCID: PMC9352719 DOI: 10.1038/s41467-022-32106-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 07/15/2022] [Indexed: 12/30/2022] Open
Abstract
Bacterial topoisomerase I (TopoI) removes excessive negative supercoiling and is thought to relax DNA molecules during transcription, replication and other processes. Using ChIP-Seq, we show that TopoI of Escherichia coli (EcTopoI) is colocalized, genome-wide, with transcribing RNA polymerase (RNAP). Treatment with transcription elongation inhibitor rifampicin leads to EcTopoI relocation to promoter regions, where RNAP also accumulates. When a 14 kDa RNAP-binding EcTopoI C-terminal domain (CTD) is overexpressed, colocalization of EcTopoI and RNAP along the transcription units is reduced. Pull-down experiments directly show that the two enzymes interact in vivo. Using ChIP-Seq and Topo-Seq, we demonstrate that EcTopoI is enriched upstream (within up to 12-15 kb) of highly-active transcription units, indicating that EcTopoI relaxes negative supercoiling generated by transcription. Uncoupling of the RNAP:EcTopoI interaction by either overexpression of EcTopoI competitor (CTD or inactive EcTopoI Y319F mutant) or deletion of EcTopoI domains involved in the interaction is toxic for cells and leads to excessive negative plasmid supercoiling. Moreover, uncoupling of the RNAP:EcTopoI interaction leads to R-loops accumulation genome-wide, indicating that this interaction is required for prevention of R-loops formation. In E. coli, disruption of TopoI and RNAP interaction decreases cells viability and leads to hypernegative DNA supercoiling and R loops accumulation. TopoI and DNA gyrase bind around transcription units and TopoI recognizes cleavage sites by a specific motif and negative supercoiling.
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16
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McKie SJ, Desai P, Seol Y, Allen AM, Maxwell A, Neuman KC. Topoisomerase VI is a chirally-selective, preferential DNA decatenase. eLife 2022; 11:67021. [PMID: 35076393 PMCID: PMC8837201 DOI: 10.7554/elife.67021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 01/24/2022] [Indexed: 11/28/2022] Open
Abstract
DNA topoisomerase VI (topo VI) is a type IIB DNA topoisomerase found predominantly in archaea and some bacteria, but also in plants and algae. Since its discovery, topo VI has been proposed to be a DNA decatenase; however, robust evidence and a mechanism for its preferential decatenation activity was lacking. Using single-molecule magnetic tweezers measurements and supporting ensemble biochemistry, we demonstrate that Methanosarcina mazei topo VI preferentially unlinks, or decatenates DNA crossings, in comparison to relaxing supercoils, through a preference for certain DNA crossing geometries. In addition, topo VI demonstrates a significant increase in ATPase activity, DNA binding and rate of strand passage, with increasing DNA writhe, providing further evidence that topo VI is a DNA crossing sensor. Our study strongly suggests that topo VI has evolved an intrinsic preference for the unknotting and decatenation of interlinked chromosomes by sensing and preferentially unlinking DNA crossings with geometries close to 90°.
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Affiliation(s)
- Shannon J McKie
- Laboratory of Single Molecule Biophysics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
| | - Parth Desai
- Laboratory of Single Molecule Biophysics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
| | - Yeonee Seol
- Laboratory of Single Molecule Biophysics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
| | - Adam Mb Allen
- Department of Biochemistry and Metabolism, John Innes Centre, Norwich, United Kingdom
| | - Anthony Maxwell
- Department of Biochemistry and Metabolism, John Innes Centre, Norwich, United Kingdom
| | - Keir C Neuman
- Laboratory of Single Molecule Biophysics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
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17
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A Novel Spo11 Homologue Functions as a Positive Regulator in Cyst Differentiation in Giardia lamblia. Int J Mol Sci 2021; 22:ijms222111902. [PMID: 34769330 PMCID: PMC8584520 DOI: 10.3390/ijms222111902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 10/27/2021] [Accepted: 10/28/2021] [Indexed: 01/14/2023] Open
Abstract
Giardia lamblia persists in a dormant state with a protective cyst wall for transmission. It is incompletely known how three cyst wall proteins (CWPs) are coordinately synthesized during encystation. Meiotic recombination is required for sexual reproduction in animals, fungi, and plants. It is initiated by formation of double-stranded breaks by a topoisomerase-like Spo11. It has been shown that exchange of genetic material in the fused nuclei occurs during Giardia encystation, suggesting parasexual recombination processes of this protozoan. Giardia possesses an evolutionarily conserved Spo11 with typical domains for cleavage reaction and an upregulated expression pattern during encystation. In this study, we asked whether Spo11 can activate encystation process, like other topoisomerases we previously characterized. We found that Spo11 was capable of binding to both single-stranded and double-stranded DNA in vitro and that it could also bind to the cwp promoters in vivo as accessed in chromatin immunoprecipitation assays. Spo11 interacted with WRKY and MYB2 (named from myeloblastosis), transcription factors that can activate cwp gene expression during encystation. Interestingly, overexpression of Spo11 resulted in increased expression of cwp1-3 and myb2 genes and cyst formation. Mutation of the Tyr residue for the active site or two conserved residues corresponding to key DNA-binding residues for Arabidopsis Spo11 reduced the levels of cwp1-3 and myb2 gene expression and cyst formation. Targeted disruption of spo11 gene with CRISPR/Cas9 system led to a significant decrease in cwp1-3 and myb2 gene expression and cyst number. Our results suggest that Spo11 acts as a positive regulator for Giardia differentiation into cyst.
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18
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Fogg JM, Judge AK, Stricker E, Chan HL, Zechiedrich L. Supercoiling and looping promote DNA base accessibility and coordination among distant sites. Nat Commun 2021; 12:5683. [PMID: 34584096 PMCID: PMC8478907 DOI: 10.1038/s41467-021-25936-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 08/30/2021] [Indexed: 11/29/2022] Open
Abstract
DNA in cells is supercoiled and constrained into loops and this supercoiling and looping influence every aspect of DNA activity. We show here that negative supercoiling transmits mechanical stress along the DNA backbone to disrupt base pairing at specific distant sites. Cooperativity among distant sites localizes certain sequences to superhelical apices. Base pair disruption allows sharp bending at superhelical apices, which facilitates DNA writhing to relieve torsional strain. The coupling of these processes may help prevent extensive denaturation associated with genomic instability. Our results provide a model for how DNA can form short loops, which are required for many essential processes, and how cells may use DNA loops to position nicks to facilitate repair. Furthermore, our results reveal a complex interplay between site-specific disruptions to base pairing and the 3-D conformation of DNA, which influences how genomes are stored, replicated, transcribed, repaired, and many other aspects of DNA activity.
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Affiliation(s)
- Jonathan M Fogg
- Department of Molecular Virology and Microbiology, Houston, TX, USA
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Houston, TX, USA
- Department of Pharmacology and Chemical Biology, Houston, TX, USA
| | - Allison K Judge
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Houston, TX, USA
| | - Erik Stricker
- Department of Molecular Virology and Microbiology, Houston, TX, USA
| | - Hilda L Chan
- Graduate Program in Immunology and Microbiology, Houston, TX, USA
- Medical Scientist Training Program, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA
| | - Lynn Zechiedrich
- Department of Molecular Virology and Microbiology, Houston, TX, USA.
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Houston, TX, USA.
- Department of Pharmacology and Chemical Biology, Houston, TX, USA.
- Graduate Program in Immunology and Microbiology, Houston, TX, USA.
