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Sachdeva C, Satyamoorthy K, Murali TS. Pseudomonas aeruginosa: metabolic allies and adversaries in the world of polymicrobial infections. Crit Rev Microbiol 2024:1-20. [PMID: 39225080 DOI: 10.1080/1040841x.2024.2397359] [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: 09/25/2023] [Revised: 08/10/2024] [Accepted: 08/21/2024] [Indexed: 09/04/2024]
Abstract
Pseudomonas aeruginosa (PA), an opportunistic human pathogen that is frequently linked with chronic infections in immunocompromised individuals, is also metabolically versatile, and thrives in diverse environments. Additionally, studies report that PA can interact with other microorganisms, such as bacteria, and fungi, producing unique metabolites that can modulate the host immune response, and contribute to disease pathogenesis. This review summarizes the current knowledge related to the metabolic interactions of PA with other microorganisms (Staphylococcus, Acinetobacter, Klebsiella, Enterococcus, and Candida) and human hosts, and the importance of these interactions in a polymicrobial context. Further, we highlight the potential applications of studying these metabolic interactions toward designing better diagnostic tools, and therapeutic strategies to prevent, and treat infections caused by this pathogen.
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Affiliation(s)
- Chandni Sachdeva
- Department of Public Health Genomics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Kapaettu Satyamoorthy
- Department of Cell & Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
- SDM College of Medical Sciences and Hospital, Shri Dharmasthala Manjunatheshwara (SDM) University, Sattur, Karnataka, India
| | - Thokur Sreepathy Murali
- Department of Public Health Genomics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
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2
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Eschrig S, Kahlon PS, Agius C, Holzer A, Hückelhoven R, Schwechheimer C, Ranf S. Cross-family transfer of the Arabidopsis cell-surface immune receptor LORE to tomato confers sensing of 3-hydroxylated fatty acids and enhanced disease resistance. MOLECULAR PLANT PATHOLOGY 2024; 25:e70005. [PMID: 39235143 DOI: 10.1111/mpp.70005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 08/14/2024] [Accepted: 08/18/2024] [Indexed: 09/06/2024]
Abstract
Plant pathogens pose a high risk of yield losses and threaten food security. Technological and scientific advances have improved our understanding of the molecular processes underlying host-pathogen interactions, which paves the way for new strategies in crop disease management beyond the limits of conventional breeding. Cross-family transfer of immune receptor genes is one such strategy that takes advantage of common plant immune signalling pathways to improve disease resistance in crops. Sensing of microbe- or host damage-associated molecular patterns (MAMPs/DAMPs) by plasma membrane-resident pattern recognition receptors (PRR) activates pattern-triggered immunity (PTI) and restricts the spread of a broad spectrum of pathogens in the host plant. In the model plant Arabidopsis thaliana, the S-domain receptor-like kinase LIPOOLIGOSACCHARIDE-SPECIFIC REDUCED ELICITATION (AtLORE, SD1-29) functions as a PRR, which senses medium-chain-length 3-hydroxylated fatty acids (mc-3-OH-FAs), such as 3-OH-C10:0, and 3-hydroxyalkanoates (HAAs) of microbial origin to activate PTI. In this study, we show that ectopic expression of the Brassicaceae-specific PRR AtLORE in the solanaceous crop species Solanum lycopersicum leads to the gain of 3-OH-C10:0 immune sensing without altering plant development. AtLORE-transgenic tomato shows enhanced resistance against Pseudomonas syringae pv. tomato DC3000 and Alternaria solani NL03003. Applying 3-OH-C10:0 to the soil before infection induces resistance against the oomycete pathogen Phytophthora infestans Pi100 and further enhances resistance to A. solani NL03003. Our study proposes a potential application of AtLORE-transgenic crop plants and mc-3-OH-FAs as resistance-inducing biostimulants in disease management.
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Affiliation(s)
- Sabine Eschrig
- TUM School of Life Sciences, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Parvinderdeep S Kahlon
- TUM School of Life Sciences, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Carlos Agius
- TUM School of Life Sciences, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Andrea Holzer
- TUM School of Life Sciences, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Ralph Hückelhoven
- TUM School of Life Sciences, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Claus Schwechheimer
- TUM School of Life Sciences, Technical University of Munich, Freising-Weihenstephan, Germany
| | - Stefanie Ranf
- TUM School of Life Sciences, Technical University of Munich, Freising-Weihenstephan, Germany
- Department of Biology, University of Fribourg, Fribourg, Switzerland
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3
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Yang H, O’Keefe I, Smith RD, Sumner KP, Sherman ME, Goodlett DR, Sweet CR, Ernst RK. A Multimodal System for Lipid A Structural Analysis from a Single Colony. Anal Chem 2024; 96. [PMID: 39149983 PMCID: PMC11359392 DOI: 10.1021/acs.analchem.4c01566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Revised: 08/02/2024] [Accepted: 08/05/2024] [Indexed: 08/17/2024]
Abstract
Structural elucidation of Gram-negative bacterial lipid A traditionally requires chemical extraction followed by tandem MS data in the negative ion mode. Previously, we reported FLAT and FLATn as methods to rapidly determine the structure of lipid A without chromatographic techniques. In this work, we extend the capability and effectiveness of these techniques to elucidate the chemical structure in a de novo manner by including the use of positive ion mode (FLAT+ and FLATn+) spectral approaches. Advantages of positive mode analysis of lipid A include the generation of more interpretable and informative fragmentation patterns that include the identification of diagnostic fragments, including selective dissociation of a glycosidic bond between two glucosamine units and the selective dissociation at the secondary acyl chain in 2'-N, allowing for the determination of the composition of fatty acids. As a proof of principle, we present here two previously uncharacterized structures of lipid A from Roseomonas mucosa (R. mucosa) and Moraxella canis (M. canis). In R. mucosa, we determined the lipid A structure with a nonconventional backbone of-β-1,6 linked 2,3-dideoxy-2,3-diamno-d-glucopyranose further modified with galacturonic acid in the place of typical 1-phosphate, and in M. canis, we assigned a single discrete structure using the specific fragmentation patterns of terminal phosphate groups present in lipid A. Therefore, FLATn+, in combination with FLAT and FLATn, provides a multimodal structural platform for rapid structure characterization of unusual and complex lipid A structures from a single colony.
