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Sadeeshkumar H, Balaji A, Sutherland AG, Mootien S, Anthony KG, Breaker RR. Screening for small molecule inhibitors of SAH nucleosidase using an SAH riboswitch. Anal Biochem 2023; 666:115047. [PMID: 36682579 PMCID: PMC11149561 DOI: 10.1016/j.ab.2023.115047] [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: 10/21/2022] [Revised: 12/30/2022] [Accepted: 01/09/2023] [Indexed: 01/21/2023]
Abstract
Due to the emergence of multidrug resistant pathogens, it is imperative to identify new targets for antibiotic drug discovery. The S-adenosylhomocysteine (SAH) nucleosidase enzyme is a promising target for antimicrobial drug development due to its critical functions in multiple bacterial processes including recycling of toxic byproducts of S-adenosylmethionine (SAM)-mediated reactions and producing the precursor of the universal quorum sensing signal, autoinducer-2 (AI-2). Riboswitches are structured RNA elements typically used by bacteria to precisely monitor and respond to changes in essential bacterial processes, including metabolism. Natural riboswitches fused to a reporter gene can be exploited to detect changes in metabolism or in physiological signaling. We performed a high-throughput screen (HTS) using an SAH-riboswitch controlled β-galactosidase reporter gene in Escherichia coli to discover small molecules that inhibit SAH recycling. We demonstrate that the assay strategy using SAH riboswitches to detect the effects of SAH nucleosidase inhibitors can quickly identify compounds that penetrate the barriers of Gram-negative bacterial cells and perturb pathways involving SAH.
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Affiliation(s)
- Harini Sadeeshkumar
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06520-8103, USA
| | - Aparaajita Balaji
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06520-8103, USA
| | | | | | - Karen G Anthony
- L2 Diagnostics, LLC, 300 George Street, New Haven, CT, 06511, USA
| | - Ronald R Breaker
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06520-8103, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520-8103, USA; Howard Hughes Medical Institute, Yale University, New Haven, CT, 06520-8103, USA.
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2
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Fan Q, Zuo J, Wang H, Grenier D, Yi L, Wang Y. Contribution of quorum sensing to virulence and antibiotic resistance in zoonotic bacteria. Biotechnol Adv 2022; 59:107965. [PMID: 35487393 DOI: 10.1016/j.biotechadv.2022.107965] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 04/15/2022] [Accepted: 04/21/2022] [Indexed: 11/02/2022]
Abstract
Quorum sensing (QS), which is a key part of cell/cell communication, is widely distributed in microorganisms, especially in bacteria. Bacteria can produce and detect the presence of QS signal molecule, perceive the composition and density of microorganisms in their complex habitat, and then dynamically regulate their own gene expression to adapt to their environment. Among the many traits controlled by QS in pathogenic bacteria is the expression of virulence factors and antibiotic resistance. Many pathogenic bacteria rely on QS to govern the production of virulence factors and express drug-resistance, especially in zoonotic bacteria. The threat of antibiotic resistant zoonotic bacteria has called for alternative antimicrobial strategies that would mitigate the increase of classical resistance mechanism. Targeting QS has proven to be a promising alternative to conventional antibiotic for controlling infections. Here we review the QS systems in common zoonotic pathogenic bacteria and outline how QS may control the virulence and antibiotic resistance of zoonotic bacteria.
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Affiliation(s)
- Qingying Fan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China
| | - Jing Zuo
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China
| | - Haikun Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China
| | - Daniel Grenier
- Groupe de Recherche en Écologie Buccale (GREB), Faculté de Médecine Dentaire, Université Laval, Quebec City, Canada
| | - Li Yi
- Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China; College of Life Science, Luoyang Normal University, Luoyang, China.
| | - Yang Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China.