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19
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Hirsch J, Klostermeier D. What makes a type IIA topoisomerase a gyrase or a Topo IV? Nucleic Acids Res 2021; 49:6027-6042. [PMID: 33905522 PMCID: PMC8216471 DOI: 10.1093/nar/gkab270] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/26/2021] [Accepted: 04/01/2021] [Indexed: 12/14/2022] Open
Abstract
Type IIA topoisomerases catalyze a variety of different reactions: eukaryotic topoisomerase II relaxes DNA in an ATP-dependent reaction, whereas the bacterial representatives gyrase and topoisomerase IV (Topo IV) preferentially introduce negative supercoils into DNA (gyrase) or decatenate DNA (Topo IV). Gyrase and Topo IV perform separate, dedicated tasks during replication: gyrase removes positive supercoils in front, Topo IV removes pre-catenanes behind the replication fork. Despite their well-separated cellular functions, gyrase and Topo IV have an overlapping activity spectrum: gyrase is also able to catalyze DNA decatenation, although less efficiently than Topo IV. The balance between supercoiling and decatenation activities is different for gyrases from different organisms. Both enzymes consist of a conserved topoisomerase core and structurally divergent C-terminal domains (CTDs). Deletion of the entire CTD, mutation of a conserved motif and even by just a single point mutation within the CTD converts gyrase into a Topo IV-like enzyme, implicating the CTDs as the major determinant for function. Here, we summarize the structural and mechanistic features that make a type IIA topoisomerase a gyrase or a Topo IV, and discuss the implications for type IIA topoisomerase evolution.
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Affiliation(s)
- Jana Hirsch
- University of Muenster, Institute for Physical Chemistry, Corrensstrasse 30, 48149 Muenster, Germany
| | - Dagmar Klostermeier
- University of Muenster, Institute for Physical Chemistry, Corrensstrasse 30, 48149 Muenster, Germany
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20
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Ferrándiz MJ, Hernández P, de la Campa AG. Genome-wide proximity between RNA polymerase and DNA topoisomerase I supports transcription in Streptococcus pneumoniae. PLoS Genet 2021; 17:e1009542. [PMID: 33930020 PMCID: PMC8115823 DOI: 10.1371/journal.pgen.1009542] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 05/12/2021] [Accepted: 04/10/2021] [Indexed: 02/02/2023] Open
Abstract
Streptococcus pneumoniae is a major cause of disease and death that develops resistance to multiple antibiotics. DNA topoisomerase I (TopoI) is a novel pneumococcal drug target. TopoI is the sole type-I pneumococcal topoisomerase that regulates supercoiling homeostasis in this bacterium. In this study, a direct in vitro interaction between TopoI and RNA polymerase (RNAP) was detected by surface plasmon resonance. To understand the interplay between transcription and supercoiling regulation in vivo, genome-wide association of RNAP and TopoI was studied by ChIP-Seq. RNAP and TopoI were enriched at the promoters of 435 and 356 genes, respectively. Higher levels of expression were consistently measured in those genes whose promoters recruit both RNAP and TopoI, in contrast with those enriched in only one of them. Both enzymes occupied a narrow region close to the ATG codon. In addition, RNAP displayed a regular distribution throughout the coding regions. Likewise, the summits of peaks called with MACS tool, mapped around the ATG codon in both cases. However, RNAP showed a broader distribution towards ATG-downstream positions. Remarkably, inhibition of RNAP with rifampicin prevented the localization of TopoI at promoters and, vice versa, inhibition of TopoI with seconeolitsine prevented the binding of RNAP to promoters. This indicates a functional interplay between RNAP and TopoI. To determine the molecular factors responsible for RNAP and TopoI co-recruitment, we looked for DNA sequence motifs. We identified a motif corresponding to a -10-extended promoter for TopoI and for RNAP. Furthermore, RNAP was preferentially recruited to genes co-directionally oriented with replication, while TopoI was more abundant in head-on genes. TopoI was located in the intergenic regions of divergent genes pairs, near the promoter of the head-on gene of the pair. These results suggest a role for TopoI in the formation/stability of the RNAP-DNA complex at the promoter and during transcript elongation. Streptococcus pneumoniae is a main cause of pneumonia, meningitis and sepsis. Antibiotic resistance in this bacterium has spread worldwide, compromising medical treatment. Therefore, the development of new drugs directed to novel targets is necessary. DNA topology is essential for the regulation of replication and gene expression. Topology is regulated and maintained by DNA topoisomerases, carrying out nicking-closing reactions. Type I and type II topoisomerases act on single-stranded and double-stranded DNA, respectively. Although type II topoisomerases are the target of clinically used antibiotics, there are no clinical antibiotics directed against type I topoisomerases. Seconeolitsine, a new drug targeting topoisomerase I, is effective against bacteria that have a single type I topoisomerase, such as Streptococcus pneumoniae and Mycobacterium tuberculosis. In this report, we studied the role of topoisomerase I in transcription. We found that topoisomerase I and RNA polymerase physically interact in vitro and co-localize at gene promoters in vivo. Binding of each of these enzymes to promoters was prevented by the specific inhibition of the other enzyme, supporting a role for topoisomerase I in RNA polymerase transcription.
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Affiliation(s)
- María-José Ferrándiz
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Pablo Hernández
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Adela G. de la Campa
- Unidad de Genética Bacteriana, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- Presidencia, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- * E-mail:
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21
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Pozdeev G, Mogre A, Dorman CJ. Consequences of producing DNA gyrase from a synthetic gyrBA operon in Salmonella enterica serovar Typhimurium. Mol Microbiol 2021; 115:1410-1429. [PMID: 33539568 PMCID: PMC8359277 DOI: 10.1111/mmi.14689] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 12/17/2022]
Abstract
DNA gyrase is an essential type II topoisomerase that is composed of two subunits, GyrA and GyrB, and has an A2B2 structure. Although the A and B subunits are required in equal proportions to form DNA gyrase, the gyrA and gyrB genes that encode them in Salmonella (and in many other bacteria) are at separate locations on the chromosome, are under separate transcriptional control, and are present in different copy numbers in rapidly growing bacteria. In wild‐type Salmonella, gyrA is near the chromosome's replication terminus, while gyrB is near the origin. We generated a synthetic gyrBA operon at the oriC‐proximal location of gyrB to test the significance of the gyrase gene position for Salmonella physiology. Although the strain producing gyrase from an operon had a modest alteration to its DNA supercoiling set points, most housekeeping functions were unaffected. However, its SPI‐2 virulence genes were expressed at a reduced level and its survival was reduced in macrophage. Our data reveal that the horizontally acquired SPI‐2 genes have a greater sensitivity to disturbance of DNA topology than the core genome and we discuss its significance in the context of Salmonella genome evolution and the gyrA and gyrB gene arrangements found in other bacteria.
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Affiliation(s)
- German Pozdeev
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland
| | - Aalap Mogre
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland
| | - Charles J Dorman
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland
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22
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McKie SJ, Neuman KC, Maxwell A. DNA topoisomerases: Advances in understanding of cellular roles and multi-protein complexes via structure-function analysis. Bioessays 2021; 43:e2000286. [PMID: 33480441 PMCID: PMC7614492 DOI: 10.1002/bies.202000286] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/06/2020] [Accepted: 12/17/2020] [Indexed: 12/15/2022]
Abstract
DNA topoisomerases, capable of manipulating DNA topology, are ubiquitous and indispensable for cellular survival due to the numerous roles they play during DNA metabolism. As we review here, current structural approaches have revealed unprecedented insights into the complex DNA-topoisomerase interaction and strand passage mechanism, helping to advance our understanding of their activities in vivo. This has been complemented by single-molecule techniques, which have facilitated the detailed dissection of the various topoisomerase reactions. Recent work has also revealed the importance of topoisomerase interactions with accessory proteins and other DNA-associated proteins, supporting the idea that they often function as part of multi-enzyme assemblies in vivo. In addition, novel topoisomerases have been identified and explored, such as topo VIII and Mini-A. These new findings are advancing our understanding of DNA-related processes and the vital functions topos fulfil, demonstrating their indispensability in virtually every aspect of DNA metabolism.