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Affiliation(s)
- Hyojik Yang
- Department
of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, Maryland 21201, United States
| | - Ian O’Keefe
- Department
of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, Maryland 21201, United States
| | - Richard D. Smith
- Department
of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, Maryland 21201, United States
- Department
of Pathology, School of Medicine, University
of Maryland, Baltimore, Maryland 21201, United
States
| | - Kylie P. Sumner
- Department
of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, Maryland 21201, United States
| | - Matthew E. Sherman
- Department
of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, Maryland 21201, United States
| | - David R. Goodlett
- Department
of Biochemistry and Microbiology, University
of Victoria, Victoria, British Columbia V8P 5C2, Canada
- Genome
British Columbia Proteomics Centre, University
of Victoria, Victoria, British Columbia V8Z 7Z8, Canada
| | - Charles R. Sweet
- Chemistry
Department, United States Naval Academy, Annapolis, Maryland 21402, United States
| | - Robert K. Ernst
- Department
of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, Maryland 21201, United States
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4
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Hofstaedter CE, O’Keefe IP, Met CM, Wu L, Vanderwoude J, Shin S, Diggle SP, Riquelme SA, Rasko DA, Doi Y, Harro JM, Kopp BT, Ernst RK. Pseudomonas aeruginosa Lipid A Structural Variants Induce Altered Immune Responses. Am J Respir Cell Mol Biol 2024; 71:207-218. [PMID: 38656811 PMCID: PMC11299085 DOI: 10.1165/rcmb.2024-0059oc] [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: 02/09/2024] [Accepted: 04/23/2024] [Indexed: 04/26/2024] Open
Abstract
Pseudomonas aeruginosa causes chronic lung infection in cystic fibrosis (CF), resulting in structural lung damage and progressive pulmonary decline. P. aeruginosa in the CF lung undergoes numerous changes, adapting to host-specific airway pressures while establishing chronic infection. P. aeruginosa undergoes lipid A structural modification during CF chronic infection that is not seen in any other disease state. Lipid A, the membrane anchor of LPS (i.e., endotoxin), comprises the majority of the outer membrane of Gram-negative bacteria and is a potent Toll-like receptor 4 (TLR4) agonist. The structure of P. aeruginosa lipid A is intimately linked with its recognition by TLR4 and subsequent immune response. Prior work has identified P. aeruginosa strains with altered lipid A structures that arise during chronic CF lung infection; however, the impact of the P. aeruginosa lipid A structure on airway disease has not been investigated. Here, we show that P. aeruginosa lipid A lacks PagL-mediated deacylation during human airway infection using a direct-from-sample mass spectrometry approach on human BAL fluid. This structure triggers increased proinflammatory cytokine production by primary human macrophages. Furthermore, alterations in lipid A 2-hydroxylation impact cytokine response in a site-specific manner, independent of CF transmembrane conductance regulator function. It is interesting that there is a CF-specific reduction in IL-8 secretion within the epithelial-cell compartment that only occurs in CF bronchial epithelial cells when infected with CF-adapted P. aeruginosa that lacks PagL-mediated lipid A deacylation. Taken together, we show that P. aeruginosa alters its lipid A structure during acute lung infection and that this lipid A structure induces stronger signaling through TLR4.