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3
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Marmion M, Macori G, Ferone M, Whyte P, Scannell A. Survive and thrive: Control mechanisms that facilitate bacterial adaptation to survive manufacturing-related stress. Int J Food Microbiol 2022; 368:109612. [DOI: 10.1016/j.ijfoodmicro.2022.109612] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 02/21/2022] [Accepted: 03/02/2022] [Indexed: 10/18/2022]
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4
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Keizers M, Dobrindt U, Berger M. A Simple Biosensor-Based Assay for Quantitative Autoinducer-2 Analysis. ACS Synth Biol 2022; 11:747-759. [PMID: 35090122 DOI: 10.1021/acssynbio.1c00459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bacteria produce and react to interspecies signaling molecules in order to control the expression of genes that are particularly beneficial when they are expressed by a bacterial community. In addition to intraspecies communication, the signaling molecule autoinducer-2 (AI-2) can also serve for interspecies communication between Gram-positive and Gram-negative bacteria and is therefore of particular interest. The analysis and quantification of AI-2 are essential for understanding population density-dependent changes in bacterial behavior and pathogenicity. However, currently available bioassays for AI-2 quantification are rather complex, have narrow detection ranges, and are very sensitive to trace components of, for example, growth media. To facilitate and improve the detection of AI-2, we have developed an Escherichia coli biosensor-based assay that is sensitive, cheap, fast, robust, and reliable in the quantification of biologically active AI-2. The bioassay is based on an lsr promoter-fluorescent reporter gene fusion cassette that we chromosomally integrated in a biosensor strain, but the cassette can also be used in a low-copy number plasmid for the application in other Gram-negative bacterial species. We show here that AI-2 quantification was possible in a concentration range from 400 nM to 100 μM and that a critical interpretation of the kinetics of the measurements can reveal sugar interference. With the help of our biosensor strain, coculture experiments were done to test the capability and kinetics of AI-2 secretion by various Gram-negative bacteria in real time. Finally, calibration curves were used to calculate the absolute AI-2 concentration in cell-free bacterial samples.
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Affiliation(s)
- Marla Keizers
- Institute of Hygiene, University of Münster, Münster 48149, Germany
| | - Ulrich Dobrindt
- Institute of Hygiene, University of Münster, Münster 48149, Germany
| | - Michael Berger
- Institute of Hygiene, University of Münster, Münster 48149, Germany
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5
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For the Greater (Bacterial) Good: Heterogeneous Expression of Energetically Costly Virulence Factors. Infect Immun 2020; 88:IAI.00911-19. [PMID: 32041785 DOI: 10.1128/iai.00911-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Bacterial populations are phenotypically heterogeneous, which allows subsets of cells to survive and thrive following changes in environmental conditions. For bacterial pathogens, changes within the host environment occur over the course of the immune response to infection and can result in exposure to host-derived, secreted antimicrobials or force direct interactions with immune cells. Many recent studies have shown host cell interactions promote virulence factor expression, forcing subsets of bacterial cells to battle the host response, while other bacteria reap the benefits of this pacification. It still remains unclear whether virulence factor expression is truly energetically costly within host tissues and whether expression is sufficient to impact the growth kinetics of virulence factor-expressing cells. However, it is clear that slow-growing subsets of bacteria emerge during infection and that these subsets are particularly difficult to eliminate with antibiotics. This minireview will focus on our current understanding of heterogenous virulence factor expression and discuss the evidence that supports or refutes the hypothesis that virulence factor expression is linked to slowed growth and antibiotic tolerance.
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Kim CS, Li JH, Barco B, Park HB, Gatsios A, Damania A, Wang R, Wyche TP, Piizzi G, Clay NK, Crawford JM. Cellular Stress Upregulates Indole Signaling Metabolites in Escherichia coli. Cell Chem Biol 2020; 27:698-707.e7. [PMID: 32243812 PMCID: PMC7306003 DOI: 10.1016/j.chembiol.2020.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/04/2020] [Accepted: 03/02/2020] [Indexed: 12/13/2022]
Abstract
Escherichia coli broadly colonize the intestinal tract of humans and produce a variety of small molecule signals. However, many of these small molecules remain unknown. Here, we describe a family of widely distributed bacterial metabolites termed the "indolokines." In E. coli, the indolokines are upregulated in response to a redox stressor via aspC and tyrB transaminases. Although indolokine 1 represents a previously unreported metabolite, four of the indolokines (2-5) were previously shown to be derived from indole-3-carbonyl nitrile (ICN) in the plant pathogen defense response. We show that the indolokines are produced in a convergent evolutionary manner relative to plants, enhance E. coli persister cell formation, outperform ICN protection in an Arabidopsis thaliana-Pseudomonas syringae infection model, trigger a hallmark plant innate immune response, and activate distinct immunological responses in primary human tissues. Our molecular studies link a family of cellular stress-induced metabolites to defensive responses across bacteria, plants, and humans.
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Affiliation(s)
- Chung Sub Kim
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Chemical Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Jhe-Hao Li
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Chemical Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Brenden Barco
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - Hyun Bong Park
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Chemical Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Alexandra Gatsios
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Chemical Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Ashiti Damania
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - Rurun Wang
- Exploratory Science Center, Merck & Co., Inc., Cambridge, MA 02141, USA
| | - Thomas P Wyche
- Exploratory Science Center, Merck & Co., Inc., Cambridge, MA 02141, USA
| | - Grazia Piizzi
- Exploratory Science Center, Merck & Co., Inc., Cambridge, MA 02141, USA
| | - Nicole K Clay
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - Jason M Crawford
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Chemical Biology Institute, Yale University, West Haven, CT 06516, USA; Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT 06536, USA.
