1
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Machado LESF, Castellen P, Blasios V, Ribeiro-Filho HV, Bisson-Filho AW, Benites Pariente JS, Nogueira MLC, Sforça M, Honorato RV, Lopes-de-Oliveira PS, Salinas RK, Andreu JM, Zeri AC, Gueiros-Filho FJ. NMR study of the interaction between MinC and FtsZ and modeling of the FtsZ:MinC complex. J Biol Chem 2025; 301:108169. [PMID: 39793890 PMCID: PMC11938149 DOI: 10.1016/j.jbc.2025.108169] [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: 06/06/2024] [Revised: 12/26/2024] [Accepted: 01/03/2025] [Indexed: 01/13/2025] Open
Abstract
The Min system is a key spatial regulator of cell division in rod-shaped bacteria and the first FtsZ-negative modulator to be recognized. Nevertheless, despite extensive genetic and in vitro studies, the molecular mechanism used by MinC to inhibit Z-ring formation remains incompletely understood. The crystallization of FtsZ in complex with other negative regulators such as SulA and MciZ has provided important structural information to corroborate in vitro experiments and establish the mechanism of Z-ring antagonism by these modulators. However, MinC and FtsZ have so far eluded co-crystallization, probably because their complex is too unstable to be crystallized. To gain structural insight into the mechanism of action of MinC, we determined the solution structure of the N-terminal domain of Bacillus subtilis MinC, and through NMR titration experiments and mutagenesis identified the binding interfaces involved in the MinCN-FtsZ interaction. By using our experimental results as restraints in docking, we also constructed a molecular model for the FtsZ:MinCN complex and validated it by molecular dynamics. The model shows that MinCN binding overlaps with the FtsZ polymerization interface on the C-terminal globular subdomain of FtsZ and, thus, provides a structural basis for MinCN inhibition of FtsZ filament formation. Given that the C-terminal polymerization interface of FtsZ corresponds to the plus end of FtsZ filaments, we propose that capping is the main mechanism employed by MinC to antagonize FtsZ polymerization.
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Affiliation(s)
| | - Patricia Castellen
- Departamento de Bioquímica, IQ, Universidade de São Paulo, São Paulo, Brazil; Brazilian Biosciences National Laboratory, LNBio, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, Brazil
| | - Valdir Blasios
- Departamento de Bioquímica, IQ, Universidade de São Paulo, São Paulo, Brazil
| | - Helder V Ribeiro-Filho
- Brazilian Biosciences National Laboratory, LNBio, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, Brazil
| | | | | | - Maria L C Nogueira
- Brazilian Biosciences National Laboratory, LNBio, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, Brazil
| | - Mauricio Sforça
- Brazilian Biosciences National Laboratory, LNBio, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, Brazil
| | - Rodrigo V Honorato
- Brazilian Biosciences National Laboratory, LNBio, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, Brazil
| | - Paulo S Lopes-de-Oliveira
- Brazilian Biosciences National Laboratory, LNBio, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, Brazil
| | - Roberto K Salinas
- Departamento de Bioquímica, IQ, Universidade de São Paulo, São Paulo, Brazil
| | - José M Andreu
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Ana C Zeri
- Brazilian Biosciences National Laboratory, LNBio, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, Brazil
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2
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Subcellular Dynamics of a Conserved Bacterial Polar Scaffold Protein. Genes (Basel) 2022; 13:genes13020278. [PMID: 35205323 PMCID: PMC8872289 DOI: 10.3390/genes13020278] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 02/05/2023] Open
Abstract
In order to survive, bacterial cells rely on precise spatiotemporal organization and coordination of essential processes such as cell growth, chromosome segregation, and cell division. Given the general lack of organelles, most bacteria are forced to depend on alternative localization mechanisms, such as, for example, geometrical cues. DivIVA proteins are widely distributed in mainly Gram-positive bacteria and were shown to bind the membrane, typically in regions of strong negative curvature, such as the cell poles and division septa. Here, they have been shown to be involved in a multitude of processes: from apical cell growth and chromosome segregation in actinobacteria to sporulation and inhibition of division re-initiation in firmicutes. Structural analyses revealed that DivIVA proteins can form oligomeric assemblies that constitute a scaffold for recruitment of other proteins. However, it remained unclear whether interaction with partner proteins influences DivIVA dynamics. Using structured illumination microscopy (SIM), single-particle tracking (SPT) microscopy, and fluorescent recovery after photobleaching (FRAP) experiments, we show that DivIVA from Corynebacterium glutamicum is mobilized by its binding partner ParB. In contrast, we show that the interaction between Bacillus subtilis DivIVA and its partner protein MinJ reduces DivIVA mobility. Furthermore, we show that the loss of the rod-shape leads to an increase in DivIVA dynamics in both organisms. Taken together, our study reveals the modulation of the polar scaffold protein by protein interactors and cell morphology. We reason that this leads to a very simple, yet robust way for actinobacteria to maintain polar growth and their rod-shape. In B. subtilis, however, the DivIVA protein is tailored towards a more dynamic function that allows quick relocalization from poles to septa upon division.
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3
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Messelink JJB, Meyer F, Bramkamp M, Broedersz CP. Single-cell growth inference of Corynebacterium glutamicum reveals asymptotically linear growth. eLife 2021; 10:e70106. [PMID: 34605403 PMCID: PMC8594916 DOI: 10.7554/elife.70106] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 10/01/2021] [Indexed: 11/13/2022] Open
Abstract
Regulation of growth and cell size is crucial for the optimization of bacterial cellular function. So far, single bacterial cells have been found to grow predominantly exponentially, which implies the need for tight regulation to maintain cell size homeostasis. Here, we characterize the growth behavior of the apically growing bacterium Corynebacterium glutamicum using a novel broadly applicable inference method for single-cell growth dynamics. Using this approach, we find that C. glutamicum exhibits asymptotically linear single-cell growth. To explain this growth mode, we model elongation as being rate-limited by the apical growth mechanism. Our model accurately reproduces the inferred cell growth dynamics and is validated with elongation measurements on a transglycosylase deficient ΔrodA mutant. Finally, with simulations we show that the distribution of cell lengths is narrower for linear than exponential growth, suggesting that this asymptotically linear growth mode can act as a substitute for tight division length and division symmetry regulation.
