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Junglas B, Hudina E, Schönnenbeck P, Ritter I, Heddier A, Santiago-Schübel B, Huesgen PF, Schneider D, Sachse C. Structural plasticity of bacterial ESCRT-III protein PspA in higher-order assemblies. Nat Struct Mol Biol 2024:10.1038/s41594-024-01359-7. [PMID: 39152237 DOI: 10.1038/s41594-024-01359-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 06/21/2024] [Indexed: 08/19/2024]
Abstract
Eukaryotic members of the endosome sorting complex required for transport-III (ESCRT-III) family have been shown to form diverse higher-order assemblies. The bacterial phage shock protein A (PspA) has been identified as a member of the ESCRT-III superfamily, and PspA homo-oligomerizes to form rod-shaped assemblies. As observed for eukaryotic ESCRT-III, PspA forms tubular assemblies of varying diameters. Using electron cryo-electron microscopy, we determined 61 Synechocystis PspA structures and observed in molecular detail how the structural plasticity of PspA rods is mediated by conformational changes at three hinge regions in the monomer and by the fixed and changing molecular contacts between protomers. Moreover, we reduced and increased the structural plasticity of PspA rods by removing the loop connecting helices α3/α4 and the addition of nucleotides, respectively. Based on our analysis of PspA-mediated membrane remodeling, we suggest that the observed mode of structural plasticity is a prerequisite for the biological function of ESCRT-III members.
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Affiliation(s)
- Benedikt Junglas
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, Jülich, Germany
| | - Esther Hudina
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, Jülich, Germany
- Department of Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Philipp Schönnenbeck
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, Jülich, Germany
- Department of Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Ilona Ritter
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, Jülich, Germany
| | - Anja Heddier
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, Jülich, Germany
- Department of Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Beatrix Santiago-Schübel
- Zentralinstitut für Engineering, Elektronik und Analytik (ZEA-3), Forschungszentrum Jülich, Jülich, Germany
| | - Pitter F Huesgen
- Zentralinstitut für Engineering, Elektronik und Analytik (ZEA-3), Forschungszentrum Jülich, Jülich, Germany
- Cluster of Excellence on Aging-related Disorders (CECAD), Medical Faculty and University Hospital, University of Cologne, Cologne, Germany
- Institute of Biochemistry, Faculty of Mathematics and Natural Sciences, University of Cologne, Cologne, Germany
| | - Dirk Schneider
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Mainz, Germany
- Institute of Molecular Physiology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Carsten Sachse
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, Jülich, Germany.
- Department of Biology, Heinrich Heine University, Düsseldorf, Germany.
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2
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Ravi J, Anantharaman V, Chen SZ, Brenner EP, Datta P, Aravind L, Gennaro ML. The phage shock protein (PSP) envelope stress response: discovery of novel partners and evolutionary history. mSystems 2024; 9:e0084723. [PMID: 38809013 PMCID: PMC11237479 DOI: 10.1128/msystems.00847-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 03/20/2024] [Indexed: 05/30/2024] Open
Abstract
Bacterial phage shock protein (PSP) systems stabilize the bacterial cell membrane and protect against envelope stress. These systems have been associated with virulence, but despite their critical roles, PSP components are not well characterized outside proteobacteria. Using comparative genomics and protein sequence-structure-function analyses, we systematically identified and analyzed PSP homologs, phyletic patterns, domain architectures, and gene neighborhoods. This approach underscored the evolutionary significance of the system, revealing that its core protein PspA (Snf7 in ESCRT outside bacteria) was present in the last universal common ancestor and that this ancestral functionality has since diversified into multiple novel, distinct PSP systems across life. Several novel partners of the PSP system were identified: (i) the Toastrack domain, likely facilitating assembly of sub-membrane stress-sensing and signaling complexes, (ii) the newly defined HTH-associated α-helical signaling domain-PadR-like transcriptional regulator pair system, and (iii) multiple independent associations with ATPase, CesT/Tir-like chaperone, and Band-7 domains in proteins thought to mediate sub-membrane dynamics. Our work also uncovered links between the PSP components and other domains, such as novel variants of SHOCT-like domains, suggesting roles in assembling membrane-associated complexes of proteins with disparate biochemical functions. Results are available at our interactive web app, https://jravilab.org/psp.IMPORTANCEPhage shock proteins (PSP) are virulence-associated, cell membrane stress-protective systems. They have mostly been characterized in Proteobacteria and Firmicutes. We now show that a minimal PSP system was present in the last universal common ancestor that evolved and diversified into newly identified functional contexts. Recognizing the conservation and evolution of PSP systems across bacterial phyla contributes to our understanding of stress response mechanisms in prokaryotes. Moreover, the newly discovered PSP modularity will likely prompt new studies of lineage-specific cell envelope structures, lifestyles, and adaptation mechanisms. Finally, our results validate the use of domain architecture and genetic context for discovery in comparative genomics.
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Affiliation(s)
- Janani Ravi
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Public Health Research Institute, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - Vivek Anantharaman
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, Maryland, USA
| | - Samuel Zorn Chen
- Computer Science Engineering Undergraduate Program, Michigan State University, East Lansing, Michigan, USA
| | - Evan Pierce Brenner
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Pratik Datta
- Public Health Research Institute, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - L. Aravind
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, Maryland, USA
| | - Maria Laura Gennaro
- Public Health Research Institute, Rutgers New Jersey Medical School, Newark, New Jersey, USA
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3
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Nordenskiöld L, Shi X, Korolev N, Zhao L, Zhai Z, Lindman B. Liquid-liquid phase separation (LLPS) in DNA and chromatin systems from the perspective of colloid physical chemistry. Adv Colloid Interface Sci 2024; 326:103133. [PMID: 38547652 DOI: 10.1016/j.cis.2024.103133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 03/11/2024] [Indexed: 04/13/2024]
Abstract
DNA is a highly charged polyelectrolyte and is prone to associative phase separation driven by the presence of multivalent cations, charged surfactants, proteins, polymers and colloids. The process of DNA phase separation induced by positively charged species is often called DNA condensation. Generally, it refers to either intramolecular DNA compaction (coil-globule transition) or intermolecular DNA aggregation with macroscopic phase separation, but the formation of a DNA liquid crystalline system is also displayed. This has traditionally been described by polyelectrolyte theory and qualitative (Flory-Huggins-based) polymer theory approaches. DNA in the cell nucleus is packed into chromatin wound around the histone octamer (a protein complex comprising two copies each of the four histone proteins H2A, H2B, H3 and H4) to form nucleosomes separated by linker DNA. During the last decade, the phenomenon of the formation of biomolecular condensates (dynamic droplets) by liquid-liquid phase separation (LLPS) has emerged as a generally important mechanism for the formation of membraneless organelles from proteins, nucleic acids and their complexes. DNA and chromatin droplet formation through LLPS has recently received much attention by in vitro as well as in vivo studies that established the importance of this for compartmentalisation in the cell nucleus. Here, we review DNA and chromatin LLPS from a general colloid physical chemistry perspective. We start with a general discussion of colloidal phase separation in aqueous solutions and review the original (pre-LLPS era) work on DNA (macroscopic) phase separation for simpler systems with DNA in the presence of multivalent cations and well-defined surfactants and colloids. Following that, we discuss and illustrate the similarities of such macroscopic phase separation with the general behaviour of LLPS droplet formation by associative phase separation for DNA-protein systems, including chromatin; we also note cases of segregative association. The review ends with a discussion of chromatin LLPS in vivo and its physiological significance.
