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Muchová K, Pospíšil J, Kalocsaiová E, Chromiková Z, Žarnovičanová S, Šanderová H, Krásný L, Barák I. Spatio-temporal control of asymmetric septum positioning during sporulation in Bacillus subtilis. J Biol Chem 2024; 300:107339. [PMID: 38705388 PMCID: PMC11154705 DOI: 10.1016/j.jbc.2024.107339] [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: 03/19/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 05/07/2024] Open
Abstract
During sporulation, Bacillus subtilis forms an asymmetric septum, dividing the cell into two compartments, a mother cell and a forespore. The site of asymmetric septation is linked to the membrane where FtsZ and SpoIIE initiate the formation of the Z-ring and the E-ring, respectively. These rings then serve as a scaffold for the other cell division and peptidoglycan synthesizing proteins needed to build the septum. However, despite decades of research, not enough is known about how the asymmetric septation site is determined. Here, we identified and characterized the interaction between SpoIIE and RefZ. We show that these two proteins transiently colocalize during the early stages of asymmetric septum formation when RefZ localizes primarily from the mother cell side of the septum. We propose that these proteins and their interplay with the spatial organization of the chromosome play a role in controlling asymmetric septum positioning.
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Affiliation(s)
- Katarína Muchová
- Department of Microbial Genetics, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Jiří Pospíšil
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Evelína Kalocsaiová
- Department of Microbial Genetics, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Zuzana Chromiková
- Department of Microbial Genetics, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Silvia Žarnovičanová
- Department of Microbial Genetics, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Hana Šanderová
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Libor Krásný
- Laboratory of Microbial Genetics and Gene Expression, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic.
| | - Imrich Barák
- Department of Microbial Genetics, Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia.
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2
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Serrano M, Martins D, Henriques AO. Clostridioides difficile Sporulation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1435:273-314. [PMID: 38175480 DOI: 10.1007/978-3-031-42108-2_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Some members of the Firmicutes phylum, including many members of the human gut microbiota, are able to differentiate a dormant and highly resistant cell type, the endospore (hereinafter spore for simplicity). Spore-formers can colonize virtually any habitat and, because of their resistance to a wide variety of physical and chemical insults, spores can remain viable in the environment for long periods of time. In the anaerobic enteric pathogen Clostridioides difficile the aetiologic agent is the oxygen-resistant spore, while the toxins produced by actively growing cells are the main cause of the disease symptoms. Here, we review the regulatory circuits that govern entry into sporulation. We also cover the role of spores in the infectious cycle of C. difficile in relation to spore structure and function and the main control points along spore morphogenesis.
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Affiliation(s)
- Mónica Serrano
- Instituto de Tecnologia Química e Biológica António Xavier, Oeiras, Portugal.
| | - Diogo Martins
- Instituto de Tecnologia Química e Biológica António Xavier, Oeiras, Portugal
| | - Adriano O Henriques
- Instituto de Tecnologia Química e Biológica António Xavier, Oeiras, Portugal
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3
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Cardiolipin-Containing Lipid Membranes Attract the Bacterial Cell Division Protein DivIVA. Int J Mol Sci 2021; 22:ijms22158350. [PMID: 34361115 PMCID: PMC8348161 DOI: 10.3390/ijms22158350] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 07/28/2021] [Accepted: 08/01/2021] [Indexed: 02/04/2023] Open
Abstract
DivIVA is a protein initially identified as a spatial regulator of cell division in the model organism Bacillus subtilis, but its homologues are present in many other Gram-positive bacteria, including Clostridia species. Besides its role as topological regulator of the Min system during bacterial cell division, DivIVA is involved in chromosome segregation during sporulation, genetic competence, and cell wall synthesis. DivIVA localizes to regions of high membrane curvature, such as the cell poles and cell division site, where it recruits distinct binding partners. Previously, it was suggested that negative curvature sensing is the main mechanism by which DivIVA binds to these specific regions. Here, we show that Clostridioides difficile DivIVA binds preferably to membranes containing negatively charged phospholipids, especially cardiolipin. Strikingly, we observed that upon binding, DivIVA modifies the lipid distribution and induces changes to lipid bilayers containing cardiolipin. Our observations indicate that DivIVA might play a more complex and so far unknown active role during the formation of the cell division septal membrane.