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Affiliation(s)
- Joris JB Messelink
- Arnold-Sommerfeld-Center for Theoretical Physics, Ludwig-Maximilians-Universität MünchenMunichGermany
| | - Fabian Meyer
- Ludwig-Maximilians-Universität München, Fakultät BiologiePlanegg-MartinsriedGermany
- Christian-Albrechts-Universität zu Kiel, Institut für allgemeine MikrobiologieKielGermany
| | - Marc Bramkamp
- Ludwig-Maximilians-Universität München, Fakultät BiologiePlanegg-MartinsriedGermany
- Christian-Albrechts-Universität zu Kiel, Institut für allgemeine MikrobiologieKielGermany
| | - Chase P Broedersz
- Arnold-Sommerfeld-Center for Theoretical Physics, Ludwig-Maximilians-Universität MünchenMunichGermany
- Department of Physics and Astronomy, Vrije Universiteit AmsterdamAmsterdamNetherlands
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4
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Springstein BL, Weissenbach J, Koch R, Stücker F, Stucken K. The role of the cytoskeletal proteins MreB and FtsZ in multicellular cyanobacteria. FEBS Open Bio 2020; 10:2510-2531. [PMID: 33112491 PMCID: PMC7714070 DOI: 10.1002/2211-5463.13016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 10/17/2020] [Accepted: 10/26/2020] [Indexed: 01/28/2023] Open
Abstract
Multiseriate and true‐branching cyanobacteria are at the peak of prokaryotic morphological complexity. However, little is known about the mechanisms governing multiplanar cell division and morphogenesis. Here, we study the function of the prokaryotic cytoskeletal proteins, MreB and FtsZ in Fischerella muscicola PCC 7414 and Chlorogloeopsis fritschii PCC 6912. Vancomycin and HADA labeling revealed a mixed apical, septal, and lateral trichome growth mode in F. muscicola, whereas C. fritschii exhibits septal growth. In all morphotypes from both species, MreB forms either linear filaments or filamentous strings and can interact with FtsZ. Furthermore, multiplanar cell division in F. muscicola likely depends on FtsZ dosage. Our results lay the groundwork for future studies on cytoskeletal proteins in morphologically complex cyanobacteria.
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Affiliation(s)
| | - Julia Weissenbach
- Institute of General Microbiology, Christian-Albrechts University of Kiel, Germany
| | - Robin Koch
- Institute of General Microbiology, Christian-Albrechts University of Kiel, Germany
| | - Fenna Stücker
- Institute of General Microbiology, Christian-Albrechts University of Kiel, Germany
| | - Karina Stucken
- Institute of General Microbiology, Christian-Albrechts University of Kiel, Germany
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5
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Tarnopol RL, Bowden S, Hinkle K, Balakrishnan K, Nishii A, Kaczmarek CJ, Pawloski T, Vecchiarelli AG. Lessons from a Minimal Genome: What Are the Essential Organizing Principles of a Cell Built from Scratch? Chembiochem 2019; 20:2535-2545. [DOI: 10.1002/cbic.201900249] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Rebecca L. Tarnopol
- Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor MI 48109 USA
| | - Sierra Bowden
- Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor MI 48109 USA
| | - Kevin Hinkle
- Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor MI 48109 USA
| | - Krithika Balakrishnan
- Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor MI 48109 USA
| | - Akira Nishii
- Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor MI 48109 USA
| | - Caleb J. Kaczmarek
- Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor MI 48109 USA
| | - Tara Pawloski
- Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor MI 48109 USA
| | - Anthony G. Vecchiarelli
- Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor MI 48109 USA
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6
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Halbedel S, Lewis RJ. Structural basis for interaction of DivIVA/GpsB proteins with their ligands. Mol Microbiol 2019; 111:1404-1415. [PMID: 30887576 DOI: 10.1111/mmi.14244] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2019] [Indexed: 01/06/2023]
Abstract
DivIVA proteins and their GpsB homologues are late cell division proteins found in Gram-positive bacteria. DivIVA/GpsB proteins associate with the inner leaflet of the cytosolic membrane and act as scaffolds for other proteins required for cell growth and division. DivIVA/GpsB proteins comprise an N-terminal lipid-binding domain for membrane association fused to C-terminal domains supporting oligomerization. Despite sharing the same domain organization, DivIVA and GpsB serve different cellular functions: DivIVA plays diverse roles in division site selection, chromosome segregation and controlling peptidoglycan homeostasis, whereas GpsB contributes to the spatiotemporal control of penicillin-binding protein activity. The crystal structures of the lipid-binding domains of DivIVA from Bacillus subtilis and GpsB from several species share a fold unique to this group of proteins, whereas the C-terminal domains of DivIVA and GpsB are radically different. A number of pivotal features identified from the crystal structures explain the functional differences between the proteins. Herein we discuss these structural and functional relationships and recent advances in our understanding of how DivIVA/GpsB proteins bind and recruit their interaction partners, knowledge that might be useful for future structure-based DivIVA/GpsB inhibitor design.
