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Morrison JJ, Madden EK, Banas DA, DiBiasio EC, Hansen M, Krogfelt KA, Rowley DC, Cohen PS, Camberg JL. Metabolic flux regulates growth transitions and antibiotic tolerance in uropathogenic Escherichia coli. J Bacteriol 2024; 206:e0016224. [PMID: 38814092 DOI: 10.1128/jb.00162-24] [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: 04/25/2024] [Accepted: 05/06/2024] [Indexed: 05/31/2024] Open
Abstract
Reducing growth and limiting metabolism are strategies that allow bacteria to survive exposure to environmental stress and antibiotics. During infection, uropathogenic Escherichia coli (UPEC) may enter a quiescent state that enables them to reemerge after the completion of successful antibiotic treatment. Many clinical isolates, including the well-characterized UPEC strain CFT073, also enter a metabolite-dependent, quiescent state in vitro that is reversible with cues, including peptidoglycan-derived peptides and amino acids. Here, we show that quiescent UPEC is antibiotic tolerant and demonstrate that metabolic flux in the tricarboxylic acid (TCA) cycle regulates the UPEC quiescent state via succinyl-CoA. We also demonstrate that the transcriptional regulator complex integration host factor and the FtsZ-interacting protein ZapE, which is important for E. coli division during stress, are essential for UPEC to enter the quiescent state. Notably, in addition to engaging FtsZ and late-stage cell division proteins, ZapE also interacts directly with TCA cycle enzymes in bacterial two-hybrid assays. We report direct interactions between the succinate dehydrogenase complex subunit SdhC, the late-stage cell division protein FtsN, and ZapE. These interactions may enable communication between oxidative metabolism and the cell division machinery in UPEC. Moreover, these interactions are conserved in an E. coli K-12 strain. This work suggests that there is coordination among the two fundamental and essential pathways that regulate overall growth, quiescence, and antibiotic susceptibility. IMPORTANCE Uropathogenic Escherichia coli (UPEC) are the leading cause of urinary tract infections (UTIs). Upon invasion into bladder epithelial cells, UPEC establish quiescent intracellular reservoirs that may lead to antibiotic tolerance and recurrent UTIs. Here, we demonstrate using an in vitro system that quiescent UPEC cells are tolerant to ampicillin and have decreased metabolism characterized by succinyl-CoA limitation. We identify the global regulator integration host factor complex and the cell division protein ZapE as critical modifiers of quiescence and antibiotic tolerance. Finally, we show that ZapE interacts with components of both the cell division machinery and the tricarboxylic acid cycle, and this interaction is conserved in non-pathogenic E. coli, establishing a novel link between cell division and metabolism.
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Affiliation(s)
- Josiah J Morrison
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Ellen K Madden
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Daniel A Banas
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Eric C DiBiasio
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Mads Hansen
- Department of Natural Science and Environment, Centre for Mathematical Modeling - Human Health and Disease, University of Roskilde, Roskilde, Denmark
| | - Karen A Krogfelt
- Department of Natural Science and Environment, Centre for Mathematical Modeling - Human Health and Disease, University of Roskilde, Roskilde, Denmark
| | - David C Rowley
- Department of Biomedical and Pharmaceutical Sciences, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Paul S Cohen
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Jodi L Camberg
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
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2
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Zhao S, Makarova KS, Zheng W, Zhan L, Wan Q, Liu Y, Gong H, Krupovic M, Lutkenhaus J, Chen X, Koonin EV, Du S. Widespread photosynthesis reaction centre barrel proteins are necessary for haloarchaeal cell division. Nat Microbiol 2024; 9:712-726. [PMID: 38443574 DOI: 10.1038/s41564-024-01615-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 01/19/2024] [Indexed: 03/07/2024]
Abstract
Cell division is fundamental to all cellular life. Most archaea depend on either the prokaryotic tubulin homologue FtsZ or the endosomal sorting complex required for transport for division but neither system has been robustly characterized. Here, we show that three of the four photosynthesis reaction centre barrel domain proteins of Haloferax volcanii (renamed cell division proteins B1/2/3 (CdpB1/2/3)) play important roles in cell division. CdpB1 interacts directly with the FtsZ membrane anchor SepF and is essential for cell division, whereas deletion of cdpB2 and cdpB3 causes a major and a minor division defect, respectively. Orthologues of CdpB proteins are also involved in cell division in other haloarchaea, indicating a conserved function of these proteins. Phylogenetic analysis shows that photosynthetic reaction centre barrel proteins are widely distributed among archaea and appear to be central to cell division in most if not all archaea.
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Affiliation(s)
- Shan Zhao
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Wenchao Zheng
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Le Zhan
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Qianqian Wan
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yafei Liu
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Han Gong
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, Paris, France
| | - Joe Lutkenhaus
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Xiangdong Chen
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA.
| | - Shishen Du
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China.
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3
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Morrison JJ, Camberg JL. Building the Bacterial Divisome at the Septum. Subcell Biochem 2024; 104:49-71. [PMID: 38963483 DOI: 10.1007/978-3-031-58843-3_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
Across living organisms, division is necessary for cell survival and passing heritable information to the next generation. For this reason, cell division is highly conserved among eukaryotes and prokaryotes. Among the most highly conserved cell division proteins in eukaryotes are tubulin and actin. Tubulin polymerizes to form microtubules, which assemble into cytoskeletal structures in eukaryotes, such as the mitotic spindle that pulls chromatids apart during mitosis. Actin polymerizes to form a morphological framework for the eukaryotic cell, or cytoskeleton, that undergoes reorganization during mitosis. In prokaryotes, two of the most highly conserved cell division proteins are the tubulin homolog FtsZ and the actin homolog FtsA. In this chapter, the functions of the essential bacterial cell division proteins FtsZ and FtsA and their roles in assembly of the divisome at the septum, the site of cell division, will be discussed. In most bacteria, including Escherichia coli, the tubulin homolog FtsZ polymerizes at midcell, and this step is crucial for recruitment of many other proteins to the division site. For this reason, both FtsZ abundance and polymerization are tightly regulated by a variety of proteins. The actin-like FtsA protein polymerizes and tethers FtsZ polymers to the cytoplasmic membrane. Additionally, FtsA interacts with later stage cell division proteins, which are essential for division and for building the new cell wall at the septum. Recent studies have investigated how actin-like polymerization of FtsA on the lipid membrane may impact division, and we will discuss this and other ways that division in bacteria is regulated through FtsZ and FtsA.
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Affiliation(s)
- Josiah J Morrison
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, RI, USA
| | - Jodi L Camberg
- Department of Cell and Molecular Biology, The University of Rhode Island, Kingston, RI, USA.
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4
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Savinov A, Swanson S, Keating AE, Li GW. High-throughput computational discovery of inhibitory protein fragments with AlphaFold. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.19.572389. [PMID: 38187731 PMCID: PMC10769210 DOI: 10.1101/2023.12.19.572389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Peptides can bind to specific sites on larger proteins and thereby function as inhibitors and regulatory elements. Peptide fragments of larger proteins are particularly attractive for achieving these functions due to their inherent potential to form native-like binding interactions. Recently developed experimental approaches allow for high-throughput measurement of protein fragment inhibitory activity in living cells. However, it has thus far not been possible to predict de novo which of the many possible protein fragments bind their protein targets, let alone act as inhibitors. We have developed a computational method, FragFold, that employs AlphaFold to predict protein fragment binding to full-length protein targets in a high-throughput manner. Applying FragFold to thousands of fragments tiling across diverse proteins revealed peaks of predicted binding along each protein sequence. These predictions were compared with experimentally measured peaks of inhibitory activity in E. coli. We establish that our approach is a sensitive predictor of protein fragment function: Evaluating inhibitory fragments derived from known protein-protein interaction interfaces, we found 87% were predicted by FragFold to bind in a native-like mode. Across full protein sequences, 68% of FragFold-predicted binding peaks match experimentally measured inhibitory peaks. This is true even when the underlying inhibitory mechanism is unclear from existing structural data, and we find FragFold is able to predict novel binding modes for inhibitory fragments of unknown structure, explaining previous genetic and biochemical data for these fragments. The success rate of FragFold demonstrates that this computational approach should be broadly applicable for discovering inhibitory protein fragments across proteomes.
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Affiliation(s)
- Andrew Savinov
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sebastian Swanson
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Amy E. Keating
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Koch Center for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Gene-Wei Li
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
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5
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Naha A, Haeusser DP, Margolin W. Anchors: A way for FtsZ filaments to stay membrane bound. Mol Microbiol 2023; 120:525-538. [PMID: 37503768 PMCID: PMC10593102 DOI: 10.1111/mmi.15067] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/10/2023] [Accepted: 04/12/2023] [Indexed: 07/29/2023]
Abstract
Most bacteria use the tubulin homolog FtsZ to organize their cell division. FtsZ polymers initially assemble into mobile complexes that circle around a ring-like structure at the cell midpoint, followed by the recruitment of other proteins that will constrict the cytoplasmic membrane and synthesize septal peptidoglycan to divide the cell. Despite the need for FtsZ polymers to associate with the membrane, FtsZ lacks intrinsic membrane binding ability. Consequently, FtsZ polymers have evolved to interact with the membrane through adaptor proteins that both bind FtsZ and the membrane. Here, we discuss recent progress in understanding the functions of these FtsZ membrane tethers. Some, such as FtsA and SepF, are widely conserved and assemble into varied oligomeric structures bound to the membrane through an amphipathic helix. Other less-conserved proteins, such as EzrA and ZipA, have transmembrane domains, make extended structures, and seem to bind to FtsZ through two separate interactions. This review emphasizes that most FtsZs use multiple membrane tethers with overlapping functions, which not only attach FtsZ polymers to the membrane but also organize them in specific higher-order structures that can optimize cell division activity. We discuss gaps in our knowledge of these concepts and how future studies can address them.