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Ramm B, Heermann T, Schwille P. The E. coli MinCDE system in the regulation of protein patterns and gradients. Cell Mol Life Sci 2019; 76:4245-4273. [PMID: 31317204 PMCID: PMC6803595 DOI: 10.1007/s00018-019-03218-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/27/2019] [Accepted: 07/02/2019] [Indexed: 12/22/2022]
Abstract
Molecular self-organziation, also regarded as pattern formation, is crucial for the correct distribution of cellular content. The processes leading to spatiotemporal patterns often involve a multitude of molecules interacting in complex networks, so that only very few cellular pattern-forming systems can be regarded as well understood. Due to its compositional simplicity, the Escherichia coli MinCDE system has, thus, become a paradigm for protein pattern formation. This biological reaction diffusion system spatiotemporally positions the division machinery in E. coli and is closely related to ParA-type ATPases involved in most aspects of spatiotemporal organization in bacteria. The ATPase MinD and the ATPase-activating protein MinE self-organize on the membrane as a reaction matrix. In vivo, these two proteins typically oscillate from pole-to-pole, while in vitro they can form a variety of distinct patterns. MinC is a passenger protein supposedly operating as a downstream cue of the system, coupling it to the division machinery. The MinCDE system has helped to extract not only the principles underlying intracellular patterns, but also how they are shaped by cellular boundaries. Moreover, it serves as a model to investigate how patterns can confer information through specific and non-specific interactions with other molecules. Here, we review how the three Min proteins self-organize to form patterns, their response to geometric boundaries, and how these patterns can in turn induce patterns of other molecules, focusing primarily on experimental approaches and developments.
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Affiliation(s)
- Beatrice Ramm
- Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152, Martinsried, Germany
| | - Tamara Heermann
- Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152, Martinsried, Germany
| | - Petra Schwille
- Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152, Martinsried, Germany.
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A Strongly Fluorescing Anaerobic Reporter and Protein-Tagging System for Clostridium Organisms Based on the Fluorescence-Activating and Absorption-Shifting Tag Protein (FAST). Appl Environ Microbiol 2019; 85:AEM.00622-19. [PMID: 31076434 DOI: 10.1128/aem.00622-19] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 05/07/2019] [Indexed: 01/03/2023] Open
Abstract
Visualizing protein localization and characterizing gene expression activity in live Clostridium cells is limited for lack of a real-time, highly fluorescent, oxygen-independent reporter system. Enzymatic reporter systems have been used successfully for many years with Clostridium spp.; however, these assays do not allow for real-time analysis of gene expression activity with flow cytometry or for visualizing protein localization through fusion proteins. Commonly used fluorescent reporter proteins require oxygen for chromophore maturation and cannot be used for most strictly anaerobic Clostridium organisms. Here we show that the fluorescence-activating and absorption-shifting tag protein (FAST), when associated with the fluorogenic ligand 4-hydroxy-3-methylbenzylidene-rhodanine (HMBR; now commercially available) and other commercially available ligands, is highly fluorescent in Clostridium acetobutylicum under anaerobic conditions. Using flow cytometry and a fluorescence microplate reader, we demonstrated FAST as a reporter system by employing the promoters of the C. acetobutylicum thiolase (thl), acetoacetate decarboxylase (adc), and phosphotransbutyrylase (ptb) metabolic genes, as well as a mutant Pthl and modified ribosome binding site (RBS) versions of Padc and Pptb Flow cytometry-based sorting was efficient and fast in sorting FAST-expressing cells, and positively and negatively sorted cells could be effectively recultured. FAST was also used to tag and examine protein localization of the predicted cell division FtsZ partner protein, ZapA, to visualize the divisome localization in live C. acetobutylicum cells. Our findings suggest that FAST can be used to further investigate Clostridium divisomes and more broadly the localization and expression levels of other proteins in Clostridium organisms, thus enabling cell biology studies with these organisms.IMPORTANCE FAST in association with the fluorogenic ligand HMBR is characterized as a successful, highly fluorescent reporter system in C. acetobutylicum FAST can be used to distinguish between promoters in live cells using flow cytometry or a fluorescence microplate reader and can be used to tag and examine protein localization in live, anaerobically grown cells. Given that FAST is highly fluorescent under anaerobic conditions, it can be used in several applications of this and likely many Clostridium organisms and other strict anaerobes, including studies involving cell sorting, sporulation dynamics, and population characterization in pure as well as mixed cultures, such as those in various native or synthetic microbiomes and syntrophic cultures.
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Wettmann L, Kruse K. The Min-protein oscillations in Escherichia coli: an example of self-organized cellular protein waves. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0111. [PMID: 29632263 DOI: 10.1098/rstb.2017.0111] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2017] [Indexed: 01/09/2023] Open
Abstract
In the rod-shaped bacterium Escherichia coli, selection of the cell centre as the division site involves pole-to-pole oscillations of the proteins MinC, MinD and MinE. This spatio-temporal pattern emerges from interactions among the Min proteins and with the cytoplasmic membrane. Combining experimental studies in vivo and in vitro together with theoretical analysis has led to a fairly good understanding of Min-protein self-organization. In different geometries, the system can, in addition to standing waves, also produce travelling planar and spiral waves as well as coexisting stable stationary distributions. Today it stands as one of the best-studied examples of cellular self-organization of proteins.This article is part of the theme issue 'Self-organization in cell biology'.