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Affiliation(s)
- Lars Nordenskiöld
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore.
| | - Xiangyan Shi
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China.
| | - Nikolay Korolev
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Lei Zhao
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China
| | - Ziwei Zhai
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China
| | - Björn Lindman
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore; Physical Chemistry, University of Lund, P.O. Box 124, S-221 00 Lund, Sweden; Coimbra Chemistry Centre, Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal.
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4
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Wallart L, Ben Mlouka MA, Saffiedine B, Coquet L, Le H, Hardouin J, Jouenne T, Phan G, Kiefer-Meyer MC, Girard E, Broutin I, Cosette P. BacA: a possible regulator that contributes to the biofilm formation of Pseudomonas aeruginosa. Front Microbiol 2024; 15:1332448. [PMID: 38505547 PMCID: PMC10948618 DOI: 10.3389/fmicb.2024.1332448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 02/12/2024] [Indexed: 03/21/2024] Open
Abstract
Previously, we pointed out in P. aeruginosa PAO1 biofilm cells the accumulation of a hypothetical protein named PA3731 and showed that the deletion of the corresponding gene impacted its biofilm formation capacity. PA3731 belongs to a cluster of 4 genes (pa3732 to pa3729) that we named bac for "Biofilm Associated Cluster." The present study focuses on the PA14_16140 protein, i.e., the PA3732 (BacA) homolog in the PA14 strain. The role of BacA in rhamnolipid secretion, biofilm formation and virulence, was confirmed by phenotypic experiments with a bacA mutant. Additional investigations allow to advance that the bac system involves in fact 6 genes organized in operon, i.e., bacA to bacF. At a molecular level, quantitative proteomic studies revealed an accumulation of the BAC cognate partners by the bacA sessile mutant, suggesting a negative control of BacA toward the bac operon. Finally, a first crystallographic structure of BacA was obtained revealing a structure homologous to chaperones or/and regulatory proteins.
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Affiliation(s)
- Lisa Wallart
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Rouen, France
| | - Mohamed Amine Ben Mlouka
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Rouen, France
- Univ Rouen Normandy, INSERM US 51, CNRS UAR 2026, HeRacLeS PISSARO, Rouen, France
| | - Brahim Saffiedine
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Rouen, France
| | - Laurent Coquet
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Rouen, France
- Univ Rouen Normandy, INSERM US 51, CNRS UAR 2026, HeRacLeS PISSARO, Rouen, France
| | - Hung Le
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Rouen, France
- Univ Rouen Normandy, INSERM US 51, CNRS UAR 2026, HeRacLeS PISSARO, Rouen, France
| | - Julie Hardouin
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Rouen, France
- Univ Rouen Normandy, INSERM US 51, CNRS UAR 2026, HeRacLeS PISSARO, Rouen, France
| | - Thierry Jouenne
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Rouen, France
| | - Gilles Phan
- Paris Cité University, CiTCoM, CNRS, Paris, France
| | - Marie-Christine Kiefer-Meyer
- Univ Rouen Normandie, Normandie Univ, GlycoMEV UR 4358, SFR Normandie Végétal FED 4277, Innovation Chimie Carnot, RMT BESTIM, GDR Chemobiologie, IRIB, Rouen, France
| | - Eric Girard
- Grenoble Alpes University, CNRS, CEA, IBS, Grenoble, France
| | | | - Pascal Cosette
- Univ Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ, PBS UMR 6270, Rouen, France
- Univ Rouen Normandy, INSERM US 51, CNRS UAR 2026, HeRacLeS PISSARO, Rouen, France
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5
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Cyanobacterial membrane dynamics in the light of eukaryotic principles. Biosci Rep 2023; 43:232406. [PMID: 36602300 PMCID: PMC9950537 DOI: 10.1042/bsr20221269] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/23/2022] [Accepted: 01/03/2023] [Indexed: 01/06/2023] Open
Abstract
Intracellular compartmentalization is a hallmark of eukaryotic cells. Dynamic membrane remodeling, involving membrane fission/fusion events, clearly is crucial for cell viability and function, as well as membrane stabilization and/or repair, e.g., during or after injury. In recent decades, several proteins involved in membrane stabilization and/or dynamic membrane remodeling have been identified and described in eukaryotes. Yet, while typically not having a cellular organization as complex as eukaryotes, also bacteria can contain extra internal membrane systems besides the cytoplasmic membranes (CMs). Thus, also in bacteria mechanisms must have evolved to stabilize membranes and/or trigger dynamic membrane remodeling processes. In fact, in recent years proteins, which were initially defined being eukaryotic inventions, have been recognized also in bacteria, and likely these proteins shape membranes also in these organisms. One example of a complex prokaryotic inner membrane system is the thylakoid membrane (TM) of cyanobacteria, which contains the complexes of the photosynthesis light reaction. Cyanobacteria are evolutionary closely related to chloroplasts, and extensive remodeling of the internal membrane systems has been observed in chloroplasts and cyanobacteria during membrane biogenesis and/or at changing light conditions. We here discuss common principles guiding eukaryotic and prokaryotic membrane dynamics and the proteins involved, with a special focus on the dynamics of the cyanobacterial TMs and CMs.
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6
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Phyletic Distribution and Diversification of the Phage Shock Protein Stress Response System in Bacteria and Archaea. mSystems 2022; 7:e0134821. [PMID: 35604119 PMCID: PMC9239133 DOI: 10.1128/msystems.01348-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The PspA protein domain is found in all domains of life, highlighting its central role in Psp networks. To date, all insights into the core functions of Psp responses derive mainly from protein network blueprints representing only three bacterial phyla.
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7
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Qiu Y, Yu S, Wang Y, Xiao L, Pei L, Pu Y, Zhang Y. Photothermal Therapy may be a Double-edge Sword by Inducing the Formation of Bacterial Antibiotic Tolerance. Biomater Sci 2022; 10:1995-2005. [PMID: 35266929 DOI: 10.1039/d1bm01740c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photothermal nanoparticles are thought to be the most potential candidates against infectious disease, by disrupting cell membrane and inhibiting metabolism. However, subpopulation survived with this low-activity state may be endowed...
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Affiliation(s)
- Yun Qiu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
| | - Shimin Yu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
| | - Yulan Wang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
| | - Leyi Xiao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
| | - Linsen Pei
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan 430079, China
| | - Yingying Pu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan 430079, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan 430079, China
| | - Yufeng Zhang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan 430079, China
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8
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Gupta TK, Klumpe S, Gries K, Heinz S, Wietrzynski W, Ohnishi N, Niemeyer J, Spaniol B, Schaffer M, Rast A, Ostermeier M, Strauss M, Plitzko JM, Baumeister W, Rudack T, Sakamoto W, Nickelsen J, Schuller JM, Schroda M, Engel BD. Structural basis for VIPP1 oligomerization and maintenance of thylakoid membrane integrity. Cell 2021; 184:3643-3659.e23. [PMID: 34166613 DOI: 10.1016/j.cell.2021.05.011] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 02/16/2021] [Accepted: 05/10/2021] [Indexed: 12/21/2022]
Abstract
Vesicle-inducing protein in plastids 1 (VIPP1) is essential for the biogenesis and maintenance of thylakoid membranes, which transform light into life. However, it is unknown how VIPP1 performs its vital membrane-remodeling functions. Here, we use cryo-electron microscopy to determine structures of cyanobacterial VIPP1 rings, revealing how VIPP1 monomers flex and interweave to form basket-like assemblies of different symmetries. Three VIPP1 monomers together coordinate a non-canonical nucleotide binding pocket on one end of the ring. Inside the ring's lumen, amphipathic helices from each monomer align to form large hydrophobic columns, enabling VIPP1 to bind and curve membranes. In vivo mutations in these hydrophobic surfaces cause extreme thylakoid swelling under high light, indicating an essential role of VIPP1 lipid binding in resisting stress-induced damage. Using cryo-correlative light and electron microscopy (cryo-CLEM), we observe oligomeric VIPP1 coats encapsulating membrane tubules within the Chlamydomonas chloroplast. Our work provides a structural foundation for understanding how VIPP1 directs thylakoid biogenesis and maintenance.