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Affiliation(s)
- Shannon J McKie
- Department Biological Chemistry, John Innes Centre, Norwich, UK.,Laboratory of Single Molecule Biophysics, NHLBI, Bethesda, Maryland, USA
| | - Keir C Neuman
- Laboratory of Single Molecule Biophysics, NHLBI, Bethesda, Maryland, USA
| | - Anthony Maxwell
- Department Biological Chemistry, John Innes Centre, Norwich, UK
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Sutormin DA, Galivondzhyan AK, Polkhovskiy AV, Kamalyan SO, Severinov KV, Dubiley SA. Diversity and Functions of Type II Topoisomerases. Acta Naturae 2021; 13:59-75. [PMID: 33959387 PMCID: PMC8084294 DOI: 10.32607/actanaturae.11058] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 10/09/2020] [Indexed: 11/29/2022] Open
Abstract
The DNA double helix provides a simple and elegant way to store and copy genetic information. However, the processes requiring the DNA helix strands separation, such as transcription and replication, induce a topological side-effect - supercoiling of the molecule. Topoisomerases comprise a specific group of enzymes that disentangle the topological challenges associated with DNA supercoiling. They relax DNA supercoils and resolve catenanes and knots. Here, we review the catalytic cycles, evolution, diversity, and functional roles of type II topoisomerases in organisms from all domains of life, as well as viruses and other mobile genetic elements.
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Affiliation(s)
- D. A. Sutormin
- Institute of Gene Biology RAS, Moscow, 119334 Russia
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
| | - A. K. Galivondzhyan
- Lomonosov Moscow State University, Moscow, 119991 Russia
- Institute of Molecular Genetics RAS, Moscow, 123182 Russia
| | - A. V. Polkhovskiy
- Institute of Gene Biology RAS, Moscow, 119334 Russia
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
| | - S. O. Kamalyan
- Institute of Gene Biology RAS, Moscow, 119334 Russia
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
| | - K. V. Severinov
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
- Centre for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology RAS, Moscow, 119334 Russia
- Waksman Institute for Microbiology, Piscataway, New Jersey, 08854 USA
| | - S. A. Dubiley
- Institute of Gene Biology RAS, Moscow, 119334 Russia
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
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de Wet TJ, Winkler KR, Mhlanga M, Mizrahi V, Warner DF. Arrayed CRISPRi and quantitative imaging describe the morphotypic landscape of essential mycobacterial genes. eLife 2020; 9:e60083. [PMID: 33155979 PMCID: PMC7647400 DOI: 10.7554/elife.60083] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 10/03/2020] [Indexed: 12/11/2022] Open
Abstract
Mycobacterium tuberculosis possesses a large number of genes of unknown or predicted function, undermining fundamental understanding of pathogenicity and drug susceptibility. To address this challenge, we developed a high-throughput functional genomics approach combining inducible CRISPR-interference and image-based analyses of morphological features and sub-cellular chromosomal localizations in the related non-pathogen, M. smegmatis. Applying automated imaging and analysis to 263 essential gene knockdown mutants in an arrayed library, we derive robust, quantitative descriptions of bacillary morphologies consequent on gene silencing. Leveraging statistical-learning, we demonstrate that functionally related genes cluster by morphotypic similarity and that this information can be used to inform investigations of gene function. Exploiting this observation, we infer the existence of a mycobacterial restriction-modification system, and identify filamentation as a defining mycobacterial response to histidine starvation. Our results support the application of large-scale image-based analyses for mycobacterial functional genomics, simultaneously establishing the utility of this approach for drug mechanism-of-action studies.
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Affiliation(s)
- Timothy J de Wet
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Kristy R Winkler
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Musa Mhlanga
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Department of Integrative Biomedical Sciences, University of Cape TownCape TownSouth Africa
| | - Valerie Mizrahi
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Wellcome Centre for Infectious Diseases Research in Africa, University of Cape TownCape TownSouth Africa
| | - Digby F Warner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Wellcome Centre for Infectious Diseases Research in Africa, University of Cape TownCape TownSouth Africa
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25
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Dasgupta T, Ferdous S, Tse-Dinh YC. Mechanism of Type IA Topoisomerases. Molecules 2020; 25:E4769. [PMID: 33080770 PMCID: PMC7587558 DOI: 10.3390/molecules25204769] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/12/2020] [Accepted: 10/15/2020] [Indexed: 11/16/2022] Open
Abstract
Topoisomerases in the type IA subfamily can catalyze change in topology for both DNA and RNA substrates. A type IA topoisomerase may have been present in a last universal common ancestor (LUCA) with an RNA genome. Type IA topoisomerases have since evolved to catalyze the resolution of topological barriers encountered by genomes that require the passing of nucleic acid strand(s) through a break on a single DNA or RNA strand. Here, based on available structural and biochemical data, we discuss how a type IA topoisomerase may recognize and bind single-stranded DNA or RNA to initiate its required catalytic function. Active site residues assist in the nucleophilic attack of a phosphodiester bond between two nucleotides to form a covalent intermediate with a 5'-phosphotyrosine linkage to the cleaved nucleic acid. A divalent ion interaction helps to position the 3'-hydroxyl group at the precise location required for the cleaved phosphodiester bond to be rejoined following the passage of another nucleic acid strand through the break. In addition to type IA topoisomerase structures observed by X-ray crystallography, we now have evidence from biophysical studies for the dynamic conformations that are required for type IA topoisomerases to catalyze the change in the topology of the nucleic acid substrates.
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Affiliation(s)
- Tumpa Dasgupta
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA; (T.D.); (S.F.)
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
- Biochemistry PhD Program, Florida International University, Miami, FL 33199, USA
| | - Shomita Ferdous
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA; (T.D.); (S.F.)
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
- Biochemistry PhD Program, Florida International University, Miami, FL 33199, USA
| | - Yuk-Ching Tse-Dinh
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA; (T.D.); (S.F.)
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
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26
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Kota S, Chaudhary R, Mishra S, Misra HS. Topoisomerase IB interacts with genome segregation proteins and is involved in multipartite genome maintenance in Deinococcus radiodurans. Microbiol Res 2020; 242:126609. [PMID: 33059113 DOI: 10.1016/j.micres.2020.126609] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 09/18/2020] [Accepted: 09/19/2020] [Indexed: 10/23/2022]
Abstract
Deinococcus radiodurans, an extremophile, resistant to many abiotic stresses including ionizing radiation, has 2 type I topoisomerases (drTopo IA and drTopo IB) and one type II topoisomerase (DNA gyrase). The role of drTopo IB in guanine quadruplex DNA (G4 DNA) metabolism was demonstrated earlier in vitro. Here, we report that D. radiodurans cells lacking drTopo IB (ΔtopoIB) show sensitivity to G4 DNA binding drug (NMM) under normal growth conditions. The activity of G4 motif containing promoters like mutL and recQ was reduced in the presence of NMM in mutant cells. In mutant, the percentage of anucleate cells was more while the copy number of genome elements were less as compared to wild type. Protein-protein interaction studies showed that drTopo IB interacts with genome segregation and DNA replication initiation (DnaA) proteins. The typical patterns of cellular localization of GFP-PprA were affected in the mutant cells. Microscopic examination of D. radiodurans cells expressing drTopo IB-RFP showed its localization on nucleoid forming a streak parallel to the old division septum and perpendicular to newly formed septum. These results together suggest the role of drTopo IB in genome maintenance in this bacterium.
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Affiliation(s)
- Swathi Kota
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400085, India; Life Sciences, Homi Bhabha National Institute, Mumbai, 400094, India.
| | - Reema Chaudhary
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400085, India; Life Sciences, Homi Bhabha National Institute, Mumbai, 400094, India
| | - Shruti Mishra
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400085, India; Life Sciences, Homi Bhabha National Institute, Mumbai, 400094, India
| | - Hari S Misra
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400085, India; Life Sciences, Homi Bhabha National Institute, Mumbai, 400094, India.