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Affiliation(s)
| | | | | | - Ling Wu
- Department of Microbiology and
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jelly Vanderwoude
- Center for Microbial Dynamics and Infection, School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia
| | | | - Stephen P. Diggle
- Center for Microbial Dynamics and Infection, School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia
| | | | - David A. Rasko
- Institute for Genome Sciences
- Department of Microbiology and Immunology, and
- Center for Pathogen Research, University of Maryland, Baltimore, Baltimore, Maryland
| | - Yohei Doi
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; and
| | | | - Benjamin T. Kopp
- Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Emory University, Atlanta, Georgia
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Puca V, Marinacci B, Pellegrini B, Campanile F, Santagati M, Grande R. Biofilm and bacterial membrane vesicles: recent advances. Expert Opin Ther Pat 2024; 34:475-491. [PMID: 38578180 DOI: 10.1080/13543776.2024.2338101] [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: 11/14/2023] [Accepted: 03/21/2024] [Indexed: 04/06/2024]
Abstract
INTRODUCTION Bacterial Membrane Vesicles (MVs) play important roles in cell-to-cell communication and transport of several molecules. Such structures are essential components of Extracellular Polymeric Substances (EPS) biofilm matrix of many bacterial species displaying a structural function and a role in virulence and pathogenesis. AREAS COVERED In this review were included original articles from the last ten years by searching the keywords 'biofilm' and 'vesicles' on PUBMED and Scopus databases. The articles available in literature mainly describe a positive correlation between bacterial MVs and biofilms formation. The research on Espacenet and Google Patent databases underlines the available patents related to the application of both biofilm MVs and planktonic MVs in inhibiting biofilm formation. EXPERT OPINION This review covers and analyzes recent advances in the study of the relationship between bacterial vesicles and biofilm. The huge number of papers discussing the role of MVs confirms the interest aimed at developing new applications in the medical field. The study of the MVs composition and biogenesis may contribute to the identification of components which could be (i) the target for the development of new drugs inhibiting the biofilm establishment; (ii) candidates for the development of vaccines; (iii) biomarkers for the diagnosis of bacterial infections.
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Affiliation(s)
- Valentina Puca
- Department of Pharmacy, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Beatrice Marinacci
- Department of Pharmacy, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
- Department of Innovative Technologies in Medicine & Dentistry, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Benedetta Pellegrini
- Department of Pharmacy, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
| | - Floriana Campanile
- Department of Biomedical and Biotechnological Sciences (BIOMETEC) - Microbiology Section, University of Catania, Catania, Italy
| | - Maria Santagati
- Department of Biomedical and Biotechnological Sciences (BIOMETEC) - Microbiology Section, University of Catania, Catania, Italy
| | - Rossella Grande
- Department of Pharmacy, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
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Hofstaedter CE, Chandler CE, Met CM, Gillespie JJ, Harro JM, Goodlett DR, Rasko DA, Ernst RK. Divergent Pseudomonas aeruginosa LpxO enzymes perform site-specific lipid A 2-hydroxylation. mBio 2024; 15:e0282323. [PMID: 38131669 PMCID: PMC10865791 DOI: 10.1128/mbio.02823-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023] Open
Abstract
Pseudomonas aeruginosa can survive in a myriad of environments, partially due to modifications of its lipid A, the membrane anchor of lipopolysaccharide. We previously demonstrated that divergent late acyltransferase paralogs, HtrB1 and HtrB2, add acyloxyacyl laurate to lipid A 2- and 2'-acyl chains, respectively. The genome of P. aeruginosa also has genes which encode two dioxygenase enzymes, LpxO1 and LpxO2, that individually hydroxylate a specific secondary laurate. LpxO1 acts on the 2'-acyloxyacyl laurate (added by HtrB2), whereas LpxO2 acts on the 2-acyloxyacyl laurate (added by HtrB1) in a site-specific manner. Furthermore, while both enzyme pairs are evolutionarily linked, phylogenomic analysis suggests the LpxO1/HtrB2 enzyme pair as being of ancestral origin, present throughout the Pseudomonas lineage, whereas the LpxO2/HtrB1 enzyme pair likely arose via horizontal gene transfer and has been retained in P. aeruginosa over time. Using a murine pulmonary infection model, we showed that both LpxO1 and LpxO2 enzymes are functional in vivo, as direct analysis of in vivo lipid A structure from bronchoalveolar lavage fluid revealed 2-hydroxylated lipid A. Gene expression analysis reveals increased lpxO2 but unchanged lpxO1 expression in vivo, suggesting differential regulation of these enzymes during infection. We also demonstrate that loss-of-function mutations arise in lpxO1 and lpxO2 during chronic lung infection in people with cystic fibrosis (CF), indicating a potential role for pathogenesis and airway adaptation. Collectively, our study characterizes lipid A 2-hydroxylation during P. aeruginosa airway infection that is regulated by two distinct lipid A dioxygenase enzymes.IMPORTANCEPseudomonas aeruginosa is an opportunistic pathogen that causes severe infection in hospitalized and chronically ill individuals. During infection, P. aeruginosa undergoes adaptive changes to evade host defenses and therapeutic interventions, increasing mortality and morbidity. Lipid A structural alteration is one such change that P. aeruginosa isolates undergo during chronic lung infection in CF. Investigating genetic drivers of this lipid A structural variation is crucial in understanding P. aeruginosa adaptation during infection. Here, we describe two lipid A dioxygenases with acyl-chain site specificity, each with different evolutionary origins. Further, we show that loss of function in these enzymes occurs in CF clinical isolates, suggesting a potential pathoadaptive phenotype. Studying these bacterial adaptations provides insight into selection pressures of the CF airway on P. aeruginosa phenotypes that persist during chronic infection. Understanding these adaptive changes may ultimately provide clinicians better control over bacterial populations during chronic infection.