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Affiliation(s)
- Sven Halbedel
- FG11 Division of Enteropathogenic bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
| | - Richard J Lewis
- Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle upon Tyne, NE2 4HH, United Kingdom
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7
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Vollmer W, Massidda O, Tomasz A. The Cell Wall of Streptococcus pneumoniae. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0018-2018. [PMID: 31172911 PMCID: PMC11026078 DOI: 10.1128/microbiolspec.gpp3-0018-2018] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Indexed: 12/13/2022] Open
Abstract
Streptococcus pneumoniae has a complex cell wall that plays key roles in cell shape maintenance, growth and cell division, and interactions with components of the human host. The peptidoglycan has a heterogeneous composition with more than 50 subunits (muropeptides)-products of several peptidoglycan-modifying enzymes. The amidation of glutamate residues in the stem peptide is needed for efficient peptide cross-linking, and peptides with a dipeptide branch prevail in some beta-lactam-resistant strains. The glycan strands are modified by deacetylation of N-acetylglucosamine residues and O-acetylation of N-acetylmuramic acid residues, and both modifications contribute to pneumococcal resistance to lysozyme. The glycan strands carry covalently attached wall teichoic acid and capsular polysaccharide. Pneumococci are unique in that the wall teichoic acid and lipoteichoic acid contain the same unusually complex repeating units decorated with phosphoryl choline residues, which anchor the choline-binding proteins. The structures of lipoteichoic acid and the attachment site of wall teichoic acid to peptidoglycan have recently been revised. During growth, pneumococci assemble their cell walls at midcell in coordinated rounds of cell elongation and division, leading to the typical ovococcal cell shape. Cell wall growth depends on the cytoskeletal FtsA and FtsZ proteins and is regulated by several morphogenesis proteins that also show patterns of dynamic localization at midcell. Some of the key regulators are phosphorylated by StkP and dephosphorylated by PhpP to facilitate robust selection of the division site and plane and to maintain cell shape.
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Affiliation(s)
- Waldemar Vollmer
- Institute for Cell and Molecular Biosciences, The Centre for Bacterial Cell Biology, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Orietta Massidda
- Department of Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy
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8
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Bergé M, Viollier PH. End-in-Sight: Cell Polarization by the Polygamic Organizer PopZ. Trends Microbiol 2017; 26:363-375. [PMID: 29198650 DOI: 10.1016/j.tim.2017.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 11/02/2017] [Accepted: 11/09/2017] [Indexed: 12/18/2022]
Abstract
Understanding how asymmetries in cellular constituents are achieved and how such positional information directs the construction of structures in a nonrandom fashion is a fundamental problem in cell biology. The recent identification of determinants that self-assemble into macromolecular complexes at the bacterial cell pole provides new insight into the underlying organizational principles in bacterial cells. Specifically, polarity studies in host-associated or free-living α-proteobacteria, a lineage of Gram-negative (diderm) bacteria, reveals that functional and cytological mono- and bipolarity is often conferred by the multivalent polar organizer PopZ, originally identified as a component of a polar chromosome anchor in the cell cycle model system Caulobacter crescentus. PopZ-dependent polarization appears to be widespread and also functional in obligate intracellular pathogens. Here, we discuss how PopZ polarization and the establishment of polar complexes occurs, and we detail the physiological roles of these complexes.
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Affiliation(s)
- Matthieu Bergé
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Rue Michel Servet 1, CH-1211 Geneva, Switzerland.
| | - Patrick H Viollier
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Rue Michel Servet 1, CH-1211 Geneva, Switzerland.
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9
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Vega-Cabrera LA, Wood CD, Pardo-López L. Spo0M: structure and function beyond regulation of sporulation. Curr Genet 2017; 64:17-23. [PMID: 28577219 DOI: 10.1007/s00294-017-0718-3] [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: 05/11/2017] [Revised: 05/23/2017] [Accepted: 05/27/2017] [Indexed: 11/29/2022]
Abstract
In this mini-review, we present a perspective on the recent findings relating Spo0M structure and function that will stimulate and guide further studies in the characterization of this interesting protein. Cell division and sporulation constitute two of the best studied processes in the model organism Bacillus subtilis; however, there are many missing pieces in the giant regulatory puzzle that governs the independent and shared networks between them. Spo0M is a little studied protein that has been related to both, cell division and sporulation, but its biochemical function and its direct interactions have not been yet defined. Structural analysis of Spo0M revealed the presence of an arrestin-like domain and an FP domain (a dimerization domain present in proteasome elements), motifs more commonly found in eukaryotic proteins. The aim of this perspective is to present open questions regarding the functional and structural features of Spo0M that make this protein a good candidate for the ancestor of arrestins in bacteria and an important element in developmental and differentiation processes of Bacillus subtilis.
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Affiliation(s)
- Luz Adriana Vega-Cabrera
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad #2001, Apdo. Postal 510-3, 62250, Cuernavaca, Morelos, Mexico
| | - Christopher D Wood
- Laboratorio Nacional de Microscopía Avanzada, Universidad Nacional Autónoma de México, Av. Universidad #2001, Apdo. Postal 510-3, 62250, Cuernavaca, Morelos, Mexico
| | - Liliana Pardo-López
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad #2001, Apdo. Postal 510-3, 62250, Cuernavaca, Morelos, Mexico.
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10
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Rued BE, Zheng JJ, Mura A, Tsui HCT, Boersma MJ, Mazny JL, Corona F, Perez AJ, Fadda D, Doubravová L, Buriánková K, Branny P, Massidda O, Winkler ME. Suppression and synthetic-lethal genetic relationships of ΔgpsB mutations indicate that GpsB mediates protein phosphorylation and penicillin-binding protein interactions in Streptococcus pneumoniae D39. Mol Microbiol 2017; 103:931-957. [PMID: 28010038 DOI: 10.1111/mmi.13613] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2016] [Indexed: 01/06/2023]
Abstract
GpsB regulatory protein and StkP protein kinase have been proposed as molecular switches that balance septal and peripheral (side-wall like) peptidoglycan (PG) synthesis in Streptococcus pneumoniae (pneumococcus); yet, mechanisms of this switching remain unknown. We report that ΔdivIVA mutations are not epistatic to ΔgpsB division-protein mutations in progenitor D39 and related genetic backgrounds; nor is GpsB required for StkP localization or FDAA labeling at septal division rings. However, we confirm that reduction of GpsB amount leads to decreased protein phosphorylation by StkP and report that the essentiality of ΔgpsB mutations is suppressed by inactivation of PhpP protein phosphatase, which concomitantly restores protein phosphorylation levels. ΔgpsB mutations are also suppressed by other classes of mutations, including one that eliminates protein phosphorylation and may alter division. Moreover, ΔgpsB mutations are synthetically lethal with Δpbp1a, but not Δpbp2a or Δpbp1b mutations, suggesting GpsB activation of PBP2a activity. Consistent with this result, co-IP experiments showed that GpsB complexes with EzrA, StkP, PBP2a, PBP2b and MreC in pneumococcal cells. Furthermore, depletion of GpsB prevents PBP2x migration to septal centers. These results support a model in which GpsB negatively regulates peripheral PG synthesis by PBP2b and positively regulates septal ring closure through its interactions with StkP-PBP2x.