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Affiliation(s)
- Tilak Kumar Gupta
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Sven Klumpe
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Karin Gries
- Molecular Biotechnology and Systems Biology, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Steffen Heinz
- Department of Molecular Plant Sciences, LMU Munich, 82152 Martinsried, Germany
| | - Wojciech Wietrzynski
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany; Helmholtz Pioneer Campus, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Norikazu Ohnishi
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan
| | - Justus Niemeyer
- Molecular Biotechnology and Systems Biology, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Benjamin Spaniol
- Molecular Biotechnology and Systems Biology, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Miroslava Schaffer
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Anna Rast
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany; Department of Molecular Plant Sciences, LMU Munich, 82152 Martinsried, Germany
| | - Matthias Ostermeier
- Department of Molecular Plant Sciences, LMU Munich, 82152 Martinsried, Germany
| | - Mike Strauss
- Department of Anatomy and Cell Biology, McGill University, Montreal, QC H3A 17C, Canada
| | - Jürgen M Plitzko
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Wolfgang Baumeister
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Till Rudack
- Biospectroscopy, Center for Protein Diagnostics (PRODI), Ruhr University Bochum, 44801 Bochum, Germany; Department of Biophysics, Faculty of Biology & Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany
| | - Wataru Sakamoto
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan
| | - Jörg Nickelsen
- Department of Molecular Plant Sciences, LMU Munich, 82152 Martinsried, Germany
| | - Jan M Schuller
- SYNMIKRO Research Center and Department of Chemistry, Philipps-University Marburg, 35032 Marburg, Germany.
| | - Michael Schroda
- Molecular Biotechnology and Systems Biology, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany.
| | - Benjamin D Engel
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany; Helmholtz Pioneer Campus, Helmholtz Zentrum München, 85764 Neuherberg, Germany; Department of Chemistry, Technical University of Munich, 85748 Garching, Germany.
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9
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Junglas B, Huber ST, Heidler T, Schlösser L, Mann D, Hennig R, Clarke M, Hellmann N, Schneider D, Sachse C. PspA adopts an ESCRT-III-like fold and remodels bacterial membranes. Cell 2021; 184:3674-3688.e18. [PMID: 34166616 DOI: 10.1016/j.cell.2021.05.042] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 03/01/2021] [Accepted: 05/26/2021] [Indexed: 12/31/2022]
Abstract
PspA is the main effector of the phage shock protein (Psp) system and preserves the bacterial inner membrane integrity and function. Here, we present the 3.6 Å resolution cryoelectron microscopy (cryo-EM) structure of PspA assembled in helical rods. PspA monomers adopt a canonical ESCRT-III fold in an extended open conformation. PspA rods are capable of enclosing lipids and generating positive membrane curvature. Using cryo-EM, we visualized how PspA remodels membrane vesicles into μm-sized structures and how it mediates the formation of internalized vesicular structures. Hotspots of these activities are zones derived from PspA assemblies, serving as lipid transfer platforms and linking previously separated lipid structures. These membrane fusion and fission activities are in line with the described functional properties of bacterial PspA/IM30/LiaH proteins. Our structural and functional analyses reveal that bacterial PspA belongs to the evolutionary ancestry of ESCRT-III proteins involved in membrane remodeling.
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Affiliation(s)
- Benedikt Junglas
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany; JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany; Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Stefan T Huber
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Thomas Heidler
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany; JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Lukas Schlösser
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Daniel Mann
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany; JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Raoul Hennig
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Mairi Clarke
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Nadja Hellmann
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Dirk Schneider
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, 55128 Mainz, Germany; Institute of Molecular Physiology, Johannes Gutenberg University Mainz, 55128 Mainz, Germany.
| | - Carsten Sachse
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, ER-C-3/Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany; JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany; Department of Biology, Heinrich Heine University, Universitätsstr. 1, 40225 Düsseldorf, Germany.
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10
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Super-Resolution Fluorescence Microscopy Reveals Clustering Behaviour of Chlamydia pneumoniae's Major Outer Membrane Protein. BIOLOGY 2020; 9:biology9100344. [PMID: 33092039 PMCID: PMC7589890 DOI: 10.3390/biology9100344] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/16/2020] [Accepted: 10/16/2020] [Indexed: 12/20/2022]
Abstract
Chlamydia pneumoniae is a Gram-negative bacterium responsible for a number of human respiratory diseases and linked to some chronic inflammatory diseases. The major outer membrane protein (MOMP) of Chlamydia is a conserved immunologically dominant protein located in the outer membrane, which, together with its surface exposure and abundance, has led to MOMP being the main focus for vaccine and antimicrobial studies in recent decades. MOMP has a major role in the chlamydial outer membrane complex through the formation of intermolecular disulphide bonds, although the exact interactions formed are currently unknown. Here, it is proposed that due to the large number of cysteines available for disulphide bonding, interactions occur between cysteine-rich pockets as opposed to individual residues. Such pockets were identified using a MOMP homology model with a supporting low-resolution (~4 Å) crystal structure. The localisation of MOMP in the E. coli membrane was assessed using direct stochastic optical reconstruction microscopy (dSTORM), which showed a decrease in membrane clustering with cysteine-rich regions containing two mutations. These results indicate that disulphide bond formation was not disrupted by single mutants located in the cysteine-dense regions and was instead compensated by neighbouring cysteines within the pocket in support of this cysteine-rich pocket hypothesis.
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Theis J, Niemeyer J, Schmollinger S, Ries F, Rütgers M, Gupta TK, Sommer F, Muranaka LS, Venn B, Schulz-Raffelt M, Willmund F, Engel BD, Schroda M. VIPP2 interacts with VIPP1 and HSP22E/F at chloroplast membranes and modulates a retrograde signal for HSP22E/F gene expression. PLANT, CELL & ENVIRONMENT 2020; 43:1212-1229. [PMID: 31994740 DOI: 10.1111/pce.13732] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 06/10/2023]
Abstract
VIPP proteins aid thylakoid biogenesis and membrane maintenance in cyanobacteria, algae, and plants. Some members of the Chlorophyceae contain two VIPP paralogs termed VIPP1 and VIPP2, which originate from an early gene duplication event during the evolution of green algae. VIPP2 is barely expressed under nonstress conditions but accumulates in cells exposed to high light intensities or H2 O2 , during recovery from heat stress, and in mutants with defective integration (alb3.1) or translocation (secA) of thylakoid membrane proteins. Recombinant VIPP2 forms rod-like structures in vitro and shows a strong affinity for phosphatidylinositol phosphate. Under stress conditions, >70% of VIPP2 is present in membrane fractions and localizes to chloroplast membranes. A vipp2 knock-out mutant displays no growth phenotypes and no defects in the biogenesis or repair of photosystem II. However, after exposure to high light intensities, the vipp2 mutant accumulates less HSP22E/F and more LHCSR3 protein and transcript. This suggests that VIPP2 modulates a retrograde signal for the expression of nuclear genes HSP22E/F and LHCSR3. Immunoprecipitation of VIPP2 from solubilized cells and membrane-enriched fractions revealed major interactions with VIPP1 and minor interactions with HSP22E/F. Our data support a distinct role of VIPP2 in sensing and coping with chloroplast membrane stress.
