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Vidovic S, Taylor R, Hedderley D, Fletcher GC, Wei N. Detection of non-pathogenic and pathogenic populations of Vibrio parahaemolyticus in various samples by the conventional, quantitative and droplet digital PCRs. Sci Rep 2024; 14:4137. [PMID: 38374337 PMCID: PMC10876695 DOI: 10.1038/s41598-024-54753-y] [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: 01/08/2024] [Accepted: 02/15/2024] [Indexed: 02/21/2024] Open
Abstract
In this study, three generations of polymerase chain reaction (PCR) assays: (i) conventional PCR, (ii) qPCR and (iii) droplet digital PCR (ddPCR), were systematically tested for their abilities to detect non-pathogenic and pathogenic populations of Vibrio parahaemolyticus. The limit of detection (LOD) for the ddPCR was 1.1 pg/µL of purified DNA, followed by the qPCR (5.6 pg/µL) and the conventional PCR (8.8 pg/µL). Regarding the LOD for V. parahaemolyticus cells, the ddPCR assay was able to detect 29 cells, followed by the conventional PCR assay (58 cells) and the qPCR assay (115 cells). Regarding the sensitivities to detect this pathogen from PCR inhibition prone samples (naturally contaminated mussels), the ddPCR assay significantly outperformed the conventional PCR and qPCR. The ddPCR assay was able to consistently detect non-pathogenic and pathogenic populations of V. parahaemolyticus from naturally contaminated mussels, indicating its tolerance to various PCR inhibitors. This study also revealed the significant difference between conventional PCR and qPCR. The conventional PCR assay showed significantly greater sensitivity than that of the qPCR assay in detecting V. parahaemolyticus in crude samples, whereas the qPCR assay showed better sensitivity in detecting the presence of V. parahaemolyticus in purified DNA samples.
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Affiliation(s)
- Sinisa Vidovic
- The New Zealand Institute for Plant and Food Research Limited, 120 Mount Albert Road, Sandringham, 1025, Auckland, New Zealand.
| | - Roland Taylor
- The New Zealand Institute for Plant and Food Research Limited, 120 Mount Albert Road, Sandringham, 1025, Auckland, New Zealand
| | - Duncan Hedderley
- The New Zealand Institute for Plant and Food Research Limited, Palmerston North, New Zealand
| | - Graham C Fletcher
- The New Zealand Institute for Plant and Food Research Limited, 120 Mount Albert Road, Sandringham, 1025, Auckland, New Zealand
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2
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Restrepo-Benavides M, Lozano-Arce D, Gonzalez-Garcia LN, Báez-Aguirre F, Ariza-Aranguren G, Faccini D, Zambrano MM, Jiménez P, Fernández-Bravo A, Restrepo S, Guevara-Suarez M. Unveiling potential virulence determinants in Vibrio isolates from Anadara tuberculosa through whole genome analyses. Microbiol Spectr 2024; 12:e0292823. [PMID: 38189292 PMCID: PMC10846245 DOI: 10.1128/spectrum.02928-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 11/14/2023] [Indexed: 01/09/2024] Open
Abstract
The genus Vibrio includes pathogenic bacteria able to cause disease in humans and aquatic organisms, leading to disease outbreaks and significant economic losses in the fishery industry. Despite much work on Vibrio in several marine organisms, no specific studies have been conducted on Anadara tuberculosa. This is a commercially important bivalve species, known as "piangua hembra," along Colombia's Pacific coast. Therefore, this study aimed to identify and characterize the genomes of Vibrio isolates obtained from A. tuberculosa. Bacterial isolates were obtained from 14 A. tuberculosa specimens collected from two locations along the Colombian Pacific coast, of which 17 strains were identified as Vibrio: V. parahaemolyticus (n = 12), V. alginolyticus (n = 3), V. fluvialis (n = 1), and V. natriegens (n = 1). Whole genome sequence of these isolates was done using Oxford Nanopore Technologies (ONT). The analysis revealed the presence of genes conferring resistance to β-lactams, tetracyclines, chloramphenicol, and macrolides, indicating potential resistance to these antimicrobial agents. Genes associated with virulence were also found, suggesting the potential pathogenicity of these Vibrio isolates, as well as genes for Type III Secretion Systems (T3SS) and Type VI Secretion Systems (T6SS), which play crucial roles in delivering virulence factors and in interbacterial competition. This study represents the first genomic analysis of bacteria within A. tuberculosa, shedding light on Vibrio genetic factors and contributing to a comprehensive understanding of the pathogenic potential of these Vibrio isolates.IMPORTANCEThis study presents the first comprehensive report on the whole genome analysis of Vibrio isolates obtained from Anadara tuberculosa, a bivalve species of great significance for social and economic matters on the Pacific coast of Colombia. Research findings have significant implications for the field, as they provide crucial information on the genetic factors and possible pathogenicity of Vibrio isolates associated with A. tuberculosa. The identification of antimicrobial resistance genes and virulence factors within these isolates emphasizes the potential risks they pose to both human and animal health. Furthermore, the presence of genes associated with Type III and Type VI Secretion Systems suggests their critical role in virulence and interbacterial competition. Understanding the genetic factors that contribute to Vibrio bacterial virulence and survival strategies within their ecological niche is of utmost importance for the effective prevention and management of diseases in aquaculture practices.
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Affiliation(s)
- Mariana Restrepo-Benavides
- Applied Genomics Research Group, Vicerrectoría de Investigación y Creación, Universidad de los Andes, Bogotá, Colombia
- Unit of Microbiology, Department of Basic Health Sciences, Faculty of Medicine and Health Sciences, IISPV, University Rovira i Virgili, Reus, Spain
| | - Daniela Lozano-Arce
- Applied Genomics Research Group, Vicerrectoría de Investigación y Creación, Universidad de los Andes, Bogotá, Colombia
| | - Laura Natalia Gonzalez-Garcia
- Applied Genomics Research Group, Vicerrectoría de Investigación y Creación, Universidad de los Andes, Bogotá, Colombia
- Systems and Computing Engineering Department, Universidad de Los Andes, Bogotá, Colombia
- UMR DIADE, Institut de Recherche pour le Développement, Université de Montpellier, Montpellier, France
| | - Felipe Báez-Aguirre
- Applied Genomics Research Group, Vicerrectoría de Investigación y Creación, Universidad de los Andes, Bogotá, Colombia
| | - Gabriela Ariza-Aranguren
- Applied Genomics Research Group, Vicerrectoría de Investigación y Creación, Universidad de los Andes, Bogotá, Colombia
| | - Daniel Faccini
- Applied Genomics Research Group, Vicerrectoría de Investigación y Creación, Universidad de los Andes, Bogotá, Colombia
| | | | - Pedro Jiménez
- Laboratorio de Fitopatología, Facultad de Ciencias Básicas y Aplicadas, Universidad Militar Nueva Granada, Cajicá, Colombia
| | - Ana Fernández-Bravo
- Unit of Microbiology, Department of Basic Health Sciences, Faculty of Medicine and Health Sciences, IISPV, University Rovira i Virgili, Reus, Spain
| | - Silvia Restrepo
- Departamento de Ingeniería Química y de Alimentos, Laboratorio de Micología y Fitopatología, Universidad de los Andes, Bogotá, Colombia
| | - Marcela Guevara-Suarez
- Applied Genomics Research Group, Vicerrectoría de Investigación y Creación, Universidad de los Andes, Bogotá, Colombia
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3
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Liu Y, Hou S. Bacteria manipulate host cells with channel-forming effectors. Trends Microbiol 2024; 32:8-9. [PMID: 37953153 DOI: 10.1016/j.tim.2023.10.013] [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: 10/24/2023] [Revised: 10/30/2023] [Accepted: 10/31/2023] [Indexed: 11/14/2023]
Abstract
Bacterial pathogens deliver effectors into host cells mostly to manipulate signaling and metabolic molecules, thereby subverting host immunity. A recent study by Nomura et al. demonstrates that certain effectors create membrane channels in host cells, enabling bacteria to access water and solutes for multiplication.
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Affiliation(s)
- Yukun Liu
- College of Forestry, Southwest Forestry University, 300 Bailong Si, Kunming, Yunnan 650224, China.
| | - Shuguo Hou
- Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Weifang, Shandong 261325, China.
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4
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Taya T, Teruyama F, Gojo S. Host-directed therapy for bacterial infections -Modulation of the phagolysosome pathway. Front Immunol 2023; 14:1227467. [PMID: 37841276 PMCID: PMC10570837 DOI: 10.3389/fimmu.2023.1227467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 09/11/2023] [Indexed: 10/17/2023] Open
Abstract
Bacterial infections still impose a significant burden on humanity, even though antimicrobial agents have long since been developed. In addition to individual severe infections, the f fatality rate of sepsis remains high, and the threat of antimicrobial-resistant bacteria grows with time, putting us at inferiority. Although tremendous resources have been devoted to the development of antimicrobial agents, we have yet to recover from the lost ground we have been driven into. Looking back at the evolution of treatment for cancer, which, like infectious diseases, has the similarity that host immunity eliminates the lesion, the development of drugs to eliminate the tumor itself has shifted from a single-minded focus on drug development to the establishment of a treatment strategy in which the de-suppression of host immunity is another pillar of treatment. In infectious diseases, on the other hand, the development of therapies that strengthen and support the immune system has only just begun. Among innate immunity, the first line of defense that bacteria encounter after invading the host, the molecular mechanisms of the phagolysosome pathway, which begins with phagocytosis to fusion with lysosome, have been elucidated in detail. Bacteria have a large number of strategies to escape and survive the pathway. Although the full picture is still unfathomable, the molecular mechanisms have been elucidated for some of them, providing sufficient clues for intervention. In this article, we review the host defense mechanisms and bacterial evasion mechanisms and discuss the possibility of host-directed therapy for bacterial infection by intervening in the phagolysosome pathway.