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7
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Sun W, Singh AK. Plague vaccine: recent progress and prospects. NPJ Vaccines 2019; 4:11. [PMID: 30792905 PMCID: PMC6379378 DOI: 10.1038/s41541-019-0105-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 12/19/2018] [Indexed: 01/14/2023] Open
Abstract
Three great plague pandemics, resulting in nearly 200 million deaths in human history and usage as a biowarfare agent, have made Yersinia pestis as one of the most virulent human pathogens. In late 2017, a large plague outbreak raged in Madagascar attracted extensive attention and caused regional panics. The evolution of local outbreaks into a pandemic is a concern of the Centers for Disease Control and Prevention (CDC) in plague endemic regions. Until now, no licensed plague vaccine is available. Prophylactic vaccination counteracting this disease is certainly a primary choice for its long-term prevention. In this review, we summarize the latest advances in research and development of plague vaccines.
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Affiliation(s)
- Wei Sun
- Department of Immunology and Microbial Disease, Albany Medical College, Albany, NY 12208 USA
| | - Amit K. Singh
- Department of Immunology and Microbial Disease, Albany Medical College, Albany, NY 12208 USA
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8
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Fleitas Martínez O, Rigueiras PO, Pires ÁDS, Porto WF, Silva ON, de la Fuente-Nunez C, Franco OL. Interference With Quorum-Sensing Signal Biosynthesis as a Promising Therapeutic Strategy Against Multidrug-Resistant Pathogens. Front Cell Infect Microbiol 2019; 8:444. [PMID: 30805311 PMCID: PMC6371041 DOI: 10.3389/fcimb.2018.00444] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 12/12/2018] [Indexed: 12/11/2022] Open
Abstract
Faced with the global health threat of increasing resistance to antibiotics, researchers are exploring interventions that target bacterial virulence factors. Quorum sensing is a particularly attractive target because several bacterial virulence factors are controlled by this mechanism. Furthermore, attacking the quorum-sensing signaling network is less likely to select for resistant strains than using conventional antibiotics. Strategies that focus on the inhibition of quorum-sensing signal production are especially attractive because the enzymes involved are expressed in bacterial cells but are not present in their mammalian counterparts. We review here various approaches that are being taken to interfere with quorum-sensing signal production via the inhibition of autoinducer-2 synthesis, PQS synthesis, peptide autoinducer synthesis, and N-acyl-homoserine lactone synthesis. We expect these approaches will lead to the discovery of new quorum-sensing inhibitors that can help to stem the tide of antibiotic resistance.
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Affiliation(s)
- Osmel Fleitas Martínez
- Programa de Pós-Graduação em Patologia Molecular, Universidade de Brasília, Brasília, Brazil.,Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil
| | - Pietra Orlandi Rigueiras
- Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil
| | - Állan da Silva Pires
- Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil
| | - William Farias Porto
- Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil.,S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, Brazil.,Porto Reports, Brasília, Brazil
| | - Osmar Nascimento Silva
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, Brazil
| | - Cesar de la Fuente-Nunez
- Synthetic Biology Group, MIT Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, United States.,Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, United States.,Department of Biological Engineering, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States.,Broad Institute of MIT and Harvard, Cambridge, MA, United States.,The Center for Microbiome Informatics and Therapeutics, Cambridge, MA, United States
| | - Octavio Luiz Franco
- Programa de Pós-Graduação em Patologia Molecular, Universidade de Brasília, Brasília, Brazil.,Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil.,S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, Brazil
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Hu X, Wang Y, Gao L, Jiang W, Lin W, Niu C, Yuan K, Ma R, Huang Z. The Impairment of Methyl Metabolism From luxS Mutation of Streptococcus mutans. Front Microbiol 2018; 9:404. [PMID: 29657574 PMCID: PMC5890193 DOI: 10.3389/fmicb.2018.00404] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 02/21/2018] [Indexed: 12/19/2022] Open
Abstract
The luxS gene is present in a wide range of bacteria and is involved in many cellular processes. LuxS mutation can cause autoinducer(AI)-2 deficiency and methyl metabolism disorder. The objective of this study was to demonstrate that, in addition to AI-2-mediated quorum sensing (QS), methyl metabolism plays an important role in LuxS regulation in Streptococcus mutans. The sahH gene from Pseudomonas aeruginosa was amplified and introduced into the S. mutans luxS-null strain to complement the methyl metabolism disruption in a defective QS phenotype. The intracellular activated methyl cycle (AMC) metabolites [S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), homocysteine (HCY), and methionine] were quantified in wild-type S. mutans and its three derivatives to determine the metabolic effects of disrupting the AMC. Biofilm mass and structure, acid tolerance, acid production, exopolysaccharide synthesis of multispecies biofilms and the transcriptional level of related genes were determined. The results indicated that SAH and SAM were relatively higher in S. mutans luxS-null strain and S. mutans luxS null strain with plasmid pIB169 when cultured overnight, and HCY was significantly higher in S. mutans UA159. Consistent with the transcriptional profile, luxS deletion-mediated impairment of biofilm formation and acid tolerance was restored to wild-type levels using transgenic SahH. These results also suggest that methionine methyl metabolism contributes to LuxS regulation in S. mutans to a significant degree.