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Affiliation(s)
- Jasmine Theis
- Molekulare Biotechnologie & Systembiologie, TU Kaiserslautern, Kaiserslautern, Germany
| | - Justus Niemeyer
- Molekulare Biotechnologie & Systembiologie, TU Kaiserslautern, Kaiserslautern, Germany
| | - Stefan Schmollinger
- Molekulare Biotechnologie & Systembiologie, TU Kaiserslautern, Kaiserslautern, Germany
| | - Fabian Ries
- Molecular Genetics of Eukaryotes, TU Kaiserslautern, Kaiserslautern, Germany
| | - Mark Rütgers
- Molekulare Biotechnologie & Systembiologie, TU Kaiserslautern, Kaiserslautern, Germany
| | - Tilak Kumar Gupta
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Frederik Sommer
- Molekulare Biotechnologie & Systembiologie, TU Kaiserslautern, Kaiserslautern, Germany
| | | | - Benedikt Venn
- Molekulare Biotechnologie & Systembiologie, TU Kaiserslautern, Kaiserslautern, Germany
| | - Miriam Schulz-Raffelt
- Molekulare Biotechnologie & Systembiologie, TU Kaiserslautern, Kaiserslautern, Germany
| | - Felix Willmund
- Molecular Genetics of Eukaryotes, TU Kaiserslautern, Kaiserslautern, Germany
| | - Benjamin D Engel
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Michael Schroda
- Molekulare Biotechnologie & Systembiologie, TU Kaiserslautern, Kaiserslautern, Germany
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Siebenaller C, Junglas B, Schneider D. Functional Implications of Multiple IM30 Oligomeric States. FRONTIERS IN PLANT SCIENCE 2019; 10:1500. [PMID: 31824532 PMCID: PMC6882379 DOI: 10.3389/fpls.2019.01500] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 10/29/2019] [Indexed: 05/03/2023]
Abstract
The inner membrane-associated protein of 30 kDa (IM30), also known as the vesicle-inducing protein in plastids 1 (Vipp1), is essential for photo-autotrophic growth of cyanobacteria, algae and higher plants. While its exact function still remains largely elusive, it is commonly accepted that IM30 is crucially involved in thylakoid membrane biogenesis, stabilization and/or maintenance. A characteristic feature of IM30 is its intrinsic propensity to form large homo-oligomeric protein complexes. 15 years ago, it has been reported that these supercomplexes have a ring-shaped structure. However, the in vivo significance of these ring structures is not finally resolved yet and the formation of more complex assemblies has been reported. We here present and discuss research on IM30 conducted within the past 25 years with a special emphasis on the question of why we potentially need IM30 supercomplexes in vivo.
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Affiliation(s)
| | | | - Dirk Schneider
- Department of Pharmacy and Biochemistry, Johannes Gutenberg University Mainz, Mainz, Germany
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DeAngelis CM, Nag D, Withey JH, Matson JS. Characterization of the Vibrio cholerae Phage Shock Protein Response. J Bacteriol 2019; 201:e00761-18. [PMID: 30858296 PMCID: PMC6597379 DOI: 10.1128/jb.00761-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 02/26/2019] [Indexed: 12/25/2022] Open
Abstract
The phage shock protein (Psp) system is a stress response pathway that senses and responds to inner membrane damage. The genetic components of the Psp system are present in several clinically relevant Gram-negative bacteria, including Vibrio cholerae However, most of the current knowledge about the Psp response stems from in vitro studies in Escherichia coli and Yersinia enterocolitica In fact, the Psp response in V. cholerae has remained completely uncharacterized. In this study, we demonstrate that V. cholerae does have a functional Psp response system. We found that overexpression of GspD (EpsD), the type II secretion system secretin, induces the Psp response, whereas other V. cholerae secretins do not. In addition, we have identified several environmental conditions that induce this stress response. Our studies on the genetic regulation and induction of the Psp system in V. cholerae suggest that the key regulatory elements are conserved with those of other Gram-negative bacteria. While a psp null strain is fully capable of colonizing the infant mouse intestine, it exhibits a colonization defect in a zebrafish model, indicating that this response may be important for disease transmission in the environment. Overall, these studies provide an initial understanding of a stress response pathway that has not been previously investigated in V. choleraeIMPORTANCEVibrio cholerae leads a dual life cycle, as it can exist in the aquatic environment and colonize the human small intestine. In both life cycles, V. cholerae encounters a variety of stressful conditions, including fluctuating pH and temperature and exposure to other agents that may negatively affect cell envelope homeostasis. The phage shock protein (Psp) response is required to sense and respond to such insults in other bacteria but has remained unstudied in V. cholerae Interestingly, the Psp system has protein homologs, principally, PspA, in a number of bacterial clades as well as in archaea and plants. Therefore, our findings not only fill a gap in knowledge about an unstudied extracytoplasmic stress response in V. cholerae, but also may have far-reaching implications.
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Affiliation(s)
- Cara M DeAngelis
- Department of Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Dhrubajyoti Nag
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Jeffrey H Withey
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Jyl S Matson
- Department of Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
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Transcription factor YcjW controls the emergency H 2S production in E. coli. Nat Commun 2019; 10:2868. [PMID: 31253770 PMCID: PMC6599011 DOI: 10.1038/s41467-019-10785-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 06/03/2019] [Indexed: 12/18/2022] Open
Abstract
Prokaryotes and eukaryotes alike endogenously generate the gaseous molecule hydrogen sulfide (H2S). Bacterial H2S acts as a cytoprotectant against antibiotics-induced stress and promotes redox homeostasis. In E. coli, endogenous H2S production is primarily dependent on 3-mercaptopyruvate sulfurtransferase (3MST), encoded by mstA. Here, we show that cells lacking 3MST acquire a phenotypic suppressor mutation resulting in compensatory H2S production and tolerance to antibiotics and oxidative stress. Using whole genome sequencing, we identified a non-synonymous mutation within an uncharacterized LacI-type transcription factor, ycjW. We then mapped regulatory targets of YcjW and discovered it controls the expression of carbohydrate metabolic genes and thiosulfate sulfurtransferase PspE. Induction of pspE expression in the suppressor strain provides an alternative mechanism for H2S biosynthesis. Our results reveal a complex interaction between carbohydrate metabolism and H2S production in bacteria and the role, a hitherto uncharacterized transcription factor, YcjW, plays in linking the two. Hydrogen sulfide (H2S) production in Escherichia coli is controlled by the sulfurtransferase 3MST. Here, the authors describe an alternative mechanism for H2S biosynthesis via activation of the thiosulfate sulfurtransferase PspE, a process mediated by the transcription factor YcjW.
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VIPP1 rods engulf membranes containing phosphatidylinositol phosphates. Sci Rep 2019; 9:8725. [PMID: 31217458 PMCID: PMC6584618 DOI: 10.1038/s41598-019-44259-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 05/14/2019] [Indexed: 12/15/2022] Open
Abstract
In cyanobacteria and plants, VIPP1 plays crucial roles in the biogenesis and repair of thylakoid membrane protein complexes and in coping with chloroplast membrane stress. In chloroplasts, VIPP1 localizes in distinct patterns at or close to envelope and thylakoid membranes. In vitro, VIPP1 forms higher-order oligomers of >1 MDa that organize into rings and rods. However, it remains unknown how VIPP1 oligomerization is related to function. Using time-resolved fluorescence anisotropy and sucrose density gradient centrifugation, we show here that Chlamydomonas reinhardtii VIPP1 binds strongly to liposomal membranes containing phosphatidylinositol-4-phosphate (PI4P). Cryo-electron tomography reveals that VIPP1 oligomerizes into rods that can engulf liposomal membranes containing PI4P. These findings place VIPP1 into a group of membrane-shaping proteins including epsin and BAR domain proteins. Moreover, they point to a potential role of phosphatidylinositols in directing the shaping of chloroplast membranes.