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Affiliation(s)
- Britta E Rued
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA
| | - Jiaqi J Zheng
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA
| | - Andrea Mura
- Dipartimento di Scienze Chirurgiche, Università di Cagliari, Cagliari, 09100, Italy.,Cell and Molecular Microbiology Division, Institute of Microbiology, v.v.i, Academy of Sciences of the Czech Republic, Prague 4, 142 20, Czech Republic
| | - Ho-Ching T Tsui
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA
| | - Michael J Boersma
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA
| | - Jeffrey L Mazny
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA
| | - Federico Corona
- Dipartimento di Scienze Chirurgiche, Università di Cagliari, Cagliari, 09100, Italy
| | - Amilcar J Perez
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA
| | - Daniela Fadda
- Dipartimento di Scienze Chirurgiche, Università di Cagliari, Cagliari, 09100, Italy
| | - Linda Doubravová
- Cell and Molecular Microbiology Division, Institute of Microbiology, v.v.i, Academy of Sciences of the Czech Republic, Prague 4, 142 20, Czech Republic
| | - Karolína Buriánková
- Cell and Molecular Microbiology Division, Institute of Microbiology, v.v.i, Academy of Sciences of the Czech Republic, Prague 4, 142 20, Czech Republic
| | - Pavel Branny
- Cell and Molecular Microbiology Division, Institute of Microbiology, v.v.i, Academy of Sciences of the Czech Republic, Prague 4, 142 20, Czech Republic
| | - Orietta Massidda
- Dipartimento di Scienze Chirurgiche, Università di Cagliari, Cagliari, 09100, Italy
| | - Malcolm E Winkler
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA
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11
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Groundwater PW, Narlawar R, Liao VWY, Bhattacharya A, Srivastava S, Kunal K, Doddareddy M, Oza PM, Mamidi R, Marrs ECL, Perry JD, Hibbs DE, Panda D. A Carbocyclic Curcumin Inhibits Proliferation of Gram-Positive Bacteria by Targeting FtsZ. Biochemistry 2017; 56:514-524. [DOI: 10.1021/acs.biochem.6b00879] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Paul W. Groundwater
- Faculty
of Pharmacy, The University of Sydney, Pharmacy and Bank Building, Science
Road, Sydney, NSW 2006, Australia
| | - Rajeshwar Narlawar
- Faculty
of Pharmacy, The University of Sydney, Pharmacy and Bank Building, Science
Road, Sydney, NSW 2006, Australia
| | - Vivian Wan Yu Liao
- Faculty
of Pharmacy, The University of Sydney, Pharmacy and Bank Building, Science
Road, Sydney, NSW 2006, Australia
| | - Anusri Bhattacharya
- Department
of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Shalini Srivastava
- Department
of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Kishore Kunal
- Department
of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Munikumar Doddareddy
- Faculty
of Pharmacy, The University of Sydney, Pharmacy and Bank Building, Science
Road, Sydney, NSW 2006, Australia
| | - Pratik M. Oza
- Faculty
of Pharmacy, The University of Sydney, Pharmacy and Bank Building, Science
Road, Sydney, NSW 2006, Australia
| | - Ramesh Mamidi
- Faculty
of Pharmacy, The University of Sydney, Pharmacy and Bank Building, Science
Road, Sydney, NSW 2006, Australia
| | - Emma C. L. Marrs
- Microbiology
Department, Freeman Hospital, High Heaton, Newcastle upon Tyne NE7 7DN, United Kingdom
| | - John D. Perry
- Microbiology
Department, Freeman Hospital, High Heaton, Newcastle upon Tyne NE7 7DN, United Kingdom
| | - David E. Hibbs
- Faculty
of Pharmacy, The University of Sydney, Pharmacy and Bank Building, Science
Road, Sydney, NSW 2006, Australia
| | - Dulal Panda
- Department
of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
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12
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Abstract
For years intermediate filaments (IF), belonging to the third class of filamentous cytoskeletal proteins alongside microtubules and actin filaments, were thought to be exclusive to metazoan cells. Structurally these eukaryote IFs are very well defined, consisting of globular head and tail domains, which flank the central rod-domain. This central domain is dominated by an α-helical secondary structure predisposed to form the characteristic coiled-coil, parallel homo-dimer. These elementary dimers can further associate, both laterally and longitudinally, generating a variety of filament-networks built from filaments in the range of 10 nm in diameter. The general role of these filaments with their characteristic mechano-elastic properties both in the cytoplasm and in the nucleus of eukaryote cells is to provide mechanical strength and a scaffold supporting diverse shapes and cellular functions.Since 2003, after the first bacterial IF-like protein, crescentin was identified, it has been evident that bacteria also employ filamentous networks, other than those built from bacterial tubulin or actin homologues, in order to support their cell shape, growth and, in some cases, division. Intriguingly, compared to their eukaryote counterparts, the group of bacterial IF-like proteins shows much wider structural diversity. The sizes of both the head and tail domains are markedly reduced and there is great variation in the length of the central rod-domain. Furthermore, bacterial rod-domains often lack the sub-domain organisation of eukaryote IFs that is the defining feature of the IF-family. However, the fascinating display of filamentous assemblies, including rope, striated cables and hexagonal laces together with the conditions required for their formation both in vitro and in vivo strongly resemble that of eukaryote IFs suggesting that these bacterial proteins are deservedly classified as part of the IF-family and that the current definition should be relaxed slightly to allow their inclusion. The lack of extensive head and tail domains may well make the bacterial proteins more amenable for structural characterisation, which will be essential for establishing the mechanism for their association into filaments. What is more, the well-developed tools for bacterial manipulations provide an excellent opportunity of studying the bacterial systems with the prospect of making significant progress in our understanding of the general underlying principles of intermediate filament assemblies.