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Affiliation(s)
- Lukas Wettmann
- Theoretische Physik, Universität des Saarlandes, Postfach 151150, 66041 Saarbrücken, Germany
| | - Karsten Kruse
- Departments of Biochemistry and Theoretical Physics, NCCR Chemical Biology, University of Geneva, 1211 Geneva, Switzerland
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7
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Affiliation(s)
- Ashoka Chary Taviti
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
- Manipal Academy of Higher Education, Manipal, India
| | - Tushar Kant Beuria
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
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8
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Valenčíková R, Krascsenitsová E, Labajová N, Makroczyová J, Barák I. Clostridial DivIVA and MinD interact in the absence of MinJ. Anaerobe 2018; 50:22-31. [PMID: 29408597 DOI: 10.1016/j.anaerobe.2018.01.013] [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: 10/13/2017] [Revised: 01/04/2018] [Accepted: 01/29/2018] [Indexed: 11/25/2022]
Abstract
One of the key regulators ensuring proper Z-ring placement in rod-shaped bacteria is the Min system. It does so by creating a concentration gradient of the MinC septation inhibitor along the cell axis. In Escherichia coli, this gradient is established by a MinE-mediated pole-to-pole oscillation of the MinCDE complex. In Bacillus subtilis, the creation of an inhibitory gradient relies on the MinJ and DivIVA pair of topological determinants, which target MinCD to the newly formed cell poles. Introducing the E. coli oscillating Min system into B. subtilis leads to a sporulation defect, suggesting that oscillation is incompatible with sporulation. However, Clostridia, close endospore-forming relatives of Bacilli, do encode oscillating Min homologues in various combinations together with homologues from the less dynamic B. subtilis Min system. Here we address the questions of how these two systems could exist side-by-side and how they influence one another by studying the Clostridium beijerinckii and Clostridium difficile Min systems. The toolbox of genetic manipulations and fluorescent protein fusions in Clostridia is limited, therefore B. subtilis and E. coli were chosen as heterologous systems for studying these proteins. In B. subtilis, MinD and DivIVA interact through MinJ; here, however, we discovered that the MinD and DivIVA proteins of both C. difficile, and C. beijerinckii, interact directly, which is surprising in the latter case, since that organism also encodes a MinJ homologue. We confirm this interaction using both in vitro and in vivo methods. We also show that C. beijerinckii MinJ is probably not in direct contact with DivIVACb and, unlike B. subtilis MinJ, does not mediate the MinDCb and DivIVACb interaction. Our results suggest that the Clostridia Min system uses a new mechanism of function.
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Affiliation(s)
- Romana Valenčíková
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia
| | - Eva Krascsenitsová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia
| | - Naďa Labajová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia
| | - Jana Makroczyová
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia
| | - Imrich Barák
- Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 845 51 Bratislava, Slovakia.
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9
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Lorenzoni ASG, Dantas GC, Bergsma T, Ferreira H, Scheffers DJ. Xanthomonas citri MinC Oscillates from Pole to Pole to Ensure Proper Cell Division and Shape. Front Microbiol 2017; 8:1352. [PMID: 28769912 PMCID: PMC5515816 DOI: 10.3389/fmicb.2017.01352] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 07/04/2017] [Indexed: 01/08/2023] Open
Abstract
Xanthomonas citri (Xac) is the causal agent of citrus canker, a disease that affects citrus crops and causes economic impact worldwide. To further characterize cell division in this plant pathogen, we investigated the role of the protein MinC in cell division, chromosome segregation, and peptidoglycan incorporation by deleting the gene minC using allele exchange. Xac with minC deleted exhibited the classic Δmin phenotype observed in other bacteria deleted for min components: minicells and short filamentation. In addition we noticed the formation of branches, which is similar to what was previously described for Escherichia coli deleted for either min or for several low molecular weight penicillin-binding proteins (PBPs). The branching phenotype was medium dependent and probably linked to gluconeogenic growth. We complemented the minC gene by integrating gfp-minC into the amy locus. Xac complemented strains displayed a wild-type phenotype. In addition, GFP-MinC oscillated from pole to pole, similar to MinCD oscillations observed in E. coli and more recently in Synechococcus elongatus. Further investigation of the branching phenotype revealed that in branching cells nucleoid organization, divisome formation and peptidoglycan incorporation were disrupted.