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Thurotte A, Schneider D. The Fusion Activity of IM30 Rings Involves Controlled Unmasking of the Fusogenic Core. FRONTIERS IN PLANT SCIENCE 2019; 10:108. [PMID: 30792728 PMCID: PMC6374351 DOI: 10.3389/fpls.2019.00108] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 01/23/2019] [Indexed: 05/20/2023]
Abstract
The inner membrane-associated protein of 30 kDa (IM30, also known as Vipp1) is required for thylakoid membrane biogenesis and maintenance in cyanobacteria and chloroplasts. The protein forms large rings of ∼2 MDa and triggers membrane fusion in presence of Mg2+. Based on the here presented observations, IM30 rings are built from dimers of dimers, and formation of these tetrameric building blocks is driven by interactions of the central coiled-coil, formed by helices 2 and 3, and stabilized via additional interactions mainly involving helix 1. Furthermore, helix 1 as well as C-terminal regions of IM30 together negatively regulate ring-ring contacts. We propose that IM30 rings represent the inactive form of IM30, and upon binding to negatively charged membrane surfaces, the here identified fusogenic core of IM30 rings eventually interacts with the lipid bilayer, resulting in membrane destabilization and membrane fusion. Unmasking of the IM30 fusogenic core likely is controlled by Mg2+, which triggers rearrangement of the IM30 ring structure.
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17
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Association of Mycobacterium Proteins with Lipid Droplets. J Bacteriol 2018; 200:JB.00240-18. [PMID: 29760207 DOI: 10.1128/jb.00240-18] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 05/07/2018] [Indexed: 12/27/2022] Open
Abstract
Mycobacterium tuberculosis is a global pathogen of significant medical importance. A key aspect of its life cycle is the ability to enter into an altered physiological state of nonreplicating persistence during latency and resist elimination by the host immune system. One mechanism by which M. tuberculosis facilitates its survival during latency is by producing and metabolizing intracytoplasmic lipid droplets (LDs). LDs are quasi-organelles consisting of a neutral lipid core such as triacylglycerol surrounded by a phospholipid monolayer and proteins. We previously reported that PspA (phage shock protein A) associates with LDs produced in Mycobacterium In particular, the loss or overproduction of PspA alters LD homeostasis in Mycobacterium smegmatis and attenuates the survival of M. tuberculosis during nonreplicating persistence. Here, M. tuberculosis PspA (PspAMtb) and a ΔpspA M. smegmatis mutant were used as model systems to investigate the mechanism by which PspA associates with LDs and determine if other Mycobacterium proteins associate with LDs using a mechanism similar to that for PspA. Through this work, we established that the amphipathic helix present in the first α-helical domain (H1) of PspA is both necessary and sufficient for the targeting of this protein to LDs. Furthermore, we identified other Mycobacterium proteins that also possess amphipathic helices similar to PspA H1, including a subset that localize to LDs. Altogether, our results indicate that amphipathic helices may be an important mechanism by which proteins target LDs in prokaryotes.IMPORTANCEMycobacterium spp. are one of the few prokaryotes known to produce lipid droplets (LDs), and their production has been linked to aspects of persistent infection by M. tuberculosis Unfortunately, little is known about LD production in these organisms, including how LDs are formed, their function, or the identity of proteins that associate with them. In this study, an established M. tuberculosis LD protein and a surrogate Mycobacterium host were used as model systems to study the interactions between proteins and LDs in bacteria. Through these studies, we identified a commonly occurring protein motif that is able to facilitate the association of proteins to LDs in prokaryotes.
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Heidrich ES, Brüser T. Evidence for a second regulatory binding site on PspF that is occupied by the C-terminal domain of PspA. PLoS One 2018; 13:e0198564. [PMID: 29906279 PMCID: PMC6003685 DOI: 10.1371/journal.pone.0198564] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 05/21/2018] [Indexed: 11/18/2022] Open
Abstract
PspA is a key component of the bacterial Psp membrane-stress response system. The biochemical and functional characterization of PspA is impeded by its oligomerization and aggregation properties. It was recently possible to solve the coiled coil structure of a completely soluble PspA fragment, PspA(1–144), that associates with the σ54 enhancer binding protein PspF at its W56-loop and thereby down-regulates the Psp response. We now found that the C-terminal part of PspA, PspA(145–222), also interacts with PspF and inhibits its activity in the absence of full-length PspA. Surprisingly, PspA(145–222) effects changed completely in the presence of full-length PspA, as promoter activity was triggered instead of being inhibited under this condition. PspA(145–222) thus interfered with the inhibitory effect of full-length PspA on PspF, most likely by interacting with full-length PspA that remained bound to PspF. In support of this view, a comprehensive bacterial-2-hybrid screen as well as co-purification analyses indicated a self-interaction of PspA(145–222) and an interaction with full-length PspA. This is the first direct demonstration of PspA/PspA and PspA/PspF interactions in vivo that are mediated by the C-terminus of PspA. The data indicate that regulatory binding sites on PspF do not only exist for the N-terminal coiled coil domain but also for the C-terminal domain of PspA. The inhibition of PspF by PspA-(145–222) was reduced upon membrane stress, whereas the inhibition of PspF by PspA(1–144) did not respond to membrane stress. We therefore propose that the C-terminal domain of PspA is crucial for the regulation of PspF in response to Psp system stimuli.
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Affiliation(s)
| | - Thomas Brüser
- From the Institute of Microbiology, Leibniz Universität Hannover, Hannover, Germany
- * E-mail:
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19
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Abstract
Peptidoglycan is an essential component of the cell wall that protects bacteria from environmental stress. A carefully coordinated biosynthesis of peptidoglycan during cell elongation and division is required for cell viability. This biosynthesis involves sophisticated enzyme machineries that dynamically synthesize, remodel, and degrade peptidoglycan. However, when and where bacteria build peptidoglycan, and how this is coordinated with cell growth, have been long-standing questions in the field. The improvement of microscopy techniques has provided powerful approaches to study peptidoglycan biosynthesis with high spatiotemporal resolution. Recent development of molecular probes further accelerated the growth of the field, which has advanced our knowledge of peptidoglycan biosynthesis dynamics and mechanisms. Here, we review the technologies for imaging the bacterial cell wall and its biosynthesis activity. We focus on the applications of fluorescent d-amino acids, a newly developed type of probe, to visualize and study peptidoglycan synthesis and dynamics, and we provide direction for prospective research.
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Affiliation(s)
- Atanas D Radkov
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.,Current affiliation: Biophysics and Biochemistry Department, University of California, San Francisco, California 94158, USA;
| | - Yen-Pang Hsu
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA; , ,
| | - Garrett Booher
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA; , ,
| | - Michael S VanNieuwenhze
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.,Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405, USA; , ,
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Abstract
The bacterial cytoplasmic membrane is composed of roughly equal proportions of lipids and proteins. The main lipid components are phospholipids, which vary in acyl chain length, saturation, and branching and carry head groups that vary in size and charge. Phospholipid variants determine membrane properties such as fluidity and charge that in turn modulate interactions with membrane-associated proteins. We summarize recent advances in understanding bacterial membrane structure and function, focusing particularly on the possible existence and significance of specialized membrane domains. We review the role of membrane curvature as a spatial cue for recruitment and regulation of proteins involved in morphogenic functions, especially elongation and division. Finally, we examine the role of the membrane, especially regulation of synthesis and fluid properties, in the life cycle of cell wall-deficient L-form bacteria.