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Affiliation(s)
- Toshihiko Taya
- Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Fumiya Teruyama
- Pharmacology Research Department, Tokyo New Drug Research Laboratories, Kowa Company, Ltd., Tokyo, Japan
- Department of Regenerative Medicine, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Satoshi Gojo
- Department of Regenerative Medicine, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan
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Yadav GP, Wang H, Ouwendijk J, Cross S, Wang Q, Qin F, Verkade P, Zhu MX, Jiang QX. Chromogranin B (CHGB) is dimorphic and responsible for dominant anion channels delivered to cell surface via regulated secretion. Front Mol Neurosci 2023; 16:1205516. [PMID: 37435575 PMCID: PMC10330821 DOI: 10.3389/fnmol.2023.1205516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 05/26/2023] [Indexed: 07/13/2023] Open
Abstract
Regulated secretion is conserved in all eukaryotes. In vertebrates granin family proteins function in all key steps of regulated secretion. Phase separation and amyloid-based storage of proteins and small molecules in secretory granules require ion homeostasis to maintain their steady states, and thus need ion conductances in granule membranes. But granular ion channels are still elusive. Here we show that granule exocytosis in neuroendocrine cells delivers to cell surface dominant anion channels, to which chromogranin B (CHGB) is critical. Biochemical fractionation shows that native CHGB distributes nearly equally in soluble and membrane-bound forms, and both reconstitute highly selective anion channels in membrane. Confocal imaging resolves granular membrane components including proton pumps and CHGB in puncta on the cell surface after stimulated exocytosis. High pressure freezing immuno-EM reveals a major fraction of CHGB at granule membranes in rat pancreatic β-cells. A cryo-EM structure of bCHGB dimer of a nominal 3.5 Å resolution delineates a central pore with end openings, physically sufficient for membrane-spanning and large single channel conductance. Together our data support that CHGB-containing (CHGB+) channels are characteristic of regulated secretion, and function in granule ion homeostasis near the plasma membrane or possibly in other intracellular processes.
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Affiliation(s)
- Gaya P. Yadav
- Departments of Microbiology and Cell Science and of Medicinal Chemistry, University of Florida, Gainesville, FL, United States
- Departments of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, United States
- Laboratory of Molecular Physiology and Biophysics, Hauptman-Woodward Medical Research Institute, Buffalo, NY, United States
| | - Haiyuan Wang
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Joke Ouwendijk
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Stephen Cross
- Wolfson Bioimaging facility, University of Bristol, Bristol, United Kingdom
| | - Qiaochu Wang
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Feng Qin
- Departments of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, United States
| | - Paul Verkade
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Michael X. Zhu
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Qiu-Xing Jiang
- Departments of Microbiology and Cell Science and of Medicinal Chemistry, University of Florida, Gainesville, FL, United States
- Departments of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, United States
- Laboratory of Molecular Physiology and Biophysics, Hauptman-Woodward Medical Research Institute, Buffalo, NY, United States
- Cryo-EM Center, Laoshan Laboratory, Qingdao, Shandong, China
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6
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Meng Y, Mu L, Li Y, Yu M, Liu H, Pan Y, Zhao Y. Expression patterns and influence of the two-component system in Vibrio parahaemolyticus of different genotypes. Gene 2023; 859:147187. [PMID: 36627093 DOI: 10.1016/j.gene.2023.147187] [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: 10/12/2022] [Revised: 12/14/2022] [Accepted: 01/05/2023] [Indexed: 01/09/2023]
Abstract
Vibrio parahaemolyticus is a foodborne pathogen that threatens global food security and human health. The two-component system (TCS) is a primary method for bacteria self-regulate and adapt to the environment. Previous studies have shown that V. parahaemolyticus has four hemolytic genotypes with diverse biological phenotypes and environmental adaptability, but the mechanism is unclear. In this study, we investigated TCS expression patterns in V. parahaemolyticus with different genotypes for the first time and explored the differences in TCS between strains. The results showed similarities in the TCS expression pattern between VPC17 (tdh+/trh-) and VPC44 (tdh-/trh-), while VPC85(tdh-/trh+) had the least similar TCS expression pattern to the other three strains. Analysis of biological information revealed that different regulations of C4 dicarboxylate transport, tetrathionate uptake, antibiotic resistance, and flagellar synthesis involved in the TCS might influence strains' growth, antibiotic resistance, biofilm, and virulence. The different TCS regulatory abilities of strains might be one of the reasons for diverse biological characteristics and different environmental adaptations. This work provides a theoretical basis and a new research direction for the strain variability of V. parahaemolyticus.
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Affiliation(s)
- Yuanyuan Meng
- College of Food Science and Technology, Shanghai Ocean University, 999#, Hu Cheng Huan Road, Shanghai 201306, China
| | - Lili Mu
- College of Food Science and Technology, Shanghai Ocean University, 999#, Hu Cheng Huan Road, Shanghai 201306, China
| | - Yinhui Li
- College of Food Science and Technology, Shanghai Ocean University, 999#, Hu Cheng Huan Road, Shanghai 201306, China
| | - Man Yu
- College of Food Science and Technology, Shanghai Ocean University, 999#, Hu Cheng Huan Road, Shanghai 201306, China
| | - Haiquan Liu
- College of Food Science and Technology, Shanghai Ocean University, 999#, Hu Cheng Huan Road, Shanghai 201306, China; Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Storage and Preservation, Ministry of Agriculture and Rural Affairs, 999#, Hu Cheng Huan Road, Shanghai 201306, China; Shanghai Engineering Research Center of Aquatic-Product Processing & Preservation, 999#, Hu Cheng Huan Road, Shanghai 201306, China; Engineering Research Center of Food Thermal-processing Technology, 999#, Hu Cheng Huan Road, Shanghai 201306, China; Food Industry Chain Ecological Recycling Research Institute of Food Science and Technology College, 999#, Hu Cheng Huan Road, Shanghai 201306, China
| | - Yingjie Pan
- College of Food Science and Technology, Shanghai Ocean University, 999#, Hu Cheng Huan Road, Shanghai 201306, China; Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Storage and Preservation, Ministry of Agriculture and Rural Affairs, 999#, Hu Cheng Huan Road, Shanghai 201306, China; Shanghai Engineering Research Center of Aquatic-Product Processing & Preservation, 999#, Hu Cheng Huan Road, Shanghai 201306, China
| | - Yong Zhao
- College of Food Science and Technology, Shanghai Ocean University, 999#, Hu Cheng Huan Road, Shanghai 201306, China; Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Storage and Preservation, Ministry of Agriculture and Rural Affairs, 999#, Hu Cheng Huan Road, Shanghai 201306, China; Shanghai Engineering Research Center of Aquatic-Product Processing & Preservation, 999#, Hu Cheng Huan Road, Shanghai 201306, China.
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7
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Godlee C, Holden DW. Transmembrane substrates of type three secretion system injectisomes. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001292. [PMID: 36748571 PMCID: PMC9993115 DOI: 10.1099/mic.0.001292] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The type three secretion system injectisome of Gram-negative bacterial pathogens injects virulence proteins, called effectors, into host cells. Effectors of mammalian pathogens carry out a range of functions enabling bacterial invasion, replication, immune suppression and transmission. The injectisome secretes two translocon proteins that insert into host cell membranes to form a translocon pore, through which effectors are delivered. A subset of effectors also integrate into infected cell membranes, enabling a unique range of biochemical functions. Both translocon proteins and transmembrane effectors avoid cytoplasmic aggregation and integration into the bacterial inner membrane. Translocated transmembrane effectors locate and integrate into the appropriate host membrane. In this review, we focus on transmembrane translocon proteins and effectors of bacterial pathogens of mammals. We discuss what is known about the mechanisms underlying their membrane integration, as well as the functions conferred by the position of injectisome effectors within membranes.
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Affiliation(s)
- Camilla Godlee
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, London SW7 2AZ, UK
- Present address: Department of Infectious Diseases, School of Immunology and Microbial Sciences, King's College London, London, UK
- *Correspondence: Camilla Godlee, ;
| | - David W. Holden
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, London SW7 2AZ, UK
- *Correspondence: David W. Holden,
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8
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Ulhuq FR, Mariano G. Bacterial pore-forming toxins. MICROBIOLOGY (READING, ENGLAND) 2022; 168:001154. [PMID: 35333704 PMCID: PMC9558359 DOI: 10.1099/mic.0.001154] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 02/03/2022] [Indexed: 12/11/2022]
Abstract
Pore-forming toxins (PFTs) are widely distributed in both Gram-negative and Gram-positive bacteria. PFTs can act as virulence factors that bacteria utilise in dissemination and host colonisation or, alternatively, they can be employed to compete with rival microbes in polymicrobial niches. PFTs transition from a soluble form to become membrane-embedded by undergoing large conformational changes. Once inserted, they perforate the membrane, causing uncontrolled efflux of ions and/or nutrients and dissipating the protonmotive force (PMF). In some instances, target cells intoxicated by PFTs display additional effects as part of the cellular response to pore formation. Significant progress has been made in the mechanistic description of pore formation for the different PFTs families, but in several cases a complete understanding of pore structure remains lacking. PFTs have evolved recognition mechanisms to bind specific receptors that define their host tropism, although this can be remarkably diverse even within the same family. Here we summarise the salient features of PFTs and highlight where additional research is necessary to fully understand the mechanism of pore formation by members of this diverse group of protein toxins.