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27
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Rani P, Kalladi SM, Bansia H, Rao S, Jha RK, Jain P, Bhaduri T, Nagaraja V. A Type IA DNA/RNA Topoisomerase with RNA Hydrolysis Activity Participates in Ribosomal RNA Processing. J Mol Biol 2020; 432:5614-5631. [DOI: 10.1016/j.jmb.2020.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 08/13/2020] [Accepted: 08/14/2020] [Indexed: 01/19/2023]
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28
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Supercoiling, R-loops, Replication and the Functions of Bacterial Type 1A Topoisomerases. Genes (Basel) 2020; 11:genes11030249. [PMID: 32120891 PMCID: PMC7140829 DOI: 10.3390/genes11030249] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/19/2020] [Accepted: 02/26/2020] [Indexed: 12/26/2022] Open
Abstract
Type 1A topoisomerases (topos) are the only topos that bind single-stranded DNA and the only ones found in all cells of the three domains of life. Two subfamilies, topo I and topo III, are present in bacteria. Topo I, found in all of them, relaxes negative supercoiling, while topo III acts as a decatenase in replication. However, recent results suggest that they can also act as back-up for each other. Because they are ubiquitous, type 1A enzymes are expected to be essential for cell viability. Single topA (topo I) and topB (topo III) null mutants of Escherichia coli are viable, but for topA only with compensatory mutations. Double topA topB null mutants were initially believed to be non-viable. However, in two independent studies, results of next generation sequencing (NGS) have recently shown that double topA topB null mutants of Bacillus subtilis and E. coli are viable when they carry parC parE gene amplifications. These genes encode the two subunits of topo IV, the main cellular decatenase. Here, we discuss the essential functions of bacterial type 1A topos in the context of this observation and new results showing their involvement in preventing unregulated replication from R-loops.
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29
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Sun CH, Weng SC, Wu JH, Tung SY, Su LH, Lin MH, Lee GA. DNA topoisomerase IIIβ promotes cyst generation by inducing cyst wall protein gene expression in Giardia lamblia. Open Biol 2020; 10:190228. [PMID: 32019477 PMCID: PMC7058931 DOI: 10.1098/rsob.190228] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Giardia lamblia causes waterborne diarrhoea by transmission of infective cysts. Three cyst wall proteins are highly expressed in a concerted manner during encystation of trophozoites into cysts. However, their gene regulatory mechanism is still largely unknown. DNA topoisomerases control topological homeostasis of genomic DNA during replication, transcription and chromosome segregation. They are involved in a variety of cellular processes including cell cycle, cell proliferation and differentiation, so they may be valuable drug targets. Giardia lamblia possesses a type IA DNA topoisomerase (TOP3β) with similarity to the mammalian topoisomerase IIIβ. We found that TOP3β was upregulated during encystation and it possessed DNA-binding and cleavage activity. TOP3β can bind to the cwp promoters in vivo using norfloxacin-mediated topoisomerase immunoprecipitation assays. We also found TOP3β can interact with MYB2, a transcription factor involved in the coordinate expression of cwp1-3 genes during encystation. Interestingly, overexpression of TOP3β increased expression of cwp1-3 and myb2 genes and cyst formation. Microarray analysis confirmed upregulation of cwp1-3 and myb2 genes by TOP3β. Mutation of the catalytically important Tyr residue, deletion of C-terminal zinc ribbon domain or further deletion of partial catalytic core domain reduced the levels of cleavage activity, cwp1-3 and myb2 gene expression, and cyst formation. Interestingly, some of these mutant proteins were mis-localized to cytoplasm. Using a CRISPR/Cas9 system for targeted disruption of top3β gene, we found a significant decrease in cwp1-3 and myb2 gene expression and cyst number. Our results suggest that TOP3β may be functionally conserved, and involved in inducing Giardia cyst formation.
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Affiliation(s)
- Chin-Hung Sun
- Department of Tropical Medicine and Parasitology, College of Medicine, National Taiwan University, Taipei 100, Taiwan, Republic of China
| | - Shih-Che Weng
- Department of Tropical Medicine and Parasitology, College of Medicine, National Taiwan University, Taipei 100, Taiwan, Republic of China
| | - Jui-Hsuan Wu
- Department of Tropical Medicine and Parasitology, College of Medicine, National Taiwan University, Taipei 100, Taiwan, Republic of China
| | - Szu-Yu Tung
- Department of Tropical Medicine and Parasitology, College of Medicine, National Taiwan University, Taipei 100, Taiwan, Republic of China
| | - Li-Hsin Su
- Department of Tropical Medicine and Parasitology, College of Medicine, National Taiwan University, Taipei 100, Taiwan, Republic of China
| | - Meng-Hsuan Lin
- Department of Tropical Medicine and Parasitology, College of Medicine, National Taiwan University, Taipei 100, Taiwan, Republic of China
| | - Gilbert Aaron Lee
- Department of Medical Research, Taipei Medical University Hospital, Taipei, Taiwan, Republic of China
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30
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Mapping DNA Topoisomerase Binding and Cleavage Genome Wide Using Next-Generation Sequencing Techniques. Genes (Basel) 2020; 11:genes11010092. [PMID: 31941152 PMCID: PMC7017377 DOI: 10.3390/genes11010092] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/08/2020] [Accepted: 01/10/2020] [Indexed: 01/02/2023] Open
Abstract
Next-generation sequencing (NGS) platforms have been adapted to generate genome-wide maps and sequence context of binding and cleavage of DNA topoisomerases (topos). Continuous refinements of these techniques have resulted in the acquisition of data with unprecedented depth and resolution, which has shed new light on in vivo topo behavior. Topos regulate DNA topology through the formation of reversible single- or double-stranded DNA breaks. Topo activity is critical for DNA metabolism in general, and in particular to support transcription and replication. However, the binding and activity of topos over the genome in vivo was difficult to study until the advent of NGS. Over and above traditional chromatin immunoprecipitation (ChIP)-seq approaches that probe protein binding, the unique formation of covalent protein–DNA linkages associated with DNA cleavage by topos affords the ability to probe cleavage and, by extension, activity over the genome. NGS platforms have facilitated genome-wide studies mapping the behavior of topos in vivo, how the behavior varies among species and how inhibitors affect cleavage. Many NGS approaches achieve nucleotide resolution of topo binding and cleavage sites, imparting an extent of information not previously attainable. We review the development of NGS approaches to probe topo interactions over the genome in vivo and highlight general conclusions and quandaries that have arisen from this rapidly advancing field of topoisomerase research.
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31
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Couturier M, Gadelle D, Forterre P, Nadal M, Garnier F. The reverse gyrase TopR1 is responsible for the homeostatic control of DNA supercoiling in the hyperthermophilic archaeon Sulfolobus solfataricus. Mol Microbiol 2019; 113:356-368. [PMID: 31713907 DOI: 10.1111/mmi.14424] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 11/06/2019] [Accepted: 11/10/2019] [Indexed: 11/28/2022]
Abstract
Maintaining an appropriate DNA topology with DNA-based processes (DNA replication, transcription and recombination) is crucial for all three domains of life. In bacteria, the homeostatic regulation for controlling DNA supercoiling relies on antagonistic activities of two DNA topoisomerases, TopoI and gyrase. In hyperthermophilic crenarchaea, the presence of such a regulatory system is suggested as two DNA topoisomerases, TopoVI and reverse gyrase, catalyze antagonistic activities. To test this hypothesis, we estimated and compared the number of the TopoVI with that of the two reverse gyrases, TopR1 and TopR2, in Sulfolobus solfataricus cells maintained either at 80 or at 88°C, or reciprocally shifted from one temperature to the other. From the three DNA topoisomerases, TopR1 is the only one exhibiting significant quantitative variations in response to the up- and down-shifts. In addition, the corresponding intrinsic activities of these three DNA topoisomerases were tested in vitro at both temperatures. Although temperature modulates the three DNA topoisomerases activities, TopR1 is the sole topoisomerase able to function at high temperature. Altogether, results presented in this study demonstrate, for the first time, that the DNA topological state of a crenarchaeon is regulated via a homeostatic control, which is mainly mediated by the fine-tuning of TopR1.
