1
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Morrison JJ, Camberg JL. Building the Bacterial Divisome at the Septum. Subcell Biochem 2024; 104:49-71. [PMID: 38963483 DOI: 10.1007/978-3-031-58843-3_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
Across living organisms, division is necessary for cell survival and passing heritable information to the next generation. For this reason, cell division is highly conserved among eukaryotes and prokaryotes. Among the most highly conserved cell division proteins in eukaryotes are tubulin and actin. Tubulin polymerizes to form microtubules, which assemble into cytoskeletal structures in eukaryotes, such as the mitotic spindle that pulls chromatids apart during mitosis. Actin polymerizes to form a morphological framework for the eukaryotic cell, or cytoskeleton, that undergoes reorganization during mitosis. In prokaryotes, two of the most highly conserved cell division proteins are the tubulin homolog FtsZ and the actin homolog FtsA. In this chapter, the functions of the essential bacterial cell division proteins FtsZ and FtsA and their roles in assembly of the divisome at the septum, the site of cell division, will be discussed. In most bacteria, including Escherichia coli, the tubulin homolog FtsZ polymerizes at midcell, and this step is crucial for recruitment of many other proteins to the division site. For this reason, both FtsZ abundance and polymerization are tightly regulated by a variety of proteins. The actin-like FtsA protein polymerizes and tethers FtsZ polymers to the cytoplasmic membrane. Additionally, FtsA interacts with later stage cell division proteins, which are essential for division and for building the new cell wall at the septum. Recent studies have investigated how actin-like polymerization of FtsA on the lipid membrane may impact division, and we will discuss this and other ways that division in bacteria is regulated through FtsZ and FtsA.
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Affiliation(s)
- Josiah J Morrison
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, RI, USA
| | - Jodi L Camberg
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, RI, USA.
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2
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Porter KJ, Cao L, Chen Y, TerBush AD, Chen C, Erickson HP, Osteryoung KW. The Arabidopsis thaliana chloroplast division protein FtsZ1 counterbalances FtsZ2 filament stability in vitro. J Biol Chem 2021; 296:100627. [PMID: 33812992 PMCID: PMC8142252 DOI: 10.1016/j.jbc.2021.100627] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 11/18/2022] Open
Abstract
Bacterial cell and chloroplast division are driven by a contractile “Z ring” composed of the tubulin-like cytoskeletal GTPase FtsZ. Unlike bacterial Z rings, which consist of a single FtsZ, the chloroplast Z ring in plants is composed of two FtsZ proteins, FtsZ1 and FtsZ2. Both are required for chloroplast division in vivo, but their biochemical relationship is poorly understood. We used GTPase assays, light scattering, transmission electron microscopy, and sedimentation assays to investigate the assembly behavior of purified Arabidopsis thaliana (At) FtsZ1 and AtFtsZ2 both individually and together. Both proteins exhibited GTPase activity. AtFtsZ2 assembled relatively quickly, forming protofilament bundles that were exceptionally stable, as indicated by their sustained assembly and slow disassembly. AtFtsZ1 did not form detectable protofilaments on its own. When mixed with AtFtsZ2, AtFtsZ1 reduced the extent and rate of AtFtsZ2 assembly, consistent with its previously demonstrated ability to promote protofilament subunit turnover in living cells. Mixing the two FtsZ proteins did not increase the overall GTPase activity, indicating that the effect of AtFtsZ1 on AtFtsZ2 assembly was not due to a stimulation of GTPase activity. However, the GTPase activity of AtFtsZ1 was required to reduce AtFtsZ2 assembly. Truncated forms of AtFtsZ1 and AtFtsZ2 consisting of only their conserved core regions largely recapitulated the behaviors of the full-length proteins. Our in vitro findings provide evidence that FtsZ1 counterbalances the stability of FtsZ2 filaments in the regulation of chloroplast Z-ring dynamics and suggest that restraining FtsZ2 self-assembly is a critical function of FtsZ1 in chloroplasts.