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Affiliation(s)
- Fatima R. Ulhuq
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Giuseppina Mariano
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
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Rahmatelahi H, El-Matbouli M, Menanteau-Ledouble S. Delivering the pain: an overview of the type III secretion system with special consideration for aquatic pathogens. Vet Res 2021; 52:146. [PMID: 34924019 PMCID: PMC8684695 DOI: 10.1186/s13567-021-01015-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 11/08/2021] [Indexed: 11/10/2022] Open
Abstract
Gram-negative bacteria are known to subvert eukaryotic cell physiological mechanisms using a wide array of virulence factors, among which the type three-secretion system (T3SS) is often one of the most important. The T3SS constitutes a needle-like apparatus that the bacterium uses to inject a diverse set of effector proteins directly into the cytoplasm of the host cells where they can hamper the host cellular machinery for a variety of purposes. While the structure of the T3SS is somewhat conserved and well described, effector proteins are much more diverse and specific for each pathogen. The T3SS can remodel the cytoskeleton integrity to promote intracellular invasion, as well as silence specific eukaryotic cell signals, notably to hinder or elude the immune response and cause apoptosis. This is also the case in aquatic bacterial pathogens where the T3SS can often play a central role in the establishment of disease, although it remains understudied in several species of important fish pathogens, notably in Yersinia ruckeri. In the present review, we summarise what is known of the T3SS, with a special focus on aquatic pathogens and suggest some possible avenues for research including the potential to target the T3SS for the development of new anti-virulence drugs.
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Affiliation(s)
- Hadis Rahmatelahi
- Clinical Division of Fish Medicine, University of Veterinary Medicine, 1210, Vienna, Austria
| | - Mansour El-Matbouli
- Clinical Division of Fish Medicine, University of Veterinary Medicine, 1210, Vienna, Austria
| | - Simon Menanteau-Ledouble
- Clinical Division of Fish Medicine, University of Veterinary Medicine, 1210, Vienna, Austria.
- Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg Ø, Denmark.
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10
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Targeting lysosomes in human disease: from basic research to clinical applications. Signal Transduct Target Ther 2021; 6:379. [PMID: 34744168 PMCID: PMC8572923 DOI: 10.1038/s41392-021-00778-y] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/26/2021] [Indexed: 01/18/2023] Open
Abstract
In recent years, accumulating evidence has elucidated the role of lysosomes in dynamically regulating cellular and organismal homeostasis. Lysosomal changes and dysfunction have been correlated with the development of numerous diseases. In this review, we interpreted the key biological functions of lysosomes in four areas: cellular metabolism, cell proliferation and differentiation, immunity, and cell death. More importantly, we actively sought to determine the characteristic changes and dysfunction of lysosomes in cells affected by these diseases, the causes of these changes and dysfunction, and their significance to the development and treatment of human disease. Furthermore, we outlined currently available targeting strategies: (1) targeting lysosomal acidification; (2) targeting lysosomal cathepsins; (3) targeting lysosomal membrane permeability and integrity; (4) targeting lysosomal calcium signaling; (5) targeting mTOR signaling; and (6) emerging potential targeting strategies. Moreover, we systematically summarized the corresponding drugs and their application in clinical trials. By integrating basic research with clinical findings, we discussed the current opportunities and challenges of targeting lysosomes in human disease.
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11
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Pazhani GP, Chowdhury G, Ramamurthy T. Adaptations of Vibrio parahaemolyticus to Stress During Environmental Survival, Host Colonization, and Infection. Front Microbiol 2021; 12:737299. [PMID: 34690978 PMCID: PMC8530187 DOI: 10.3389/fmicb.2021.737299] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 09/08/2021] [Indexed: 02/03/2023] Open
Abstract
Vibrio parahaemolyticus (Vp) is an aquatic Gram-negative bacterium that may infect humans and cause gastroenteritis and wound infections. The first pandemic of Vp associated infection was caused by the serovar O3:K6 and epidemics caused by the other serovars are increasingly reported. The two major virulence factors, thermostable direct hemolysin (TDH) and/or TDH-related hemolysin (TRH), are associated with hemolysis and cytotoxicity. Vp strains lacking tdh and/or trh are avirulent and able to colonize in the human gut and cause infection using other unknown factors. This pathogen is well adapted to survive in the environment and human host using several genetic mechanisms. The presence of prophages in Vp contributes to the emergence of pathogenic strains from the marine environment. Vp has two putative type-III and type-VI secretion systems (T3SS and T6SS, respectively) located on both the chromosomes. T3SS play a crucial role during the infection process by causing cytotoxicity and enterotoxicity. T6SS contribute to adhesion, virulence associated with interbacterial competition in the gut milieu. Due to differential expression, type III secretion system 2 (encoded on chromosome-2, T3SS2) and other genes are activated and transcribed by interaction with bile salts within the host. Chromosome-1 encoded T6SS1 has been predominantly identified in clinical isolates. Acquisition of genomic islands by horizontal gene transfer provides enhanced tolerance of Vp toward several antibiotics and heavy metals. Vp consists of evolutionarily conserved targets of GTPases and kinases. Expression of these genes is responsible for the survival of Vp in the host and biochemical changes during its survival. Advanced genomic analysis has revealed that various genes are encoded in Vp pathogenicity island that control and expression of virulence in the host. In the environment, the biofilm gene expression has been positively correlated to tolerance toward aerobic, anaerobic, and micro-aerobic conditions. The genetic similarity analysis of toxin/antitoxin systems of Escherichia coli with VP genome has shown a function that could induce a viable non-culturable state by preventing cell division. A better interpretation of the Vp virulence and other mechanisms that support its environmental fitness are important for diagnosis, treatment, prevention and spread of infections. This review identifies some of the common regulatory pathways of Vp in response to different stresses that influence its survival, gut colonization and virulence.
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Affiliation(s)
- Gururaja Perumal Pazhani
- School of Pharmaceutical Sciences, Chettinad Academy of Research and Education, Kelambakkam, India
| | - Goutam Chowdhury
- ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
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12
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Morot A, El Fekih S, Bidault A, Le Ferrand A, Jouault A, Kavousi J, Bazire A, Pichereau V, Dufour A, Paillard C, Delavat F. Virulence of Vibrio harveyi ORM4 towards the European abalone Haliotis tuberculata involves both quorum sensing and a type III secretion system. Environ Microbiol 2021; 23:5273-5288. [PMID: 33989448 DOI: 10.1111/1462-2920.15592] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/15/2021] [Accepted: 05/08/2021] [Indexed: 02/05/2023]
Abstract
Environmental Vibrio strains represent a major threat in aquaculture, but the understanding of their virulence mechanisms heavily relies on the transposition of knowledge from human-pathogen vibrios. Here, the genetic bases of the virulence of Vibrio harveyi ORM4 towards the European abalone Haliotis tuberculata were characterized. We demonstrated that luxO, encoding a major regulator of the quorum sensing system, is crucial for the virulence of this strain, and that its deletion leads to a decrease in swimming motility, biofilm formation, and exopolysaccharide production. Furthermore, the biofilm formation by V. harveyi ORM4 was increased by abalone serum, which required LuxO. The absence of LuxO in V. harveyi ORM4 yielded opposite phenotypes compared with other Vibrio species including V. campbellii (still frequently named V. harveyi). In addition, we report a full type III secretion system (T3SS) gene cluster in the V. harveyi ORM4 genome. LuxO was shown to negatively regulate the promoter activity of exsA, encoding the major regulator of the T3SS genes, and the deletion of exsA abolished the virulence of V. harveyi ORM4. These results unveil virulence mechanisms set up by this environmentally important bacterial pathogen and pave the way for a better molecular understanding of the regulation of its pathogenicity.
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Affiliation(s)
- Amandine Morot
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, Plouzané, France
- Université de Bretagne-Sud, EA 3884, LBCM, IUEM, Lorient, France
| | | | | | | | - Albane Jouault
- Université de Bretagne-Sud, EA 3884, LBCM, IUEM, Lorient, France
| | - Javid Kavousi
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, Plouzané, France
| | - Alexis Bazire
- Université de Bretagne-Sud, EA 3884, LBCM, IUEM, Lorient, France
| | | | - Alain Dufour
- Université de Bretagne-Sud, EA 3884, LBCM, IUEM, Lorient, France
| | | | - François Delavat
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, Plouzané, France
- UMR CNRS 6286 UFIP, University of Nantes, Nantes, France
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13
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Lian L, Xue J, Li W, Ren J, Tang F, Liu Y, Xue F, Dai J. VscF in T3SS1 Helps to Translocate VPA0226 in Vibrio parahaemolyticus. Front Cell Infect Microbiol 2021; 11:652432. [PMID: 33869083 PMCID: PMC8047418 DOI: 10.3389/fcimb.2021.652432] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 03/15/2021] [Indexed: 12/16/2022] Open
Abstract
In Vibrio parahaemolyticus, type III secretion system 1 (T3SS1) is a major virulence factor that delivers effectors into the host eukaryotic cytoplasm; however, studies on its infection mechanism are currently limited. To determine the function of the vscF gene, we constructed the vscF deletion mutant ΔvscF and complementation strain CΔvscF. Compared with those of wild-type POR-1 and CΔvscF, the cytotoxic, adherent, and apoptotic abilities of ΔvscF in HeLa cells were significantly reduced (P < 0.01). Furthermore, in infected HeLa cells, the mutant strain reduced the translocation rates of VP1683 and VP1686 effectors compared to the wild-type and complementation strains. A BLAST search showed that vscF is homologous to the MixH needle protein of Shigella flexneri, indicating that the vscF gene encodes the needle protein of T3SS1 in V. parahaemolyticus. Additional translocation assays showed that VPA0226 translocated into the HeLa eukaryotic cytoplasm via T3SS1, secretion assays showed that VPA0226 can be secreted to supernatant by T3SS1, indicating that VPA0226 belongs to the unpublished class of T3SS1 effectors. In conclusion, our data indicate an essential role of vscF in V. parahaemolyticus T3SS1 and revealed that VPA0226 can be secreted into the host cell cytoplasm via T3SS1. This study provides insights into a previously unexplored aspect of T3SS1, which is expected to contribute to the understanding of its infection mechanism.