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Affiliation(s)
- Mohea Couturier
- Institut de Génétique et Microbiologie, UMR 8621 CNRS-Université Paris-Sud, Orsay Cedex, France
| | - Danièle Gadelle
- Institut de Génétique et Microbiologie, UMR 8621 CNRS-Université Paris-Sud, Orsay Cedex, France
| | - Patrick Forterre
- Institut de Génétique et Microbiologie, UMR 8621 CNRS-Université Paris-Sud, Orsay Cedex, France
| | - Marc Nadal
- Institut de Génétique et Microbiologie, UMR 8621 CNRS-Université Paris-Sud, Orsay Cedex, France.,Institut Jacques Monod, UMR 8621 CNRS-Université Paris Diderot, Paris Cedex 13, France
| | - Florence Garnier
- Institut de Génétique et Microbiologie, UMR 8621 CNRS-Université Paris-Sud, Orsay Cedex, France.,Institut Jacques Monod, UMR 8621 CNRS-Université Paris Diderot, Paris Cedex 13, France.,Biology Department, Université Versailles St-Quentin, Versailles, France
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32
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Rani P, Nagaraja V. Genome-wide mapping of Topoisomerase I activity sites reveal its role in chromosome segregation. Nucleic Acids Res 2019; 47:1416-1427. [PMID: 30566665 PMCID: PMC6379724 DOI: 10.1093/nar/gky1271] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/30/2018] [Accepted: 12/13/2018] [Indexed: 11/13/2022] Open
Abstract
DNA Topoisomerase I (TopoI) in eubacteria is the principle DNA relaxase, belonging to Type 1A group. The enzyme from Mycobacterium smegmatis is essential for cell survival and distinct from other eubacteria in having several unusual characteristics. To understand genome-wide TopoI engagements in vivo, functional sites were mapped by employing a poisonous variant of the enzyme and a newly discovered inhibitor, both of which arrest the enzyme activity after the first transestrification reaction, thereby leading to the accumulation of protein-DNA covalent complexes. The cleavage sites are subsets of TopoI binding sites, implying that TopoI recruitment does not necessarily lead to DNA cleavage in vivo. The cleavage protection conferred by nucleoid associated proteins in vitro suggest a similar possibility in vivo. Co-localization of binding and cleavage sites of the enzyme on transcription units, implying that both TopoI recruitment and function are associated with active transcription. Attenuation of the cleavage upon Rifampicin treatment confirms the close connection between transcription and TopoI action. Notably, TopoI is inactive upstream of the Transcription start site (TSS) and activated following transcription initiation. The binding of TopoI at the Ter region, and the DNA cleavage at the Ter indicates TopoI involvement in chromosome segregation, substantiated by its catenation and decatenation activities.
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Affiliation(s)
- Phoolwanti Rani
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.,Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
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33
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Cook PR, Marenduzzo D. Transcription-driven genome organization: a model for chromosome structure and the regulation of gene expression tested through simulations. Nucleic Acids Res 2019; 46:9895-9906. [PMID: 30239812 PMCID: PMC6212781 DOI: 10.1093/nar/gky763] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 09/14/2018] [Indexed: 12/29/2022] Open
Abstract
Current models for the folding of the human genome see a hierarchy stretching down from chromosome territories, through A/B compartments and topologically-associating domains (TADs), to contact domains stabilized by cohesin and CTCF. However, molecular mechanisms underlying this folding, and the way folding affects transcriptional activity, remain obscure. Here we review physical principles driving proteins bound to long polymers into clusters surrounded by loops, and present a parsimonious yet comprehensive model for the way the organization determines function. We argue that clusters of active RNA polymerases and their transcription factors are major architectural features; then, contact domains, TADs and compartments just reflect one or more loops and clusters. We suggest tethering a gene close to a cluster containing appropriate factors—a transcription factory—increases the firing frequency, and offer solutions to many current puzzles concerning the actions of enhancers, super-enhancers, boundaries and eQTLs (expression quantitative trait loci). As a result, the activity of any gene is directly influenced by the activity of other transcription units around it in 3D space, and this is supported by Brownian-dynamics simulations of transcription factors binding to cognate sites on long polymers.
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Affiliation(s)
- Peter R Cook
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Davide Marenduzzo
- SUPA, School of Physics, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, UK
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34
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Martis B S, Forquet R, Reverchon S, Nasser W, Meyer S. DNA Supercoiling: an Ancestral Regulator of Gene Expression in Pathogenic Bacteria? Comput Struct Biotechnol J 2019; 17:1047-1055. [PMID: 31452857 PMCID: PMC6700405 DOI: 10.1016/j.csbj.2019.07.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/17/2019] [Accepted: 07/24/2019] [Indexed: 12/28/2022] Open
Abstract
DNA supercoiling acts as a global and ancestral regulator of bacterial gene expression. In this review, we advocate that it plays a pivotal role in host-pathogen interactions by transducing environmental signals to the bacterial chromosome and coordinating its transcriptional response. We present available evidence that DNA supercoiling is modulated by environmental stress conditions relevant to the infection process according to ancestral mechanisms, in zoopathogens as well as phytopathogens. We review the results of transcriptomics studies obtained in widely distant bacterial species, showing that such structural transitions of the chromosome are associated to a complex transcriptional response affecting a large fraction of the genome. Mechanisms and computational models of the transcriptional regulation by DNA supercoiling are then discussed, involving both basal interactions of RNA Polymerase with promoter DNA, and more specific interactions with regulatory proteins. A final part is specifically focused on the regulation of virulence genes within pathogenicity islands of several pathogenic bacterial species.
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Affiliation(s)
- Shiny Martis B
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
| | - Raphaël Forquet
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
| | - Sylvie Reverchon
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
| | - William Nasser
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
| | - Sam Meyer
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 11 avenue Jean Capelle, 69621 Villeurbanne, France
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35
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Dorman CJ. DNA supercoiling and transcription in bacteria: a two-way street. BMC Mol Cell Biol 2019; 20:26. [PMID: 31319794 PMCID: PMC6639932 DOI: 10.1186/s12860-019-0211-6] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/09/2019] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The processes of DNA supercoiling and transcription are interdependent because the movement of a transcription elongation complex simultaneously induces under- and overwinding of the DNA duplex and because the initiation, elongation and termination steps of transcription are all sensitive to the topological state of the DNA. RESULTS Policing of the local and global supercoiling of DNA by topoisomerases helps to sustain the major DNA-based transactions by eliminating barriers to the movement of transcription complexes and replisomes. Recent data from whole-genome and single-molecule studies have provided new insights into how interactions between transcription and the supercoiling of DNA influence the architecture of the chromosome and how they create cell-to-cell diversity at the level of gene expression through transcription bursting. CONCLUSIONS These insights into fundamental molecular processes reveal mechanisms by which bacteria can prevail in unpredictable and often hostile environments by becoming unpredictable themselves.
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Affiliation(s)
- Charles J Dorman
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland.
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36
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El Houdaigui B, Forquet R, Hindré T, Schneider D, Nasser W, Reverchon S, Meyer S. Bacterial genome architecture shapes global transcriptional regulation by DNA supercoiling. Nucleic Acids Res 2019; 47:5648-5657. [PMID: 31216038 PMCID: PMC6582348 DOI: 10.1093/nar/gkz300] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/15/2019] [Accepted: 04/16/2019] [Indexed: 01/20/2023] Open
Abstract
DNA supercoiling acts as a global transcriptional regulator in bacteria, that plays an important role in adapting their expression programme to environmental changes, but for which no quantitative or even qualitative regulatory model is available. Here, we focus on spatial supercoiling heterogeneities caused by the transcription process itself, which strongly contribute to this regulation mode. We propose a new mechanistic modeling of the transcription-supercoiling dynamical coupling along a genome, which allows simulating and quantitatively reproducing in vitro and in vivo transcription assays, and highlights the role of genes' local orientation in their supercoiling sensitivity. Consistently with predictions, we show that chromosomal relaxation artificially induced by gyrase inhibitors selectively activates convergent genes in several enterobacteria, while conversely, an increase in DNA supercoiling naturally selected in a long-term evolution experiment with Escherichia coli favours divergent genes. Simulations show that these global expression responses to changes in DNA supercoiling result from fundamental mechanical constraints imposed by transcription, independently from more specific regulation of each promoter. These constraints underpin a significant and predictable contribution to the complex rules by which bacteria use DNA supercoiling as a global but fine-tuned transcriptional regulator.
