1
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Zhang Q, Wan M, Mao Y. Membrane-dependent actin polymerization mediated by the Legionella pneumophila effector protein MavH. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.24.525393. [PMID: 36747622 PMCID: PMC9900769 DOI: 10.1101/2023.01.24.525393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
L. pneumophila propagates in eukaryotic cells within a specialized niche, the Legionella -containing vacuole (LCV). The infection process is controlled by over 330 effector proteins delivered through the type IV secretion system. In this study, we report that the Legionella MavH effector harbors a lipid-binding domain that specifically recognizes PI(3)P (phosphatidylinositol 3-phosphate) and localizes to endosomes when ectopically expressed. We show that MavH recruits host actin capping proteins (CP) and actin to the endosome via its CP interacting (CPI) motif and WH2-like actin-binding domain, respectively. In vitro assays revealed that MavH stimulates robust actin polymerization only in the presence of PI(3)P-containing liposomes and the recruitment of CP by MavH negatively regulates F-actin density at the membrane. Furthermore, in L. pneumophila -infected cells, MavH can be detected around the LCV at the very early stage of infection. Together, our results reveal a novel mechanism of membrane-dependent actin polymerization catalyzed by MavH that may play a role at the early stage of L. pneumophila infection by regulating host actin dynamics.
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Affiliation(s)
- Qing Zhang
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Min Wan
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Yuxin Mao
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.,Corresponding Author: , Telephone: 607-255-0783
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2
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Lockwood DC, Amin H, Costa TRD, Schroeder GN. The Legionella pneumophila Dot/Icm type IV secretion system and its effectors. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35639581 DOI: 10.1099/mic.0.001187] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
To prevail in the interaction with eukaryotic hosts, many bacterial pathogens use protein secretion systems to release virulence factors at the host–pathogen interface and/or deliver them directly into host cells. An outstanding example of the complexity and sophistication of secretion systems and the diversity of their protein substrates, effectors, is the Defective in organelle trafficking/Intracellular multiplication (Dot/Icm) Type IVB secretion system (T4BSS) of
Legionella pneumophila
and related species.
Legionella
species are facultative intracellular pathogens of environmental protozoa and opportunistic human respiratory pathogens. The Dot/Icm T4BSS translocates an exceptionally large number of effectors, more than 300 per
L. pneumophila
strain, and is essential for evasion of phagolysosomal degradation and exploitation of protozoa and human macrophages as replicative niches. Recent technological advancements in the imaging of large protein complexes have provided new insight into the architecture of the T4BSS and allowed us to propose models for the transport mechanism. At the same time, significant progress has been made in assigning functions to about a third of
L. pneumophila
effectors, discovering unprecedented new enzymatic activities and concepts of host subversion. In this review, we describe the current knowledge of the workings of the Dot/Icm T4BSS machinery and provide an overview of the activities and functions of the to-date characterized effectors in the interaction of
L. pneumophila
with host cells.
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Affiliation(s)
- Daniel C Lockwood
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, BT9 7BL, Northern Ireland, UK
| | - Himani Amin
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, SW7 2AZ, UK
| | - Tiago R D Costa
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, SW7 2AZ, UK
| | - Gunnar N Schroeder
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, BT9 7BL, Northern Ireland, UK
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3
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Murata M, Kanamori R, Kitao T, Kubori T, Nagai H, Tagaya M, Arasaki K. Requirement of phosphatidic acid binding for distribution of bacterial protein targeting syntaxin 17. J Cell Sci 2022; 135:274561. [DOI: 10.1242/jcs.259538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 02/17/2022] [Indexed: 11/20/2022] Open
Abstract
A gram-negative bacterium, Legionella pneumophila is known to manipulate the host cellular functions. In these manipulations, bacterial proteins called Legionella effectors that L. pneumophila secretes into the host cytosol are necessary. A Legionella effector, Lpg1137, was identified as a serine protease responsible for degradation of syntaxin 17 (Stx17). However, how Lpg1137 can specifically recognize and degrade Stx17 remains unknown. Given that Stx17 is localized in the ER/mitochondria-associated membrane (MAM)/mitochondria, Lpg1137 likely distributes to these compartments to recognize Stx17. Here we show that the C-terminal region of Lpg1137 binds to phosphatidic acid (PA), a MAM/mitochondria-enriched phospholipid, and that this binding is required for the correct intracellular distribution of Lpg1137. Two basic residues in the C-terminal region are required for PA binding and their mutation causes mislocalization of Lpg1137. This mutant fails to degrade Stx17 while retaining a protease activity. Taken together, our data reveal that Lpg1137 utilizes PA for its distribution to the membranous compartments in which Stx17 is localized.