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Affiliation(s)
- Henrik Strahl
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle Upon Tyne, NE2 4AX United Kingdom; ,
| | - Jeff Errington
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle Upon Tyne, NE2 4AX United Kingdom; ,
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Thurotte A, Brüser T, Mascher T, Schneider D. Membrane chaperoning by members of the PspA/IM30 protein family. Commun Integr Biol 2017. [PMCID: PMC5333519 DOI: 10.1080/19420889.2016.1264546] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
PspA, IM30 (Vipp1) and LiaH, which all belong to the PspA/IM30 protein family, form high molecular weight oligomeric structures. For all proteins membrane binding and protection of the membrane structure and integrity has been shown or postulated. Here we discuss the possible membrane chaperoning activity of PspA, IM30 and LiaH and propose that larger oligomeric structures bind to stressed membrane regions, followed by oligomer disassembly and membrane stabilization by protein monomers or smaller/different oligomeric scaffolds.
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Affiliation(s)
- Adrien Thurotte
- Institut für Pharmazie und Biochemie, Johannes Gutenberg-Universität Mainz, Mainz, Germany
| | - Thomas Brüser
- Institut für Mikrobiologie, Leibniz Universität Hannover, Hannover, Germany
| | - Thorsten Mascher
- Institut für Mikrobiologie, Technische Universität Dresden, Dresden, Germany
| | - Dirk Schneider
- Institut für Pharmazie und Biochemie, Johannes Gutenberg-Universität Mainz, Mainz, Germany
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Structure and function of PspA and Vipp1 N-terminal peptides: Insights into the membrane stress sensing and mitigation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:28-39. [DOI: 10.1016/j.bbamem.2016.10.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 10/18/2016] [Accepted: 10/27/2016] [Indexed: 12/20/2022]
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Manganelli R, Gennaro ML. Protecting from Envelope Stress: Variations on the Phage-Shock-Protein Theme. Trends Microbiol 2016; 25:205-216. [PMID: 27865622 DOI: 10.1016/j.tim.2016.10.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 10/16/2016] [Accepted: 10/24/2016] [Indexed: 01/03/2023]
Abstract
During envelope stress, critical inner-membrane functions are preserved by the phage-shock-protein (Psp) system, a stress response that emerged from work with Escherichia coli and other Gram-negative bacteria. Reciprocal regulatory interactions and multiple effector functions are well documented in these organisms. Searches for the Psp system across phyla reveal conservation of only one protein, PspA. However, examination of Firmicutes and Actinobacteria reveals that PspA orthologs associate with non-orthologous regulatory and effector proteins retaining functions similar to those in Gram-negative counterparts. Conservation across phyla emphasizes the long-standing importance of the Psp system in prokaryotes, while inter- and intra-phyla variations within the system indicate adaptation to different cell envelope structures, bacterial lifestyles, and/or bacterial morphogenetic strategies.
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Affiliation(s)
| | - Maria Laura Gennaro
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, New Jersey 07103, USA.
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Heidrich J, Thurotte A, Schneider D. Specific interaction of IM30/Vipp1 with cyanobacterial and chloroplast membranes results in membrane remodeling and eventually in membrane fusion. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1859:537-549. [PMID: 27693914 DOI: 10.1016/j.bbamem.2016.09.025] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 09/19/2016] [Accepted: 09/21/2016] [Indexed: 12/22/2022]
Abstract
The photosynthetic light reaction takes place within the thylakoid membrane system in cyanobacteria and chloroplasts. Besides its global importance, the biogenesis, maintenance and dynamics of this membrane system are still a mystery. In the last two decades, strong evidence supported the idea that these processes involve IM30, the inner membrane-associated protein of 30kDa, a protein also known as the vesicle-inducing protein in plastids 1 (Vipp1). Even though we just only begin to understand the precise physiological function of this protein, it is clear that interaction of IM30 with membranes is crucial for biogenesis of thylakoid membranes. Here we summarize and discuss forces guiding IM30-membrane interactions, as the membrane properties as well as the oligomeric state of IM30 appear to affect proper interaction of IM30 with membrane surfaces. Interaction of IM30 with membranes results in an altered membrane structure and can finally trigger fusion of adjacent membranes, when Mg2+ is present. Based on recent results, we finally present a model summarizing individual steps involved in IM30-mediated membrane fusion. This article is part of a Special Issue entitled: Lipid order/lipid defects and lipid-control of protein activity edited by Dirk Schneider.
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Affiliation(s)
- Jennifer Heidrich
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg-University Mainz, Johann-Joachim-Becher-Weg 30, 55128 Mainz, Germany
| | - Adrien Thurotte
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg-University Mainz, Johann-Joachim-Becher-Weg 30, 55128 Mainz, Germany
| | - Dirk Schneider
- Institute of Pharmacy and Biochemistry, Johannes Gutenberg-University Mainz, Johann-Joachim-Becher-Weg 30, 55128 Mainz, Germany.
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Abstract
The phage shock protein (Psp) system was identified as a response to phage infection in Escherichia coli, but rather than being a specific response to a phage, it detects and mitigates various problems that could increase inner-membrane (IM) permeability. Interest in the Psp system has increased significantly in recent years due to appreciation that Psp-like proteins are found in all three domains of life and because the bacterial Psp response has been linked to virulence and other important phenotypes. In this article, we summarize our current understanding of what the Psp system detects and how it detects it, how four core Psp proteins form a signal transduction cascade between the IM and the cytoplasm, and current ideas that explain how the Psp response keeps bacterial cells alive. Although recent studies have significantly improved our understanding of this system, it is an understanding that is still far from complete.
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Affiliation(s)
- Josué Flores-Kim
- Department of Microbiology, New York University School of Medicine, New York, NY 10016; ,
| | - Andrew J Darwin
- Department of Microbiology, New York University School of Medicine, New York, NY 10016; ,
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Zhang N, Jovanovic G, McDonald C, Ces O, Zhang X, Buck M. Transcription Regulation and Membrane Stress Management in Enterobacterial Pathogens. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 915:207-30. [DOI: 10.1007/978-3-319-32189-9_13] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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27
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Southern SJ, Male A, Milne T, Sarkar-Tyson M, Tavassoli A, Oyston PCF. Evaluating the role of phage-shock protein A in Burkholderia pseudomallei. MICROBIOLOGY-SGM 2015; 161:2192-203. [PMID: 26374246 PMCID: PMC5452601 DOI: 10.1099/mic.0.000175] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The phage-shock protein (Psp) response is an extracytoplasmic response system that is vital for maintenance of the cytoplasmic membrane when the cell encounters stressful conditions. The paradigm of the Psp response has been established in Escherichia coli. The response has been shown to be important for survival during the stationary phase, maintenance of the proton motive force across membranes and implicated in virulence. In this study, we identified a putative PspA homologue in Burkholderia pseudomallei, annotated as BPSL2105. Similar to the induction of PspA in E. coli, the expression of B. pseudomallei BPSL2105 was induced by heat shock. Deletion of BPSL2105 resulted in a survival defect in the late stationary phase coincident with dramatic changes in the pH of the culture medium. The B. pseudomallei BPSL2105 deletion mutant also displayed reduced survival in macrophage infection – the first indication that the Psp response plays a role during intracellular pathogenesis in this species. The purified protein formed large oligomeric structures similar to those observed for the PspA protein of E. coli, and PspA homologues in Bacillus, cyanobacteria and higher plants, providing further evidence to support the identification of BPSL2105 as a PspA-like protein in B. pseudomallei.