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Affiliation(s)
- Katie J Porter
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
| | - Lingyan Cao
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
| | - Yaodong Chen
- Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Allan D TerBush
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
| | - Cheng Chen
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
| | - Harold P Erickson
- Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina, USA
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3
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Multi-functional regulator MapZ controls both positioning and timing of FtsZ polymerization. Biochem J 2019; 476:1433-1444. [PMID: 31036719 DOI: 10.1042/bcj20190138] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/25/2019] [Accepted: 04/26/2019] [Indexed: 12/11/2022]
Abstract
The tubulin-like GTPase protein FtsZ, which forms a discontinuous cytokinetic ring at mid-cell, is a central player to recruit the division machinery to orchestrate cell division. To guarantee the production of two identical daughter cells, the assembly of FtsZ, namely Z-ring, and its precise positioning should be finely regulated. In Streptococcus pneumoniae, the positioning of Z-ring at the division site is mediated by a bitopic membrane protein MapZ (mid-cell-anchored protein Z) through direct interactions between the intracellular domain (termed MapZ-N (the intracellular domain of MapZ)) and FtsZ. Using nuclear magnetic resonance titration experiments, we clearly assigned the key residues involved in the interactions. In the presence of MapZ-N, FtsZ gains a shortened activation delay, a lower critical concentration for polymerization and a higher cooperativity towards GTP hydrolysis. On the other hand, MapZ-N antagonizes the lateral interactions of single-stranded filaments of FtsZ, thus slows down the formation of highly bundled FtsZ polymers and eventually maintains FtsZ at a dynamic state. Altogether, we conclude that MapZ is not only an accelerator to trigger the polymerization of FtsZ, but also a brake to tune the velocity to form the end-product, FtsZ bundles. These findings suggest that MapZ is a multi-functional regulator towards FtsZ that controls both the precise positioning and proper timing of FtsZ polymerization.
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4
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Kopacz MM, Lorenzoni ASG, Polaquini CR, Regasini LO, Scheffers D. Purification and characterization of FtsZ from the citrus canker pathogen Xanthomonas citri subsp. citri. Microbiologyopen 2019; 8:e00706. [PMID: 30085414 PMCID: PMC6528577 DOI: 10.1002/mbo3.706] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 07/06/2018] [Accepted: 07/06/2018] [Indexed: 12/04/2022] Open
Abstract
Xanthomonas citri subsp. citri (Xac) is the causative agent of citrus canker, a plant disease that significantly impacts citriculture. In earlier work, we showed that alkylated derivatives of gallic acid have antibacterial action against Xac and target both the cell division protein FtsZ and membrane integrity in Bacillus subtilis. Here, we have purified native XacFtsZ and characterized its GTP hydrolysis and polymerization properties. In a surprising manner, inhibition of XacFtsZ activity by alkyl gallates is not as strong as observed earlier with B. subtilis FtsZ. As the alkyl gallates efficiently permeabilize Xac membranes, we propose that this is the primary mode of antibacterial action of these compounds.