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Affiliation(s)
- Misaki Murata
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan
| | - Riku Kanamori
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan
| | - Tomoe Kitao
- Department of Microbiology, Graduate School of Medicine, Gifu University, 1-1 Yanagito, Gifu 501-1194, Japan
| | - Tomoko Kubori
- Department of Microbiology, Graduate School of Medicine, Gifu University, 1-1 Yanagito, Gifu 501-1194, Japan
- G-CHAIN, Gifu University, 1-1 Yanagito, Gifu 501-1194, Japan
| | - Hiroki Nagai
- Department of Microbiology, Graduate School of Medicine, Gifu University, 1-1 Yanagito, Gifu 501-1194, Japan
- G-CHAIN, Gifu University, 1-1 Yanagito, Gifu 501-1194, Japan
| | - Mitsuo Tagaya
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan
| | - Kohei Arasaki
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan
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4
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Glycosylating Effectors of Legionella pneumophila: Finding the Sweet Spots for Host Cell Subversion. Biomolecules 2022; 12:biom12020255. [PMID: 35204756 PMCID: PMC8961657 DOI: 10.3390/biom12020255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 01/30/2022] [Accepted: 01/31/2022] [Indexed: 02/04/2023] Open
Abstract
Work over the past two decades clearly defined a significant role of glycosyltransferase effectors in the infection strategy of the Gram-negative, respiratory pathogen Legionella pneumophila. Identification of the glucosyltransferase effectors Lgt1-3, specifically modifying elongation factor eEF1A, disclosed a novel mechanism of host protein synthesis manipulation by pathogens and illuminated its impact on the physiological state of the target cell, in particular cell cycle progression and immune and stress responses. Recent characterization of SetA as a general O-glucosyltransferase with a wide range of targets including the proteins Rab1 and Snx1, mediators of membrane transport processes, and the discovery of new types of glycosyltransferases such as LtpM and SidI indicate that the vast effector arsenal might still hold more so-far unrecognized family members with new catalytic features and substrates. In this article, we review our current knowledge regarding these fascinating biomolecules and discuss their role in introducing new or overriding endogenous post-translational regulatory mechanisms enabling the subversion of eukaryotic cells by L. pneumophila.
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5
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Iyer S, Das C. The unity of opposites: Strategic interplay between bacterial effectors to regulate cellular homeostasis. J Biol Chem 2021; 297:101340. [PMID: 34695417 PMCID: PMC8605245 DOI: 10.1016/j.jbc.2021.101340] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 10/15/2021] [Accepted: 10/20/2021] [Indexed: 11/23/2022] Open
Abstract
Legionella pneumophila is a facultative intracellular pathogen that uses the Dot/Icm Type IV secretion system (T4SS) to translocate many effectors into its host and establish a safe, replicative lifestyle. The bacteria, once phagocytosed, reside in a vacuolar structure known as the Legionella-containing vacuole (LCV) within the host cells and rapidly subvert organelle trafficking events, block inflammatory responses, hijack the host ubiquitination system, and abolish apoptotic signaling. This arsenal of translocated effectors can manipulate the host factors in a multitude of different ways. These proteins also contribute to bacterial virulence by positively or negatively regulating the activity of one another. Such effector-effector interactions, direct and indirect, provide the delicate balance required to maintain cellular homeostasis while establishing itself within the host. This review summarizes the recent progress in our knowledge of the structure-function relationship and biochemical mechanisms of select effector pairs from Legionella that work in opposition to one another, while highlighting the diversity of biochemical means adopted by this intracellular pathogen to establish a replicative niche within host cells.
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Affiliation(s)
- Shalini Iyer
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA.
| | - Chittaranjan Das
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA.