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Affiliation(s)
- Lele Lian
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Jiao Xue
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Wanjun Li
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Jianluan Ren
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Fang Tang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Yongjie Liu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Feng Xue
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Jianjun Dai
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
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14
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Matsuda S. [Mechanisms of action of Vibrio parahaemoltyicus cytotoxins]. Nihon Saikingaku Zasshi 2021; 75:215-225. [PMID: 33390409 DOI: 10.3412/jsb.75.215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Vibrio parahaemolyticus, one of the Gram-negative common enteric pathogens, was first isolated in Japan in 1950. Since its discovery, this bacterium has been a major cause of food-poisoning in Japan, and its infection has recently undergone a global expansion. V. parahaemolyticus possesses a classical exotoxin, thermostable direct hemolysin, and two sets of type III secretion systems (T3SSs) that are able to inject effectors directly into host cells, which are its key virulence factors. Exotoxin/effector is exploited by many Gram-negative pathogens, and plays critical roles in pathogenesis by damaging host cells or by modulating host cell functions, through its activity on/in host cells. In recent years, functional activities of T3SS effectors produced by V. parahaemolyticus have been extensively studied, which has substantially increased our understanding of the pathogenic mechanisms of the bacterium. In paricular, some T3SS effectors of V. parahaemolyticus act as cytotoxins and thereby damage host cells. Here, I focus on these cytotoxic effectors of V. parahaemolyticus and describe recent advances in our understanding of their mechanisms of action.
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Affiliation(s)
- Shigeaki Matsuda
- Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University
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15
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Chimalapati S, de Souza Santos M, Lafrance AE, Ray A, Lee WR, Rivera-Cancel G, Vale G, Pawlowski K, Mitsche MA, McDonald JG, Liou J, Orth K. Vibrio deploys type 2 secreted lipase to esterify cholesterol with host fatty acids and mediate cell egress. eLife 2020; 9:58057. [PMID: 32808593 PMCID: PMC7434443 DOI: 10.7554/elife.58057] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 07/28/2020] [Indexed: 12/23/2022] Open
Abstract
Pathogens find diverse niches for survival including inside a host cell where replication occurs in a relatively protective environment. Vibrio parahaemolyticus is a facultative intracellular pathogen that uses its type 3 secretion system 2 (T3SS2) to invade and replicate inside host cells. Analysis of the T3SS2 pathogenicity island encoding the T3SS2 appeared to lack a mechanism for egress of this bacterium from the invaded host cell. Using a combination of molecular tools, we found that VPA0226, a constitutively secreted lipase, is required for escape of V. parahaemolyticus from the host cells. This lipase must be delivered into the host cytoplasm where it preferentially uses fatty acids associated with innate immune response to esterify cholesterol, weakening the plasma membrane and allowing egress of the bacteria. This study reveals the resourcefulness of microbes and the interplay between virulence systems and host cell resources to evolve an ingenious scheme for survival and escape.
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Affiliation(s)
- Suneeta Chimalapati
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, United States
| | - Marcela de Souza Santos
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Alexander E Lafrance
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Ann Ray
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Wan-Ru Lee
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Giomar Rivera-Cancel
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
| | - Gonçalo Vale
- Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, United States
| | - Krzysztof Pawlowski
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States.,Faculty of Agriculture and Biology, Warsaw University of Life Sciences, Warsaw, Poland
| | - Matthew A Mitsche
- Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, United States
| | - Jeffrey G McDonald
- Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, United States
| | - Jen Liou
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Kim Orth
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, United States
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16
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A membrane-depolarizing toxin substrate of the Staphylococcus aureus type VII secretion system mediates intraspecies competition. Proc Natl Acad Sci U S A 2020; 117:20836-20847. [PMID: 32769205 PMCID: PMC7456083 DOI: 10.1073/pnas.2006110117] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The type VII protein secretion system (T7SS) is conserved across Staphylococcus aureus strains and plays important roles in virulence and interbacterial competition. To date, only one T7SS substrate protein, encoded in a subset of S. aureus genomes, has been functionally characterized. Here, using an unbiased proteomic approach, we identify TspA as a further T7SS substrate. TspA is encoded distantly from the T7SS gene cluster and is found across all S. aureus strains as well as in Listeria and Enterococci. Heterologous expression of TspA from S. aureus strain RN6390 indicates its C-terminal domain is toxic when targeted to the Escherichia coli periplasm and that it depolarizes the cytoplasmic membrane. The membrane-depolarizing activity is alleviated by coproduction of the membrane-bound TsaI immunity protein, which is encoded adjacent to tspA on the S. aureus chromosome. Using a zebrafish hindbrain ventricle infection model, we demonstrate that the T7SS of strain RN6390 promotes bacterial replication in vivo, and deletion of tspA leads to increased bacterial clearance. The toxin domain of TspA is highly polymorphic and S. aureus strains encode multiple tsaI homologs at the tspA locus, suggestive of additional roles in intraspecies competition. In agreement, we demonstrate TspA-dependent growth inhibition of RN6390 by strain COL in the zebrafish infection model that is alleviated by the presence of TsaI homologs.
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17
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Peng W, Casey AK, Fernandez J, Carpinone EM, Servage KA, Chen Z, Li Y, Tomchick DR, Starai VJ, Orth K. A distinct inhibitory mechanism of the V-ATPase by Vibrio VopQ revealed by cryo-EM. Nat Struct Mol Biol 2020; 27:589-597. [PMID: 32424347 DOI: 10.1038/s41594-020-0429-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 04/01/2020] [Indexed: 12/18/2022]
Abstract
The Vibrio parahaemolyticus T3SS effector VopQ targets host-cell V-ATPase, resulting in blockage of autophagic flux and neutralization of acidic compartments. Here, we report the cryo-EM structure of VopQ bound to the Vo subcomplex of the V-ATPase. VopQ inserts into membranes and forms an unconventional pore while binding directly to subunit c of the V-ATPase membrane-embedded subcomplex Vo. We show that VopQ arrests yeast growth in vivo by targeting the immature Vo subcomplex in the endoplasmic reticulum (ER), thus providing insight into the observation that VopQ kills cells in the absence of a functional V-ATPase. VopQ is a bacterial effector that has been discovered to inhibit a host-membrane megadalton complex by coincidentally binding its target, inserting into a membrane and disrupting membrane potential. Collectively, our results reveal a mechanism by which bacterial effectors modulate host cell biology and provide an invaluable tool for future studies on V-ATPase-mediated membrane fusion and autophagy.
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Affiliation(s)
- Wei Peng
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Amanda K Casey
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jessie Fernandez
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | - Kelly A Servage
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Zhe Chen
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yang Li
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Diana R Tomchick
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Vincent J Starai
- Department of Microbiology, University of Georgia, Athens, GA, USA
- Department of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - Kim Orth
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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18
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Type III Secretion Effector VopQ of Vibrio parahaemolyticus Modulates Central Carbon Metabolism in Epithelial Cells. mSphere 2020; 5:5/2/e00960-19. [PMID: 32188755 PMCID: PMC7082145 DOI: 10.1128/msphere.00960-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The metabolic response of host cells upon infection is pathogen specific, and infection-induced host metabolic reprogramming may have beneficial effects on the proliferation of pathogens. V. parahaemolyticus contains a range of virulence factors to manipulate host signaling pathways and metabolic processes. In this study, we identified that the T3SS1 VopQ effector rewrites host metabolism in conjunction with the inflammation and cell death processes. Understanding how VopQ reprograms host cell metabolism during the infection could help us to identify novel therapeutic strategies to enhance the survival of host cells during V. parahaemolyticus infection. Vibrio parahaemolyticus is a Gram-negative halophilic pathogen that frequently causes acute gastroenteritis and occasional wound infection. V. parahaemolyticus contains several virulence factors, including type III secretion systems (T3SSs) and thermostable direct hemolysin (TDH). In particular, T3SS1 is a potent cytotoxic inducer, and T3SS2 is essential for causing acute gastroenteritis. Although much is known about manipulation of host signaling transductions by the V. parahaemolyticus effector, little is known about the host metabolomic changes modulated by V. parahaemolyticus. To address this knowledge gap, we performed a metabolomic analysis of the epithelial cells during V. parahaemolyticus infection using capillary electrophoresis-time of flight mass spectrometry (CE-TOF/MS). Our results revealed significant metabolomic perturbations upon V. parahaemolyticus infection. Moreover, we identified that T3SS1’s VopQ effector was responsible for inducing the significant metabolic changes in the infected cells. The VopQ effector dramatically altered the host cell’s glycolytic, tricarboxylic acid cycle (TCA), and amino acid metabolisms. VopQ effector disrupted host cell redox homeostasis by depleting cellular glutathione and subsequently increasing the level of reactive oxygen species (ROS) production. IMPORTANCE The metabolic response of host cells upon infection is pathogen specific, and infection-induced host metabolic reprogramming may have beneficial effects on the proliferation of pathogens. V. parahaemolyticus contains a range of virulence factors to manipulate host signaling pathways and metabolic processes. In this study, we identified that the T3SS1 VopQ effector rewrites host metabolism in conjunction with the inflammation and cell death processes. Understanding how VopQ reprograms host cell metabolism during the infection could help us to identify novel therapeutic strategies to enhance the survival of host cells during V. parahaemolyticus infection.