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Affiliation(s)
- Casey E. Hofstaedter
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore, Maryland, USA
- Medical Scientist Training Program, University of Maryland, Baltimore, Baltimore, Maryland, USA
| | - Courtney E. Chandler
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore, Maryland, USA
| | - Charles M. Met
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore, Maryland, USA
| | - Joseph J. Gillespie
- Department of Microbiology and Immunology, University of Maryland Baltimore, Baltimore, Maryland, USA
| | - Janette M. Harro
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore, Maryland, USA
| | - David R. Goodlett
- Departments of Biochemistry and Microbiology, University of Victoria, Victoria, Canada
| | - David A. Rasko
- Department of Microbiology and Immunology, University of Maryland Baltimore, Baltimore, Maryland, USA
- Institute for Genome Sciences, University of Maryland, Baltimore, Baltimore, Maryland, USA
- Center for Pathogen Research, University of Maryland, Baltimore, Baltimore, Maryland, USA
| | - Robert K. Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore, Maryland, USA
- Department of Microbiology and Immunology, University of Maryland Baltimore, Baltimore, Maryland, USA
- Center for Pathogen Research, University of Maryland, Baltimore, Baltimore, Maryland, USA
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7
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Yang H, Sherman ME, Koo CJ, Treaster LM, Smith JP, Gallaher SG, Goodlett DR, Sweet CR, Ernst RK. Structure Determination of Lipid A with Multiple Glycosylation Sites by Tandem MS of Lithium-Adducted Negative Ions. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:1047-1055. [PMID: 37184080 DOI: 10.1021/jasms.3c00014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
FLATn is a tandem mass spectrometric technique that can be used to rapidly generate spectral information applicable for structural elucidation of lipids like lipid A from Gram-negative bacterial species from a single bacterial colony. In this study, we extend the scope and capability of FLATn by tandem MS fragmentation of lithium-adducted molecular lipid A anions and fragments (FLATn-Li) that provides additional structural and diagnostic data from FLATn samples allowing for the discrimination of terminal phosphate modifications in a variety of pathogenic and environmental species. Using FLATn-Li, we elucidated the lipid A structure from several bacterial species, including novel structures from arctic bacterioplankton of the Duganella and Massilia genera that favor 4-amino-4-deoxy-l-arabinopyranose (Ara4N) modification at the 1-phosphate position and that demonstrate double glycosylation with Ara4N at the 1 and 4' phosphate positions simultaneously. The structures characterized in this work demonstrate that some environmental psychrophilic species make extensive use of this structural lipid A modification previously characterized as a pathogenic adaptation and the structural basis of resistance to cationic antimicrobial peptides. This observation extends the role of phosphate modification(s) in environmental species adaptation and suggests that Ara4N modification can functionally replace the positive charge of the phosphoethanolamine modification that is more typically found attached to the 1-phosphate position of modified lipid A.
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Affiliation(s)
- Hyojik Yang
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, Maryland 21201, United States of America
| | - Matthew E Sherman
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, Maryland 21201, United States of America
| | - Caitlyn J Koo
- Chemistry Department, United States Naval Academy, Annapolis, Maryland 21402, United States of America
- School of Medicine, Uniformed Services University, Bethesda, Maryland 20814, United States of America
| | - Logan M Treaster
- Chemistry Department, United States Naval Academy, Annapolis, Maryland 21402, United States of America
- School of Medicine, University of Kansas, Kansas City, Kansas 66160, United States of America
| | - Joseph P Smith
- Oceanography Department, United States Naval Academy, Annapolis, Maryland 21402, United States of America
| | - Shawn G Gallaher
- Oceanography Department, United States Naval Academy, Annapolis, Maryland 21402, United States of America
| | - David R Goodlett
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada
- Genome British Columbia Proteomics Centre, University of Victoria, Victoria, British Columbia V8Z 7Z8, Canada
| | - Charles R Sweet
- Chemistry Department, United States Naval Academy, Annapolis, Maryland 21402, United States of America
| | - Robert K Ernst
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, Maryland 21201, United States of America
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8
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Pětrošová H, Mikhael A, Culos S, Giraud-Gatineau A, Gomez AM, Sherman ME, Ernst RK, Cameron CE, Picardeau M, Goodlett DR. Lipid A structural diversity among members of the genus Leptospira. Front Microbiol 2023; 14:1181034. [PMID: 37303810 PMCID: PMC10248169 DOI: 10.3389/fmicb.2023.1181034] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 05/02/2023] [Indexed: 06/13/2023] Open
Abstract
Lipid A is the hydrophobic component of bacterial lipopolysaccharide and an activator of the host immune system. Bacteria modify their lipid A structure to adapt to the surrounding environment and, in some cases, to evade recognition by host immune cells. In this study, lipid A structural diversity within the Leptospira genus was explored. The individual Leptospira species have dramatically different pathogenic potential that ranges from non-infectious to life-threatening disease (leptospirosis). Ten distinct lipid A profiles, denoted L1-L10, were discovered across 31 Leptospira reference species, laying a foundation for lipid A-based molecular typing. Tandem MS analysis revealed structural features of Leptospira membrane lipids that might alter recognition of its lipid A by the host innate immune receptors. Results of this study will aid development of strategies to improve diagnosis and surveillance of leptospirosis, as well as guide functional studies on Leptospira lipid A activity.