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Affiliation(s)
- Xuchen Hu
- Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, National Clinical Research Center of Stomatology, Shanghai, China
| | - Yuxia Wang
- Department of Endodontics, Tianjin Stomatological Hospital, Nankai University, Tianjin, China
| | - Li Gao
- Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, National Clinical Research Center of Stomatology, Shanghai, China
| | - Wenxin Jiang
- Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, National Clinical Research Center of Stomatology, Shanghai, China
| | - Wenzhen Lin
- Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, National Clinical Research Center of Stomatology, Shanghai, China
| | - Chenguang Niu
- Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, National Clinical Research Center of Stomatology, Shanghai, China
| | - Keyong Yuan
- Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, National Clinical Research Center of Stomatology, Shanghai, China
| | - Rui Ma
- Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, National Clinical Research Center of Stomatology, Shanghai, China
| | - Zhengwei Huang
- Department of Endodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, National Clinical Research Center of Stomatology, Shanghai, China
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Andersson JA, Sha J, Erova TE, Fitts EC, Ponnusamy D, Kozlova EV, Kirtley ML, Chopra AK. Identification of New Virulence Factors and Vaccine Candidates for Yersinia pestis. Front Cell Infect Microbiol 2017; 7:448. [PMID: 29090192 PMCID: PMC5650977 DOI: 10.3389/fcimb.2017.00448] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 09/29/2017] [Indexed: 11/13/2022] Open
Abstract
Earlier, we reported the identification of new virulence factors/mechanisms of Yersinia pestis using an in vivo signature-tagged mutagenesis (STM) screening approach. From this screen, the role of rbsA, which encodes an ATP-binding protein of ribose transport system, and vasK, an essential component of the type VI secretion system (T6SS), were evaluated in mouse models of plague and confirmed to be important during Y. pestis infection. However, many of the identified genes from the screen remained uncharacterized. In this study, in-frame deletion mutants of ypo0815, ypo2884, ypo3614-3168 (cyoABCDE), and ypo1119-1120, identified from the STM screen, were generated. While ypo0815 codes for a general secretion pathway protein E (GspE) of the T2SS, the ypo2884-encoded protein has homology to the βγ crystallin superfamily, cyoABCDE codes for the cytochrome o oxidase operon, and the ypo1119-1120 genes are within the Tol-Pal system which has multiple functions. Additionally, as our STM screen identified three T6SS-associated genes, and, based on in silico analysis, six T6SS clusters and multiple homologs of the T6SS effector hemolysin-coregulated protein (Hcp) exist in Y. pestis CO92, we also targeted these T6SS clusters and effectors for generating deletion mutants. These deletion mutant strains exhibited varying levels of attenuation (up to 100%), in bubonic or pneumonic murine infection models. The attenuation could be further augmented by generation of combinatorial deletion mutants, namely ΔlppΔypo0815, ΔlppΔypo2884, ΔlppΔcyoABCDE, ΔvasKΔhcp6, and Δypo2720-2733Δhcp3. We earlier showed that deletion of the lpp gene, which encodes Braun lipoprotein (Lpp) and activates Toll-like receptor-2, reduced virulence of Y. pestis CO92 in murine models of bubonic and pneumonic plague. The surviving mice infected with ΔlppΔcyoABCDE, ΔvasKΔhcp6, and Δypo2720-2733Δhcp3 mutant strains were 55-100% protected upon subsequent re-challenge with wild-type CO92 in a pneumonic model. Further, evaluation of the attenuated T6SS mutant strains in vitro revealed significant alterations in phagocytosis, intracellular survival in murine macrophages, and their ability to induce cytotoxic effects on macrophages. The results reported here provide further evidence of the utility of the STM screening approach for the identification of novel virulence factors and to possibly target such genes for the development of novel live-attenuated vaccine candidates for plague.
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Affiliation(s)
- Jourdan A Andersson
- Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX, United States
| | - Jian Sha
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States.,Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, United States
| | - Tatiana E Erova
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Eric C Fitts
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Duraisamy Ponnusamy
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Elena V Kozlova
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Michelle L Kirtley
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States
| | - Ashok K Chopra
- Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX, United States.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, United States.,Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, United States.,WHO Collaborating Center for Vaccine Development, University of Texas Medical Branch, Galveston, TX, United States.,Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, United States
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