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Affiliation(s)
- Stephanie J Southern
- 1Biomedical Sciences, Defence Science and Technology Laboratory, Porton Down, Salisbury, UK
| | - Abigail Male
- 2Department of Chemistry, University of Southampton, Southampton, UK
| | - Timothy Milne
- 1Biomedical Sciences, Defence Science and Technology Laboratory, Porton Down, Salisbury, UK
| | - Mitali Sarkar-Tyson
- 1Biomedical Sciences, Defence Science and Technology Laboratory, Porton Down, Salisbury, UK 3University of Western Australia, QEII Medical Centre, Nedlands, Western Australia, Australia
| | - Ali Tavassoli
- 2Department of Chemistry, University of Southampton, Southampton, UK 4The Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Petra C F Oyston
- 1Biomedical Sciences, Defence Science and Technology Laboratory, Porton Down, Salisbury, UK
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Osadnik H, Schöpfel M, Heidrich E, Mehner D, Lilie H, Parthier C, Risselada HJ, Grubmüller H, Stubbs MT, Brüser T. PspF-binding domain PspA1-144and the PspA·F complex: New insights into the coiled-coil-dependent regulation of AAA+ proteins. Mol Microbiol 2015; 98:743-59. [DOI: 10.1111/mmi.13154] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2015] [Indexed: 02/05/2023]
Affiliation(s)
- Hendrik Osadnik
- Institute of Microbiology; Leibniz Universität Hannover; Herrenhäuser Str. 2 Hannover 30419 Germany
| | - Michael Schöpfel
- Institute of Biochemistry and Biotechnology; Martin-Luther University Halle-Wittenberg; Kurt-Mothes-Straße 3 Halle (Saale) 06120 Germany
| | - Eyleen Heidrich
- Institute of Microbiology; Leibniz Universität Hannover; Herrenhäuser Str. 2 Hannover 30419 Germany
| | - Denise Mehner
- Institute of Microbiology; Leibniz Universität Hannover; Herrenhäuser Str. 2 Hannover 30419 Germany
| | - Hauke Lilie
- Institute of Biochemistry and Biotechnology; Martin-Luther University Halle-Wittenberg; Kurt-Mothes-Straße 3 Halle (Saale) 06120 Germany
| | - Christoph Parthier
- Institute of Biochemistry and Biotechnology; Martin-Luther University Halle-Wittenberg; Kurt-Mothes-Straße 3 Halle (Saale) 06120 Germany
| | - H. Jelger Risselada
- Max Planck Institute for Biophysical Chemistry; Am Fassberg 11 Göttingen 37077 Germany
| | - Helmut Grubmüller
- Max Planck Institute for Biophysical Chemistry; Am Fassberg 11 Göttingen 37077 Germany
| | - Milton T. Stubbs
- Institute of Biochemistry and Biotechnology; Martin-Luther University Halle-Wittenberg; Kurt-Mothes-Straße 3 Halle (Saale) 06120 Germany
| | - Thomas Brüser
- Institute of Microbiology; Leibniz Universität Hannover; Herrenhäuser Str. 2 Hannover 30419 Germany
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Membrane Stored Curvature Elastic Stress Modulates Recruitment of Maintenance Proteins PspA and Vipp1. mBio 2015; 6:e01188-15. [PMID: 26330516 PMCID: PMC4556811 DOI: 10.1128/mbio.01188-15] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Phage shock protein A (PspA), which is responsible for maintaining inner membrane integrity under stress in enterobacteria, and vesicle-inducting protein in plastids 1 (Vipp1), which functions for membrane maintenance and thylakoid biogenesis in cyanobacteria and plants, are similar peripheral membrane-binding proteins. Their homologous N-terminal amphipathic helices are required for membrane binding; however, the membrane features recognized and required for expressing their functionalities have remained largely uncharacterized. Rigorously controlled, in vitro methodologies with lipid vesicles and purified proteins were used in this study and provided the first biochemical and biophysical characterizations of membrane binding by PspA and Vipp1. Both proteins are found to sense stored curvature elastic (SCE) stress and anionic lipids within the membrane. PspA has an enhanced sensitivity for SCE stress and a higher affinity for the membrane than Vipp1. These variations in binding may be crucial for some of the proteins’ differing roles in vivo. Assays probing the transcriptional regulatory function of PspA in the presence of vesicles showed that a relief of transcription inhibition occurs in an SCE stress-specific manner. This in vitro recapitulation of membrane stress-dependent transcription control suggests that the Psp response may be mounted in vivo when a cell’s inner membrane experiences increased SCE stress. All cell types maintain the integrity of their membrane systems. One widely distributed membrane stress response system in bacteria is the phage shock protein (Psp) system. The central component, peripheral membrane protein PspA, which mitigates inner membrane stress in bacteria, has a counterpart, Vipp1, which functions for membrane maintenance and thylakoid biogenesis in plants and photosynthetic bacteria. Membrane association of both these proteins is accepted as playing a pivotal role in their functions. Here we show that direct membrane binding by PspA and Vipp1 is driven by two physio-chemical signals, one of which is membrane stress specific. Our work points to alleviation of membrane stored curvature elastic stress by amphipathic helix insertions as an attractive mechanism for membrane maintenance by PspA and Vipp1. Furthermore, the identification of a physical, stress-related membrane signal suggests a unilateral mechanism that promotes both binding of PspA and induction of the Psp response.
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30
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Is the cellular and molecular machinery docile in the stationary phase of Escherichia coli? Biochem Soc Trans 2015; 43:168-71. [DOI: 10.1042/bst20140267] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The bacterial cell envelope retains a highly dense cytoplasm. The properties of the cytoplasm change with the metabolic state of the cell, the logarithmic phase (log) being highly active and the stationary phase metabolically much slower. Under the differing growth phases, many different types of stress mechanisms are activated in order to maintain cellular integrity. One such response in enterobacteria is the phage shock protein (Psp) response that enables adaptation to the inner membrane (IM) stress. The Psp system consists of a transcriptional activator PspF, negative regulator PspA, signal sensors PspBC, with PspA and PspG acting as effectors. The single molecule imaging of the PspF showed the existence of dynamic communication between the nucleoid-bound states of PspF and membrane via negative regulator PspA and PspBC sensors. The movement of proteins in the cytoplasm of bacterial cells is often by passive diffusion. It is plausible that the dynamics of the biomolecules differs with the state of the cytoplasm depending on the growth phase. Therefore, the Psp response proteins might encounter the densely packed glass-like properties of the cytoplasm in the stationary phase, which can influence their cellular dynamics and function. By comparing the properties of the log and stationary phases, we find that the dynamics of PspF are influenced by the growth phase and may be controlled by the changes in the cytoplasmic fluidity.