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Affiliation(s)
- Malgorzata M. Kopacz
- Department of Molecular MicrobiologyGroningen Biomolecular Sciences and Biotechnology InstituteUniversity of GroningenGroningenThe Netherlands
- Present address:
Department of Chemical EngineeringBiotechnology and Environmental TechnologyUniversity of Southern DenmarkOdense MDenmark
| | - André S. G. Lorenzoni
- Department of Molecular MicrobiologyGroningen Biomolecular Sciences and Biotechnology InstituteUniversity of GroningenGroningenThe Netherlands
| | - Carlos R. Polaquini
- Laboratory of Antibiotics and ChemotherapeuticsDepartment of Chemistry and Environmental SciencesInstitute of Biosciences, Humanities and Exact SciencesSão Paulo State University (UNESP)São José do Rio PretoSPBrazil
| | - Luis O. Regasini
- Laboratory of Antibiotics and ChemotherapeuticsDepartment of Chemistry and Environmental SciencesInstitute of Biosciences, Humanities and Exact SciencesSão Paulo State University (UNESP)São José do Rio PretoSPBrazil
| | - Dirk‐Jan Scheffers
- Department of Molecular MicrobiologyGroningen Biomolecular Sciences and Biotechnology InstituteUniversity of GroningenGroningenThe Netherlands
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5
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Wemyss AM, Chmel NP, Lobo DP, Sutherland JA, Dafforn TR, Rodger A. Fluorescence detected linear dichroism spectroscopy: A selective and sensitive probe for fluorophores in flow-oriented systems. Chirality 2018; 30:227-237. [PMID: 29314266 DOI: 10.1002/chir.22795] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 10/22/2017] [Accepted: 10/27/2017] [Indexed: 11/06/2022]
Abstract
Fluorescence detection typically enhances sensitivity and selectivity for fluorescent analytes. The potential for combining fluorescence detection with flow orientation of the sample in the normal configuration of linear dichroism experiments is explored in this work by measuring the fluorescence emitted from flow-orientated DNA-bound ligands and M13 bacteriophage. Data for ethidium bromide, Hoechst 33258, and 4,6-diamidino-2-phenyindole are presented. The theoretical basis of the technique is also presented for instruments running in both the fixed direct-current mode, which is the normal operation mode of circular dichroism spectropolarimeters, and also in fixed high-tension voltage mode. The role of the stray light reaching the detector that results in a spectral shape in fixed direct current mode that resembles the shape of a linear dichroism spectrum, rather than the expected reduced linear dichroism, is also explored.
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Affiliation(s)
- Alan M Wemyss
- Department of Chemistry and MOAC Doctoral Training Centre, University of Warwick, Coventry, UK
| | - Nikola P Chmel
- Department of Chemistry and MOAC Doctoral Training Centre, University of Warwick, Coventry, UK
| | - Daniela P Lobo
- Department of Chemistry and MOAC Doctoral Training Centre, University of Warwick, Coventry, UK
| | - John A Sutherland
- Department of Chemistry and Physics, Augusta University, Augusta, Georgia, USA
| | | | - Alison Rodger
- Department of Chemistry and MOAC Doctoral Training Centre, University of Warwick, Coventry, UK.,Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
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6
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Lariviere PJ, Szwedziak P, Mahone CR, Löwe J, Goley ED. FzlA, an essential regulator of FtsZ filament curvature, controls constriction rate during Caulobacter division. Mol Microbiol 2018; 107:180-197. [PMID: 29119622 PMCID: PMC5760450 DOI: 10.1111/mmi.13876] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 10/13/2017] [Accepted: 11/07/2017] [Indexed: 12/24/2022]
Abstract
During bacterial division, polymers of the tubulin-like GTPase FtsZ assemble at midcell to form the cytokinetic Z-ring, which coordinates peptidoglycan (PG) remodeling and envelope constriction. Curvature of FtsZ filaments promotes membrane deformation in vitro, but its role in division in vivo remains undefined. Inside cells, FtsZ directs PG insertion at the division plane, though it is unclear how FtsZ structure and dynamics are mechanistically coupled to PG metabolism. Here we study FzlA, a division protein that stabilizes highly curved FtsZ filaments, as a tool for assessing the contribution of FtsZ filament curvature to constriction. We show that in Caulobacter crescentus, FzlA must bind to FtsZ for division to occur and that FzlA-mediated FtsZ curvature is correlated with efficient division. We observed that FzlA influences constriction rate, and that this activity is associated with its ability to bind and curve FtsZ polymers. Further, we found that a slowly constricting fzlA mutant strain develops 'pointy' poles, suggesting that FzlA influences the relative contributions of radial versus longitudinal PG insertion at the septum. These findings implicate FzlA as a critical coordinator of envelope constriction through its interaction with FtsZ and suggest a functional link between FtsZ curvature and efficient constriction in C. crescentus.