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19
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Jiao Y, Sun J. Bacterial Manipulation of Autophagic Responses in Infection and Inflammation. Front Immunol 2019; 10:2821. [PMID: 31849988 PMCID: PMC6901625 DOI: 10.3389/fimmu.2019.02821] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 11/15/2019] [Indexed: 01/07/2023] Open
Abstract
Eukaryotes have cell-autonomous defenses against environmental stress and pathogens. Autophagy is one of the main cellular defenses against intracellular bacteria. In turn, bacteria employ diverse mechanisms to interfere with autophagy initiation and progression to avoid elimination and even to subvert autophagy for their benefit. This review aims to discuss recent findings regarding the autophagic responses regulated by bacterial effectors. Effectors manipulate autophagy at different stages by using versatile strategies, such as interfering with autophagy-initiating signaling, preventing the recognition of autophagy-involved proteins, subverting autophagy component homeostasis, manipulating the autophagy process, and impacting other biological processes. We describe the barriers for intracellular bacteria in host cells and highlight the role of autophagy in the host-microbial interactions. Understanding the mechanisms through which bacterial effectors manipulate host responses will provide new insights into therapeutic approaches for prevention and treatment of chronic inflammation and infectious diseases.
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Affiliation(s)
- Yang Jiao
- Division of Gastroenterology and Hepatology, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Jun Sun
- Division of Gastroenterology and Hepatology, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
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20
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Peng W, de Souza Santos M, Li Y, Tomchick DR, Orth K. High-resolution cryo-EM structures of the E. coli hemolysin ClyA oligomers. PLoS One 2019; 14:e0213423. [PMID: 31048915 PMCID: PMC6497250 DOI: 10.1371/journal.pone.0213423] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 04/08/2019] [Indexed: 11/29/2022] Open
Abstract
Pore-forming proteins (PFPs) represent a functionally important protein family, that are found in organisms from viruses to humans. As a major branch of PFPs, bacteria pore-forming toxins (PFTs) permeabilize membranes and usually cause the death of target cells. E. coli hemolysin ClyA is the first member with the pore complex structure solved among α-PFTs, employing α-helices as transmembrane elements. ClyA is proposed to form pores composed of various numbers of protomers. With high-resolution cryo-EM structures, we observe that ClyA pore complexes can exist as newly confirmed oligomers of a tridecamer and a tetradecamer, at estimated resolutions of 3.2 Å and 4.3 Å, respectively. The 2.8 Å cryo-EM structure of a dodecamer dramatically improves the existing structural model. Structural analysis indicates that protomers from distinct oligomers resemble each other and neighboring protomers adopt a conserved interaction mode. We also show a stabilized intermediate state of ClyA during the transition process from soluble monomers to pore complexes. Unexpectedly, even without the formation of mature pore complexes, ClyA can permeabilize membranes and allow leakage of particles less than ~400 Daltons. In addition, we are the first to show that ClyA forms pore complexes in the presence of cholesterol within artificial liposomes. These findings provide new mechanistic insights into the dynamic process of pore assembly for the prototypical α-PFT ClyA.
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Affiliation(s)
- Wei Peng
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States of America
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, United States of America
| | - Marcela de Souza Santos
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States of America
| | - Yang Li
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, United States of America
| | - Diana R Tomchick
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, United States of America
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, United States of America
| | - Kim Orth
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States of America
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, United States of America
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, United States of America
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21
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Bargen K, Scraba M, Krämer I, Ketterer M, Nehls C, Krokowski S, Repnik U, Wittlich M, Maaser A, Zapka P, Bunge M, Schlesinger M, Huth G, Klees A, Hansen P, Jeschke A, Bendas G, Utermöhlen O, Griffiths G, Gutsmann T, Wohlmann J, Haas A. Virulence‐associated protein A fromRhodococcus equiis an intercompartmental pH‐neutralising virulence factor. Cell Microbiol 2018; 21:e12958. [DOI: 10.1111/cmi.12958] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 08/17/2018] [Accepted: 09/04/2018] [Indexed: 12/26/2022]
Affiliation(s)
- Kristine Bargen
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Mirella Scraba
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Ina Krämer
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Maren Ketterer
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | | | - Sina Krokowski
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Urska Repnik
- Department of BiosciencesUniversity of Oslo Oslo Norway
| | - Michaela Wittlich
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Anna Maaser
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Pia Zapka
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Madeleine Bunge
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | | | - Gitta Huth
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Annette Klees
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Philipp Hansen
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Andreas Jeschke
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
| | - Gerd Bendas
- Pharmaceutical InstituteUniversity of Bonn Bonn Germany
| | - Olaf Utermöhlen
- Institute for Medical Microbiology, Immunology and Hygiene, University Medical Center, and Center for Molecular Medicine Köln, and German Center for Infection Research (DCIF) Cologne Germany
| | | | | | - Jens Wohlmann
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
- Department of BiosciencesUniversity of Oslo Oslo Norway
| | - Albert Haas
- Division of Biophysics, Cell Biology InstituteUniversity of Bonn Bonn Germany
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22
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Yadav GP, Zheng H, Yang Q, Douma LG, Bloom LB, Jiang QX. Secretory granule protein chromogranin B (CHGB) forms an anion channel in membranes. Life Sci Alliance 2018; 1:e201800139. [PMID: 30456382 PMCID: PMC6238609 DOI: 10.26508/lsa.201800139] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 08/29/2018] [Accepted: 09/11/2018] [Indexed: 12/14/2022] Open
Abstract
The CHGB subfamily of secretory granule proteins forms a new family of anion-selective channels by interacting with membranes via two amphipathic α-helices. The channel exhibits higher anion selectivity, larger conductance, higher DIDS-binding affinity, and higher Cl− sensitivity than other known anion channels. Regulated secretion is an intracellular pathway that is highly conserved from protists to humans. Granin family proteins were proposed to participate in the biogenesis, maturation and release of secretory granules in this pathway. However, the exact molecular mechanisms underlying the intracellular functions of the granin family proteins remain unclear. Here, we show that chromogranin B (CHGB), a secretory granule protein, inserts itself into membrane and forms a chloride-conducting channel. CHGB interacts strongly with phospholipid membranes through two amphipathic α helices. At a high local concentration, CHGB insertion in membrane causes significant bilayer remodeling, producing protein-coated nanoparticles and nanotubules. Fast kinetics and high cooperativity for anion efflux from CHGB vesicles suggest that CHGB tetramerizes to form a functional channel with a single-channel conductance of ∼125 pS (150/150 mM Cl−). The CHGB channel is sensitive to an anion channel blocker and exhibits higher anion selectivity than the other six known families of Cl− channels. Our data suggest that the CHGB subfamily of granin proteins forms a new family of organelle chloride channels.
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Affiliation(s)
- Gaya P Yadav
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA
| | - Hui Zheng
- Department of Physiology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Qing Yang
- Crop Designing Center, Henan Academy of Agricultural Sciences, Zhengzhou, PR China
| | - Lauren G Douma
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| | - Linda B Bloom
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| | - Qiu-Xing Jiang
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA
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23
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Affiliation(s)
- Carlos R Osorio
- a Departamento de Microbioloxía e Parasitoloxía , Instituto de Acuicultura, Universidade de Santiago de Compostela , Santiago de Compostela , Spain
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24
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Wen J, Fang F, Guo SH, Zhang Y, Peng XL, Sun WM, Wei XR, He JS, Hung T. Amyloid β-Derived Diffusible Ligands (ADDLs) Induce Abnormal Autophagy Associated with Aβ Aggregation Degree. J Mol Neurosci 2017; 64:162-174. [DOI: 10.1007/s12031-017-1015-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 12/03/2017] [Indexed: 11/25/2022]
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25
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Kissing S, Saftig P, Haas A. Vacuolar ATPase in phago(lyso)some biology. Int J Med Microbiol 2017; 308:58-67. [PMID: 28867521 DOI: 10.1016/j.ijmm.2017.08.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 07/28/2017] [Accepted: 08/23/2017] [Indexed: 12/23/2022] Open
Abstract
Many eukaryotic cells ingest extracellular particles in a process termed phagocytosis which entails the generation of a new intracellular compartment, the phagosome. Phagosomes change their composition over time and this maturation process culminates in their fusion with acidic, hydrolase-rich lysosomes. During the maturation process, degradation and, when applicable, killing of the cargo may ensue. Many of the events that are pathologically relevant depend on strong acidification of phagosomes by the 'vacuolar' ATPase (V-ATPase). This protein complex acidifies the lumen of some intracellular compartments at the expense of ATP hydrolysis. We discuss here the roles and importance of V-ATPase in intracellular trafficking, its distribution, inhibition and activities, its role in the defense against microorganisms and the counteractivities of pathogens.
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Affiliation(s)
- Sandra Kissing
- Institut für Biochemie, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany
| | - Paul Saftig
- Institut für Biochemie, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany.
| | - Albert Haas
- Institut für Zellbiologie, Friedrich-Wilhelms-Universität Bonn, Ulrich-Haberland-Str. 61A, D-53121 Bonn, Germany.
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Ghenem L, Elhadi N, Alzahrani F, Nishibuchi M. Vibrio Parahaemolyticus: A Review on Distribution, Pathogenesis, Virulence Determinants and Epidemiology. SAUDI JOURNAL OF MEDICINE & MEDICAL SCIENCES 2017; 5:93-103. [PMID: 30787765 PMCID: PMC6298368 DOI: 10.4103/sjmms.sjmms_30_17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Vibrio parahaemolyticus is a Gram-negative, halophilic bacterium isolated from marine environments globally. After the consumption of contaminated seafood, V. parahaemolyticus causes acute gastroenteritis. To initiate infection, a wide range of virulence factors are required. A complex group of genes is known to participate in the pathogenicity of V. parahaemolyticus; however, to understand the full mechanism of infection, extensive research is yet required. V. parahaemolyticus has become the leading cause of seafood-related gastroenteritis in Japan, the United States and several other parts of the world. In addition, outbreaks caused by the pandemic clone of this organism are escalating and spreading universally. To minimize the risk of V. parahaemolyticus infection and warrant the safety of seafood, collaboration between governments and scientists is required. We herein provide an updated review of the pathogenicity determinants and distribution of V. parahaemolyticus to deliver a better understanding of the significance of V. parahaemolyticus and its host-pathogen interactions.