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Affiliation(s)
- Gabriella H Kelemen
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
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13
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Bergé M, Campagne S, Mignolet J, Holden S, Théraulaz L, Manley S, Allain FHT, Viollier PH. Modularity and determinants of a (bi-)polarization control system from free-living and obligate intracellular bacteria. eLife 2016; 5. [PMID: 28008852 PMCID: PMC5182065 DOI: 10.7554/elife.20640] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 12/07/2016] [Indexed: 11/24/2022] Open
Abstract
Although free-living and obligate intracellular bacteria are both polarized it is unclear whether the underlying polarization mechanisms and effector proteins are conserved. Here we dissect at the cytological, functional and structural level a conserved polarization module from the free living α-proteobacterium Caulobacter crescentus and an orthologous system from an obligate intracellular (rickettsial) pathogen. The NMR solution structure of the zinc-finger (ZnR) domain from the bifunctional and bipolar ZitP pilus assembly/motility regulator revealed conserved interaction determinants for PopZ, a bipolar matrix protein that anchors the ParB centromere-binding protein and other regulatory factors at the poles. We show that ZitP regulates cytokinesis and the localization of ParB and PopZ, targeting PopZ independently of the previously known binding sites for its client proteins. Through heterologous localization assays with rickettsial ZitP and PopZ orthologs, we document the shared ancestries, activities and structural determinants of a (bi-)polarization system encoded in free-living and obligate intracellular α-proteobacteria. DOI:http://dx.doi.org/10.7554/eLife.20640.001
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Affiliation(s)
- Matthieu Bergé
- Department Microbiology and Molecular Medicine, Institute of Genetics and Genomics in Geneva, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Sébastien Campagne
- Institute of Molecular Biology and Biophysics, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland
| | - Johann Mignolet
- Department Microbiology and Molecular Medicine, Institute of Genetics and Genomics in Geneva, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Seamus Holden
- Laboratory of Experimental Biophysics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Laurence Théraulaz
- Department Microbiology and Molecular Medicine, Institute of Genetics and Genomics in Geneva, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Suliana Manley
- Laboratory of Experimental Biophysics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Frédéric H-T Allain
- Institute of Molecular Biology and Biophysics, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland
| | - Patrick H Viollier
- Department Microbiology and Molecular Medicine, Institute of Genetics and Genomics in Geneva, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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14
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On the mobility, membrane location and functionality of mechanosensitive channels in Escherichia coli. Sci Rep 2016; 6:32709. [PMID: 27596282 PMCID: PMC5011748 DOI: 10.1038/srep32709] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 08/12/2016] [Indexed: 11/23/2022] Open
Abstract
Bacterial mechanosensitive channels protect cells from structural damage during hypoosmotic shock. MscS, MscL and MscK are the most abundant channels in E. coli and arguably the most important ones in osmoprotection. By combining physiological assays with quantitative photo-activated localization microscopy (qPALM), we find an almost linear relationship between channel abundance and cell survival. A minimum of 100 MscL (or MscS) channels is needed for protection when a single type of channel is expressed. Under native-like conditions MscL, MscS as well as MscK distribute homogeneously over the cytoplasmic membrane and the lateral diffusion of the channels is in accordance with their relative protein mass. However, we observe cluster formation and a reduced mobility of MscL when the majority of the subunits of the pentameric channel contain the fluorescent mEos3.2 protein. These data provide new insights into the quantitative biology of mechanosensitive channels and emphasizes the need for care in analysing protein complexes even when the fluorescent tag has been optimized for monomeric behaviour.
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15
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Kloosterman TG, Lenarcic R, Willis CR, Roberts DM, Hamoen LW, Errington J, Wu LJ. Complex polar machinery required for proper chromosome segregation in vegetative and sporulating cells of Bacillus subtilis. Mol Microbiol 2016; 101:333-50. [PMID: 27059541 PMCID: PMC4949633 DOI: 10.1111/mmi.13393] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/04/2016] [Accepted: 04/04/2016] [Indexed: 01/16/2023]
Abstract
Chromosome segregation is an essential process of cell multiplication. In prokaryotes, segregation starts with the newly replicated sister origins of replication, oriCs, which move apart to defined positions in the cell. We have developed a genetic screen to identify mutants defective in placement of oriC during spore development in the Gram‐positive bacterium Bacillus subtilis. In addition to the previously identified proteins Soj and DivIVA, our screen identified several new factors involved in polar recruitment of oriC: a reported regulator of competence ComN, and the regulators of division site selection MinD and MinJ. Previous work implicated Soj as an important regulator of oriC positioning in the cell. Our results suggest a model in which the DivIVA‐interacting proteins ComN and MinJ recruit MinD to the cell pole, and that these proteins work upstream of Soj to enable oriC placement. We show that these proteins form a polar complex, which acts in parallel with but distinct from the sporulation‐specific RacA pathway of oriC placement, and also functions during vegetative growth. Our study further shows that MinD has two distinct cell cycle roles, in cell division and chromosome segregation, and highlights that cell probably use multiple parallel mechanisms to ensure accurate chromosome segregation.