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6
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Budowa IV systemu sekrecji Legionella pneumophilai jego znaczenie w patogenezie. POSTEP HIG MED DOSW 2021. [DOI: 10.2478/ahem-2021-0023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstrakt
Bakterie Legionella pneumophila w środowisku naturalnym pasożytują wewnątrz komórek wybranych gatunków pierwotniaków, a po przedostaniu się do sztucznych systemów dystrybucji wody stają się ważnym czynnikiem etiologicznym zapalenia płuc u ludzi. Główną cechą determinującą patogenność tych bakterii jest zdolność do życia i replikacji w makrofagach płucnych, czyli w komórkach wyspecjalizowanych do fagocytozy, zabijania i trawienia mikroorganizmów. Warunkiem wstępnym rozwoju infekcji jest przełamanie mechanizmów bójczych makrofagów i utworzenie wakuoli replikacyjnej LCV (Legionella containing vacuole). Biogeneza wakuoli LCV jest możliwa dzięki sprawnemu funkcjonowaniu IV systemu sekrecji Dot/Icm, który jest wielobiałkowym, złożonym kompleksem umiejscowionym w wewnętrznej i zewnętrznej membranie osłony komórkowej bakterii. System Dot/Icm liczy 27 elementów, na które składają się m.in. kompleks rdzeniowo-transmembranowy, tworzący strukturalny szkielet całego systemu oraz kompleks białek sprzęgających. Geny kodujące komponenty systemu Dot/Icm są zorganizowane na dwóch regionach chromosomu bak-teryjnego. System sekrecji Dot/Icm umożliwia L. pneumophila wprowadzenie do cytozolu komórki gospodarza ponad 300 białek efektorowych, których skoordynowane działanie powoduje utrzymanie integralności błony wakuoli replikacyjnej oraz pozwala na manipulowanie różnymi procesami komórki. Ważnym elementem strategii wewnątrzkomórkowego namnażania się L. pneumophila jest modulowanie transportu pęcherzykowego, interakcja z retikulum endoplazmatycznym oraz zakłócenie biosyntezy białek, procesów autofagii i apoptozy komórki gospodarza. Poznanie złożonych mechanizmów regulacji i funkcji białek efektorowych systemu Dot/Icm ma decydujące znaczenie w zapobieganiu i leczeniu choroby legionistów.
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7
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Liu K, Kong L, Graham DB, Carey KL, Xavier RJ. SAC1 regulates autophagosomal phosphatidylinositol-4-phosphate for xenophagy-directed bacterial clearance. Cell Rep 2021; 36:109434. [PMID: 34320354 PMCID: PMC8327279 DOI: 10.1016/j.celrep.2021.109434] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/21/2020] [Accepted: 07/01/2021] [Indexed: 02/07/2023] Open
Abstract
Phosphoinositides are important molecules in lipid signaling, membrane identity, and trafficking that are spatiotemporally controlled by factors from both mammalian cells and intracellular pathogens. Here, using small interfering RNA (siRNA) directed against phosphoinositide kinases and phosphatases, we screen for regulators of the host innate defense response to intracellular bacterial replication. We identify SAC1, a transmembrane phosphoinositide phosphatase, as an essential regulator of xenophagy. Depletion or inactivation of SAC1 compromises fusion between Salmonella-containing autophagosomes and lysosomes, leading to increased bacterial replication. Mechanistically, the loss of SAC1 results in aberrant accumulation of phosphatidylinositol-4-phosphate [PI(4)P] on Salmonella-containing autophagosomes, thus facilitating recruitment of SteA, a PI(4)P-binding Salmonella effector protein, which impedes lysosomal fusion. Replication of Salmonella lacking SteA is suppressed by SAC-1-deficient cells, however, demonstrating bacterial adaptation to xenophagy. Our findings uncover a paradigm in which a host protein regulates the level of its substrate and impairs the function of a bacterial effector during xenophagy.