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Affiliation(s)
- Bilal El Houdaigui
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Raphaël Forquet
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Thomas Hindré
- Université Grenoble-Alpes, CNRS, Grenoble INP, TIMC-IMAG, 38000 Grenoble, France
| | - Dominique Schneider
- Université Grenoble-Alpes, CNRS, Grenoble INP, TIMC-IMAG, 38000 Grenoble, France
| | - William Nasser
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Sylvie Reverchon
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
| | - Sam Meyer
- Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS UMR5240, Laboratoire de Microbiologie, Adaptation et Pathogénie, 69621 Villeurbanne, France
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Gibson EG, Bax B, Chan PF, Osheroff N. Mechanistic and Structural Basis for the Actions of the Antibacterial Gepotidacin against Staphylococcus aureus Gyrase. ACS Infect Dis 2019; 5:570-581. [PMID: 30757898 DOI: 10.1021/acsinfecdis.8b00315] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gepotidacin is a first-in-class triazaacenaphthylene novel bacterial topoisomerase inhibitor (NBTI). The compound has successfully completed phase II trials for the treatment of acute bacterial skin/skin structure infections and for the treatment of uncomplicated urogenital gonorrhea. It also displays robust in vitro activity against a range of wild-type and fluoroquinolone-resistant bacteria. Due to the clinical promise of gepotidacin, a detailed understanding of its interactions with its antibacterial targets is essential. Thus, we characterized the mechanism of action of gepotidacin against Staphylococcus aureus gyrase. Gepotidacin was a potent inhibitor of gyrase-catalyzed DNA supercoiling (IC50 ≈ 0.047 μM) and relaxation of positively supercoiled substrates (IC50 ≈ 0.6 μM). Unlike fluoroquinolones, which induce primarily double-stranded DNA breaks, gepotidacin induced high levels of gyrase-mediated single-stranded breaks. No double-stranded breaks were observed even at high gepotidacin concentration, long cleavage times, or in the presence of ATP. Moreover, gepotidacin suppressed the formation of double-stranded breaks. Gepotidacin formed gyrase-DNA cleavage complexes that were stable for >4 h. In vitro competition suggests that gyrase binding by gepotidacin and fluoroquinolones are mutually exclusive. Finally, we determined crystal structures of gepotidacin with the S. aureus gyrase core fusion truncate with nicked (2.31 Å resolution) or intact (uncleaved) DNA (2.37 Å resolution). In both cases, a single gepotidacin molecule was bound midway between the two scissile DNA bonds and in a pocket between the two GyrA subunits. A comparison of the two structures demonstrates conformational flexibility within the central linker of gepotidacin, which may contribute to the activity of the compound.
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Affiliation(s)
| | - Ben Bax
- Medicines Discovery Institute, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, United Kingdom
| | - Pan F. Chan
- Infectious Diseases Discovery, GlaxoSmithKline, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, United States
| | - Neil Osheroff
- VA Tennessee Valley Healthcare System, 1310 24th Avenue S., Nashville, Tennessee 37212, United States
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38
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Sutormin D, Rubanova N, Logacheva M, Ghilarov D, Severinov K. Single-nucleotide-resolution mapping of DNA gyrase cleavage sites across the Escherichia coli genome. Nucleic Acids Res 2019; 47:1373-1388. [PMID: 30517674 PMCID: PMC6379681 DOI: 10.1093/nar/gky1222] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 11/19/2018] [Accepted: 11/23/2018] [Indexed: 12/31/2022] Open
Abstract
An important antibiotic target, DNA gyrase is an essential bacterial enzyme that introduces negative supercoils into DNA and relaxes positive supercoils accumulating in front of moving DNA and RNA polymerases. By altering the superhelical density, gyrase may regulate expression of bacterial genes. The information about how gyrase is distributed along genomic DNA and whether its distribution is affected by drugs is scarce. During catalysis, gyrase cleaves both DNA strands forming a covalently bound intermediate. By exploiting the ability of several topoisomerase poisons to stabilize this intermediate we developed a ChIP-Seq-based approach to locate, with single nucleotide resolution, DNA gyrase cleavage sites (GCSs) throughout the Escherichia coli genome. We identified an extended gyrase binding motif with phased 10-bp G/C content variation, indicating that bending ability of DNA contributes to gyrase binding. We also found that GCSs are enriched in extended regions located downstream of highly transcribed operons. Transcription inhibition leads to redistribution of gyrase suggesting that the enrichment is functionally significant. Our method can be applied for precise mapping of prokaryotic and eukaryotic type II topoisomerases cleavage sites in a variety of organisms and paves the way for future studies of various topoisomerase inhibitors.
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Affiliation(s)
- Dmitry Sutormin
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, 143026 Moscow, Russia
- Department of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Natalia Rubanova
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, 143026 Moscow, Russia
| | - Maria Logacheva
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, 143026 Moscow, Russia
| | - Dmitry Ghilarov
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, 143026 Moscow, Russia
- Malopolska Centre of Biotechnology, Jagiellonian University, 30387 Cracow, Poland
| | - Konstantin Severinov
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, 143026 Moscow, Russia
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
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39
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Datta C, Jha RK, Ahmed W, Ganguly S, Ghosh S, Nagaraja V. Physical and functional interaction between nucleoid-associated proteins HU and Lsr2 of Mycobacterium tuberculosis: altered DNA binding and gene regulation. Mol Microbiol 2019; 111:981-994. [PMID: 30633392 DOI: 10.1111/mmi.14202] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/06/2019] [Indexed: 12/15/2022]
Abstract
Nucleoid-associated proteins (NAPs) in bacteria contribute to key activities such as DNA compaction, chromosome organization and regulation of gene expression. HU and Lsr2 are two principal NAPs in Mycobacterium tuberculosis (Mtb). HU is essential for Mtb survival and is one of the most abundant NAPs. It differs from other eubacterial HU proteins in having a long, flexible lysine- and arginine-rich carboxy-terminal domain. Lsr2 of Mtb is the functional analogue of the bacterial NAP commonly called H-NS. Lsr2 binds to and regulates expression of A/T-rich portions of the otherwise G/C-rich mycobacterial chromosome. Here, we demonstrate that HU and Lsr2 interact to form a complex. The interaction occurs primarily through the flexible carboxy-terminal domain of HU and the acidic amino-terminal domain of Lsr2. The resulting complex, upon binding to DNA, forms thick nucleoprotein rods, in contrast to the DNA bridging seen with Lsr2 and the DNA compaction seen with HU. Furthermore, transcription assays indicate that the HU-Lsr2 complex is a regulator of gene expression. This physical and functional interaction between two NAPs, which has not been reported previously, is likely to be important for DNA organization and gene expression in Mtb and perhaps other bacterial species.