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Affiliation(s)
- Tomas G Kloosterman
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne, UK.,Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Rok Lenarcic
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne, UK.,Lek Pharmaceuticals d.d., Menges, Slovenia
| | - Clare R Willis
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - David M Roberts
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Leendert W Hamoen
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne, UK.,Department of Cell Biology & Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Jeff Errington
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Ling J Wu
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, Newcastle upon Tyne, UK
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16
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Abstract
Protein patterns are known to adapt to cell shape and serve as spatial templates that choreograph downstream processes like cell polarity or cell division. However, how can pattern-forming proteins sense and respond to the geometry of a cell, and what mechanistic principles underlie pattern formation? Current models invoke mechanisms based on dynamic instabilities arising from nonlinear interactions between proteins but neglect the influence of the spatial geometry itself. Here, we show that patterns can emerge as a direct result of adaptation to cell geometry, in the absence of dynamical instability. We present a generic reaction module that allows protein densities robustly to adapt to the symmetry of the spatial geometry. The key component is an NTPase protein that cycles between nucleotide-dependent membrane-bound and cytosolic states. For elongated cells, we find that the protein dynamics generically leads to a bipolar pattern, which vanishes as the geometry becomes spherically symmetrical. We show that such a reaction module facilitates universal adaptation to cell geometry by sensing the local ratio of membrane area to cytosolic volume. This sensing mechanism is controlled by the membrane affinities of the different states. We apply the theory to explain AtMinD bipolar patterns in [Formula: see text] EcMinDE Escherichia coli. Due to its generic nature, the mechanism could also serve as a hitherto-unrecognized spatial template in many other bacterial systems. Moreover, the robustness of the mechanism enables self-organized optimization of protein patterns by evolutionary processes. Finally, the proposed module can be used to establish geometry-sensitive protein gradients in synthetic biological systems.
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17
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Abstract
All life demands the temporal and spatial control of essential biological functions. In bacteria, the recent discovery of coordinating elements provides a framework to begin to explain cell growth and division. Here we present the discovery of a supramolecular structure in the membrane of the coccal bacterium Staphylococcus aureus, which leads to the formation of a large-scale pattern across the entire cell body; this has been unveiled by studying the distribution of essential proteins involved in lipid metabolism (PlsY and CdsA). The organization is found to require MreD, which determines morphology in rod-shaped cells. The distribution of protein complexes can be explained as a spontaneous pattern formation arising from the competition between the energy cost of bending that they impose on the membrane, their entropy of mixing, and the geometric constraints in the system. Our results provide evidence for the existence of a self-organized and nonpercolating molecular scaffold involving MreD as an organizer for optimal cell function and growth based on the intrinsic self-assembling properties of biological molecules.
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18
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Magalon A, Alberge F. Distribution and dynamics of OXPHOS complexes in the bacterial cytoplasmic membrane. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1857:198-213. [PMID: 26545610 DOI: 10.1016/j.bbabio.2015.10.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 12/23/2022]
Abstract
Oxidative phosphorylation (OXPHOS) is an essential process for most living organisms mostly sustained by protein complexes embedded in the cell membrane. In order to thrive, cells need to quickly respond to changes in the metabolic demand or in their environment. An overview of the strategies that can be employed by bacterial cells to adjust the OXPHOS outcome is provided. Regulation at the level of gene expression can only provide a means to adjust the OXPHOS outcome to long-term trends in the environment. In addition, the actual view is that bioenergetic membranes are highly compartmentalized structures. This review discusses what is known about the spatial organization of OXPHOS complexes and the timescales at which they occur. As exemplified with the commensal gut bacterium Escherichia coli, three levels of spatial organization are at play: supercomplexes, membrane microdomains and polar assemblies. This review provides a particular focus on whether dynamic spatial organization can fine-tune the OXPHOS through the definition of specialized functional membrane microdomains. Putative mechanisms responsible for spatio-temporal regulation of the OXPHOS complexes are discussed. This article is part of a Special Issue entitled Organization and dynamics of bioenergetic systems in bacteria, edited by Conrad Mullineaux.
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Affiliation(s)
- Axel Magalon
- CNRS, Laboratoire de Chimie Bactérienne (UMR 7283), Institut de Microbiologie de la Méditerranée, 13009 Marseille, France; Aix-Marseille University, UMR 7283, 13009 Marseille, France.
| | - François Alberge
- CNRS, Laboratoire de Chimie Bactérienne (UMR 7283), Institut de Microbiologie de la Méditerranée, 13009 Marseille, France; Aix-Marseille University, UMR 7283, 13009 Marseille, France
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19
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Transmembrane protein sorting driven by membrane curvature. Nat Commun 2015; 6:8728. [PMID: 26522943 PMCID: PMC4632190 DOI: 10.1038/ncomms9728] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 09/25/2015] [Indexed: 12/22/2022] Open
Abstract
The intricate structure of prokaryotic and eukaryotic cells depends on the ability to target proteins to specific cellular locations. In most cases, we have a poor understanding of the underlying mechanisms. A typical example is the assembly of bacterial chemoreceptors at cell poles. Here we show that the classical chemoreceptor TlpA of Bacillus subtilis does not localize according to the consensus stochastic nucleation mechanism but accumulates at strongly curved membrane areas generated during cell division. This preference was confirmed by accumulation at non-septal curved membranes. Localization appears to be an intrinsic property of the protein complex and does not rely on chemoreceptor clustering, as was previously shown for Escherichia coli. By constructing specific amino-acid substitutions, we demonstrate that the preference for strongly curved membranes arises from the curved shape of chemoreceptor trimer of dimers. These findings demonstrate that the intrinsic shape of transmembrane proteins can determine their cellular localization. The accumulation of chemoreceptor proteins at bacterial poles is thought to depend on their clustering into arrays. Strahl et al. show that in Bacillus subtilis, the chemoreceptor TlpA uses high membrane curvature as a spatial cue for polar localization, through the intrinsic curvature sensitivity of the receptor complex.