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Affiliation(s)
- Kai Liu
- Center for Computational and Integrative Biology, Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Lingjia Kong
- Center for Computational and Integrative Biology, Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Daniel B Graham
- Center for Computational and Integrative Biology, Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; Klarman Cell Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Ramnik J Xavier
- Center for Computational and Integrative Biology, Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; Klarman Cell Observatory, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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8
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Li G, Liu H, Luo ZQ, Qiu J. Modulation of phagosome phosphoinositide dynamics by a Legionella phosphoinositide 3-kinase. EMBO Rep 2021; 22:e51163. [PMID: 33492731 DOI: 10.15252/embr.202051163] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 12/06/2020] [Accepted: 12/21/2020] [Indexed: 12/12/2022] Open
Abstract
The phagosome harboring the bacterial pathogen Legionella pneumophila is known to be enriched with phosphatidylinositol 4-phosphate (PtdIns4P), which is important for anchoring a subset of its virulence factors and potentially for signaling events implicated in the biogenesis of the Legionella-containing vacuole (LCV) that supports intracellular bacterial growth. Here we demonstrate that the effector MavQ is a phosphoinositide 3-kinase that specifically catalyzes the conversion of phosphatidylinositol (PtdIns) into PtdIns3P. The product of MavQ is subsequently phosphorylated by the effector LepB to yield PtdIns(3,4)P2, whose 3-phosphate is then removed by another effector SidF to generate PtdIns4P. We also show that MavQ is associated with the LCV and the ∆mavQ mutant displays phenotypes in the anchoring of a PtdIns4P-binding effector similar to those of ∆lepB or ∆sidF mutants. Our results establish a mechanism of de novo PtdIns4P biosynthesis by L. pneumophila via a catalysis axis comprised of MavQ, LepB, and SidF on the surface of its phagosome.
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Affiliation(s)
- Gen Li
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Hongtao Liu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Zhao-Qing Luo
- Purdue Institute for Inflammation, Immunology and Infectious Disease and Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Jiazhang Qiu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
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9
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Tascón I, Li X, Lucas M, Nelson D, Vidaurrazaga A, Lin YH, Rojas AL, Hierro A, Machner MP. Structural insight into the membrane targeting domain of the Legionella deAMPylase SidD. PLoS Pathog 2020; 16:e1008734. [PMID: 32853279 PMCID: PMC7480848 DOI: 10.1371/journal.ppat.1008734] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 09/09/2020] [Accepted: 06/22/2020] [Indexed: 12/20/2022] Open
Abstract
AMPylation, the post-translational modification with adenosine monophosphate (AMP), is catalyzed by effector proteins from a variety of pathogens. Legionella pneumophila is thus far the only known pathogen that, in addition to encoding an AMPylase (SidM/DrrA), also encodes a deAMPylase, called SidD, that reverses SidM-mediated AMPylation of the vesicle transport GTPase Rab1. DeAMPylation is catalyzed by the N-terminal phosphatase-like domain of SidD. Here, we determined the crystal structure of full length SidD including the uncharacterized C-terminal domain (CTD). A flexible loop rich in aromatic residues within the CTD was required to target SidD to model membranes in vitro and to the Golgi apparatus within mammalian cells. Deletion of the loop (Δloop) or substitution of its aromatic phenylalanine residues rendered SidD cytosolic, showing that the hydrophobic loop is the primary membrane-targeting determinant of SidD. Notably, deletion of the two terminal alpha helices resulted in a CTD variant incapable of discriminating between membranes of different composition. Moreover, a L. pneumophila strain producing SidDΔloop phenocopied a L. pneumophila ΔsidD strain during growth in mouse macrophages and displayed prolonged co-localization of AMPylated Rab1 with LCVs, thus revealing that membrane targeting of SidD via its CTD is a critical prerequisite for its ability to catalyze Rab1 deAMPylation during L. pneumophila infection.