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Affiliation(s)
- Arindam Naha
- Department of Microbiology and Molecular Genetics, UTHealth-Houston, Houston, TX 77030, USA
| | - Daniel P. Haeusser
- Department of Microbiology and Molecular Genetics, UTHealth-Houston, Houston, TX 77030, USA
- Department of Biology, Canisius College, Buffalo, NY 14208, USA
| | - William Margolin
- Department of Microbiology and Molecular Genetics, UTHealth-Houston, Houston, TX 77030, USA
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6
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Myszka K, Tomaś N, Juzwa W, Wolko Ł. Chlorogenic Acid Inhibits Rahnella aquatilis KM25 Growth and Proteolytic Activity in Fish-Based Products. Microorganisms 2023; 11:1367. [PMID: 37374869 DOI: 10.3390/microorganisms11061367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 05/04/2023] [Accepted: 05/20/2023] [Indexed: 06/29/2023] Open
Abstract
This work verified the antiproliferative and antiproteolytic activities of chlorogenic acid against Rahnella aquatilis KM25, a spoilage organism of raw salmon stored at 4 °C. Chlorogenic acid limited the growth of R. aqatilis KM25 in vitro at a concentration of 2.0 mg/mL. The dead (46%), viable (25%), and injured (20%) cell subpopulations were identified by flow cytometry following treatment of R. aquatilis KM25 with the examined agent. The exposure of R. aquatilis KM25 to chlorogenic acid altered its morphology. Changes in cell dimensions, mostly in length parameters from 0.778 µm to 1.09 µm, were found. The length of untreated cells ranged from 0.958 µm to 1.53 µm. The RT-qPCR experiments revealed changes in the expression of genes responsible for the proliferation and proteolytic activity of cells. Chlorogenic acid caused a significant reduction in the mRNA levels of the ftsZ, ftsA, ftsN, tolB, and M4 genes (-2.5, -1.5, -2.0, -1.5, and -1.5, respectively). In situ experiments confirmed the potential of chlorogenic acid to limit bacterial growth. A similar effect was noted in samples treated with benzoic acid, where the growth inhibition of R. aquatilis KM25 was 85-95%. Reduction of microbial R. aquatilis KM25 proliferation significantly limited total volatile base nitrogen (TVB-N) and trimethylamine (TMA-N) formation during storage, extending the shelf life of model products. The TVB-N and TMA-N parameters did not exceed the upper levels of the maximum permissible limit of acceptability. In this work, the TVB-N and TMA-N parameters were 10-25 mg/100 g and 2.5-20.5 mg/100 g, respectively; for samples with benzoic acid-supplemented marinades, the parameters TVB-N and TMA-N were 7.5-25.0 mg/100 g and 2.0-20.0 mg/100 g, respectively. Based on the results of this work, it can be concluded that chlorogenic acid can increase the safety, shelf life, and quality of fishery products.
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Affiliation(s)
- Kamila Myszka
- Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48, 60-627 Poznan, Poland
| | - Natalia Tomaś
- Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48, 60-627 Poznan, Poland
| | - Wojciech Juzwa
- Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, Wojska Polskiego 48, 60-627 Poznan, Poland
| | - Łukasz Wolko
- Department of Biochemistry and Biotechnology, Poznan University of Life Sciences, Dojazd 11, 60-632 Poznan, Poland
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7
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Morrison JJ, Ferreira CN, Siler EM, Nelson K, Trebino CE, Piraino B, Camberg JL. Nucleotide-dependent activities of FtsA regulate the early establishment of a functional divisome during the Escherichia coli cell cycle. Front Microbiol 2023; 14:1171376. [PMID: 37250038 PMCID: PMC10213515 DOI: 10.3389/fmicb.2023.1171376] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 04/24/2023] [Indexed: 05/31/2023] Open
Abstract
During cell division in Escherichia coli, the highly conserved tubulin homolog FtsZ polymerizes and assembles into a ring-like structure, called the Z-ring, at the site of septation. For recruitment to the membrane surface, FtsZ polymers directly interact with membrane-associated proteins, predominantly FtsA in E. coli. FtsA shares structural homology with actin and, like actin, hydrolyzes ATP. Yeast actin detects nucleotide occupancy through a sensor region adjacent to the nucleotide binding site and adopts distinct conformations in monomeric and filamentous actin. Bacterial actin homologs also display considerable conformational flexibility across different nucleotide-bound states and polymerize. Here, we show that several amino acid residues proximal to the nucleotide binding site in FtsA are critical for function in vitro and in vivo. Each of these residues are important for ATP hydrolysis, phospholipid (PL) binding, ATP-dependent vesicle remodeling, and recruitment to the divisome in vivo, to varying degrees. Notably, we observed that Ser 84 and Glu 14 are essential for ATP-dependent vesicle remodeling and magnesium-dependent membrane release of FtsA from vesicles in vitro, and these defects likely underlie the loss of function by FtsA(E14R) and FtsA(S84L) in vivo. Finally, we demonstrate that FtsA(A188V), which is associated with temperature-sensitive growth in vivo, is defective for rapid ATP hydrolysis and ATP-dependent remodeling of PL vesicles in vitro. Together, our results show that loss of nucleotide-dependent activities by FtsA, such as ATP hydrolysis, membrane binding and release, and, most importantly, ATP-dependent PL remodeling, lead to failed Z-ring assembly and division defects in cells.
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8
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Zhao S, Makarova KS, Zheng W, Liu Y, Zhan L, Wan Q, Gong H, Krupovic M, Lutkenhaus J, Chen X, Koonin EV, Du S. Widespread PRC barrel proteins play critical roles in archaeal cell division. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.28.534520. [PMID: 37090588 PMCID: PMC10120694 DOI: 10.1101/2023.03.28.534520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Cell division is fundamental to all cellular life. Most of the archaea employ one of two alternative division machineries, one centered around the prokaryotic tubulin homolog FtsZ and the other around the endosomal sorting complex required for transport (ESCRT). However, neither of these mechanisms has been thoroughly characterized in archaea. Here, we show that three of the four PRC (Photosynthetic Reaction Center) barrel domain proteins of Haloferax volcanii (renamed Cell division proteins B1/2/3 (CdpB1/2/3)), play important roles in division. CdpB1 interacts directly with the FtsZ membrane anchor SepF and is essential for division, whereas deletion of cdpB2 and cdpB3 causes a major and a minor division defect, respectively. Orthologs of CdpB proteins are also involved in cell division in other haloarchaea. Phylogenetic analysis shows that PRC barrel proteins are widely distributed among archaea, including the highly conserved CdvA protein of the crenarchaeal ESCRT-based division system. Thus, diverse PRC barrel proteins appear to be central to cell division in most if not all archaea. Further study of these proteins is expected to elucidate the division mechanisms in archaea and their evolution.
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Affiliation(s)
- Shan Zhao
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, Hubei, China
| | - Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD, USA
| | - Wenchao Zheng
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, Hubei, China
| | - Yafei Liu
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, Hubei, China
| | - Le Zhan
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, Hubei, China
| | - Qianqian Wan
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, Hubei, China
| | - Han Gong
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, Hubei, China
| | - Mart Krupovic
- Institut Pasteur, Unité Biologie Moléculaire du Gène chez les Extrêmophiles, Paris, France
| | - Joe Lutkenhaus
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Xiangdong Chen
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, Hubei, China
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD, USA
| | - Shishen Du
- Department of Microbiology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, Hubei, China
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9
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RefZ and Noc Act Synthetically to Prevent Aberrant Divisions during Bacillus subtilis Sporulation. J Bacteriol 2022; 204:e0002322. [PMID: 35506695 DOI: 10.1128/jb.00023-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During sporulation, Bacillus subtilis undergoes an atypical cell division that requires overriding mechanisms that protect chromosomes from damage and ensure inheritance by daughter cells. Instead of assembling between segregated chromosomes at midcell, the FtsZ-ring coalesces polarly, directing division over one chromosome. The DNA-binding protein RefZ facilitates the timely assembly of polar Z-rings and partially defines the region of chromosome initially captured in the forespore. RefZ binds to motifs (RBMs) located proximal to the origin of replication (oriC). Although refZ and the RBMs are conserved across the Bacillus genus, a refZ deletion mutant sporulates with wild-type efficiency, so the functional significance of RefZ during sporulation remains unclear. To further investigate RefZ function, we performed a candidate-based screen for synthetic sporulation defects by combining ΔrefZ with deletions of genes previously implicated in FtsZ regulation and/or chromosome capture. Combining ΔrefZ with deletions of ezrA, sepF, parA, or minD did not detectably affect sporulation. In contrast, a ΔrefZ Δnoc mutant exhibited a sporulation defect, revealing a genetic interaction between RefZ and Noc. Using reporters of sporulation progression, we determined the ΔrefZ Δnoc mutant exhibited sporulation delays after Spo0A activation but prior to late sporulation, with a subset of cells failing to divide polarly or activate the first forespore-specific sigma factor, SigF. The ΔrefZ Δnoc mutant also exhibited extensive dysregulation of cell division, producing cells with extra, misplaced, or otherwise aberrant septa. Our results reveal a previously unknown epistatic relationship that suggests refZ and noc contribute synthetically to regulating cell division and supporting spore development. IMPORTANCE The DNA-binding protein RefZ and its binding sites (RBMs) are conserved in sequence and location on the chromosome across the Bacillus genus and contribute to the timing of polar FtsZ-ring assembly during sporulation. Only a small number of noncoding and nonregulatory DNA motifs are known to be conserved in chromosomal position in bacteria, suggesting there is strong selective pressure for their maintenance; however, a refZ deletion mutant sporulates efficiently, providing no clues as to their functional significance. Here, we find that in the absence of the nucleoid occlusion factor Noc, deletion of refZ results in a sporulation defect characterized by developmental delays and aberrant divisions.