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Affiliation(s)
- Helena Pětrošová
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
- University of Victoria Genome British Columbia Proteomics Center, University of Victoria, Victoria, BC, Canada
| | - Abanoub Mikhael
- University of Victoria Genome British Columbia Proteomics Center, University of Victoria, Victoria, BC, Canada
| | - Sophie Culos
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | | | - Alloysius M. Gomez
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | - Matthew E. Sherman
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, United States
| | - Robert K. Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, United States
| | - Caroline E. Cameron
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, United States
| | - Mathieu Picardeau
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Biology of Spirochetes Unit, Paris, France
| | - David R. Goodlett
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
- University of Victoria Genome British Columbia Proteomics Center, University of Victoria, Victoria, BC, Canada
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9
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Onyedibe KI, Nemeth AM, Dayal N, Smith RD, Lamptey J, Ernst RK, Melander RJ, Melander C, Sintim HO. Re-sensitization of Multidrug-Resistant and Colistin-Resistant Gram-Negative Bacteria to Colistin by Povarov/Doebner-Derived Compounds. ACS Infect Dis 2023; 9:283-295. [PMID: 36651182 PMCID: PMC10547215 DOI: 10.1021/acsinfecdis.2c00417] [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] [Indexed: 01/19/2023]
Abstract
Colistin, typically viewed as the antibiotic of last resort to treat infections caused by multidrug-resistant (MDR) Gram-negative bacteria, had fallen out of favor due to toxicity issues. The recent increase in clinical usage of colistin has resulted in colistin-resistant isolates becoming more common. To counter this threat, we have investigated previously reported compounds, HSD07 and HSD17, and developed 13 compounds with more desirable drug-like properties for colistin sensitization against 16 colistin-resistant bacterial strains, three of which harbor the plasmid-borne mobile colistin resistance (mcr-1). Lead compound HSD1624, which has a lower LogDpH7.4 (2.46) compared to HSD07 (>5.58), reduces the minimum inhibitory concentration (MIC) of colistin against Pseudomonas aeruginosa strain TRPA161 to 0.03 μg/mL from 1024 μg/mL (34,000-fold reduction). Checkerboard assays revealed that HSD1624 and analogues are also synergistic with colistin against colistin-resistant strains of Escherichia coli, Acinetobacter baumannii, and Klebsiella pneumoniae. Preliminary mechanism of action studies indicate that HSD1624 exerts its action differently depending on the bacterial species. Time-kill studies suggested that HSD1624 in combination with 0.5 μg/mL colistin was bactericidal to extended-spectrum beta-lactamase (ESBL)-producing E. coli, as well as to E. coli harboring mcr-1, while against P. aeruginosa TRPA161, the combination was bacteriostatic. Mechanistically, HSD1624 increased membrane permeability in K. pneumoniae harboring a plasmid containing the mcr-1 gene but did not increase radical oxygen species (ROS), while a combination of 15 μM HSD1624 and 0.5 μg/mL colistin significantly increased ROS in P. aeruginosa TRPA161. HSD1624 was not toxic to mammalian red blood cells (up to 226 μM).
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Affiliation(s)
- Kenneth I Onyedibe
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana47907, United States
- Center for Drug Discovery, Purdue University, 720 Clinic Drive, West Lafayette, Indiana47906, United States
- Purdue Institute of Inflammation, Immunology, and Infectious Disease, West Lafayette, Indiana47906, United States
| | - Ansley M Nemeth
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana46556, United States
| | - Neetu Dayal
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana47907, United States
- Center for Drug Discovery, Purdue University, 720 Clinic Drive, West Lafayette, Indiana47906, United States
| | - Richard D Smith
- Department of Microbial Pathogenesis, University of Maryland-Baltimore, Baltimore, Maryland21201, United States
| | - Jones Lamptey
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana47907, United States
- Center for Drug Discovery, Purdue University, 720 Clinic Drive, West Lafayette, Indiana47906, United States
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland-Baltimore, Baltimore, Maryland21201, United States
| | - Roberta J Melander
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana46556, United States
| | - Christian Melander
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana46556, United States
| | - Herman O Sintim
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana47907, United States
- Center for Drug Discovery, Purdue University, 720 Clinic Drive, West Lafayette, Indiana47906, United States
- Purdue Institute of Inflammation, Immunology, and Infectious Disease, West Lafayette, Indiana47906, United States
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10
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Gauthier AE, Rotjan RD, Kagan JC. Lipopolysaccharide detection by the innate immune system may be an uncommon defence strategy used in nature. Open Biol 2022; 12:220146. [PMID: 36196535 PMCID: PMC9533005 DOI: 10.1098/rsob.220146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 09/09/2022] [Indexed: 11/12/2022] Open
Abstract
Since the publication of the Janeway's Pattern Recognition hypothesis in 1989, study of pathogen-associated molecular patterns (PAMPs) and their immuno-stimulatory activities has accelerated. Most studies in this area have been conducted in model organisms, which leaves many open questions about the universality of PAMP biology across living systems. Mammals have evolved multiple proteins that operate as receptors for the PAMP lipopolysaccharide (LPS) from Gram-negative bacteria, but LPS is not immuno-stimulatory in all eukaryotes. In this review, we examine the history of LPS as a PAMP in mammals, recent data on LPS structure and its ability to activate mammalian innate immune receptors, and how these activities compare across commonly studied eukaryotes. We discuss why LPS may have evolved to be immuno-stimulatory in some eukaryotes but not others and propose two hypotheses about the evolution of PAMP structure based on the ecology and environmental context of the organism in question. Understanding PAMP structures and stimulatory mechanisms across multi-cellular life will provide insights into the evolutionary origins of innate immunity and may lead to the discovery of new PAMP variations of scientific and therapeutic interest.