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Affiliation(s)
- Patrick J. Lariviere
- Department of Biological ChemistryJohns Hopkins University School of MedicineBaltimoreMD21205USA
| | - Piotr Szwedziak
- Structural Studies DivisionMRC Laboratory of Molecular BiologyCambridgeCB20QHUK
- Present address:
Institute of Molecular Biology and BiophysicsETH Zürich8093 ZürichSwitzerland
| | - Christopher R. Mahone
- Department of Biological ChemistryJohns Hopkins University School of MedicineBaltimoreMD21205USA
| | - Jan Löwe
- Structural Studies DivisionMRC Laboratory of Molecular BiologyCambridgeCB20QHUK
| | - Erin D. Goley
- Department of Biological ChemistryJohns Hopkins University School of MedicineBaltimoreMD21205USA
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7
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Characterization of the in vitro assembly of FtsZ in Arthrobacter strain A3 using light scattering. Int J Biol Macromol 2016; 91:294-8. [PMID: 27164494 DOI: 10.1016/j.ijbiomac.2016.04.090] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 04/27/2016] [Accepted: 04/28/2016] [Indexed: 12/16/2022]
Abstract
The self-assembly of FtsZ, the bacterial homolog of tubulin, plays an essential role in cell division. Light scattering technique is applied to real-time monitor the in vitro assembly of FtsZ in Arthrobacter strain A3, a newly isolated psychrotrophic bacterium. The critical concentration needed for the assembly is estimated as 6.7μM. The polymerization of FtsZ in Arthrobacter strain A3 requires both GTP and divalent metal ions, while salt is an unfavorable condition for the assembly. The FtsZ polymerizes under a wide range of pHs, with the fastest rate around pH 6.0. The FtsZ from Arthrobacter strain A3 resembles Mycobacterium tuberculosis FtsZ in terms of the dependence on divalent metal ions and the slow polymerization rate, while it is different from M. tuberculosis FtsZ considering the sensitivity to salt and pH. The comparison of FtsZ from different organisms will greatly advance our understanding of the biological role of the key cell division protein.
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8
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Duggirala S, Nankar RP, Rajendran S, Doble M. Phytochemicals as Inhibitors of Bacterial Cell Division Protein FtsZ: Coumarins Are Promising Candidates. Appl Biochem Biotechnol 2014; 174:283-96. [DOI: 10.1007/s12010-014-1056-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 07/09/2014] [Indexed: 10/25/2022]
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9
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Król E, Scheffers DJ. FtsZ polymerization assays: simple protocols and considerations. J Vis Exp 2013:e50844. [PMID: 24300445 PMCID: PMC3991336 DOI: 10.3791/50844] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
During bacterial cell division, the essential protein FtsZ assembles in the middle of the cell to form the so-called Z-ring. FtsZ polymerizes into long filaments in the presence of GTP in vitro, and polymerization is regulated by several accessory proteins. FtsZ polymerization has been extensively studied in vitro using basic methods including light scattering, sedimentation, GTP hydrolysis assays and electron microscopy. Buffer conditions influence both the polymerization properties of FtsZ, and the ability of FtsZ to interact with regulatory proteins. Here, we describe protocols for FtsZ polymerization studies and validate conditions and controls using Escherichia coli and Bacillus subtilis FtsZ as model proteins. A low speed sedimentation assay is introduced that allows the study of the interaction of FtsZ with proteins that bundle or tubulate FtsZ polymers. An improved GTPase assay protocol is described that allows testing of GTP hydrolysis over time using various conditions in a 96-well plate setup, with standardized incubation times that abolish variation in color development in the phosphate detection reaction. The preparation of samples for light scattering studies and electron microscopy is described. Several buffers are used to establish suitable buffer pH and salt concentration for FtsZ polymerization studies. A high concentration of KCl is the best for most of the experiments. Our methods provide a starting point for the in vitro characterization of FtsZ, not only from E. coli and B. subtilis but from any other bacterium. As such, the methods can be used for studies of the interaction of FtsZ with regulatory proteins or the testing of antibacterial drugs which may affect FtsZ polymerization.