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10
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Attaibi M, den Blaauwen T. An Updated Model of the Divisome: Regulation of the Septal Peptidoglycan Synthesis Machinery by the Divisome. Int J Mol Sci 2022; 23:3537. [PMID: 35408901 PMCID: PMC8998562 DOI: 10.3390/ijms23073537] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/21/2022] [Accepted: 03/22/2022] [Indexed: 02/06/2023] Open
Abstract
The synthesis of a peptidoglycan septum is a fundamental part of bacterial fission and is driven by a multiprotein dynamic complex called the divisome. FtsW and FtsI are essential proteins that synthesize the peptidoglycan septum and are controlled by the regulatory FtsBLQ subcomplex and the activator FtsN. However, their mode of regulation has not yet been uncovered in detail. Understanding this process in detail may enable the development of new compounds to combat the rise in antibiotic resistance. In this review, recent data on the regulation of septal peptidoglycan synthesis is summarized and discussed. Based on structural models and the collected data, multiple putative interactions within FtsWI and with regulators are uncovered. This elaborates on and supports an earlier proposed model that describes active and inactive conformations of the septal peptidoglycan synthesis complex that are stabilized by these interactions. Furthermore, a new model on the spatial organization of the newly synthesized peptidoglycan and the synthesis complex is presented. Overall, the updated model proposes a balance between several allosteric interactions that determine the state of septal peptidoglycan synthesis.
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Affiliation(s)
| | - Tanneke den Blaauwen
- Bacterial Cell Biology and Physiology, Swammerdam Institute for Life Science, University of Amsterdam, 1098 XH Amsterdam, The Netherlands;
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11
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Morrison JJ, Conti J, Camberg JL. Assembly and architecture of Escherichia coli divisome proteins FtsA and FtsZ. J Biol Chem 2022; 298:101663. [PMID: 35104502 PMCID: PMC8897712 DOI: 10.1016/j.jbc.2022.101663] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 11/30/2022] Open
Abstract
During Escherichia coli cell division, an intracellular complex of cell division proteins known as the Z-ring assembles at midcell during early division and serves as the site of constriction. While the predominant protein in the Z-ring is the widely conserved tubulin homolog FtsZ, the actin homolog FtsA tethers the Z-ring scaffold to the cytoplasmic membrane by binding to FtsZ. While FtsZ is known to function as a dynamic, polymerized GTPase, the assembly state of its partner, FtsA, and the role of ATP are still unclear. We report that a substitution mutation in the FtsA ATP-binding site impairs ATP hydrolysis, phospholipid vesicle remodeling in vitro, and Z-ring assembly in vivo. We demonstrate by transmission electron microscopy and Förster Resonance Energy Transfer that a truncated FtsA variant, FtsA(ΔMTS) lacking a C-terminal membrane targeting sequence, self assembles into ATP-dependent filaments. These filaments coassemble with FtsZ polymers but are destabilized by unassembled FtsZ. These findings suggest a model wherein ATP binding drives FtsA polymerization and membrane remodeling at the lipid surface, and FtsA polymerization is coregulated with FtsZ polymerization. We conclude that the coordinated assembly of FtsZ and FtsA polymers may serve as a key checkpoint in division that triggers cell wall synthesis and division progression.
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Affiliation(s)
- Josiah J Morrison
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Joseph Conti
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA
| | - Jodi L Camberg
- Department of Cell & Molecular Biology, The University of Rhode Island, Kingston, Rhode Island, USA.
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12
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FtsA acts through FtsW to promote cell wall synthesis during cell division in Escherichia coli. Proc Natl Acad Sci U S A 2021; 118:2107210118. [PMID: 34453005 DOI: 10.1073/pnas.2107210118] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In Escherichia coli, FtsQLB is required to recruit the essential septal peptidoglycan (sPG) synthase FtsWI to FtsA, which tethers FtsZ filaments to the membrane. The arrival of FtsN switches FtsQLB in the periplasm and FtsA in the cytoplasm from a recruitment role to active forms that synergize to activate FtsWI. Genetic evidence indicates that the active form of FtsQLB has an altered conformation with an exposed domain of FtsL that acts on FtsI to activate FtsW. However, how FtsA contributes to the activation of FtsW is not clear, as it could promote the conformational change in FtsQLB or act directly on FtsW. Here, we show that the overexpression of an activated FtsA (FtsA*) bypasses FtsQ, indicating it can compensate for FtsQ's recruitment function. Consistent with this, FtsA* also rescued FtsL and FtsB mutants deficient in FtsW recruitment. FtsA* also rescued an FtsL mutant unable to deliver the periplasmic signal from FtsN, consistent with FtsA* acting on FtsW. In support of this, an FtsW mutant was isolated that was rescued by an activated FtsQLB but not by FtsA*, indicating it was specifically defective in activation by FtsA. Our results suggest that in response to FtsN, the active form of FtsA acts on FtsW in the cytoplasm and synergizes with the active form of FtsQLB acting on FtsI in the periplasm to activate FtsWI to carry out sPG synthesis.
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Nag D, Dastidar DG, Chakrabarti G. Natural flavonoid morin showed anti-bacterial activity against Vibrio cholera after binding with cell division protein FtsA near ATP binding site. Biochim Biophys Acta Gen Subj 2021; 1865:129931. [PMID: 34023444 DOI: 10.1016/j.bbagen.2021.129931] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 05/17/2021] [Accepted: 05/17/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Increasing antibiotic-resistance in bacterial strains has boosted the need to find new targets for drug delivery. FtsA, a major bacterial divisome protein can be a potent novel drug-target. METHODS AND RESULTS This study finds, morin (3,5,7,2',4'-pentahydroxyflavone), a bio-available flavonoid, had anti-bacterial activities against Vibrio cholerae, IC50 (50 μM) and MIC (150 μM). Morin (2 mM) kills ~20% of human lung fibroblast (WI38) and human intestinal epithelial (HIEC-6) cells in 24 h in-vitro. Fluorescence studies showed morin binds to VcFtsA (FtsA of V. cholerae) with a Kd of 4.68 ± 0.4 μM, inhibiting the protein's polymerization by 72 ± 7% at 25 μM concentration. Morin also affected VcFtsA's ATPase activity, recording ~80% reduction at 20 μM concentration. The in-silico binding study indicated binding sites of morin and ATP on VcFtsA had overlapping amino acids. Mant-ATP, a fluorescent ATP-derivative, showed increased fluorescence on binding to VcFtsA in absence of morin, but in its presence, Mant-ATP fluorescence decreased. VcFtsA-S40A mutant protein did not bind to morin. CONCLUSIONS VcFtsA-morin interaction inhibits the polymerization of the protein by affecting its ATPase activity. The destabilized VcFtsA assembly in-turn affected the cell division in V. cholerae, yielding an elongated morphology. GENERAL SIGNIFICANCE Collectively, these findings explore the anti-bacterial effect of morin on V. cholerae cells targeting VcFtsA, encouraging it to become a potent anti-bacterial agent. Low cytotoxicity of morin against human cells (host) is therapeutically advantageous. This study will also help in synthesizing novel derivatives that can target VcFtsA more efficiently.
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Affiliation(s)
- Debasish Nag
- Department of Biotechnology And Dr. B. C. Guha Centre for Genetic Engineering And Biotechnology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, WB 700 019, India
| | - Debabrata Ghosh Dastidar
- Department of Biotechnology And Dr. B. C. Guha Centre for Genetic Engineering And Biotechnology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, WB 700 019, India; Guru Nanak Institute of Pharmaceutical Science & Technology, 157/F Nilgunj Road, Panihati, Kolkata 700114, West Bengal, India
| | - Gopal Chakrabarti
- Department of Biotechnology And Dr. B. C. Guha Centre for Genetic Engineering And Biotechnology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, WB 700 019, India.
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14
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FtsZ: The Force Awakens. J Indian Inst Sci 2021. [DOI: 10.1007/s41745-020-00215-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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15
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Abstract
How microbial metabolism is translated into cellular reproduction under energy-limited settings below the seafloor over long timescales is poorly understood. Here, we show that microbial abundance increases an order of magnitude over a 5 million-year-long sequence in anoxic subseafloor clay of the abyssal North Atlantic Ocean. This increase in biomass correlated with an increased number of transcribed protein-encoding genes that included those involved in cytokinesis, demonstrating that active microbial reproduction outpaces cell death in these ancient sediments. Metagenomes, metatranscriptomes, and 16S rRNA gene sequencing all show that the actively reproducing community was dominated by the candidate phylum "Candidatus Atribacteria," which exhibited patterns of gene expression consistent with fermentative, and potentially acetogenic, metabolism. "Ca. Atribacteria" dominated throughout the 8 million-year-old cored sequence, despite the detection limit for gene expression being reached in 5 million-year-old sediments. The subseafloor reproducing "Ca. Atribacteria" also expressed genes encoding a bacterial microcompartment that has potential to assist in secondary fermentation by recycling aldehydes and, thereby, harness additional power to reduce ferredoxin and NAD+ Expression of genes encoding the Rnf complex for generation of chemiosmotic ATP synthesis were also detected from the subseafloor "Ca Atribacteria," as well as the Wood-Ljungdahl pathway that could potentially have an anabolic or catabolic function. The correlation of this metabolism with cytokinesis gene expression and a net increase in biomass over the million-year-old sampled interval indicates that the "Ca Atribacteria" can perform the necessary catabolic and anabolic functions necessary for cellular reproduction, even under energy limitation in millions-of-years-old anoxic sediments.IMPORTANCE The deep subseafloor sedimentary biosphere is one of the largest ecosystems on Earth, where microbes subsist under energy-limited conditions over long timescales. It remains poorly understood how mechanisms of microbial metabolism promote increased fitness in these settings. We discovered that the candidate bacterial phylum "Candidatus Atribacteria" dominated a deep-sea subseafloor ecosystem, where it exhibited increased transcription of genes associated with acetogenic fermentation and reproduction in million-year-old sediment. We attribute its improved fitness after burial in the seabed to its capabilities to derive energy from increasingly oxidized metabolites via a bacterial microcompartment and utilize a potentially reversible Wood-Ljungdahl pathway to help meet anabolic and catabolic requirements for growth. Our findings show that "Ca Atribacteria" can perform all the necessary catabolic and anabolic functions necessary for cellular reproduction, even under energy limitation in anoxic sediments that are millions of years old.