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Affiliation(s)
- Anna E. Gauthier
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
- Program in Virology, Harvard Medical School, Boston, MA, USA
| | - Randi D. Rotjan
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA 02215, USA
| | - Jonathan C. Kagan
- Division of Gastroenterology, Boston Children's Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
- Harvard Medical School, and Boston Children's Hospital, Division of Immunology, Division of Gastroenterology, USA
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11
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Lyon R, Jones RA, Shropshire H, Aberdeen I, Scanlan DJ, Millard A, Chen Y. Membrane lipid renovation in Pseudomonas aeruginosa - implications for phage therapy? Environ Microbiol 2022; 24:4533-4546. [PMID: 35837865 PMCID: PMC9804370 DOI: 10.1111/1462-2920.16136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 01/05/2023]
Abstract
Pseudomonas aeruginosa is an important Gram-negative pathogen with intrinsic resistance to many clinically used antibiotics. It is particularly troublesome in nosocomial infections, immunocompromised patients, and individuals with cystic fibrosis. Antimicrobial resistance (AMR) is a huge threat to global health, with a predicted 10 million people dying from resistant infections by 2050. A promising therapy for combatting AMR infections is phage therapy. However, more research is required to investigate mechanisms that may influence the efficacy of phage therapy. An important overlooked aspect is the impact of membrane lipid remodelling on phage binding ability. P. aeruginosa undergoes changes in membrane lipids when it encounters phosphorus stress, an environmental perturbation that is likely to occur during infection. Lipid changes include the substitution of glycerophospholipids with surrogate glycolipids and the over-production of ornithine-containing aminolipids. Given that membrane lipids are known to influence the structure and function of membrane proteins, we propose that changes in the composition of membrane lipids during infection may alter phage binding and subsequent phage infection dynamics. Consideration of such effects needs to be urgently prioritised in order to develop the most effective phage therapy strategies for P. aeruginosa infections.
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Affiliation(s)
- Rhiannon Lyon
- BBSRC Midlands Integrative Biosciences Training PartnershipUniversity of WarwickCoventryUK,School of Life SciencesUniversity of WarwickCoventryUK
| | - Rebekah A. Jones
- School of Life SciencesUniversity of WarwickCoventryUK,MRC Doctoral Training PartnershipUniversity of WarwickCoventryUK
| | - Holly Shropshire
- BBSRC Midlands Integrative Biosciences Training PartnershipUniversity of WarwickCoventryUK,School of Life SciencesUniversity of WarwickCoventryUK
| | - Isabel Aberdeen
- BBSRC Midlands Integrative Biosciences Training PartnershipUniversity of WarwickCoventryUK,School of Life SciencesUniversity of WarwickCoventryUK
| | | | - Andrew Millard
- Department of Genetics and Genome BiologyUniversity of LeicesterUK
| | - Yin Chen
- School of Life SciencesUniversity of WarwickCoventryUK
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12
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Protective effect of two new nanovaccines against Pseudomonas aeruginosa based on LPS and OPS: A comparison study. Immunobiology 2022; 227:152278. [PMID: 36115097 DOI: 10.1016/j.imbio.2022.152278] [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: 07/16/2022] [Revised: 08/27/2022] [Accepted: 09/05/2022] [Indexed: 11/20/2022]
Abstract
Pseudomonas aeruginosa is one of the most important infectious pathogens in medicine. This bacterium causes various infections, especially in patients with severe burns and people with defective immune systems. The purpose of this study was to develop a nanovaccine based on PLGA nanoparticles and lipopolysaccharide and oligopolysaccharide antigens for appropriate stimulation of the humoral and cellular immune systems against P. aeruginosa. LPS-PLGA and OPS-PLGA conjugates were synthesized using the carbodiimide reaction. The prepared conjugates of as well as the pure antigens of LPS and OPS were injected to BALB/c mice in three periods at 2 week intervals. The ELISA test showed that the IgM, IgA, IgG, IgG1, IgG2b, IgG2a and IgG3 antibodies produced against LPS-PLGA or OPS-PLGA conjugates were tens of times higher than the pure antigens. Also, the opsonophagocytosis test showed that the performance and the effect of produced anti-LPS-PLGA antibodies were higher than other groups. In addition, the mice treated with LPS-PLGA conjugate were more resistant to P. aeruginosa infection than other groups. These findings indicated that LPS and OPS antigens in conjugation with PLGA nanoparticles have the ability to create and effective immunity against P. aeruginosa and LPS-PLGA is more effective than OPS-PLGA.