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Affiliation(s)
- Ewa Król
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen
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10
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Natale P, Pazos M, Vicente M. TheEscherichia colidivisome: born to divide. Environ Microbiol 2013; 15:3169-82. [DOI: 10.1111/1462-2920.12227] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 07/18/2013] [Accepted: 07/23/2013] [Indexed: 11/27/2022]
Affiliation(s)
- Paolo Natale
- Centro Nacional de Biotecnología (CNB-CSIC); C/Darwin n° 3 E-28049 Madrid Spain
| | - Manuel Pazos
- Centro Nacional de Biotecnología (CNB-CSIC); C/Darwin n° 3 E-28049 Madrid Spain
| | - Miguel Vicente
- Centro Nacional de Biotecnología (CNB-CSIC); C/Darwin n° 3 E-28049 Madrid Spain
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11
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Ahijado-Guzmán R, Alfonso C, Reija B, Salvarelli E, Mingorance J, Zorrilla S, Monterroso B, Rivas G. Control by potassium of the size distribution of Escherichia coli FtsZ polymers is independent of GTPase activity. J Biol Chem 2013; 288:27358-27365. [PMID: 23940054 DOI: 10.1074/jbc.m113.482943] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The influence of potassium content (at neutral pH and millimolar Mg(2+)) on the size distribution of FtsZ polymers formed in the presence of constantly replenished GTP under steady-state conditions was studied by a combination of biophysical methods. The size of the GTP-FtsZ polymers decreased with lower potassium concentration, in contrast with the increase in the mass of the GDP-FtsZ oligomers, whereas no effect was observed on FtsZ GTPase activity and critical concentration of polymerization. Remarkably, the concerted formation of a narrow size distribution of GTP-FtsZ polymers previously observed at high salt concentration was maintained in all KCl concentrations tested. Polymers induced with guanosine 5'-(α,β-methylene)triphosphate, a slowly hydrolyzable analog of GTP, became larger and polydisperse as the potassium concentration was decreased. Our results suggest that the potassium dependence of the GTP-FtsZ polymer size may be related to changes in the subunit turnover rate that are independent of the GTP hydrolysis rate. The formation of a narrow size distribution of FtsZ polymers under very different solution conditions indicates that it is an inherent feature of FtsZ, not observed in other filament-forming proteins, with potential implications in the structural organization of the functional Z-ring.
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Affiliation(s)
- Rubén Ahijado-Guzmán
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), 28040 Madrid
| | - Carlos Alfonso
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), 28040 Madrid
| | - Belén Reija
- Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid
| | - Estefanía Salvarelli
- Servicio de Microbiología, Hospital Universitario La Paz, IdiPAZ, 28046 Madrid; Biomol Informatics SL, Cantoblanco, 28049 Madrid, Spain
| | - Jesús Mingorance
- Servicio de Microbiología, Hospital Universitario La Paz, IdiPAZ, 28046 Madrid
| | | | - Begoña Monterroso
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), 28040 Madrid.
| | - Germán Rivas
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), 28040 Madrid.
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12
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Buske PJ, Levin PA. A flexible C-terminal linker is required for proper FtsZ assembly in vitro and cytokinetic ring formation in vivo. Mol Microbiol 2013; 89:249-63. [PMID: 23692518 DOI: 10.1111/mmi.12272] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2013] [Indexed: 02/01/2023]
Abstract
Assembly of the cytoskeletal protein FtsZ into a ring-like structure is required for bacterial cell division. Structurally, FtsZ consists of four domains: the globular N-terminal core, a flexible linker, 8-9 conserved residues implicated in interactions with modulatory proteins, and a highly variable set of 4-10 residues at its very C terminus. Largely ignored and distinguished by lack of primary sequence conservation, the linker is presumed to be intrinsically disordered. Here we employ genetics, biochemistry and cytology to dissect the role of the linker in FtsZ function. Data from chimeric FtsZs substituting the native linker with sequences from unrelated FtsZs as well as a helical sequence from human beta-catenin indicate that while variations in the primary sequence are well tolerated, an intrinsically disordered linker is essential for Bacillus subtilis FtsZ assembly. Linker lengths ranging from 25 to 100 residues supported FtsZ assembly, but replacing the B. subtilis FtsZ linker with a 249-residue linker from Agrobacterium tumefaciens FtsZ interfered with cell division. Overall, our results support a model in which the linker acts as a flexible tether allowing FtsZ to associate with the membrane through a conserved C-terminal domain while simultaneously interacting with itself and modulatory proteins in the cytoplasm.