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Affiliation(s)
- Lubna Ghenem
- Department of Clinical Laboratory Science, College of Applied Medical Sciences, University of Dammam, 31441 Dammam, Kingdom of Saudi Arabia
| | - Nasreldin Elhadi
- Department of Clinical Laboratory Science, College of Applied Medical Sciences, University of Dammam, 31441 Dammam, Kingdom of Saudi Arabia
| | - Faisal Alzahrani
- Department of Clinical Laboratory Science, College of Applied Medical Sciences, University of Dammam, 31441 Dammam, Kingdom of Saudi Arabia
| | - Mitsuaki Nishibuchi
- Center for Southeast Asian Studies, Kyoto University, 46 Shomoadachi-cho, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
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Abstract
Bacterial pathogens encode a wide variety of effectors and toxins that hijack host cell structure and function. Of particular importance are virulence factors that target actin cytoskeleton dynamics critical for cell shape, stability, motility, phagocytosis, and division. In addition, many bacteria target organelles of the general secretory pathway (e.g., the endoplasmic reticulum and the Golgi complex) and recycling pathways (e.g., the endolysosomal system) to establish and maintain an intracellular replicative niche. Recent research on the biochemistry and structural biology of bacterial effector proteins and toxins has begun to shed light on the molecular underpinnings of these host-pathogen interactions. This exciting work is revealing how pathogens gain control of the complex and dynamic host cellular environments, which impacts our understanding of microbial infectious disease, immunology, and human cell biology.
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Affiliation(s)
- Alyssa Jimenez
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390;
| | - Didi Chen
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390;
| | - Neal M Alto
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390;
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Salomon D, Klimko JA, Trudgian DC, Kinch LN, Grishin NV, Mirzaei H, Orth K. Type VI Secretion System Toxins Horizontally Shared between Marine Bacteria. PLoS Pathog 2015; 11:e1005128. [PMID: 26305100 PMCID: PMC4549250 DOI: 10.1371/journal.ppat.1005128] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 08/04/2015] [Indexed: 11/19/2022] Open
Abstract
The type VI secretion system (T6SS) is a widespread protein secretion apparatus used by Gram-negative bacteria to deliver toxic effector proteins into adjacent bacterial or host cells. Here, we uncovered a role in interbacterial competition for the two T6SSs encoded by the marine pathogen Vibrio alginolyticus. Using comparative proteomics and genetics, we identified their effector repertoires. In addition to the previously described effector V12G01_02265, we identified three new effectors secreted by T6SS1, indicating that the T6SS1 secretes at least four antibacterial effectors, of which three are members of the MIX-effector class. We also showed that the T6SS2 secretes at least three antibacterial effectors. Our findings revealed that many MIX-effectors belonging to clan V are “orphan” effectors that neighbor mobile elements and are shared between marine bacteria via horizontal gene transfer. We demonstrated that a MIX V-effector from V. alginolyticus is a functional T6SS effector when ectopically expressed in another Vibrio species. We propose that mobile MIX V-effectors serve as an environmental reservoir of T6SS effectors that are shared and used to diversify antibacterial toxin repertoires in marine bacteria, resulting in enhanced competitive fitness. The bacterial type VI secretion system (T6SS) is a contact-dependent protein secretion apparatus that is emerging as a major component of interbacterial competition in the environment. The bacterium Vibrio alginolyticus is a pathogen of marine animals and a causal agent of wound infections, otitis, and gastroenteritis in humans. In this study, we provide a comprehensive characterization of the environmental regulation, antibacterial activities, and secreted effector repertoires of the two T6SSs found in this pathogen. We also identify a subset of T6SS effectors that appear to be mobile and shared between marine bacteria that can interact with each other in aquatic environments. Our findings suggest that bacteria can incorporate T6SS effectors from competitors in the environment. These newly acquired toxins may be used to expand and diversify T6SS effector repertoires and enhance bacterial fitness.
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Affiliation(s)
- Dor Salomon
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- * E-mail: (DS); (KO)
| | - John A. Klimko
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - David C. Trudgian
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Lisa N. Kinch
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Nick V. Grishin
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Hamid Mirzaei
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Kim Orth
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- * E-mail: (DS); (KO)
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Zhong L, Hu J, Shu W, Gao B, Xiong S. Epigallocatechin-3-gallate opposes HBV-induced incomplete autophagy by enhancing lysosomal acidification, which is unfavorable for HBV replication. Cell Death Dis 2015; 6:e1770. [PMID: 25996297 PMCID: PMC4669713 DOI: 10.1038/cddis.2015.136] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 04/15/2015] [Accepted: 04/16/2015] [Indexed: 02/06/2023]
Abstract
Epigallocatechin-3-gallate (EGCG), a major polyphenol in green tea, exhibits diverse beneficial properties, including antiviral activity. Autophagy is a cellular process that is involved in the degradation of long-lived proteins and damaged organelles. Recent evidence indicates that modulation of autophagy is a potential therapeutic strategy for various viral diseases. In the present study, we investigated the effect of EGCG on hepatitis B virus (HBV) replication and the possible involvement of autophagy in this process. Our results showed that HBV induced autophagosome formation, which was required for replication of itself. However, although EGCG efficiently inhibited HBV replication, it enhanced, but not inhibited, autophagosome formation in hepatoma cells. Further study showed that HBV induced an incomplete autophagy, while EGCG, similar to starvation, was able to induce a complete autophagic process, which appeared to be unfavorable for HBV replication. Furthermore, it was found that HBV induced an incomplete autophagy by impairing lysosomal acidification, while it lost this ability in the presence of EGCG. Taken together, these data demonstrated that EGCG treatment opposed HBV-induced incomplete autophagy via enhancing lysosomal acidification, which was unfavorable for HBV replication.
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Affiliation(s)
- L Zhong
- Institute for Immunobiology, Department of Immunology, Shanghai Medical College of Fudan University, Shanghai 200032, P.R. China
| | - J Hu
- Institute for Immunobiology, Department of Immunology, Shanghai Medical College of Fudan University, Shanghai 200032, P.R. China
| | - W Shu
- Institute for Immunobiology, Department of Immunology, Shanghai Medical College of Fudan University, Shanghai 200032, P.R. China
| | - B Gao
- Institute for Immunobiology, Department of Immunology, Shanghai Medical College of Fudan University, Shanghai 200032, P.R. China
| | - S Xiong
- Institute for Immunobiology, Department of Immunology, Shanghai Medical College of Fudan University, Shanghai 200032, P.R. China
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215006, P.R. China
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Wang R, Zhong Y, Gu X, Yuan J, Saeed AF, Wang S. The pathogenesis, detection, and prevention of Vibrio parahaemolyticus. Front Microbiol 2015; 6:144. [PMID: 25798132 PMCID: PMC4350439 DOI: 10.3389/fmicb.2015.00144] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 02/07/2015] [Indexed: 12/02/2022] Open
Abstract
Vibrio parahaemolyticus, a Gram-negative motile bacterium that inhabits marine and estuarine environments throughout the world, is a major food-borne pathogen that causes life-threatening diseases in humans after the consumption of raw or undercooked seafood. The global occurrence of V. parahaemolyticus accentuates the importance of investigating its virulence factors and their effects on the human host. This review describes the virulence factors of V. parahaemolyticus reported to date, including hemolysin, urease, two type III secretion systems and two type VI secretion systems, which both cause both cytotoxicity in cultured cells and enterotoxicity in animal models. We describe various types of detection methods, based on virulence factors, that are used for quantitative detection of V. parahaemolyticus in seafood. We also discuss some useful preventive measures and therapeutic strategies for the diseases mediated by V. parahaemolyticus, which can reduce, to some extent, the damage to humans and aquatic animals attributable to V. parahaemolyticus. This review extends our understanding of the pathogenic mechanisms of V. parahaemolyticus mediated by virulence factors and the diseases it causes in its human host. It should provide new insights for the diagnosis, treatment, and prevention of V. parahaemolyticus infection.
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Affiliation(s)
- Rongzhi Wang
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry and Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
| | - Yanfang Zhong
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry and Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
| | - Xiaosong Gu
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry and Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
| | - Jun Yuan
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry and Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
| | - Abdullah F Saeed
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry and Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
| | - Shihua Wang
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry and Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University Fuzhou, China
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31
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Sontag RL, Mihai C, Orr G, Savchenko A, Skarina T, Cui H, Cort JR, Adkins JN, Brown RN. Electroporation of functional bacterial effectors into mammalian cells. J Vis Exp 2015:52296. [PMID: 25650771 PMCID: PMC4331347 DOI: 10.3791/52296] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The study of protein interactions in the context of living cells can generate critical information about localization, dynamics, and interacting partners. This information is particularly valuable in the context of host-pathogen interactions. Many pathogen proteins function within host cells in a variety of way such as, enabling evasion of the host immune system and survival within the intracellular environment. To study these pathogen-protein host-cell interactions, several approaches are commonly used, including: in vivo infection with a strain expressing a tagged or mutant protein, or introduction of pathogen genes via transfection or transduction. Each of these approaches has advantages and disadvantages. We sought a means to directly introduce exogenous proteins into cells. Electroporation is commonly used to introduce nucleic acids into cells, but has been more rarely applied to proteins although the biophysical basis is exactly the same. A standard electroporator was used to introduce affinity-tagged bacterial effectors into mammalian cells. Human epithelial and mouse macrophage cells were cultured by traditional methods, detached, and placed in 0.4 cm gap electroporation cuvettes with an exogenous bacterial pathogen protein of interest (e.g. Salmonella Typhimurium GtgE). After electroporation (0.3 kV) and a short (4 hr) recovery period, intracellular protein was verified by fluorescently labeling the protein via its affinity tag and examining spatial and temporal distribution by confocal microscopy. The electroporated protein was also shown to be functional inside the cell and capable of correct subcellular trafficking and protein-protein interaction. While the exogenous proteins tended to accumulate on the surface of the cells, the electroporated samples had large increases in intracellular effector concentration relative to incubation alone. The protocol is simple and fast enough to be done in a parallel fashion, allowing for high-throughput characterization of pathogen proteins in host cells including subcellular targeting and function of virulence proteins.