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Affiliation(s)
- Chandreyee Datta
- Department of Microbiology and Cell Biology, Indian Institute of Science, C.V. Raman Avenue, Bangalore, 560012, India
| | - Rajiv Kumar Jha
- Department of Microbiology and Cell Biology, Indian Institute of Science, C.V. Raman Avenue, Bangalore, 560012, India
| | - Wareed Ahmed
- Department of Microbiology and Cell Biology, Indian Institute of Science, C.V. Raman Avenue, Bangalore, 560012, India
| | - Sohini Ganguly
- Department of Microbiology and Cell Biology, Indian Institute of Science, C.V. Raman Avenue, Bangalore, 560012, India
| | - Soumitra Ghosh
- Department of Microbiology and Cell Biology, Indian Institute of Science, C.V. Raman Avenue, Bangalore, 560012, India
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, C.V. Raman Avenue, Bangalore, 560012, India.,Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, 560064, India
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40
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Guha S, Udupa S, Ahmed W, Nagaraja V. Rewired Downregulation of DNA Gyrase Impacts Cell Division, Expression of Topology Modulators, and Transcription in Mycobacterium smegmatis. J Mol Biol 2018; 430:4986-5001. [PMID: 30316784 DOI: 10.1016/j.jmb.2018.10.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 09/22/2018] [Accepted: 10/02/2018] [Indexed: 10/28/2022]
Abstract
DNA gyrase, essential for DNA replication and transcription, has traditionally been studied in vivo by treatments that inhibit the enzyme activity. Due to its indispensable function, gyrA and gyrB deletions cannot be generated. The coumarin inhibitors of gyrase induce the supercoiling-sensitive gyrase promoter by a mechanism termed relaxation-stimulated transcription. Hence, to study the effect of sustained reduction in gyrase levels, a conditional-knockdown strain was generated in Mycobacterium smegmatis such that gyrase expression was controlled by a supercoiling non-responsive regulatory circuit. Decreasing intracellular gyrase protein levels beyond 50% affected cell growth. Reduced gyrase levels in the reprogrammed gyr operon caused chromosome relaxation, diffuse nucleoid structure, cell elongation, and altered gene expression. The key cell division protein, ftsZ, was severely reduced in the elongated cells, indicating a link between gyrase and cell division. Low levels of gyrase resulted in low compensatory expression of topoisomerase I and elevated expression of topology modulators hupB and lsr2. Altered supercoiling due to gyrase depletion caused corresponding changes in the RNA polymerase density on transcription units leading to their altered transcription. The enhanced susceptibility of the knockdown strain to anti-tubercular drugs suggests its utility for screening new molecules that may act synergistically with gyrase inhibitors.
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Affiliation(s)
- Sarmistha Guha
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Shubha Udupa
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Wareed Ahmed
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India; Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India.
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41
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Neale HC, Jackson RW, Preston GM, Arnold DL. Supercoiling of an excised genomic island represses effector gene expression to prevent activation of host resistance. Mol Microbiol 2018; 110:444-454. [PMID: 30152900 PMCID: PMC6220960 DOI: 10.1111/mmi.14111] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2018] [Indexed: 01/18/2023]
Abstract
The plant pathogen Pseudomonas syringae pv. phaseolicola, which causes halo blight disease of beans, contains a 106 kb genomic island PPHGI‐1. PPHGI‐1 carries a gene, avrPphB, which encodes an effector protein that triggers a resistance response in certain bean cultivars. Previous studies have shown that when PPHGI‐1 is excised from the bacterial chromosome, avrPphB is downregulated and therefore the pathogen avoids triggering the host’s defence mechanism. Here, we investigate whether the downregulation of avrPphB is caused by the supercoiling of PPHGI‐1. We also investigate the effect of a PPHGI‐1‐encoded type 1A topoisomerase, TopB3, on island stability and bacterial pathogenicity in the plant. Supercoiling inhibitors significantly increased the expression of avrPphB but did not affect the excision of PPHGI‐1. An insertional mutant of topB3 displayed an increase in avrPphB expression and an increase in PPHGI‐1 excision as well as reduced population growth in resistant and susceptible cultivars of bean. These results suggest an important role for topoisomerases in the maintenance and stability of a bacterial‐encoded genomic island and demonstrate that supercoiling is involved in the downregulation of an effector gene once the island has been excised, allowing the pathogen to prevent further activation of the host defence response.
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Affiliation(s)
- Helen C Neale
- Centre for Research in Bioscience, Faculty of Health and Applied Sciences, The University of the West of England, Frenchay Campus, Bristol, BS16 1QY, UK
| | - Robert W Jackson
- School of Biological Sciences, University of Reading, Reading, RG6 6UR, UK
| | - Gail M Preston
- Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, UK
| | - Dawn L Arnold
- Centre for Research in Bioscience, Faculty of Health and Applied Sciences, The University of the West of England, Frenchay Campus, Bristol, BS16 1QY, UK
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42
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Mori G, Orena BS, Franch C, Mitchenall LA, Godbole AA, Rodrigues L, Aguilar-Pérez C, Zemanová J, Huszár S, Forbak M, Lane TR, Sabbah M, Deboosere N, Frita R, Vandeputte A, Hoffmann E, Russo R, Connell N, Veilleux C, Jha RK, Kumar P, Freundlich JS, Brodin P, Aínsa JA, Nagaraja V, Maxwell A, Mikušová K, Pasca MR, Ekins S. The EU approved antimalarial pyronaridine shows antitubercular activity and synergy with rifampicin, targeting RNA polymerase. Tuberculosis (Edinb) 2018; 112:98-109. [PMID: 30205975 DOI: 10.1016/j.tube.2018.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 08/03/2018] [Accepted: 08/05/2018] [Indexed: 12/19/2022]
Abstract
The search for compounds with biological activity for many diseases is turning increasingly to drug repurposing. In this study, we have focused on the European Union-approved antimalarial pyronaridine which was found to have in vitro activity against Mycobacterium tuberculosis (MIC 5 μg/mL). In macromolecular synthesis assays, pyronaridine resulted in a severe decrease in incorporation of 14C-uracil and 14C-leucine similar to the effect of rifampicin, a known inhibitor of M. tuberculosis RNA polymerase. Surprisingly, the co-administration of pyronaridine (2.5 μg/ml) and rifampicin resulted in in vitro synergy with an MIC 0.0019-0.0009 μg/mL. This was mirrored in a THP-1 macrophage infection model, with a 16-fold MIC reduction for rifampicin when the two compounds were co-administered versus rifampicin alone. Docking pyronaridine in M. tuberculosis RNA polymerase suggested the potential for it to bind outside of the RNA polymerase rifampicin binding pocket. Pyronaridine was also found to have activity against a M. tuberculosis clinical isolate resistant to rifampicin, and when combined with rifampicin (10% MIC) was able to inhibit M. tuberculosis RNA polymerase in vitro. All these findings, and in particular the synergistic behavior with the antitubercular rifampicin, inhibition of RNA polymerase in combination in vitro and its current use as a treatment for malaria, may suggest that pyronaridine could also be used as an adjunct for treatment against M. tuberculosis infection. Future studies will test potential for in vivo synergy, clinical utility and attempt to develop pyronaridine analogs with improved potency against M. tuberculosis RNA polymerase when combined with rifampicin.