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13
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Planet PJ. Adaptation and Evolution of Pathogens in the Cystic Fibrosis Lung. J Pediatric Infect Dis Soc 2022; 11:S23-S31. [PMID: 36069898 PMCID: PMC9451014 DOI: 10.1093/jpids/piac073] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 07/11/2022] [Indexed: 02/05/2023]
Abstract
As opposed to acute respiratory infections, the persistent bacterial infections of the lung that characterize cystic fibrosis (CF) provide ample time for bacteria to evolve and adapt. The process of adaptation is recorded in mutations that accumulate over time in the genomes of the infecting bacteria. Some of these mutations lead to obvious phenotypic differences such as antibiotic resistance or the well-known mucoid phenotype of Pseudomonas aeruginosa. Other mutations may be just as important but harder to detect such as increased mutation rates, cell surface changes, and shifts in metabolism and nutrient acquisition. Remarkably, many of the adaptations occur again and again in different patients, signaling that bacteria are adapting to solve specific challenges in the CF respiratory tract. This parallel evolution even extends across distinct bacterial species. This review addresses the bacterial systems that are known to change in long-term CF infections with a special emphasis on cross-species comparisons. Consideration is given to how adaptation may impact health in CF, and the possible evolutionary mechanisms that lead to the repeated parallel adaptations.
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Affiliation(s)
- Paul J Planet
- Corresponding Author: Paul J. Planet, MD, PhD, 3615 Civic Center Blvd, Philadelphia, PA 19104. E-mail:
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14
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Constantino-Teles P, Jouault A, Touqui L, Saliba AM. Role of Host and Bacterial Lipids in Pseudomonas aeruginosa Respiratory Infections. Front Immunol 2022; 13:931027. [PMID: 35860265 PMCID: PMC9289105 DOI: 10.3389/fimmu.2022.931027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/07/2022] [Indexed: 11/13/2022] Open
Abstract
The opportunistic pathogen Pseudomonas aeruginosa is one of the most common agents of respiratory infections and has been associated with high morbidity and mortality rates. The ability of P. aeruginosa to cause severe respiratory infections results from the coordinated action of a variety of virulence factors that promote bacterial persistence in the lungs. Several of these P. aeruginosa virulence mechanisms are mediated by bacterial lipids, mainly lipopolysaccharide, rhamnolipid, and outer membrane vesicles. Other mechanisms arise from the activity of P. aeruginosa enzymes, particularly ExoU, phospholipase C, and lipoxygenase A, which modulate host lipid signaling pathways. Moreover, host phospholipases, such as cPLA2α and sPLA2, are also activated during the infectious process and play important roles in P. aeruginosa pathogenesis. These mechanisms affect key points of the P. aeruginosa-host interaction, such as: i) biofilm formation that contributes to bacterial colonization and survival, ii) invasion of tissue barriers that allows bacterial dissemination, iii) modulation of inflammatory responses, and iv) escape from host defenses. In this mini-review, we present the lipid-based mechanism that interferes with the establishment of P. aeruginosa in the lungs and discuss how bacterial and host lipids can impact the outcome of P. aeruginosa respiratory infections.
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Affiliation(s)
- Pamella Constantino-Teles
- Department of Microbiology, Immunology and Parasitology, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro, Brazil
| | - Albane Jouault
- Sorbonne Université, Centre de Recherche Saint-Antoine, Inserm, Institut Pasteur, Mucoviscidose et Bronchopathies Chroniques, Département Santé Globale, Paris, France
| | - Lhousseine Touqui
- Sorbonne Université, Centre de Recherche Saint-Antoine, Inserm, Institut Pasteur, Mucoviscidose et Bronchopathies Chroniques, Département Santé Globale, Paris, France
| | - Alessandra Mattos Saliba
- Department of Microbiology, Immunology and Parasitology, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro, Brazil
- *Correspondence: Alessandra Mattos Saliba,
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15
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Valvano MA. Remodelling of the Gram-negative bacterial Kdo 2-lipid A and its functional implications. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35394417 DOI: 10.1099/mic.0.001159] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The lipopolysaccharide (LPS) is a characteristic molecule of the outer leaflet of the Gram-negative bacterial outer membrane, which consists of lipid A, core oligosaccharide, and O antigen. The lipid A is embedded in outer membrane and provides an efficient permeability barrier, which is particularly important to reduce the permeability of antibiotics, toxic cationic metals, and antimicrobial peptides. LPS, an important modulator of innate immune responses ranging from localized inflammation to disseminated sepsis, displays a high level of structural and functional heterogeneity, which arise due to regulated differences in the acylation of the lipid A and the incorporation of non-stoichiometric modifications in lipid A and the core oligosaccharide. This review focuses on the current mechanistic understanding of the synthesis and assembly of the lipid A molecule and its most salient non-stoichiometric modifications.