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Mancini S, Imlay JA. The induction of two biosynthetic enzymes helps Escherichia coli sustain heme synthesis and activate catalase during hydrogen peroxide stress. Mol Microbiol 2015; 96:744-63. [PMID: 25664592 DOI: 10.1111/mmi.12967] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2015] [Indexed: 11/29/2022]
Abstract
Hydrogen peroxide pervades many natural environments, including the phagosomes that mediate cell-based immunity. Transcriptomic analysis showed that during protracted low-grade H(2)O(2) stress, Escherichia coli responds by activating both the OxyR defensive regulon and the Fur iron-starvation response. OxyR induced synthesis of two members of the nine-step heme biosynthetic pathway: ferrochelatase (HemH) and an isozyme of coproporphyrinogen III oxidase (HemF). Mutations that blocked either adaptation caused the accumulation of porphyrin intermediates, inadequate activation of heme enzymes, low catalase activity, defective clearance of H(2)O(2) and a failure to grow. Genetic analysis indicated that HemH induction is needed to compensate for iron sequestration by the mini-ferritin Dps. Dps activity protects DNA and proteins by limiting Fenton chemistry, but it interferes with the ability of HemH to acquire the iron that it needs to complete heme synthesis. HemF is a manganoprotein that displaces HemN, an iron-sulfur enzyme whose synthesis and/or stability is apparently problematic during H(2)O(2) stress. Thus, the primary responses to H(2)O(2), including the sequestration of iron, require compensatory adjustments in the mechanisms of iron-cofactor synthesis. The results support the growing evidence that oxidative stress is primarily an iron pathology.
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Affiliation(s)
- Stefano Mancini
- Department of Microbiology, University of Illinois, Urbana, IL, 61801, USA
| | - James A Imlay
- Department of Microbiology, University of Illinois, Urbana, IL, 61801, USA
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Zhang L, Sakamoto W. Possible function of VIPP1 in maintaining chloroplast membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:831-7. [PMID: 25725437 DOI: 10.1016/j.bbabio.2015.02.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 02/09/2015] [Accepted: 02/14/2015] [Indexed: 01/03/2023]
Abstract
A protein designated as VIPP1 is found widely in organisms performing oxygenic photosynthesis, but its precise role in chloroplasts has remained somewhat mysterious. Based on its structural similarity, it presumably has evolved from bacterial Phage shock protein A (PspA) with a C-terminal extension of approximately 40 amino acids. Both VIPP1 and PspA are membrane-associated despite the lack of transmembrane helices. They form an extremely large homo-complex that consists of an oligomeric ring unit. Although PspA is known to respond to membrane stress and although it acts in maintaining proton motive force through membrane repair, the multiple function of VIPP1, such as vesicle budding from inner envelope to deliver lipids to thylakoids, maintenance of photosynthetic complexes in thylakoid membranes, biogenesis of Photosystem I, and protective role of inner envelope against osmotic stress, has been proposed. Whatever its precise function in chloroplasts, it is an important protein because depletion of VIPP1 in mutants severely affects photoautotrophic growth. Recent reports of the relevant literature describe that VIPP1 becomes highly mobile when chloroplasts receive hypotonic stress, and that VIPP1 is tightly bound to lipids, which implies a crucial role of VIPP1 in membrane repair through lipid transfer. This review presents a summary of our current knowledge related to VIPP1, particularly addressing the dynamic behavior of complexes against stress and its property of lipid binding. Those data altogether suggest that VIPP1 acts a priori in chloroplast membrane maintenance through its activity to transfer lipids rather than in thylakoid formation through vesicles. This article is part of a Special Issue titled: Chloroplast Biogenesis.
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Affiliation(s)
- Lingang Zhang
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan
| | - Wataru Sakamoto
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan.
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Jovanovic G, Mehta P, Ying L, Buck M. Anionic lipids and the cytoskeletal proteins MreB and RodZ define the spatio-temporal distribution and function of membrane stress controller PspA in Escherichia coli. Microbiology (Reading) 2014; 160:2374-2386. [DOI: 10.1099/mic.0.078527-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
All cell types must maintain the integrity of their membranes. The conserved bacterial membrane-associated protein PspA is a major effector acting upon extracytoplasmic stress and is implicated in protection of the inner membrane of pathogens, formation of biofilms and multi-drug-resistant persister cells. PspA and its homologues in Gram-positive bacteria and archaea protect the cell envelope whilst also supporting thylakoid biogenesis in cyanobacteria and higher plants. In enterobacteria, PspA is a dual function protein negatively regulating the Psp system in the absence of stress and acting as an effector of membrane integrity upon stress. We show that in Escherichia coli the low-order oligomeric PspA regulatory complex associates with cardiolipin-rich, curved polar inner membrane regions. There, cardiolipin and the flotillin 1 homologue YqiK support the PspBC sensors in transducing a membrane stress signal to the PspA-PspF inhibitory complex. After stress perception, PspA high-order oligomeric effector complexes initially assemble in polar membrane regions. Subsequently, the discrete spatial distribution and dynamics of PspA effector(s) in lateral membrane regions depend on the actin homologue MreB and the peptidoglycan machinery protein RodZ. The consequences of loss of cytoplasmic membrane anionic lipids, MreB, RodZ and/or YqiK suggest that the mode of action of the PspA effector is closely associated with cell envelope organization.
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Affiliation(s)
- Goran Jovanovic
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Parul Mehta
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Liming Ying
- National Heart and Lung Institute, Imperial College London, London SW7 2AZ, UK
| | - Martin Buck
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
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34
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Yao Z, Carballido-López R. Fluorescence Imaging for Bacterial Cell Biology: From Localization to Dynamics, From Ensembles to Single Molecules. Annu Rev Microbiol 2014; 68:459-76. [DOI: 10.1146/annurev-micro-091213-113034] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Zhizhong Yao
- INRA, UMR1319 Micalis, F-78350 Jouy-en-Josas, France;
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35
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Wallrodt I, Jelsbak L, Thomsen LE, Brix L, Lemire S, Gautier L, Nielsen DS, Jovanovic G, Buck M, Olsen JE. Removal of the phage-shock protein PspB causes reduction of virulence in Salmonella enterica serovar Typhimurium independently of NRAMP1. J Med Microbiol 2014; 63:788-795. [DOI: 10.1099/jmm.0.072223-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The phage-shock protein (Psp) system is believed to manage membrane stress in all Enterobacteriaceae and has recently emerged as being important for virulence in several pathogenic species of this phylum. The core of the Psp system consists of the pspA–D operon and the distantly located pspG gene. In Salmonella enterica serovar Typhimurium (S. Typhimurium), it has recently been reported that PspA is essential for systemic infection of mice, but only in NRAMP1+ mice, signifying that attenuation is related to coping with divalent cation starvation in the intracellular environment. In the present study, we investigated the contribution of individual psp genes to virulence of S. Typhimurium. Interestingly, deletion of the whole pspA–D set of genes caused attenuation in both NRAMP1+ and NRAMP1− mice, indicating that one or more of the psp genes contribute to virulence independently of NRAMP1 expression in the host. Investigations of single gene mutants showed that knock out of pspB reduced virulence in both types of mice, while deletion of pspA only caused attenuation in NRAMP1+ mice, and deletion of pspD had a minor effect in NRAMP1− mice, while deletions of either pspC or pspG did not affect virulence. Experiments addressed at elucidating the role of PspB in virulence revealed that PspB is dispensable for uptake to and intracellular replication in cultured macrophages and resistance to complement-induced killing. Furthermore, the Psp system of S. Typhimurium was dispensable during pIV-induced secretin stress. In conclusion, our results demonstrate that removal of PspB reduces virulence in S. Typhimurium independently of host NRAMP1 expression, demonstrating that PspB has roles in intra-host survival distinct from the reported contributions of PspA.
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Affiliation(s)
- Inke Wallrodt
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Lotte Jelsbak
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Line E. Thomsen
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Lena Brix
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Sébastien Lemire
- Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | - Laurent Gautier
- Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | - Dennis S. Nielsen
- Department of Food Science, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Goran Jovanovic
- Division of Cell and Molecular Biology, Imperial College London, South Kensington, London, UK
| | - Martin Buck
- Division of Cell and Molecular Biology, Imperial College London, South Kensington, London, UK
| | - John E. Olsen
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
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