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Affiliation(s)
- Giorgia Mori
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, 27100 Pavia, Italy
| | - Beatrice Silvia Orena
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, 27100 Pavia, Italy
| | - Clara Franch
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Lesley A Mitchenall
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Adwait Anand Godbole
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Liliana Rodrigues
- Departamento de Microbiología, Facultad de Medicina, and BIFI, Universidad de Zaragoza, and IIS-Aragón, 50009 Zaragoza, Spain; CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Spain; Fundación ARAID, Zaragoza, Spain
| | - Clara Aguilar-Pérez
- Departamento de Microbiología, Facultad de Medicina, and BIFI, Universidad de Zaragoza, and IIS-Aragón, 50009 Zaragoza, Spain; CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Spain
| | - Júlia Zemanová
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 84215, Bratislava, Slovakia
| | - Stanislav Huszár
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 84215, Bratislava, Slovakia
| | - Martin Forbak
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 84215, Bratislava, Slovakia
| | - Thomas R Lane
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, NC 27606, USA
| | - Mohamad Sabbah
- Department of Chemistry, University of Cambridge, Lensfield Rd, Cambridge, CB2 1EW, UK
| | - Nathalie Deboosere
- Univ Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, 1 rue du Professeur Calmette, 59000 Lille, France
| | - Rosangela Frita
- Univ Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, 1 rue du Professeur Calmette, 59000 Lille, France
| | - Alexandre Vandeputte
- Univ Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, 1 rue du Professeur Calmette, 59000 Lille, France
| | - Eik Hoffmann
- Univ Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, 1 rue du Professeur Calmette, 59000 Lille, France
| | - Riccardo Russo
- Division of Infectious Disease, Department of Medicine and the Ruy V. Lourenço Center for the Study of Emerging and Re-emerging Pathogens, Rutgers University - New Jersey Medical School, Newark, NJ 07103, USA
| | - Nancy Connell
- Division of Infectious Disease, Department of Medicine and the Ruy V. Lourenço Center for the Study of Emerging and Re-emerging Pathogens, Rutgers University - New Jersey Medical School, Newark, NJ 07103, USA
| | - Courtney Veilleux
- Division of Infectious Disease, Department of Medicine and the Ruy V. Lourenço Center for the Study of Emerging and Re-emerging Pathogens, Rutgers University - New Jersey Medical School, Newark, NJ 07103, USA
| | - Rajiv K Jha
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Pradeep Kumar
- Division of Infectious Disease, Department of Medicine and the Ruy V. Lourenço Center for the Study of Emerging and Re-emerging Pathogens, Rutgers University - New Jersey Medical School, Newark, NJ 07103, USA
| | - Joel S Freundlich
- Division of Infectious Disease, Department of Medicine and the Ruy V. Lourenço Center for the Study of Emerging and Re-emerging Pathogens, Rutgers University - New Jersey Medical School, Newark, NJ 07103, USA; Department of Pharmacology, Physiology, and Neuroscience, Rutgers University - New Jersey Medical School, Newark, NJ, 07103, USA
| | - Priscille Brodin
- Univ Lille, CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, 1 rue du Professeur Calmette, 59000 Lille, France
| | - Jose Antonio Aínsa
- Departamento de Microbiología, Facultad de Medicina, and BIFI, Universidad de Zaragoza, and IIS-Aragón, 50009 Zaragoza, Spain; CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Spain
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India; Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Anthony Maxwell
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Katarína Mikušová
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 84215, Bratislava, Slovakia
| | - Maria Rosalia Pasca
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, 27100 Pavia, Italy
| | - Sean Ekins
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, NC 27606, USA; Collaborative Drug Discovery, 1633 Bayshore Highway, Suite 342, Burlingame, CA 94403, USA.
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Klostermeier D. Why Two? On the Role of (A-)Symmetry in Negative Supercoiling of DNA by Gyrase. Int J Mol Sci 2018; 19:E1489. [PMID: 29772727 PMCID: PMC5983639 DOI: 10.3390/ijms19051489] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/09/2018] [Accepted: 05/12/2018] [Indexed: 11/17/2022] Open
Abstract
Gyrase is a type IIA topoisomerase that catalyzes negative supercoiling of DNA. The enzyme consists of two GyrA and two GyrB subunits. It is believed to introduce negative supercoils into DNA by converting a positive DNA node into a negative node through strand passage: First, it cleaves both DNA strands of a double-stranded DNA, termed the G-segment, and then it passes a second segment of the same DNA molecule, termed the T-segment, through the gap created. As a two-fold symmetric enzyme, gyrase contains two copies of all elements that are key for the supercoiling reaction: The GyrB subunits provide two active sites for ATP binding and hydrolysis. The GyrA subunits contain two C-terminal domains (CTDs) for DNA binding and wrapping to stabilize the positive DNA node, and two catalytic tyrosines for DNA cleavage. While the presence of two catalytic tyrosines has been ascribed to the necessity of cleaving both strands of the G-segment to enable strand passage, the role of the two ATP hydrolysis events and of the two CTDs has been less clear. This review summarizes recent results on the role of these duplicate elements for individual steps of the supercoiling reaction, and discusses the implications for the mechanism of DNA supercoiling.
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Affiliation(s)
- Dagmar Klostermeier
- Institute for Physical Chemistry, University of Muenster, Corrensstrasse 30, 48149 Muenster, Germany.
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Ashley RE, Blower TR, Berger JM, Osheroff N. Recognition of DNA Supercoil Geometry by Mycobacterium tuberculosis Gyrase. Biochemistry 2017; 56:5440-5448. [PMID: 28921956 PMCID: PMC5637011 DOI: 10.1021/acs.biochem.7b00681] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
![]()
Mycobacterium
tuberculosis encodes only a single
type II topoisomerase, gyrase. As a result, this enzyme likely carries
out the cellular functions normally performed by canonical gyrase
and topoisomerase IV, both in front of and behind the replication
fork. In addition, it is the sole target for quinolone antibacterials
in this species. Because quinolone-induced DNA strand breaks generated
on positively supercoiled DNA ahead of replication forks and transcription
complexes are most likely to result in permanent genomic damage, the
actions of M. tuberculosis gyrase on positively supercoiled
DNA were investigated. Results indicate that the enzyme acts rapidly
on overwound DNA and removes positive supercoils much faster than
it introduces negative supercoils into relaxed DNA. Canonical gyrase
and topoisomerase IV distinguish supercoil handedness differently
during the DNA cleavage reaction: while gyrase maintains lower levels
of cleavage complexes on overwound DNA, topoisomerase IV maintains
similar levels of cleavage complexes on both over- and underwound
substrates. M. tuberculosis gyrase maintained lower
levels of cleavage complexes on positively supercoiled DNA in the
absence and presence of quinolone-based drugs. By retaining this important
feature of canonical gyrase, the dual function M. tuberculosis type II enzyme remains a safe enzyme to act in front of replication
forks and transcription complexes. Finally, the N-terminal gate region
of the enzyme appears to be necessary to distinguish supercoil handedness
during DNA cleavage, suggesting that the capture of the transport
segment may influence how gyrase maintains cleavage complexes on substrates
with different topological states.
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Affiliation(s)
| | - Tim R Blower
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine , Baltimore, Maryland 21205-2185, United States
| | - James M Berger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine , Baltimore, Maryland 21205-2185, United States
| | - Neil Osheroff
- VA Tennessee Valley Healthcare System , Nashville, Tennessee 37212, United States
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45
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Banda S, Cao N, Tse-Dinh YC. Distinct Mechanism Evolved for Mycobacterial RNA Polymerase and Topoisomerase I Protein-Protein Interaction. J Mol Biol 2017; 429:2931-2942. [PMID: 28843989 DOI: 10.1016/j.jmb.2017.08.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/14/2017] [Accepted: 08/19/2017] [Indexed: 01/01/2023]
Abstract
We report here a distinct mechanism of interaction between topoisomerase I and RNA polymerase in Mycobacterium tuberculosis and Mycobacterium smegmatis that has evolved independently from the previously characterized interaction between bacterial topoisomerase I and RNA polymerase. Bacterial DNA topoisomerase I is responsible for preventing the hyper-negative supercoiling of genomic DNA. The association of topoisomerase I with RNA polymerase during transcription elongation could efficiently relieve transcription-driven negative supercoiling. Our results demonstrate a direct physical interaction between the C-terminal domains of topoisomerase I (TopoI-CTDs) and the β' subunit of RNA polymerase of M. smegmatis in the absence of DNA. The TopoI-CTDs in mycobacteria are evolutionarily unrelated in amino acid sequence and three-dimensional structure to the TopoI-CTD found in the majority of bacterial species outside Actinobacteria, including Escherichia coli. The functional interaction between topoisomerase I and RNA polymerase has evolved independently in mycobacteria and E. coli, with distinctively different structural elements of TopoI-CTD utilized for this protein-protein interaction. Zinc ribbon motifs in E. coli TopoI-CTD are involved in the interaction with RNA polymerase. For M. smegmatis TopoI-CTD, a 27-amino-acid tail that is rich in basic residues at the C-terminal end is responsible for the interaction with RNA polymerase. Overexpression of recombinant TopoI-CTD in M. smegmatis competed with the endogenous topoisomerase I for protein-protein interactions with RNA polymerase. The TopoI-CTD overexpression resulted in decreased survival following treatment with antibiotics and hydrogen peroxide, supporting the importance of the protein-protein interaction between topoisomerase I and RNA polymerase during stress response of mycobacteria.
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Affiliation(s)
- Srikanth Banda
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA; Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Nan Cao
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA; Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Yuk-Ching Tse-Dinh
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA; Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA.
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