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Affiliation(s)
- P J Buske
- Department of Biology, Washington University in St Louis, St Louis, MO 63130, USA
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13
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Abstract
Prokaryotic cell division is a highly orchestrated process requiring the formation of a wide range of biomolecular complexes, perhaps the most important of these involving the prokaryotic tubulin homologue FtsZ, a fibre-forming GTPase. FtsZ assembles into a ring (the Z-ring) on the inner surface of the inner membrane at the site of cell division. The Z-ring then acts as a recruitment site for at least ten other proteins which form the division apparatus. One of these proteins, ZapA, acts to enhance lateral associations between FtsZ fibres to form bundles. Previously we have expressed, purified and crystallized ZapA and demonstrated that it exists as a tetramer. We also showed that ZapA binds to FtsZ polymers, strongly promoting their bundling, while inhibiting FtsZ GTPase activity by inducing conformational changes in the bound nucleotide. In the present study we investigate the importance of the tetramerization of ZapA on its function. We generated a number of mutant forms of ZapA with the aim of disrupting the dimer-dimer interface. We show that one of these mutants, I83E, is fully folded and binds to FtsZ, but is a constitutive dimer. Using this mutant we show that tetramerization is a requirement for both FtsZ bundling and GTPase modulation activities.
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14
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Hicks MR, Rodger A, Lin YP, Jones NC, Hoffmann SV, Dafforn TR. Rapid Injection Linear Dichroism for Studying the Kinetics of Biological Processes. Anal Chem 2012; 84:6561-6. [DOI: 10.1021/ac300842h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Matthew R. Hicks
- Department of Chemistry and
Warwick Centre for Analytical Science, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Alison Rodger
- Department of Chemistry and
Warwick Centre for Analytical Science, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Yu-pin Lin
- School of Biosciences, University of Birmingham, Birmingham, B15 2TT, United
Kingdom
| | - Nykola C. Jones
- Institute for Storage
Ring Facilities
(ISA), Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Søren Vrønning Hoffmann
- Institute for Storage
Ring Facilities
(ISA), Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Timothy R. Dafforn
- School of Biosciences, University of Birmingham, Birmingham, B15 2TT, United
Kingdom
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15
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Identification of ZapD as a cell division factor that promotes the assembly of FtsZ in Escherichia coli. J Bacteriol 2012; 194:3189-98. [PMID: 22505682 DOI: 10.1128/jb.00176-12] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The tubulin homolog FtsZ forms a polymeric membrane-associated ring structure (Z ring) at midcell that establishes the site of division and provides an essential framework for the localization of a multiprotein molecular machine that promotes division in Escherichia coli. A number of regulatory proteins interact with FtsZ and modulate FtsZ assembly/disassembly processes, ensuring the spatiotemporal integrity of cytokinesis. The Z-associated proteins (ZapA, ZapB, and ZapC) belong to a group of FtsZ-regulatory proteins that exhibit functionally redundant roles in stabilizing FtsZ-ring assembly by binding and bundling polymeric FtsZ at midcell. In this study, we report the identification of ZapD (YacF) as a member of the E. coli midcell division machinery. Genetics and cell biological evidence indicate that ZapD requires FtsZ but not other downstream division proteins for localizing to midcell, where it promotes FtsZ-ring assembly via molecular mechanisms that overlap with ZapA. Biochemical evidence indicates that ZapD directly interacts with FtsZ and promotes bundling of FtsZ protofilaments. Similarly to ZapA, ZapB, and ZapC, ZapD is dispensable for division and therefore belongs to the growing group of FtsZ-associated proteins in E. coli that aid in the overall fitness of the division process.