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Affiliation(s)
- Igor Tascón
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Xiao Li
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - María Lucas
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - D’anna Nelson
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ander Vidaurrazaga
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Yi-Han Lin
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Adriana L. Rojas
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Aitor Hierro
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
- Ikerbasque, Basque Foundation for Science, Maria Diaz de Haro, Bilbao, Spain
- * E-mail: (AH); (MPM)
| | - Matthias P. Machner
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail: (AH); (MPM)
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10
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Portlock TJ, Tyson JY, Dantu SC, Rehman S, White RC, McIntire IE, Sewell L, Richardson K, Shaw R, Pandini A, Cianciotto NP, Garnett JA. Structure, Dynamics and Cellular Insight Into Novel Substrates of the Legionella pneumophila Type II Secretion System. Front Mol Biosci 2020; 7:112. [PMID: 32656228 PMCID: PMC7325957 DOI: 10.3389/fmolb.2020.00112] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 05/12/2020] [Indexed: 12/13/2022] Open
Abstract
Legionella pneumophila is a Gram-negative bacterium that is able to replicate within a broad range of aquatic protozoan hosts. L. pneumophila is also an opportunistic human pathogen that can infect macrophages and epithelia in the lung and lead to Legionnaires’ disease. The type II secretion system is a key virulence factor of L. pneumophila and is used to promote bacterial growth at low temperatures, regulate biofilm formation, modulate host responses to infection, facilitate bacterial penetration of mucin gels and is necessary for intracellular growth during the initial stages of infection. The L. pneumophila type II secretion system exports at least 25 substrates out of the bacterium and several of these, including NttA to NttG, contain unique amino acid sequences that are generally not observed outside of the Legionella genus. NttA, NttC, and NttD are required for infection of several amoebal species but it is unclear what influence other novel substrates have within their host. In this study, we show that NttE is required for optimal infection of Acanthamoeba castellanii and Vermamoeba vermiformis amoeba and is essential for the typical colony morphology of L. pneumophila. In addition, we report the atomic structures of NttA, NttC, and NttE and through a combined biophysical and biochemical hypothesis driven approach we propose novel functions for these substrates during infection. This work lays the foundation for future studies into the mechanistic understanding of novel type II substrate functions and how these relate to L. pneumophila ecology and disease.
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Affiliation(s)
- Theo J Portlock
- Centre for Host-Microbiome Interactions, Dental Institute, King's College London, London, United Kingdom.,Department of Chemistry and Biochemistry, School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Jessica Y Tyson
- Department of Microbiology and Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Sarath C Dantu
- Department of Computer Science, Brunel University London, Uxbridge, United Kingdom
| | - Saima Rehman
- Centre for Host-Microbiome Interactions, Dental Institute, King's College London, London, United Kingdom
| | - Richard C White
- Department of Microbiology and Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Ian E McIntire
- Department of Microbiology and Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Lee Sewell
- Centre for Host-Microbiome Interactions, Dental Institute, King's College London, London, United Kingdom
| | - Katherine Richardson
- Department of Chemistry and Biochemistry, School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Rosie Shaw
- Department of Chemistry and Biochemistry, School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Alessandro Pandini
- Department of Computer Science, Brunel University London, Uxbridge, United Kingdom
| | - Nicholas P Cianciotto
- Department of Microbiology and Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - James A Garnett
- Centre for Host-Microbiome Interactions, Dental Institute, King's College London, London, United Kingdom.,Department of Chemistry and Biochemistry, School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
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11
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Swart AL, Hilbi H. Phosphoinositides and the Fate of Legionella in Phagocytes. Front Immunol 2020; 11:25. [PMID: 32117224 PMCID: PMC7025538 DOI: 10.3389/fimmu.2020.00025] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/08/2020] [Indexed: 01/28/2023] Open
Abstract
Legionella pneumophila is the causative agent of a severe pneumonia called Legionnaires' disease. The environmental bacterium replicates in free-living amoebae as well as in lung macrophages in a distinct compartment, the Legionella-containing vacuole (LCV). The LCV communicates with a number of cellular vesicle trafficking pathways and is formed by a plethora of secreted bacterial effector proteins, which target host cell proteins and lipids. Phosphoinositide (PI) lipids are pivotal determinants of organelle identity, membrane dynamics and vesicle trafficking. Accordingly, eukaryotic cells tightly regulate the production, turnover, interconversion, and localization of PI lipids. L. pneumophila modulates the PI pattern in infected cells for its own benefit by (i) recruiting PI-decorated vesicles, (ii) producing effectors acting as PI interactors, phosphatases, kinases or phospholipases, and (iii) subverting host PI metabolizing enzymes. The PI conversion from PtdIns(3)P to PtdIns(4)P represents a decisive step during LCV maturation. In this review, we summarize recent progress on elucidating the strategies, by which L. pneumophila subverts host PI lipids to promote LCV formation and intracellular replication.
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Affiliation(s)
- A Leoni Swart
- Faculty of Medicine, Institute of Medical Microbiology, University of Zürich, Zurich, Switzerland
| | - Hubert Hilbi
- Faculty of Medicine, Institute of Medical Microbiology, University of Zürich, Zurich, Switzerland
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