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Affiliation(s)
- Ryan L Sontag
- Biological Sciences Division, Pacific Northwest National Laboratory
| | - Cosmin Mihai
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory
| | - Galya Orr
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory
| | - Alexei Savchenko
- Structural Proteomics Group, Ontario Center for Structural Proteomics, University of Toronto
| | - Tatiana Skarina
- Structural Proteomics Group, Ontario Center for Structural Proteomics, University of Toronto
| | - Hong Cui
- Structural Proteomics Group, Ontario Center for Structural Proteomics, University of Toronto
| | - John R Cort
- Biological Sciences Division, Pacific Northwest National Laboratory
| | - Joshua N Adkins
- Biological Sciences Division, Pacific Northwest National Laboratory;
| | - Roslyn N Brown
- Center for Bioproducts and Bioenergy, Washington State University;
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33
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Letchumanan V, Chan KG, Lee LH. Vibrio parahaemolyticus: a review on the pathogenesis, prevalence, and advance molecular identification techniques. Front Microbiol 2014; 5:705. [PMID: 25566219 PMCID: PMC4263241 DOI: 10.3389/fmicb.2014.00705] [Citation(s) in RCA: 280] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 11/27/2014] [Indexed: 12/13/2022] Open
Abstract
Vibrio parahaemolyticus is a Gram-negative halophilic bacterium that is found in estuarine, marine and coastal environments. V. parahaemolyticus is the leading causal agent of human acute gastroenteritis following the consumption of raw, undercooked, or mishandled marine products. In rare cases, V. parahaemolyticus causes wound infection, ear infection or septicaemia in individuals with pre-existing medical conditions. V. parahaemolyticus has two hemolysins virulence factors that are thermostable direct hemolysin (tdh)-a pore-forming protein that contributes to the invasiveness of the bacterium in humans, and TDH-related hemolysin (trh), which plays a similar role as tdh in the disease pathogenesis. In addition, the bacterium is also encodes for adhesions and type III secretion systems (T3SS1 and T3SS2) to ensure its survival in the environment. This review aims at discussing the V. parahaemolyticus growth and characteristics, pathogenesis, prevalence and advances in molecular identification techniques.
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Affiliation(s)
- Vengadesh Letchumanan
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Bandar Sunway, Malaysia ; Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya Kuala Lumpur, Malaysia
| | - Kok-Gan Chan
- Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya Kuala Lumpur, Malaysia
| | - Learn-Han Lee
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Bandar Sunway, Malaysia
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Vibrio effector protein VopQ inhibits fusion of V-ATPase-containing membranes. Proc Natl Acad Sci U S A 2014; 112:100-5. [PMID: 25453092 DOI: 10.1073/pnas.1413764111] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Vesicle fusion governs many important biological processes, and imbalances in the regulation of membrane fusion can lead to a variety of diseases such as diabetes and neurological disorders. Here we show that the Vibrio parahaemolyticus effector protein VopQ is a potent inhibitor of membrane fusion based on an in vitro yeast vacuole fusion model. Previously, we demonstrated that VopQ binds to the V(o) domain of the conserved V-type H(+)-ATPase (V-ATPase) found on acidic compartments such as the yeast vacuole. VopQ forms a nonspecific, voltage-gated membrane channel of 18 Å resulting in neutralization of these compartments. We now present data showing that VopQ inhibits yeast vacuole fusion. Furthermore, we identified a unique mutation in VopQ that delineates its two functions, deacidification and inhibition of membrane fusion. The use of VopQ as a membrane fusion inhibitor in this manner now provides convincing evidence that vacuole fusion occurs independently of luminal acidification in vitro.
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35
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Woolery AR, Yu X, LaBaer J, Orth K. AMPylation of Rho GTPases subverts multiple host signaling processes. J Biol Chem 2014; 289:32977-88. [PMID: 25301945 DOI: 10.1074/jbc.m114.601310] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Rho GTPases are frequent targets of virulence factors as they are keystone signaling molecules. Herein, we demonstrate that AMPylation of Rho GTPases by VopS is a multifaceted virulence mechanism that counters several host immunity strategies. Activation of NFκB, Erk, and JNK kinase signaling pathways were inhibited in a VopS-dependent manner during infection with Vibrio parahaemolyticus. Phosphorylation and degradation of IKBα were inhibited in the presence of VopS as was nuclear translocation of the NFκB subunit p65. AMPylation also prevented the generation of superoxide by the phagocytic NADPH oxidase complex, potentially by inhibiting the interaction of Rac and p67. Furthermore, the interaction of GTPases with the E3 ubiquitin ligases cIAP1 and XIAP was hindered, leading to decreased degradation of Rac and RhoA during infection. Finally, we screened for novel Rac1 interactions using a nucleic acid programmable protein array and discovered that Rac1 binds to the protein C1QA, a protein known to promote immune signaling in the cytosol. Interestingly, this interaction was disrupted by AMPylation. We conclude that AMPylation of Rho Family GTPases by VopS results in diverse inhibitory consequences during infection beyond the most obvious phenotype, the collapse of the actin cytoskeleton.
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Affiliation(s)
- Andrew R Woolery
- From the Department of Molecular Biology, UT Southwestern Medical Center, Dallas, Texas 75390-9148 and
| | - Xiaobo Yu
- The Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, Arizona 85287
| | - Joshua LaBaer
- The Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, Arizona 85287
| | - Kim Orth
- From the Department of Molecular Biology, UT Southwestern Medical Center, Dallas, Texas 75390-9148 and
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Lim J, Stones DH, Hawley CA, Watson CA, Krachler AM. Multivalent adhesion molecule 7 clusters act as signaling platform for host cellular GTPase activation and facilitate epithelial barrier dysfunction. PLoS Pathog 2014; 10:e1004421. [PMID: 25255250 PMCID: PMC4177989 DOI: 10.1371/journal.ppat.1004421] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 08/25/2014] [Indexed: 01/24/2023] Open
Abstract
Vibrio parahaemolyticus is an emerging bacterial pathogen which colonizes the gastrointestinal tract and can cause severe enteritis and bacteraemia. During infection, V. parahaemolyticus primarily attaches to the small intestine, where it causes extensive tissue damage and compromises epithelial barrier integrity. We have previously described that Multivalent Adhesion Molecule (MAM) 7 contributes to initial attachment of V. parahaemolyticus to epithelial cells. Here we show that the bacterial adhesin, through multivalent interactions between surface-induced adhesin clusters and phosphatidic acid lipids in the host cell membrane, induces activation of the small GTPase RhoA and actin rearrangements in host cells. In infection studies with V. parahaemolyticus we further demonstrate that adhesin-triggered activation of the ROCK/LIMK signaling axis is sufficient to redistribute tight junction proteins, leading to a loss of epithelial barrier function. Taken together, these findings show an unprecedented mechanism by which an adhesin acts as assembly platform for a host cellular signaling pathway, which ultimately facilitates breaching of the epithelial barrier by a bacterial pathogen. Vibrio parahaemolyticus is a bacterial pathogen which occurs in marine and estuarine environments. It is a main cause of gastrointestinal illness following the consumption of raw or undercooked seafood. In immunocompromised people, the bacteria can sometimes enter the bloodstream and cause septicemia, a serious and often fatal condition. V. parahaemolyticus attaches to host tissues using adhesive proteins. Multivalent Adhesion Molecule (MAM) 7 is an adhesin which helps the bacteria to hold onto the host cells early on during infection. It does so by binding two different molecules on the host, a protein (fibronectin) and phospholipids called phosphatidic acids. We show that MAM7 does not only play a role in sticking to host cells. By forming adhesin clusters on the host surface and binding to host lipids, it triggers signaling processes in the host. These include activation of RhoA, an important mediator of cytoskeletal dynamics. By doing so, MAM7 perturbs proteins at cellular junctions, which normally maintain the cells in the gut as a tightly sealed layer protective of environmental influences. When bacteria use MAM7 to attach to the intestine, the seals between cells break, permitting bacteria to cross the barrier and cause infection of underlying tissues.
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Affiliation(s)
- Jenson Lim
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Daniel H. Stones
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Catherine Alice Hawley
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Charlie Anne Watson
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Anne Marie Krachler
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
- * E-mail:
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37
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Effectors of animal and plant pathogens use a common domain to bind host phosphoinositides. Nat Commun 2014; 4:2973. [PMID: 24346350 DOI: 10.1038/ncomms3973] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 11/18/2013] [Indexed: 12/30/2022] Open
Abstract
Bacterial Type III Secretion Systems deliver effectors into host cells to manipulate cellular processes to the advantage of the pathogen. Many host targets of these effectors are found on membranes. Therefore, to identify their targets, effectors often use specialized membrane-localization domains to localize to appropriate host membranes. However, the molecular mechanisms used by many domains are unknown. Here we identify a conserved bacterial phosphoinositide-binding domain (BPD) that is found in functionally diverse Type III effectors of both plant and animal pathogens. We show that members of the BPD family functionally bind phosphoinositides and mediate localization to host membranes. Moreover, NMR studies reveal that the BPD of the newly identified Vibrio parahaemolyticus Type III effector VopR is unfolded in solution, but folds into a specific structure upon binding its ligand phosphatidylinositol-(4,5)-bisphosphate. Thus, our findings suggest a possible mechanism for promoting refolding of Type III effectors after delivery into host cells.