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Silber N, Matos de Opitz CL, Mayer C, Sass P. Cell division protein FtsZ: from structure and mechanism to antibiotic target. Future Microbiol 2020; 15:801-831. [DOI: 10.2217/fmb-2019-0348] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Antimicrobial resistance to virtually all clinically applied antibiotic classes severely limits the available options to treat bacterial infections. Hence, there is an urgent need to develop and evaluate new antibiotics and targets with resistance-breaking properties. Bacterial cell division has emerged as a new antibiotic target pathway to counteract multidrug-resistant pathogens. New approaches in antibiotic discovery and bacterial cell biology helped to identify compounds that either directly interact with the major cell division protein FtsZ, thereby perturbing the function and dynamics of the cell division machinery, or affect the structural integrity of FtsZ by inducing its degradation. The impressive antimicrobial activities and resistance-breaking properties of certain compounds validate the inhibition of bacterial cell division as a promising strategy for antibiotic intervention.
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Affiliation(s)
- Nadine Silber
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology & Infection Medicine, University of Tübingen, Auf der Morgenstelle 28, Tübingen 72076, Germany
| | - Cruz L Matos de Opitz
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology & Infection Medicine, University of Tübingen, Auf der Morgenstelle 28, Tübingen 72076, Germany
| | - Christian Mayer
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology & Infection Medicine, University of Tübingen, Auf der Morgenstelle 28, Tübingen 72076, Germany
| | - Peter Sass
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology & Infection Medicine, University of Tübingen, Auf der Morgenstelle 28, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), partner site Tübingen, Tübingen 72076, Germany
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17
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Abstract
The FtsZ protein is a highly conserved bacterial tubulin homolog. In vivo, the functional form of FtsZ is the polymeric, ring-like structure (Z-ring) assembled at the future division site during cell division. While it is clear that the Z-ring plays an essential role in orchestrating cytokinesis, precisely what its functions are and how these functions are achieved remain elusive. In this article, we review what we have learned during the past decade about the Z-ring's structure, function, and dynamics, with a particular focus on insights generated by recent high-resolution imaging and single-molecule analyses. We suggest that the major function of the Z-ring is to govern nascent cell pole morphogenesis by directing the spatiotemporal distribution of septal cell wall remodeling enzymes through the Z-ring's GTP hydrolysis-dependent treadmilling dynamics. In this role, FtsZ functions in cell division as the counterpart of the cell shape-determining actin homolog MreB in cell elongation.
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Affiliation(s)
- Ryan McQuillen
- Department of Biophysics & Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; ,
| | - Jie Xiao
- Department of Biophysics & Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA; ,
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18
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Peptide Linkers within the Essential FtsZ Membrane Tethers ZipA and FtsA Are Nonessential for Cell Division. J Bacteriol 2020; 202:JB.00720-19. [PMID: 31871036 DOI: 10.1128/jb.00720-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 12/19/2019] [Indexed: 12/12/2022] Open
Abstract
Bacteria such as Escherichia coli divide by organizing filaments of FtsZ, a tubulin homolog that assembles into dynamic treadmilling membrane-associated protein filaments at the cell midpoint. FtsA and ZipA proteins are required to tether these filaments to the inner face of the cytoplasmic membrane, and loss of either tether is lethal. ZipA from E. coli and other closely related species harbors a long linker region that connects the essential N-terminal transmembrane domain to the C-terminal globular FtsZ-binding domain, and part of this linker includes a P/Q-rich peptide that is predicted to be intrinsically disordered. We found unexpectedly that several large deletions of the ZipA linker region, including the entire P/Q rich peptide, had no effect on cell division under normal conditions. However, we found that the loss of the P/Q region made cells more resistant to excess levels of FtsA and more sensitive to conditions that displaced FtsA from FtsZ. FtsA also harbors a short ∼20-residue peptide linker that connects the main globular domain with the C-terminal amphipathic helix that is important for membrane binding. In analogy with ZipA, deletion of 11 of the central residues in the FtsA linker had little effect on FtsA function in cell division.IMPORTANCE Escherichia coli cells divide using a cytokinetic ring composed of polymers of the tubulin-like FtsZ. To function properly, these polymers must attach to the inner surface of the cytoplasmic membrane via two essential membrane-associated tethers, FtsA and ZipA. Both FtsA and ZipA contain peptide linkers that connect their membrane-binding domains with their FtsZ-binding domains. Although they are presumed to be crucial for cell division activity, the importance of these linkers has not yet been rigorously tested. Here, we show that large segments of these linkers can be removed with few consequences for cell division, although several subtle defects were uncovered. Our results suggest that ZipA, in particular, can function in cell division without an extended linker.
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19
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Berezuk AM, Roach EJ, Seidel L, Lo RY, Khursigara CM. FtsA G50E mutant suppresses the essential requirement for FtsK during bacterial cell division in Escherichia coli. Can J Microbiol 2020; 66:313-327. [PMID: 31971820 DOI: 10.1139/cjm-2019-0493] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In Escherichia coli, the N-terminal domain of the essential protein FtsK (FtsKN) is proposed to modulate septum formation through the formation of dynamic and essential protein interactions with both the Z-ring and late-stage division machinery. Using genomic mutagenesis, complementation analysis, and in vitro pull-down assays, we aimed to identify protein interaction partners of FtsK essential to its function during division. Here, we identified the cytoplasmic Z-ring membrane anchoring protein FtsA as a direct protein-protein interaction partner of FtsK. Random genomic mutagenesis of an ftsK temperature-sensitive strain of E. coli revealed an FtsA point mutation (G50E) that is able to fully restore normal cell growth and morphology, and further targeted site-directed mutagenesis of FtsA revealed several other point mutations capable of fully suppressing the essential requirement for functional FtsK. Together, this provides insight into a potential novel co-complex formed between these components during division and suggests FtsA may directly impact FtsK function.
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Affiliation(s)
- Alison M Berezuk
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.,Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Elyse J Roach
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.,Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Laura Seidel
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.,Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Reggie Y Lo
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.,Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Cezar M Khursigara
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
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20
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FtsA-FtsZ interaction in Vibrio cholerae causes conformational change of FtsA resulting in inhibition of ATP hydrolysis and polymerization. Int J Biol Macromol 2019; 142:18-32. [PMID: 31790740 DOI: 10.1016/j.ijbiomac.2019.11.217] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 11/23/2022]
Abstract
Proper interaction between the divisome proteins FtsA and FtsZ is important for the bacterial cell division which is not well characterized till date. In this study, the objective was to understand the mechanism of FtsA-FtsZ interaction using full-length recombinant proteins. We cloned, over-expressed, purified and subsequently characterized FtsA of Vibrio cholerae (VcFtsA). We found that VcFtsA polymerization assembly was dependent on Ca2+ ions, which is unique among FtsA proteins reported until now. VcFtsA also showed ATPase activity and its assembly was ATP dependent. Binding parameters of the interaction between the two full-length proteins, VcFtsA, and VcFtsZ determined by fluorescence spectrophotometry yielded a Kd value of around 38 μM. The Kd value of the interaction was 3 μM when VcFtsA was in ATP bound state. We found that VcFtsZ after interacting with VcFtsA causes a change of secondary structure in the later one leading to loss of its ability to hydrolyze ATP, subsequently halting the VcFtsA polymerization. On the other hand, a double-mutant of VcFtsA (VcFtsA-D242E,R300E), that does not bind to VcFtsZ, polymerized in the presence of VcFtsZ. Though FtsA proteins among different organisms show 70-80% homology in their sequences, assembly of VcFtsA showed a difference in its regulatory processes.
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21
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Pichoff S, Du S, Lutkenhaus J. Roles of FtsEX in cell division. Res Microbiol 2019; 170:374-380. [PMID: 31376483 DOI: 10.1016/j.resmic.2019.07.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 07/09/2019] [Accepted: 07/16/2019] [Indexed: 02/04/2023]
Abstract
FtsEX is a member of a small subclass of ABC transporters that uses mechano-transmission to perform work in the periplasm. FtsEX controls periplasmic peptidoglycan (PG) hydrolase activities in many Gram negative and positive organisms to ensure the safe separation of daughter cells during division. In these organisms FtsEX localizes to the Z ring and uses its ATPase activity to regulate its periplasmic effectors. In Escherichia coli, FtsEX also participates in building the divisome and coordinates PG synthesis with PG hydrolysis. This review discusses studies that are beginning to elucidate the mechanisms of FtsEX's various roles in cell division.
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Affiliation(s)
- Sebastien Pichoff
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Shishen Du
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Joe Lutkenhaus
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, 66160, USA.
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22
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Du S, Henke W, Pichoff S, Lutkenhaus J. How FtsEX localizes to the Z ring and interacts with FtsA to regulate cell division. Mol Microbiol 2019; 112:881-895. [PMID: 31175681 DOI: 10.1111/mmi.14324] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2019] [Indexed: 12/14/2022]
Abstract
In Escherichia coli, FtsEX, a member of the ABC transporter superfamily, is involved in regulating the assembly and activation of the divisome to couple cell wall synthesis to cell wall hydrolysis at the septum. Genetic studies indicate FtsEX acts on FtsA to begin the recruitment of the downstream division proteins but blocks septal PG synthesis until a signal is received that divisome assembly is complete. However, the details of how FtsEX localizes to the Z ring and how it interacts with FtsA are not clear. Our results show that recruitment of FtsE and FtsX is codependent and suggest that the FtsEX complex is recruited through FtsE interacting with the conserved tail of FtsZ (CCTP), thus adding FtsEX to a growing list of proteins that interacts with the CCTP of FtsZ. Furthermore, we find that the N-terminus of FtsX is not required for FtsEX localization to the Z ring but is required for its functions in cell division indicating that it interacts with FtsA. Taken together, these results suggest that FtsEX first interacts with FtsZ to localize to the Z ring and then interacts with FtsA to promote divisome assembly and regulate septal PG synthesis.