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20
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Oswald F, L M Bank E, Bollen YJM, Peterman EJG. Imaging and quantification of trans-membrane protein diffusion in living bacteria. Phys Chem Chem Phys 2015; 16:12625-34. [PMID: 24760126 DOI: 10.1039/c4cp00299g] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The cytoplasmic membrane forms the barrier between any cell's interior and the outside world. It contains many proteins that enable essential processes such as the transmission of signals, the uptake of nutrients, and cell division. In the case of prokaryotes, which do not contain intracellular membranes, the cytoplasmic membrane also contains proteins for respiration and protein folding. Mutual interactions and specific localization of these proteins depend on two-dimensional diffusion driven by thermal fluctuations. The experimental investigation of membrane-protein diffusion in bacteria is challenging due to their small size, only a few times larger than the resolution of an optical microscope. Here, we review fluorescence microscopy-based methods to study diffusion of membrane proteins in living bacteria. The main focus is on data-analysis tools to extract diffusion coefficients from single-particle tracking data obtained by single-molecule fluorescence microscopy. We introduce a novel approach, IPODD (inverse projection of displacement distributions), to obtain diffusion coefficients from the usually obtained 2-D projected diffusion trajectories of the highly 3-D curved bacterial membrane. This method provides, in contrast to traditional mean-squared-displacement methods, correct diffusion coefficients and allows unravelling of heterogeneously diffusing populations.
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Affiliation(s)
- Felix Oswald
- LaserLaB Amsterdam, VU University, De Boelelaan 1081, 1081 HV, Amsterdam, Netherlands.
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21
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Structural basis for the geometry-driven localization of a small protein. Proc Natl Acad Sci U S A 2015; 112:E1908-15. [PMID: 25825747 DOI: 10.1073/pnas.1423868112] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In bacteria, certain shape-sensing proteins localize to differently curved membranes. During sporulation in Bacillus subtilis, the only convex (positively curved) surface in the cell is the forespore, an approximately spherical internal organelle. Previously, we demonstrated that SpoVM localizes to the forespore by preferentially adsorbing onto slightly convex membranes. Here, we used NMR and molecular dynamics simulations of SpoVM and a localization mutant (SpoVM(P9A)) to reveal that SpoVM's atypical amphipathic α-helix inserts deeply into the membrane and interacts extensively with acyl chains to sense packing differences in differently curved membranes. Based on binding to spherical supported lipid bilayers and Monte Carlo simulations, we hypothesize that SpoVM's membrane insertion, along with potential cooperative interactions with other SpoVM molecules in the lipid bilayer, drives its preferential localization onto slightly convex membranes. Such a mechanism, which is distinct from that used by high curvature-sensing proteins, may be widely conserved for the localization of proteins onto the surface of cellular organelles.
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22
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Membrane recognition and dynamics of the RNA degradosome. PLoS Genet 2015; 11:e1004961. [PMID: 25647427 PMCID: PMC4372235 DOI: 10.1371/journal.pgen.1004961] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 12/17/2014] [Indexed: 01/07/2023] Open
Abstract
RNase E, which is the central component of the multienzyme RNA degradosome, serves as a scaffold for interaction with other enzymes involved in mRNA degradation including the DEAD-box RNA helicase RhlB. Epifluorescence microscopy under live cell conditions shows that RNase E and RhlB are membrane associated, but neither protein forms cytoskeletal-like structures as reported earlier by Taghbalout and Rothfield. We show that association of RhlB with the membrane depends on a direct protein interaction with RNase E, which is anchored to the inner cytoplasmic membrane through an MTS (Membrane Targeting Sequence). Molecular dynamics simulations show that the MTS interacts with the phospholipid bilayer by forming a stabilized amphipathic α-helix with the helical axis oriented parallel to the plane of the bilayer and hydrophobic side chains buried deep in the acyl core of the membrane. Based on the molecular dynamics simulations, we propose that the MTS freely diffuses in the membrane by a novel mechanism in which a large number of weak contacts are rapidly broken and reformed. TIRFm (Total Internal Reflection microscopy) shows that RNase E in live cells rapidly diffuses over the entire inner membrane forming short-lived foci. Diffusion could be part of a scanning mechanism facilitating substrate recognition and cooperativity. Remarkably, RNase E foci disappear and the rate of RNase E diffusion increases with rifampicin treatment. Control experiments show that the effect of rifampicin is specific to RNase E and that the effect is not a secondary consequence of the shut off of E. coli transcription. We therefore interpret the effect of rifampicin as being due to the depletion of RNA substrates for degradation. We propose a model in which formation of foci and constraints on diffusion arise from the transient clustering of RNase E into cooperative degradation bodies. Recent discoveries that two ribonucleases with major roles in mRNA degradation, RNase E of Escherichia coli and RNase Y of Bacillus subtilis, are localized to the inner cytoplasmic membrane suggest that spatial separation of transcription and mRNA degradation are general features of the bacterial cell. Here we show that RNase E rapidly diffuses over the entire inner membrane forming short-lived foci. Results of molecular dynamics simulations lead us to suggest that RNase E interacts with the lipid membrane by a novel mechanism permitting a high degree of translational freedom. We show that RNA substrate is necessary for the formation of RNase E foci and that formation of foci correlates with constraints on the diffusion of RNase E. We therefore propose that foci are degradation bodies in which several RNase E molecules engage an RNA substrate. The sequestration of the mRNA degradation machinery to the inner cytoplasmic membrane has important consequences for mRNA turnover. This organization likely favors formation of polyribosomes on nascent transcripts before they are exposed to the degradation machinery. Rapid diffusion of RNase E on the inner cytoplasmic membrane could be part of a scanning mechanism that facilitates recognition of cytoplasmic polyribosomes and cooperative degradation of mRNA.
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23
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Kaval KG, Rismondo J, Halbedel S. A function of DivIVA in Listeria monocytogenes division site selection. Mol Microbiol 2014; 94:637-54. [PMID: 25185533 DOI: 10.1111/mmi.12784] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/02/2014] [Indexed: 11/29/2022]
Abstract
The cell division protein DivIVA influences protein transport via the accessory SecA2 secretion route in Listeria monocytogenes. In contrast, DivIVA from the closely related bacterium Bacillus subtilis contributes to division site selection via the MinCDJ system. However, no classical min phenotype, i.e. filamentation and minicell production was observed with a listerial ΔdivIVA mutant. This has prompted the speculation that division site selection is DivIVA-independent in L. monocytogenes. We addressed this question with genetic, cytological and bacterial two-hybrid experiments and the data obtained correct this view. DivIVA not only binds to MinJ but also directly interacts with MinD. Experiments with fluorescently tagged proteins showed that localization of MinC and MinD was clearly DivIVA-dependent, whereas localization of MinJ was not. An impact of DivIVA on cell division was confirmed by careful comparisons of cell size distributions of divIVA and secA2 mutants. Gene deletion studies and epistasis experiments consistently reinforced these findings, and also revealed that MinJ must have a DivIVA-independent function. The frequency of minicell formation is low in L. monocytogenes min mutants. However, since listerial minicells might be useful as carriers for the introduction of therapeutic compounds into eukaryotic cells, we present a strategy how minicell frequency can be increased.