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Affiliation(s)
- André S G Lorenzoni
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningen, Netherlands
| | - Giordanni C Dantas
- Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual PaulistaRio Claro, Brazil
| | - Tessa Bergsma
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningen, Netherlands
| | - Henrique Ferreira
- Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual PaulistaRio Claro, Brazil
| | - Dirk-Jan Scheffers
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningen, Netherlands
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Abstract
The last three decades have witnessed an explosion of discoveries about the mechanistic details of binary fission in model bacteria such as Escherichia coli, Bacillus subtilis, and Caulobacter crescentus. This was made possible not only by advances in microscopy that helped answer questions about cell biology but also by clever genetic manipulations that directly and easily tested specific hypotheses. More recently, research using understudied organisms, or nonmodel systems, has revealed several alternate mechanistic strategies that bacteria use to divide and propagate. In this review, we highlight new findings and compare these strategies to cell division mechanisms elucidated in model organisms.
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Affiliation(s)
- Prahathees J Eswara
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, Florida 33620;
| | - Kumaran S Ramamurthi
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-5132;
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Wu F, Halatek J, Reiter M, Kingma E, Frey E, Dekker C. Multistability and dynamic transitions of intracellular Min protein patterns. Mol Syst Biol 2016; 12:873. [PMID: 27279643 PMCID: PMC4923923 DOI: 10.15252/msb.20156724] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 05/13/2016] [Accepted: 05/14/2016] [Indexed: 11/09/2022] Open
Abstract
Cells owe their internal organization to self-organized protein patterns, which originate and adapt to growth and external stimuli via a process that is as complex as it is little understood. Here, we study the emergence, stability, and state transitions of multistable Min protein oscillation patterns in live Escherichia coli bacteria during growth up to defined large dimensions. De novo formation of patterns from homogenous starting conditions is observed and studied both experimentally and in simulations. A new theoretical approach is developed for probing pattern stability under perturbations. Quantitative experiments and simulations show that, once established, Min oscillations tolerate a large degree of intracellular heterogeneity, allowing distinctly different patterns to persist in different cells with the same geometry. Min patterns maintain their axes for hours in experiments, despite imperfections, expansion, and changes in cell shape during continuous cell growth. Transitions between multistable Min patterns are found to be rare events induced by strong intracellular perturbations. The instances of multistability studied here are the combined outcome of boundary growth and strongly nonlinear kinetics, which are characteristic of the reaction-diffusion patterns that pervade biology at many scales.
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Affiliation(s)
- Fabai Wu
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands
| | - Jacob Halatek
- Arnold-Sommerfeld-Center for Theoretical Physics and Center for NanoScience, Ludwig-Maximilians-Universität München, München, Germany
| | - Matthias Reiter
- Arnold-Sommerfeld-Center for Theoretical Physics and Center for NanoScience, Ludwig-Maximilians-Universität München, München, Germany
| | - Enzo Kingma
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands
| | - Erwin Frey
- Arnold-Sommerfeld-Center for Theoretical Physics and Center for NanoScience, Ludwig-Maximilians-Universität München, München, Germany
| | - Cees Dekker
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands
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Makroczyová J, Jamroškovič J, Krascsenitsová E, Labajová N, Barák I. Oscillating behavior of Clostridium difficile Min proteins in Bacillus subtilis. Microbiologyopen 2016; 5:387-401. [PMID: 26817670 PMCID: PMC4905992 DOI: 10.1002/mbo3.337] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 12/20/2015] [Accepted: 12/30/2015] [Indexed: 01/07/2023] Open
Abstract
In rod‐shaped bacteria, the proper placement of the division septum at the midcell relies, at least partially, on the proteins of the Min system as an inhibitor of cell division. The main principle of Min system function involves the formation of an inhibitor gradient along the cell axis; however, the establishment of this gradient differs between two well‐studied gram‐negative and gram‐positive bacteria. While in gram‐negative Escherichia coli, the Min system undergoes pole‐to‐pole oscillation, in gram‐positive Bacillus subtilis, proper spatial inhibition is achieved by the preferential attraction of the Min proteins to the cell poles. Nevertheless, when E.coli Min proteins are inserted into B.subtilis cells, they still oscillate, which negatively affects asymmetric septation during sporulation in this organism. Interestingly, homologs of both Min systems were found to be present in various combinations in the genomes of anaerobic and endospore‐forming Clostridia, including the pathogenic Clostridium difficile. Here, we have investigated the localization and behavior of C.difficile Min protein homologs and showed that MinDE proteins of C.difficile can oscillate when expressed together in B.subtilis cells. We have also investigated the effects of this oscillation on B.subtilis sporulation, and observed decreased sporulation efficiency in strains harboring the MinDE genes. Additionally, we have evaluated the effects of C.difficile Min protein expression on vegetative division in this heterologous host.
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Affiliation(s)
- Jana Makroczyová
- Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Ján Jamroškovič
- Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Eva Krascsenitsová
- Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Nad'a Labajová
- Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Imrich Barák
- Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
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