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Affiliation(s)
- Shishen Du
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Wyatt Henke
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Sebastien Pichoff
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Joe Lutkenhaus
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
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23
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At the Heart of Bacterial Cytokinesis: The Z Ring. Trends Microbiol 2019; 27:781-791. [PMID: 31171437 DOI: 10.1016/j.tim.2019.04.011] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/22/2019] [Accepted: 04/29/2019] [Indexed: 11/20/2022]
Abstract
Bacterial cell division is mediated by the divisome which is organized by the Z ring, a cytoskeletal element formed by the polymerization of the tubulin homologue FtsZ. Despite billions of years of bacterial evolution, the Z ring is nearly universal among bacteria that have a cell wall and divide by binary fission. Recent studies have revealed the mechanism of cooperative assembly of FtsZ and that the Z ring consists of patches of FtsZ filaments tethered to the membrane that treadmill to distribute the septal biosynthetic machinery. Here, we summarize these advances and discuss questions raised by these new findings.
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24
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Roles of the DedD Protein in Escherichia coli Cell Constriction. J Bacteriol 2019; 201:JB.00698-18. [PMID: 30692172 DOI: 10.1128/jb.00698-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 01/20/2019] [Indexed: 02/04/2023] Open
Abstract
Two key tasks of the bacterial septal-ring (SR) machinery during cell constriction are the generation of an inward-growing annulus of septal peptidoglycan (sPG) and the concomitant splitting of its outer edge into two layers of polar PG that will be inherited by the two new cell ends. FtsN is an essential SR protein that helps trigger the active constriction phase in Escherichia coli by inducing a self-enhancing cycle of processes that includes both sPG synthesis and splitting and that we refer to as the sPG loop. DedD is an SR protein that resembles FtsN in several ways. Both are bitopic inner membrane proteins with small N-terminal cytoplasmic parts and larger periplasmic parts that terminate with a SPOR domain. Though absence of DedD normally causes a mild cell-chaining phenotype, the protein is essential for division and survival of cells with limited FtsN activity. Here, we find that a small N-terminal portion of DedD (NDedD; DedD1-54) is required and sufficient to suppress ΔdedD-associated division phenotypes, and we identify residues within its transmembrane domain that are particularly critical to DedD function. Further analyses indicate that DedD and FtsN act in parallel to promote sPG synthesis, possibly by engaging different parts of the FtsBLQ subcomplex to induce a conformation that permits and/or stimulates the activity of sPG synthase complexes composed of FtsW, FtsI (PBP3), and associated proteins. We propose that, like FtsN, DedD promotes cell fission by stimulating sPG synthesis, as well as by providing positive feedback to the sPG loop.IMPORTANCE Cell division (cytokinesis) is a fundamental biological process that is incompletely understood for any organism. Division of bacterial cells relies on a ring-like machinery called the septal ring or divisome that assembles along the circumference of the mother cell at the site where constriction eventually occurs. In the well-studied bacterium Escherichia coli, this machinery contains over 30 distinct proteins. We identify functionally important parts of one of these proteins, DedD, and present evidence supporting a role for DedD in helping to induce and/or sustain a self-enhancing cycle of processes that are executed by fellow septal-ring proteins and that drive the active constriction phase of the cell division cycle.
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Howell M, Aliashkevich A, Sundararajan K, Daniel JJ, Lariviere PJ, Goley ED, Cava F, Brown PJB. Agrobacterium tumefaciens divisome proteins regulate the transition from polar growth to cell division. Mol Microbiol 2019; 111:1074-1092. [PMID: 30693575 DOI: 10.1111/mmi.14212] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/23/2019] [Indexed: 01/06/2023]
Abstract
The mechanisms that restrict peptidoglycan biosynthesis to the pole during elongation and re-direct peptidoglycan biosynthesis to mid-cell during cell division in polar-growing Alphaproteobacteria are largely unknown. Here, we explore the role of early division proteins of Agrobacterium tumefaciens including three FtsZ homologs, FtsA and FtsW in the transition from polar growth to mid-cell growth and ultimately cell division. Although two of the three FtsZ homologs localize to mid-cell, exhibit GTPase activity and form co-polymers, only one, FtsZAT , is required for cell division. We find that FtsZAT is required not only for constriction and cell separation, but also for initiation of peptidoglycan synthesis at mid-cell and cessation of polar peptidoglycan biosynthesis. Depletion of FtsZAT in A. tumefaciens causes a striking phenotype: cells are extensively branched and accumulate growth active poles through tip splitting events. When cell division is blocked at a later stage by depletion of FtsA or FtsW, polar growth is terminated and ectopic growth poles emerge from mid-cell. Overall, this work suggests that A. tumefaciens FtsZ makes distinct contributions to the regulation of polar growth and cell division.
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Affiliation(s)
- Matthew Howell
- Division of Biological Sciences, University of Missouri, Columbia, MO, 65203, USA
| | - Alena Aliashkevich
- Department of Molecular Biology, Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Kousik Sundararajan
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Jeremy J Daniel
- Division of Biological Sciences, University of Missouri, Columbia, MO, 65203, USA
| | - Patrick J Lariviere
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Erin D Goley
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Felipe Cava
- Department of Molecular Biology, Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Pamela J B Brown
- Division of Biological Sciences, University of Missouri, Columbia, MO, 65203, USA
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Reduction in adaptor amounts establishes degradation hierarchy among protease substrates. Proc Natl Acad Sci U S A 2018; 115:E4483-E4492. [PMID: 29686082 DOI: 10.1073/pnas.1722246115] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
ATP-dependent proteases control critical cellular processes, including development, physiology, and virulence. A given protease may recognize a substrate directly via an unfoldase domain or subunit or indirectly via an adaptor that delivers the substrate to the unfoldase. We now report that cells achieve differential stability among substrates of a given protease by modulating adaptor amounts. We establish that the regulatory protein PhoP represses transcription of the gene specifying the ClpAP protease adaptor ClpS when the bacteria Salmonella enterica and Escherichia coli experience low cytoplasmic Mg2+ The resulting decrease in ClpS amounts diminishes proteolysis of several ClpSAP-dependent substrates, including the putrescine aminotransferase Oat, which heightens the formation of antibiotic persisters, and the transcriptional regulators UvrY and PhoP, which alter the expression of genes controlled by these proteins. By contrast, the decrease in ClpS amounts did not impact the abundance of the ClpSAP substrate FtsA, reflecting that FtsA binds to ClpS more tightly than to UvrY and PhoP. Our findings show how physiological conditions that reduce adaptor amounts modify the abundance of selected substrates of a given protease.
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27
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Misra HS, Maurya GK, Chaudhary R, Misra CS. Interdependence of bacterial cell division and genome segregation and its potential in drug development. Microbiol Res 2018; 208:12-24. [DOI: 10.1016/j.micres.2017.12.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 12/05/2017] [Accepted: 12/31/2017] [Indexed: 11/28/2022]
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28
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Conti J, Viola MG, Camberg JL. FtsA reshapes membrane architecture and remodels the Z-ring in Escherichia coli. Mol Microbiol 2018; 107:558-576. [PMID: 29280220 DOI: 10.1111/mmi.13902] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 12/14/2017] [Accepted: 12/17/2017] [Indexed: 12/20/2022]
Abstract
Cell division in prokaryotes initiates with assembly of the Z-ring at midcell, which, in Escherichia coli, is tethered to the inner leaflet of the cytoplasmic membrane through a direct interaction with FtsA, a widely conserved actin homolog. The Z-ring is comprised of polymers of tubulin-like FtsZ and has been suggested to provide the force for constriction. Here, we demonstrate that FtsA exerts force on membranes causing redistribution of membrane architecture, robustly hydrolyzes ATP and directly engages FtsZ polymers in a reconstituted system. Phospholipid reorganization by FtsA occurs rapidly and is mediated by insertion of a C-terminal membrane targeting sequence (MTS) into the bilayer and further promoted by a nucleotide-dependent conformational change relayed to the MTS. FtsA also recruits FtsZ to phospholipid vesicles via a direct interaction with the FtsZ C-terminus and regulates FtsZ assembly kinetics. These results implicate the actin homolog FtsA in establishment of a Z-ring scaffold, while directly remodeling the membrane and provide mechanistic insight into localized cell wall remodeling, invagination and constriction at the onset of division.
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Affiliation(s)
| | | | - Jodi L Camberg
- Departments of Cell and Molecular Biology.,Nutrition and Food Sciences, The University of Rhode Island, Kingston, RI 02881, USA
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Zou Y, Li Y, Ekanayake SB, Dillon JAR. An Escherichia coli expression model reveals the species-specific function of FtsA from Neisseria gonorrhoeae in cell division. FEMS Microbiol Lett 2017; 364:3739240. [PMID: 28431102 DOI: 10.1093/femsle/fnx078] [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: 11/14/2016] [Accepted: 04/17/2017] [Indexed: 11/14/2022] Open
Abstract
Escherichia coli (Ec) has been used to study the function of cell division proteins from different microorganisms, especially when genetic tools are limited for studying these proteins in their native hosts. The expression of ftsA from Neisseria gonorrhoeae (Ng) disrupted cell division in E. coli resulting in a significant increase in cell length. In some cells, FtsANg localised to the division site and the poles of E. coli cells, but the majority of cells showed no specifical localisation. FtsANg did not complement an E. coli ftsA mutant strain. Bacterial two-hybrid and GST pull-down assays indicated that FtsANg interacted with FtsNEc, but no other cell division proteins from E. coli. This interaction was mediated through the 2A and 2B subdomains of FtsANg. This evidence suggests that the function of FtsANg is species specific.