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Affiliation(s)
- Karan Gautam Kaval
- FG11 Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, Burgstrasse 37, 38855, Wernigerode, Germany
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24
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Synthetic Interaction between the TipN Polarity Factor and an AcrAB-Family Efflux Pump Implicates Cell Polarity in Bacterial Drug Resistance. ACTA ACUST UNITED AC 2014; 21:657-65. [DOI: 10.1016/j.chembiol.2014.02.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 02/04/2014] [Accepted: 02/28/2014] [Indexed: 11/23/2022]
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25
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Chandra G, Chater KF. Developmental biology of Streptomyces from the perspective of 100 actinobacterial genome sequences. FEMS Microbiol Rev 2014; 38:345-79. [PMID: 24164321 PMCID: PMC4255298 DOI: 10.1111/1574-6976.12047] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 08/06/2013] [Accepted: 08/20/2013] [Indexed: 12/22/2022] Open
Abstract
To illuminate the evolution and mechanisms of actinobacterial complexity, we evaluate the distribution and origins of known Streptomyces developmental genes and the developmental significance of actinobacteria-specific genes. As an aid, we developed the Actinoblast database of reciprocal blastp best hits between the Streptomyces coelicolor genome and more than 100 other actinobacterial genomes (http://streptomyces.org.uk/actinoblast/). We suggest that the emergence of morphological complexity was underpinned by special features of early actinobacteria, such as polar growth and the coupled participation of regulatory Wbl proteins and the redox-protecting thiol mycothiol in transducing a transient nitric oxide signal generated during physiologically stressful growth transitions. It seems that some cell growth and division proteins of early actinobacteria have acquired greater importance for sporulation of complex actinobacteria than for mycelial growth, in which septa are infrequent and not associated with complete cell separation. The acquisition of extracellular proteins with structural roles, a highly regulated extracellular protease cascade, and additional regulatory genes allowed early actinobacterial stationary phase processes to be redeployed in the emergence of aerial hyphae from mycelial mats and in the formation of spore chains. These extracellular proteins may have contributed to speciation. Simpler members of morphologically diverse clades have lost some developmental genes.
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26
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Renner LD, Eswaramoorthy P, Ramamurthi KS, Weibel DB. Studying biomolecule localization by engineering bacterial cell wall curvature. PLoS One 2013; 8:e84143. [PMID: 24391905 PMCID: PMC3877235 DOI: 10.1371/journal.pone.0084143] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 11/12/2013] [Indexed: 11/22/2022] Open
Abstract
In this article we describe two techniques for exploring the relationship between bacterial cell shape and the intracellular organization of proteins. First, we created microchannels in a layer of agarose to reshape live bacterial cells and predictably control their mean cell wall curvature, and quantified the influence of curvature on the localization and distribution of proteins in vivo. Second, we used agarose microchambers to reshape bacteria whose cell wall had been chemically and enzymatically removed. By combining microstructures with different geometries and fluorescence microscopy, we determined the relationship between bacterial shape and the localization for two different membrane-associated proteins: i) the cell-shape related protein MreB of Escherichia coli, which is positioned along the long axis of the rod-shaped cell; and ii) the negative curvature-sensing cell division protein DivIVA of Bacillus subtilis, which is positioned primarily at cell division sites. Our studies of intracellular organization in live cells of E. coli and B. subtilis demonstrate that MreB is largely excluded from areas of high negative curvature, whereas DivIVA localizes preferentially to regions of high negative curvature. These studies highlight a unique approach for studying the relationship between cell shape and intracellular organization in intact, live bacteria.
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Affiliation(s)
- Lars D. Renner
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Technical University Dresden and the Max-Bergmann-Centre for Biomaterials, Dresden, Germany
| | - Prahathees Eswaramoorthy
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Kumaran S. Ramamurthi
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Douglas B. Weibel
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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27
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Offringa R, Kleine-Vehn J. Cell polarity and development. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2013; 55:786-8. [PMID: 23953999 DOI: 10.1111/jipb.12099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Affiliation(s)
- Remko Offringa
- Molecular and Developmental Genetics, Institute Biology Leiden, Leiden University, Sylvius Laboratory, Sylviusweg 72, 2333, BE, The Netherlands.
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28
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Flärdh K, Richards DM, Hempel AM, Howard M, Buttner MJ. Regulation of apical growth and hyphal branching in Streptomyces. Curr Opin Microbiol 2012; 15:737-43. [PMID: 23153774 DOI: 10.1016/j.mib.2012.10.012] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Revised: 10/15/2012] [Accepted: 10/19/2012] [Indexed: 01/19/2023]
Abstract
The filamentous bacteria Streptomyces grow by tip extension and through the initiation of new branches, and this apical growth is directed by a polarisome-like complex involving the essential polarity protein DivIVA. New branch sites must be marked de novo and, until recently, there was no understanding of how these new sites are selected. Equally, hyphal branching patterns are affected by environmental conditions, but there was no insight into how polar growth and hyphal branching might be regulated in response to external or internal cues. This review focuses on recent discoveries that reveal the principal mechanism of branch site selection in Streptomyces, and the first mechanism to be identified that regulates polarisome behaviour to modulate polar growth and hyphal branching.
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Affiliation(s)
- Klas Flärdh
- Department of Biology, Lund University, 223 62 Lund, Sweden
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