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16
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The mechanics of FtsZ fibers. Biophys J 2012; 102:731-8. [PMID: 22385843 DOI: 10.1016/j.bpj.2012.01.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 12/02/2011] [Accepted: 01/11/2012] [Indexed: 10/28/2022] Open
Abstract
Inhibition of the Fts family of proteins causes the growth of long filamentous cells, indicating that they play some role in cell division. FtsZ polymerizes into protofilaments and assembles into the Z-ring at the future site of the septum of cell division. We analyze the rigidity of GTP-bound FtsZ protofilaments by using cryoelectron microscopy to sample their bending fluctuations. We find that the FtsZ-GTP filament rigidity is κ=4.7±1.0×10(-27) Nm(2), with a corresponding thermal persistence length of l(p)=1.15±0.25μm, much higher than previous estimates. In conjunction with other model studies, our new higher estimate for FtsZ rigidity suggests that contraction of the Z-ring may generate sufficient force to facilitate cell division. The good agreement between the measured mode amplitudes and that predicted by equipartition of energy supports our use of a simple mechanical model for FtsZ fibers. The study also provides evidence that the fibers have no intrinsic global or local curvatures, such as might be caused by partial hydrolysis of the GTP.
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17
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Schaffner-Barbero C, Martín-Fontecha M, Chacón P, Andreu JM. Targeting the assembly of bacterial cell division protein FtsZ with small molecules. ACS Chem Biol 2012; 7:269-77. [PMID: 22047077 DOI: 10.1021/cb2003626] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
FtsZ is the key protein of bacterial cell division and an emergent target for new antibiotics. It is a filament-forming GTPase and a structural homologue of eukaryotic tubulin. A number of FtsZ-interacting compounds have been reported, some of which have powerful antibacterial activity. Here we review recent advances and new approaches in modulating FtsZ assembly with small molecules. This includes analyzing their chemical features, binding sites, mechanisms of action, the methods employed, and computational insights, aimed at a better understanding of their molecular recognition by FtsZ and at rational antibiotic design.
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Affiliation(s)
- Claudia Schaffner-Barbero
- Tubulins and
FtsZ, Centro de
Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Mar Martín-Fontecha
- Medicinal Chemistry, Dept. Química
Orgánica I, Facultad de Ciencias Químicas, UCM, Avda. Complutense s/n, 28040 Madrid, Spain
| | - Pablo Chacón
- Structural Bioinformatics, Instituto
de Química Física Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - José M. Andreu
- Tubulins and
FtsZ, Centro de
Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
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Buske PJ, Levin PA. Extreme C terminus of bacterial cytoskeletal protein FtsZ plays fundamental role in assembly independent of modulatory proteins. J Biol Chem 2012; 287:10945-57. [PMID: 22298780 DOI: 10.1074/jbc.m111.330324] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Bacterial cell division typically requires assembly of the cytoskeletal protein FtsZ into a ring (Z-ring) at the nascent division site that serves as a foundation for assembly of the division apparatus. High resolution imaging suggests that the Z-ring consists of short, single-stranded polymers held together by lateral interactions. Several proteins implicated in stabilizing the Z-ring enhance lateral interactions between FtsZ polymers in vitro. Here we report that residues at the C terminus of Bacillus subtilis FtsZ (C-terminal variable region (CTV)) are both necessary and sufficient for stimulating lateral interactions in vitro in the absence of modulatory proteins. Swapping the 6-residue CTV from B. subtilis FtsZ with the 4-residue CTV from Escherichia coli FtsZ completely abolished lateral interactions between chimeric B. subtilis FtsZ polymers. The E. coli FtsZ chimera readily formed higher order structures normally seen only in the presence of molecular crowding agents. CTV-mediated lateral interactions are important for the integrity of the Z-ring because B. subtilis cells expressing the B. subtilis FtsZ chimera had a low frequency of FtsZ ring formation and a high degree of filamentation relative to wild-type cells. Site-directed mutagenesis of the B. subtilis CTV suggests that electrostatic forces are an important determinant of lateral interaction potential.
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Affiliation(s)
- Paul J Buske
- Department of Biology, Washington University, Saint Louis, Missouri 63130, USA
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