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Affiliation(s)
- Yinan Zou
- Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, SK S7N 5E5, Canada.,Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, SK S7N 5E5, Canada
| | - Yan Li
- Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, SK S7N 5E5, Canada.,Department of Biology, College of Arts and Science, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Sanjaya B Ekanayake
- Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, SK S7N 5E5, Canada
| | - Jo-Anne R Dillon
- Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, SK S7N 5E5, Canada.,Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, SK S7N 5E5, Canada.,Department of Biology, College of Arts and Science, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
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Loose M, Zieske K, Schwille P. Reconstitution of Protein Dynamics Involved in Bacterial Cell Division. Subcell Biochem 2017; 84:419-444. [PMID: 28500535 DOI: 10.1007/978-3-319-53047-5_15] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Even simple cells like bacteria have precisely regulated cellular anatomies, which allow them to grow, divide and to respond to internal or external cues with high fidelity. How spatial and temporal intracellular organization in prokaryotic cells is achieved and maintained on the basis of locally interacting proteins still remains largely a mystery. Bulk biochemical assays with purified components and in vivo experiments help us to approach key cellular processes from two opposite ends, in terms of minimal and maximal complexity. However, to understand how cellular phenomena emerge, that are more than the sum of their parts, we have to assemble cellular subsystems step by step from the bottom up. Here, we review recent in vitro reconstitution experiments with proteins of the bacterial cell division machinery and illustrate how they help to shed light on fundamental cellular mechanisms that constitute spatiotemporal order and regulate cell division.
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Affiliation(s)
- Martin Loose
- Institute for Science and Technology Austria (IST Austria), Klosterneuburg, Austria.
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Abstract
A diverse set of protein polymers, structurally related to actin filaments contributes to the organization of bacterial cells as cytomotive or cytoskeletal filaments. This chapter describes actin homologs encoded by bacterial chromosomes. MamK filaments, unique to magnetotactic bacteria, help establishing magnetic biological compasses by interacting with magnetosomes. Magnetosomes are intracellular membrane invaginations containing biomineralized crystals of iron oxide that are positioned by MamK along the long-axis of the cell. FtsA is widespread across bacteria and it is one of the earliest components of the divisome to arrive at midcell, where it anchors the cell division machinery to the membrane. FtsA binds directly to FtsZ filaments and to the membrane through its C-terminus. FtsA shows altered domain architecture when compared to the canonical actin fold. FtsA's subdomain 1C replaces subdomain 1B of other members of the actin family and is located on the opposite side of the molecule. Nevertheless, when FtsA assembles into protofilaments, the protofilament structure is preserved, as subdomain 1C replaces subdomain IB of the following subunit in a canonical actin filament. MreB has an essential role in shape-maintenance of most rod-shaped bacteria. Unusually, MreB filaments assemble from two protofilaments in a flat and antiparallel arrangement. This non-polar architecture implies that both MreB filament ends are structurally identical. MreB filaments bind directly to membranes where they interact with both cytosolic and membrane proteins, thereby forming a key component of the elongasome. MreB filaments in cells are short and dynamic, moving around the long axis of rod-shaped cells, sensing curvature of the membrane and being implicated in peptidoglycan synthesis.
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Affiliation(s)
- Thierry Izoré
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Fusinita van den Ent
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
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Abstract
In bacteria and archaea, the most widespread cell division system is based on the tubulin homologue FtsZ protein, whose filaments form the cytokinetic Z-ring. FtsZ filaments are tethered to the membrane by anchors such as FtsA and SepF and are regulated by accessory proteins. One such set of proteins is responsible for Z-ring's spatiotemporal regulation, essential for the production of two equal-sized daughter cells. Here, we describe how our still partial understanding of the FtsZ-based cell division process has been progressed by visualising near-atomic structures of Z-rings and complexes that control Z-ring positioning in cells, most notably the MinCDE and Noc systems that act by negatively regulating FtsZ filaments. We summarise available data and how they inform mechanistic models for the cell division process.
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Haranahalli K, Tong S, Ojima I. Recent advances in the discovery and development of antibacterial agents targeting the cell-division protein FtsZ. Bioorg Med Chem 2016; 24:6354-6369. [PMID: 27189886 PMCID: PMC5157688 DOI: 10.1016/j.bmc.2016.05.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 04/29/2016] [Accepted: 05/03/2016] [Indexed: 01/21/2023]
Abstract
With the emergence of multidrug-resistant bacterial strains, there is a dire need for new drug targets for antibacterial drug discovery and development. Filamentous temperature sensitive protein Z (FtsZ), is a GTP-dependent prokaryotic cell division protein, sharing less than 10% sequence identity with the eukaryotic cell division protein, tubulin. FtsZ forms a dynamic Z-ring in the middle of the cell, leading to septation and subsequent cell division. Inhibition of the Z-ring blocks cell division, thus making FtsZ a highly attractive target. Various groups have been working on natural products and synthetic small molecules as inhibitors of FtsZ. This review summarizes the recent advances in the development of FtsZ inhibitors, focusing on those in the last 5years, but also includes significant findings in previous years.
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Affiliation(s)
| | - Simon Tong
- Department of Chemistry, Stony Brook University, Stony Brook, NY, USA
| | - Iwao Ojima
- Department of Chemistry, Stony Brook University, Stony Brook, NY, USA; Institute of Chemical Biology and Drug Discovery, Stony Brook University, Stony Brook, NY, USA.
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Abstract
Bacterial cell division is driven by the divisome, a ring-shaped protein complex organized by the bacterial tubulin homolog FtsZ. Although most of the division proteins in Escherichia coli have been identified, how they assemble into the divisome and synthesize the septum remains poorly understood. Recent studies suggest that the bacterial actin homolog FtsA plays a critical role in divisome assembly and acts synergistically with the FtsQLB complex to regulate the activity of the divisome. FtsEX, an ATP-binding cassette transporter-like complex, is also necessary for divisome assembly and inhibits division when its ATPase activity is inactivated. However, its role in division is not clear. Here, we find that FtsEX acts on FtsA to regulate both divisome assembly and activity. FtsX interacts with FtsA and this interaction is required for divisome assembly and inhibition of divisome function by ATPase mutants of FtsEX. Our results suggest that FtsEX antagonizes FtsA polymerization to promote divisome assembly and the ATPase mutants of FtsEX block divisome activity by locking FtsA in the inactive form or preventing FtsA from communicating with other divisome proteins. Because FtsEX is known to govern cell wall hydrolysis at the septum, our findings indicate that FtsEX acts on FtsA to promote divisome assembly and to coordinate cell wall synthesis and hydrolysis at the septum. Furthermore, our study provides evidence that FtsA mutants impaired for self-interaction are favored for division, and FtsW plays a critical role in divisome activation in addition to the FtsQLB complex.
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Standish AJ, Teh MY, Tran ENH, Doyle MT, Baker PJ, Morona R. Unprecedented Abundance of Protein Tyrosine Phosphorylation Modulates Shigella flexneri Virulence. J Mol Biol 2016; 428:4197-4208. [PMID: 27380737 DOI: 10.1016/j.jmb.2016.06.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 06/06/2016] [Accepted: 06/23/2016] [Indexed: 01/09/2023]
Abstract
Evidence is accumulating that protein tyrosine phosphorylation plays a crucial role in the ability of important human bacterial pathogens to cause disease. While most works have concentrated on its role in the regulation of a major bacterial virulence factor, the polysaccharide capsule, recent studies have suggested a much broader role for this post-translational modification. This prompted us to investigate protein tyrosine phosphorylation in the human pathogen Shigella flexneri. We first completed a tyrosine phosphoproteome, identifying 905 unique tyrosine phosphorylation sites on at least 573 proteins (approximately 15% of all proteins). This is the most tyrosine-phosphorylated sites and proteins in a single bacterium identified to date, substantially more than the level seen in eukaryotic cells. Most had not previously been identified and included proteins encoded by the virulence plasmid, which is essential for S. flexneri to invade cells and cause disease. In order to investigate the function of these phosphorylation sites in important virulence factors, phosphomimetic and ablative mutations were constructed in the type 3 secretion system ATPase Spa47 and the master virulence regulator VirB. This revealed that tyrosine residues phosphorylated in our study are critical for Spa47 and VirB activity, and tyrosine phosphorylation likely regulates their functional activity and subsequently the virulence of this major human pathogen. This study suggests that tyrosine phosphorylation plays a critical role in regulating a wide variety of virulence factors in the human pathogen S. flexneri and serves as a base for future studies defining its complete role.
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Affiliation(s)
- Alistair James Standish
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.
| | - Min Yan Teh
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Elizabeth Ngoc Hoa Tran
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Matthew Thomas Doyle
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Paul J Baker
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Renato Morona
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
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Laddomada F, Miyachiro MM, Dessen A. Structural Insights into Protein-Protein Interactions Involved in Bacterial Cell Wall Biogenesis. Antibiotics (Basel) 2016; 5:antibiotics5020014. [PMID: 27136593 PMCID: PMC4929429 DOI: 10.3390/antibiotics5020014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Revised: 03/15/2016] [Accepted: 04/09/2016] [Indexed: 12/30/2022] Open
Abstract
The bacterial cell wall is essential for survival, and proteins that participate in its biosynthesis have been the targets of antibiotic development efforts for decades. The biosynthesis of its main component, the peptidoglycan, involves the coordinated action of proteins that are involved in multi-member complexes which are essential for cell division (the “divisome”) and/or cell wall elongation (the “elongasome”), in the case of rod-shaped cells. Our knowledge regarding these interactions has greatly benefitted from the visualization of different aspects of the bacterial cell wall and its cytoskeleton by cryoelectron microscopy and tomography, as well as genetic and biochemical screens that have complemented information from high resolution crystal structures of protein complexes involved in divisome or elongasome formation. This review summarizes structural and functional aspects of protein complexes involved in the cytoplasmic and membrane-related steps of peptidoglycan biosynthesis, with a particular focus on protein-protein interactions whereby disruption could lead to the development of novel antibacterial strategies.