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Waddell B, Southward CM, McKenna N, DeVinney R. Identification of VPA0451 as the specific chaperone for theVibrio parahaemolyticuschromosome 1 type III-secreted effector VPA0450. FEMS Microbiol Lett 2014; 353:141-50. [DOI: 10.1111/1574-6968.12416] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 03/04/2014] [Indexed: 11/30/2022] Open
Affiliation(s)
- Barbara Waddell
- Department of Microbiology, Immunology and Infectious Diseases; Snyder Institute for Chronic Diseases; University of Calgary; Calgary AB Canada
| | - Carolyn M. Southward
- Department of Microbiology, Immunology and Infectious Diseases; Snyder Institute for Chronic Diseases; University of Calgary; Calgary AB Canada
| | - Neil McKenna
- Department of Microbiology, Immunology and Infectious Diseases; Snyder Institute for Chronic Diseases; University of Calgary; Calgary AB Canada
| | - Rebekah DeVinney
- Department of Microbiology, Immunology and Infectious Diseases; Snyder Institute for Chronic Diseases; University of Calgary; Calgary AB Canada
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Nydam SD, Shah DH, Call DR. Transcriptome analysis of Vibrio parahaemolyticus in type III secretion system 1 inducing conditions. Front Cell Infect Microbiol 2014; 4:1. [PMID: 24478989 PMCID: PMC3895804 DOI: 10.3389/fcimb.2014.00001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 01/02/2014] [Indexed: 12/16/2022] Open
Abstract
Vibrio parahaemolyticus is an emerging bacterial pathogen capable of causing inflammatory gastroenteritis, wound infections, and septicemia. As a food-borne illness, infection is most frequently associated with the consumption of raw or undercooked seafood, particularly shellfish. It is the primary cause of Vibrio-associated food-borne illness in the United States and the leading cause of food-borne illness in Japan. The larger of its two chromosomes harbors a set of genes encoding type III section system 1 (T3SS1), a virulence factor present in all V. parahaemolyticus strains that is similar to the Yersinia ysc T3SS. T3SS1 translocates effector proteins into eukaryotic cells where they induce changes to cellular physiology and modulate host-pathogen interactions. T3SS1 is also responsible for cytotoxicity toward several different cultured cell lines as well as mortality in a mouse model. Herein we used RNA-seq to obtain global transcriptome patterns of V. parahaemolyticus under conditions that either induce [growth in Dulbecco's Modified Eagle Medium (DMEM) media, in trans expression of transcriptional regulator exsA] or repress T3SS1 expression (growth in LB-S media, in trans exsD expression) and during infection of HeLa cells over time. Comparative transcriptomic analysis demonstrated notable differences in the expression patterns under inducing conditions and was also used to generate an expression profile of V. parahaemolyticus during infection of HeLa cells. In addition, we identified several new genes that are associated with T3SS1 expression and may warrant further study.
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Affiliation(s)
- Seth D Nydam
- Department of Veterinary Microbiology and Pathology, Washington State University Pullman, WA, USA ; Paul G. Allen School for Global Animal Health, Washington State University Pullman, WA, USA
| | - Devendra H Shah
- Department of Veterinary Microbiology and Pathology, Washington State University Pullman, WA, USA ; Paul G. Allen School for Global Animal Health, Washington State University Pullman, WA, USA
| | - Douglas R Call
- Department of Veterinary Microbiology and Pathology, Washington State University Pullman, WA, USA ; Paul G. Allen School for Global Animal Health, Washington State University Pullman, WA, USA
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O'Boyle N, Boyd A. Manipulation of intestinal epithelial cell function by the cell contact-dependent type III secretion systems of Vibrio parahaemolyticus. Front Cell Infect Microbiol 2014; 3:114. [PMID: 24455490 PMCID: PMC3887276 DOI: 10.3389/fcimb.2013.00114] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 12/21/2013] [Indexed: 12/23/2022] Open
Abstract
Vibrio parahaemolyticus elicits gastroenteritis by deploying Type III Secretion Systems (TTSS) to deliver effector proteins into epithelial cells of the human intestinal tract. The bacteria must adhere to the human cells to allow colonization and operation of the TTSS translocation apparatus bridging the bacterium and the host cell. This article first reviews recent advances in identifying the molecules responsible for intercellular adherence. V. parahaemolyticus possesses two TTSS, each of which delivers an exclusive set of effectors and mediates unique effects on the host cell. TTSS effectors primarily target and alter the activation status of host cell signaling proteins, thereby bringing about changes in the regulation of cellular behavior. TTSS1 is responsible for the cytotoxicity of V. parahaemolyticus, while TTSS2 is necessary for the enterotoxicity of the pathogen. Recent publications have elucidated the function of several TTSS effectors and their importance in the virulence of the bacterium. This review will explore the ability of the TTSS to manipulate activities of human intestinal cells and how this modification of cell function favors bacterial colonization and persistence of V. parahaemolyticus in the host.
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Affiliation(s)
- Nicky O'Boyle
- Pathogenic Mechanisms Research Group, Microbiology, School of Natural Sciences, National University of Ireland Galway Galway, Ireland
| | - Aoife Boyd
- Pathogenic Mechanisms Research Group, Microbiology, School of Natural Sciences, National University of Ireland Galway Galway, Ireland
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Zhu S, Kojima S, Homma M. Structure, gene regulation and environmental response of flagella in Vibrio. Front Microbiol 2013; 4:410. [PMID: 24400002 PMCID: PMC3872333 DOI: 10.3389/fmicb.2013.00410] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 12/12/2013] [Indexed: 01/15/2023] Open
Abstract
Vibrio species are Gram-negative, rod-shaped bacteria that live in aqueous environments. Several species, such as V. harveyi, V. alginotyticus, and V. splendidus, are associated with diseases in fish or shellfish. In addition, a few species, such as V. cholerae and V. parahaemolyticus, are risky for humans due to infections from eating raw shellfish infected with these bacteria or from exposure of wounds to the marine environment. Bacterial flagella are not essential to live in a culture medium. However, most Vibrio species are motile and have rotating flagella which allow them to move into favorable environments or to escape from unfavorable environments. This review summarizes recent studies about the flagellar structure, function, and regulation of Vibrio species, especially focused on the Na+-driven polar flagella that are principally responsible for motility and sensing the surrounding environment, and discusses the relationship between flagella and pathogenicity.
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Affiliation(s)
- Shiwei Zhu
- Division of Biological Science, Graduate School of Science, Nagoya University Nagoya, Japan
| | - Seiji Kojima
- Division of Biological Science, Graduate School of Science, Nagoya University Nagoya, Japan
| | - Michio Homma
- Division of Biological Science, Graduate School of Science, Nagoya University Nagoya, Japan
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Ceccarelli D, Hasan NA, Huq A, Colwell RR. Distribution and dynamics of epidemic and pandemic Vibrio parahaemolyticus virulence factors. Front Cell Infect Microbiol 2013; 3:97. [PMID: 24377090 PMCID: PMC3858888 DOI: 10.3389/fcimb.2013.00097] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 11/23/2013] [Indexed: 12/18/2022] Open
Abstract
Vibrio parahaemolyticus, autochthonous to estuarine, marine, and coastal environments throughout the world, is the causative agent of food-borne gastroenteritis. More than 80 serotypes have been described worldwide, based on antigenic properties of the somatic (O) and capsular (K) antigens. Serovar O3:K6 emerged in India in 1996 and subsequently was isolated worldwide, leading to the conclusion that the first V. parahaemolyticus pandemic had taken place. Most strains of V. parahaemolyticus isolated from the environment or seafood, in contrast to clinical strains, do not produce a thermostable direct hemolysin (TDH) and/or a TDH-related hemolysin (TRH). Type 3 secretion systems (T3SSs), needle-like apparatuses able to deliver bacterial effectors into host cytoplasm, were identified as triggering cytotoxicity and enterotoxicity. Type 6 secretion systems (T6SS) predicted to be involved in intracellular trafficking and vesicular transport appear to play a role in V. parahaemolyticus virulence. Recent advances in V. parahaemolyticus genomics identified several pathogenicity islands (VpaIs) located on either chromosome in both epidemic and pandemic strains and comprising additional colonization factors, such as restriction-modification complexes, chemotaxis proteins, classical bacterial surface virulence factors, and putative colicins. Furthermore, studies indicate strains lacking toxins and genomic regions associated with pathogenicity may also be pathogenic, suggesting other important virulence factors remain to be identified. The unique repertoire of virulence factors identified to date, their occurrence and distribution in both epidemic and pandemic strains worldwide are described, with the aim of highlighting the complexity of V. parahaemolyticus pathogenicity as well as its dynamic genome.
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Affiliation(s)
- Daniela Ceccarelli
- Maryland Pathogen Research Institute, University of Maryland College Park, MD, USA
| | - Nur A Hasan
- Maryland Pathogen Research Institute, University of Maryland College Park, MD, USA ; CosmosID Inc. College Park, MD, USA
| | - Anwar Huq
- Maryland Pathogen Research Institute, University of Maryland College Park, MD, USA ; Maryland Institute of Applied Environmental Health, University of Maryland College Park, MD, USA
| | - Rita R Colwell
- Maryland Pathogen Research Institute, University of Maryland College Park, MD, USA ; CosmosID Inc. College Park, MD, USA ; Maryland Institute of Applied Environmental Health, University of Maryland College Park, MD, USA ; Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University Baltimore, MD, USA
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