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Affiliation(s)
- Federica Laddomada
- Institut de Biologie Structurale (IBS), University Grenoble Alpes, Grenoble F-38044, France.
- Centre National de la Recherche Scientifique (CNRS), IBS, Grenoble F-38044, France.
- Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), IBS, Grenoble F-38044, France.
| | - Mayara M Miyachiro
- Brazilian National Laboratory for Biosciences (LNBio), CNPEM, Campinas, São Paulo 13083-100, Brazil.
| | - Andréa Dessen
- Institut de Biologie Structurale (IBS), University Grenoble Alpes, Grenoble F-38044, France.
- Centre National de la Recherche Scientifique (CNRS), IBS, Grenoble F-38044, France.
- Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), IBS, Grenoble F-38044, France.
- Brazilian National Laboratory for Biosciences (LNBio), CNPEM, Campinas, São Paulo 13083-100, Brazil.
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Busiek KK, Margolin W. Bacterial actin and tubulin homologs in cell growth and division. Curr Biol 2016; 25:R243-R254. [PMID: 25784047 DOI: 10.1016/j.cub.2015.01.030] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In contrast to the elaborate cytoskeletal machines harbored by eukaryotic cells, such as mitotic spindles, cytoskeletal structures detectable by typical negative stain electron microscopy are generally absent from bacterial cells. As a result, for decades it was thought that bacteria lacked cytoskeletal machines. Revolutions in genomics and fluorescence microscopy have confirmed the existence not only of smaller-scale cytoskeletal structures in bacteria, but also of widespread functional homologs of eukaryotic cytoskeletal proteins. The presence of actin, tubulin, and intermediate filament homologs in these relatively simple cells suggests that primitive cytoskeletons first arose in bacteria. In bacteria such as Escherichia coli, homologs of tubulin and actin directly interact with each other and are crucial for coordinating cell growth and division. The function and direct interactions between these proteins will be the focus of this review.
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Affiliation(s)
- Kimberly K Busiek
- Department of Microbiology and Molecular Genetics, University of Texas Medical School at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - William Margolin
- Department of Microbiology and Molecular Genetics, University of Texas Medical School at Houston, 6431 Fannin St., Houston, TX 77030, USA.
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Pichoff S, Du S, Lutkenhaus J. The bypass of ZipA by overexpression of FtsN requires a previously unknown conserved FtsN motif essential for FtsA-FtsN interaction supporting a model in which FtsA monomers recruit late cell division proteins to the Z ring. Mol Microbiol 2015; 95:971-87. [PMID: 25496259 DOI: 10.1111/mmi.12907] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/10/2014] [Indexed: 11/29/2022]
Abstract
Assembly of the divisome in Escherichia coli occurs in two temporally distinct steps. First, FtsZ filaments attached to the membrane through interaction with FtsA and ZipA coalesce into a Z ring at midcell. Then, additional proteins are recruited to the Z ring in a hierarchical manner to form a complete divisome, activated by the arrival of FtsN. Recently, we proposed that the interaction of FtsA with itself competes with its ability to recruit downstream division proteins (both require the IC domain of FtsA) and ZipA's essential function is to promote the formation of FtsA monomers. Here, we tested whether overexpression of a downstream division protein could make ZipA dispensable, presumably by shifting the FtsA equilibrium to monomers. Only overexpression of FtsN bypassed ZipA and a conserved motif in the cytoplasmic domain of FtsN was required for both the bypass and interaction with FtsA. Also, this cytoplasmic motif had to be linked to the periplasmic E domain of FtsN to bypass ZipA, indicating that linkage of FtsA to periplasmic components of the divisome through FtsN was essential under these conditions. These results are used to further elaborate our model for the role of FtsA in recruiting downstream division proteins.
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Affiliation(s)
- Sebastien Pichoff
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, 3901 Rainbow Blvd, Kansas City, KS, 66160, USA
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Modi K, Misra HS. Dr-FtsA, an actin homologue in Deinococcus radiodurans differentially affects Dr-FtsZ and Ec-FtsZ functions in vitro. PLoS One 2014; 9:e115918. [PMID: 25551229 PMCID: PMC4281207 DOI: 10.1371/journal.pone.0115918] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 11/29/2014] [Indexed: 11/24/2022] Open
Abstract
The Deinococcus radiodurans genome encodes homologues of divisome proteins including FtsZ and FtsA. FtsZ of this bacterium (Dr-FtsZ) has been recently characterized. In this paper, we study FtsA of D. radiodurans (Dr-FtsA) and its involvement in regulation of FtsZ function. Recombinant Dr-FtsA showed neither ATPase nor GTPase activity and its polymerization was ATP dependent. Interestingly, we observed that Dr-FtsA, when compared with E. coli FtsA (Ec-FtsA), has lower affinity for both Dr-FtsZ and Ec-FtsZ. Also, Dr-FtsA showed differential effects on GTPase activity and sedimentation characteristics of Dr-FtsZ and Ec-FtsZ. For instance, Dr-FtsA stimulated GTPase activity of Dr-FtsZ while GTPase activity of Ec-FtsZ was reduced in the presence of Dr-FtsA. Stimulation of GTPase activity of Dr-FtsZ by Dr-FtsA resulted in depolymerization of Dr-FtsZ. Dr-FtsA effects on GTPase activity and polymerization/depolymerisation characteristics of Dr-FtsZ did not change significantly in the presence of ATP. Recombinant E. coli expressing Dr-FtsA showed cell division inhibition in spite of in trans expression of Dr-FtsZ in these cells. These results suggested that Dr-FtsA, although it lacks ATPase activity, is still functional and differentially affects Dr-FtsZ and Ec-FtsZ function in vitro.
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Affiliation(s)
- Kruti Modi
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400 085, India
| | - Hari S. Misra
- Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, 400 085, India
- * E-mail:
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Szwedziak P, Wang Q, Bharat TAM, Tsim M, Löwe J. Architecture of the ring formed by the tubulin homologue FtsZ in bacterial cell division. eLife 2014; 3:e04601. [PMID: 25490152 PMCID: PMC4383033 DOI: 10.7554/elife.04601] [Citation(s) in RCA: 168] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 12/08/2014] [Indexed: 12/16/2022] Open
Abstract
Membrane constriction is a prerequisite for cell division. The most common membrane
constriction system in prokaryotes is based on the tubulin homologue FtsZ, whose
filaments in E. coli are anchored to the membrane by FtsA and enable
the formation of the Z-ring and divisome. The precise architecture of the FtsZ ring
has remained enigmatic. In this study, we report three-dimensional arrangements of
FtsZ and FtsA filaments in C. crescentus and E.
coli cells and inside constricting liposomes by means of electron
cryomicroscopy and cryotomography. In vivo and in vitro, the Z-ring is composed of a
small, single-layered band of filaments parallel to the membrane, creating a
continuous ring through lateral filament contacts. Visualisation of the in vitro
reconstituted constrictions as well as a complete tracing of the helical paths of the
filaments with a molecular model favour a mechanism of FtsZ-based membrane
constriction that is likely to be accompanied by filament sliding. DOI:http://dx.doi.org/10.7554/eLife.04601.001 Cell division is the process by which new cells are made. It is therefore vital for
the growth and development, and the regeneration and repair of damaged tissues. When
bacterial and animal cells divide, they must constrict their membrane inwards to
split a single cell into two. In most bacteria, this constriction is guided by a
ring-like structure that contains filaments of a protein called FtsZ. During cell
division, this structure forms around the inside edge of the cell and when it
contracts, it pulls the membrane inwards and causes the cell to constrict and
eventually divide. In recent years, this arrangement of FtsZ filaments has been intensively
investigated, giving rise to various theories about how it is made and how it works:
for example, some recent studies suggested that FtsZ does not form a continuous ring.
Nevertheless, many details about the cell division process remain unknown. Szwedziak, Wang et al. have now investigated this protein ring in two species of
bacteria by turning to advanced forms of microscopy to closely observe its structure
and how it works. This included mapping the ring in three dimensions. Contrary to
earlier reports that the FtsZ ring is discontinuous, in both a bacterium called
Caulobacter crescentus and another called Escherichia
coli, the ring forms a continuous shape made up of overlapping
filaments. Szwedziak, Wang et al. then increased the levels of two of the ring's main
components: the FtsZ protein that forms the filaments and a protein that anchors
these filaments to the cell membrane. This caused the modified cells to constrict and
divide at extra sites, which resulted in the formation of abnormally small cells.
These findings suggest that these two ring components by themselves are able to
generate both the structures and force required for cell constriction. This is
supported by the fact that when they were introduced into artificial cell-like
structures, these proteins spontaneously self-organised into rings and triggered
constriction where they formed. Szwedziak, Wang et al. propose that constriction only starts once the FtsZ protein
forms a closed ring and that the ring's overlapping filaments slide along each other
to further decrease its diameter and constrict the cell. The degree of filament
overlap likely also increases with constriction, requiring filaments to be shortened
to maintain sliding. This shortening, along with sliding, could provide a mechanism
by which to drive the constriction process. This work will be followed by even more detailed studies in order to understand the
process of bacterial cell division at the atomic scale and how the cell's wall is
reshaped during the process. In the long run, intricate knowledge of how a bacterial
cell divides might enable the design of new classes of antibiotics targeting the
molecular machinery involved. DOI:http://dx.doi.org/10.7554/eLife.04601.002
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Affiliation(s)
- Piotr Szwedziak
- Structural Studies Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Qing Wang
- Structural Studies Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Tanmay A M Bharat
- Structural Studies Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Matthew Tsim
- Structural Studies Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Jan Löwe
- Structural Studies Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
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Abstract
UNLABELLED Together with ATP, the C-terminal region of the essential streptococcal FtsA protein acts as an intramolecular switch to promote its polymerization and attachment to the membrane. During septation, FtsA is known to anchor the constricting FtsZ ring and, subsequently, the divisome to the membrane. Truncation of the C terminus of the streptococcal FtsA (FtsAΔCt) facilitates a more rapid ATP-dependent polymerization in solution than is seen with the full-length protein (FtsA(+)). The FtsAΔCt polymers are more organized and compact than those formed in solution by FtsA(+), resembling the shape of the membrane-associated FtsA(+) polymers. We find that ATP, besides being needed for polymerization, is required for the attachment of FtsA(+) to lipid monolayers and to vesicle membranes. We propose a model in which the binding of ATP activates a switch favoring the polymerization of FtsA and at the same time driving the amphipathic helix at its C terminus to become attached to the membrane. Conversely, when FtsA is in the cytoplasm, the C terminus is not engaged in the attachment to the membrane, and it obstructs polymerization. ATP-dependent polymerization of FtsA inside membrane vesicles causes vesicle shrinkage, suggesting that, besides providing a membrane attachment for FtsZ, the FtsA C terminus may also introduce local alterations in the membrane to facilitate septation. IMPORTANCE FtsA is a protein needed in many bacteria to construct a septum that divides one fully grown cell, producing two daughters. We show that the region located at the C-terminal end of the Streptococcus pneumoniae FtsA protein works as a switch triggered by ATP, a molecule that stores energy. This region contains an amphipathic helix that obstructs the assembly of FtsA into polymers in the cytoplasm. In the presence of ATP, the obstruction is removed by switching the position of the helix. The switch directs the helix to the membrane and simultaneously facilitates the polymerization of the protein. The accumulation of FtsA molecules at the membrane causes distortions, an effect produced also by proteins such as MinD, MreB, and SepF that also contain amphipathic helixes as membrane attachment devices. In the case of FtsA, these distortions may also facilitate the initial events that lead to the division of bacteria.
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Herricks JR, Nguyen D, Margolin W. A thermosensitive defect in the ATP binding pocket of FtsA can be suppressed by allosteric changes in the dimer interface. Mol Microbiol 2014; 94:713-27. [PMID: 25213228 DOI: 10.1111/mmi.12790] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2014] [Indexed: 11/30/2022]
Abstract
In Escherichia coli, initial assembly of the Z ring for cell division requires FtsZ plus the essential Z ring-associated proteins FtsA and ZipA. Thermosensitive mutations in ftsA, such as ftsA27, map in or near its ATP binding pocket and result in cell division arrest at non-permissive temperatures. We found that purified wild-type FtsA bound and hydrolysed ATP, whereas FtsA27 was defective in both activities. FtsA27 was also less able to localize to the Z ring in vivo. To investigate the role of ATP transactions in FtsA function in vivo, we isolated intragenic suppressors of ftsA27. Suppressor lesions in the ATP site restored the ability of FtsA27 to compete with ZipA at the Z ring, and enhanced ATP binding and hydrolysis in vitro. Notably, suppressors outside of the ATP binding site, including some mapping to the FtsA-FtsA subunit interface, also enhanced ATP transactions and exhibited gain of function phenotypes in vivo. These results suggest that allosteric effects, including changes in oligomeric state, may influence the ability of FtsA to bind and/or hydrolyse ATP.
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Affiliation(s)
- Jennifer R Herricks
- Department of Microbiology & Molecular Genetics, University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX, 77030, USA
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Loose M, Mitchison TJ. The bacterial cell division proteins FtsA and FtsZ self-organize into dynamic cytoskeletal patterns. Nat Cell Biol 2014; 16:38-46. [PMID: 24316672 PMCID: PMC4019675 DOI: 10.1038/ncb2885] [Citation(s) in RCA: 259] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 10/28/2013] [Indexed: 12/16/2022]
Abstract
Bacterial cytokinesis is commonly initiated by the Z-ring, a cytoskeletal structure that assembles at the site of division. Its primary component is FtsZ, a tubulin superfamily GTPase, which is recruited to the membrane by the actin-related protein FtsA. Both proteins are required for the formation of the Z-ring, but if and how they influence each other's assembly dynamics is not known. Here, we reconstituted FtsA-dependent recruitment of FtsZ polymers to supported membranes, where both proteins self-organize into complex patterns, such as fast-moving filament bundles and chirally rotating rings. Using fluorescence microscopy and biochemical perturbations, we found that these large-scale rearrangements of FtsZ emerge from its polymerization dynamics and a dual, antagonistic role of FtsA: recruitment of FtsZ filaments to the membrane and negative regulation of FtsZ organization. Our findings provide a model for the initial steps of bacterial cell division and illustrate how dynamic polymers can self-organize into large-scale structures.
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Affiliation(s)
- Martin Loose
- Department of Systems Biology, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
| | - Timothy J. Mitchison
- Department of Systems Biology, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
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Abstract
For many years, bacteria were considered rather simple organisms, but the dogmatic notion that subcellular organization is a eukaryotic trait has been overthrown for more than a decade. The discovery of homologues of the eukaryotic cytoskeletal proteins actin, tubulin, and intermediate filaments in bacteria has been instrumental in changing this view. Over the past few years, we have gained an incredible level of insight into the diverse family of bacterial actins and their molecular workings. Here we review the functional, biochemical, and structural features of the most well-studied bacterial actins.
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Affiliation(s)
- Ertan Ozyamak
- Department of Plant and Microbial Biology, University of California , Berkeley, California 94720, United States
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Pérez Rodriguez MA, Guo X. Biomacromolecular localization in bacterial cells by the diffusion and capture mechanism. ANN MICROBIOL 2013. [DOI: 10.1007/s13213-012-0596-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Hsin J, Fu R, Huang KC. Dimer dynamics and filament organization of the bacterial cell division protein FtsA. J Mol Biol 2013; 425:4415-26. [PMID: 23871894 DOI: 10.1016/j.jmb.2013.07.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 06/25/2013] [Accepted: 07/11/2013] [Indexed: 01/22/2023]
Abstract
FtsA is a bacterial actin homolog and one of the core proteins involved in cell division. While previous studies have demonstrated the capability of FtsA to polymerize, little is known about its polymerization state in vivo or if polymerization is necessary for FtsA function. Given that one function of FtsA is to tether FtsZ filaments to the membrane, in vivo polymerization of FtsA imposes geometric constraints and requires a specific polymer curvature direction. Here, we report a series of molecular dynamics simulations probing the structural dynamics of FtsA as a dimer and as a tetrameric single filament. We found that the FtsA polymer exhibits a preferred bending direction that would allow for its placement parallel with FtsZ polymers underneath the cytoplasmic membrane. We also identified key interfacial amino acids that mediate FtsA-FtsA interaction and propose that some amino acids play more critical roles than others. We performed in silico mutagenesis on FtsA and demonstrated that, while a moderate mutation at the polymerization interface does not significantly affect polymer properties such as bending direction and association strength, more drastic mutations change both features and could lead to non-functional FtsA.
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Affiliation(s)
- Jen Hsin
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
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Abstract
The first step in bacterial cytokinesis is the assembly of a stable but dynamic cytokinetic ring made up of the essential tubulin homolog FtsZ at the future site of division. Although FtsZ and its role in cytokinesis have been studied extensively, the precise architecture of the in vivo medial FtsZ ring (Z ring) is not well understood. Recent advances in superresolution imaging suggest that the Z ring comprises short, discontinuous, and loosely bundled FtsZ polymers, some of which are tethered to the membrane. A diverse array of regulatory proteins modulate the assembly, stability, and disassembly of the Z ring via direct interactions with FtsZ. Negative regulators of FtsZ play a critical role in ensuring the accurate positioning of FtsZ at the future site of division and in maintaining Z ring dynamics by controlling FtsZ polymer assembly/disassembly processes. Positive regulators of FtsZ are essential for tethering FtsZ polymers to the membrane and promoting the formation of stabilizing lateral interactions, permitting assembly of a mature Z ring. The past decade has seen the identification of several factors that promote FtsZ assembly, presumably through a variety of distinct molecular mechanisms. While a few of these proteins are broadly conserved, many positive regulators of FtsZ assembly are limited to small groups of closely related organisms, suggesting that FtsZ assembly is differentially modulated across bacterial species. In this review, we focus on the roles of positive regulators in Z ring assembly and in maintaining the integrity of the cytokinetic ring during the early stages of division.
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Assembly of Bacillus subtilis FtsA: effects of pH, ionic strength and nucleotides on FtsA assembly. Int J Biol Macromol 2012; 52:170-6. [PMID: 23036588 DOI: 10.1016/j.ijbiomac.2012.09.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 08/18/2012] [Accepted: 09/25/2012] [Indexed: 11/23/2022]
Abstract
In this work, the assembly of purified Bacillus subtilis FtsA was analyzed by several complimentary techniques. FtsA assembled to form filaments and bundles and the polymers disassembled upon dilution. FtsA assembled more efficiently at pH 6.0 as compared to that at pH 7.0 or 8.0 and high salt inhibited the assembly of FtsA. FtsA was found to hydrolyze ATP in vitro; however, neither ATP nor ADP influenced the assembly kinetics of FtsA. Though FtsA is a homologue of actin, cytochalasin D did not inhibit the assembly of FtsA. Interestingly, a hydrophobic molecule, 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid, inhibited the assembly of FtsA.
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Affiliation(s)
- Jennifer R Juarez
- Department of Microbiology and Molecular Genetics, University of Texas Medical School at Houston, Houston TX, USA.
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