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Affiliation(s)
- Miguel A Valvano
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, BT9 7BL, UK
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16
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Gerster T, Wröbel M, Hofstaedter CE, Schwudke D, Ernst RK, Ranf S, Gisch N. Remodeling of Lipid A in Pseudomonas syringae pv. phaseolicola In Vitro. Int J Mol Sci 2022; 23:1996. [PMID: 35216122 PMCID: PMC8876380 DOI: 10.3390/ijms23041996] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/07/2022] [Accepted: 02/08/2022] [Indexed: 12/24/2022] Open
Abstract
Pseudomonas species infect a variety of organisms, including mammals and plants. Mammalian pathogens of the Pseudomonas family modify their lipid A during host entry to evade immune responses and to create an effective barrier against different environments, for example by removal of primary acyl chains, addition of phosphoethanolamine (P-EtN) to primary phosphates, and hydroxylation of secondary acyl chains. For Pseudomonas syringae pv. phaseolicola (Pph) 1448A, an economically important pathogen of beans, we observed similar lipid A modifications by mass spectrometric analysis. Therefore, we investigated predicted proteomes of various plant-associated Pseudomonas spp. for putative lipid A-modifying proteins using the well-studied mammalian pathogen Pseudomonas aeruginosa as a reference. We generated isogenic mutant strains of candidate genes and analyzed their lipid A. We show that the function of PagL, LpxO, and EptA is generally conserved in Pph 1448A. PagL-mediated de-acylation occurs at the distal glucosamine, whereas LpxO hydroxylates the secondary acyl chain on the distal glucosamine. The addition of P-EtN catalyzed by EptA occurs at both phosphates of lipid A. Our study characterizes lipid A modifications in vitro and provides a useful set of mutant strains relevant for further functional studies on lipid A modifications in Pph 1448A.
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Affiliation(s)
- Tim Gerster
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany;
| | - Michelle Wröbel
- Division of Bioanalytical Chemistry, Priority Area Infections, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany; (M.W.); (D.S.)
| | - Casey E. Hofstaedter
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA; (C.E.H.); (R.K.E.)
| | - Dominik Schwudke
- Division of Bioanalytical Chemistry, Priority Area Infections, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany; (M.W.); (D.S.)
- German Center for Infection Research (DZIF), Thematic Translational Unit Tuberculosis, Partner Site Hamburg-Lübeck-Borstel-Riems, 23845 Borstel, Germany
- Airway Research Center North, Member of the German Center for Lung Research (DZL), Site Research Center Borstel, 23845 Borstel, Germany
| | - Robert K. Ernst
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA; (C.E.H.); (R.K.E.)
| | - Stefanie Ranf
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany;
| | - Nicolas Gisch
- Division of Bioanalytical Chemistry, Priority Area Infections, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany; (M.W.); (D.S.)
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17
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Jeannot K, Hagart K, Dortet L, Kostrzewa M, Filloux A, Plesiat P, Larrouy-Maumus G. Detection of Colistin Resistance in Pseudomonas aeruginosa Using the MALDIxin Test on the Routine MALDI Biotyper Sirius Mass Spectrometer. Front Microbiol 2021; 12:725383. [PMID: 34531843 PMCID: PMC8438524 DOI: 10.3389/fmicb.2021.725383] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 08/05/2021] [Indexed: 12/12/2022] Open
Abstract
Colistin is frequently a last resort treatment for Pseudomonas aeruginosa infections caused by multidrug-resistant (MDR) and extensively drug resistant (XDR) strains, and detection of colistin resistance is essential for the management of infected patients. Therefore, we evaluated the recently developed MALDIxin test for the detection of colistin resistance in P. aeruginosa clinical strains using the routine matrix-assisted laser desorption ionization (MALDI) Biotyper Sirius system. The test is based on the detection by mass spectrometry of modified lipid A by the addition of 4-amino-l-arabinose (l-ara4N) molecules on one or two phosphate groups, in strains resistant to colistin. Overproduction of l-Ara4N molecules is mainly due to the constitutive activation of the histidine kinase (PmrB) or the response regulator (PmrA) following an amino-acid substitution in clinical strains. The performance of the test was determined on a panel of 14 colistin-susceptible and 14 colistin-resistant P. aeruginosa clinical strains, the reference strain PAO1 and positive control mutants PmrB (V28G), PmrB (D172), PhoQ (D240-247), and ParR (M59I). In comparison with the broth microdilution (BMD) method, all the susceptible strains (n=14) and 8/14 colistin-resistant strains were detected in less than 1h, directly on whole bacteria. The remaining resistant strains (n=6) were all detected after a short pre-exposure (4h) to colistin before sample preparation. Validation of the method on a larger panel of strains will be the next step before its use in diagnostics laboratories. Our data showed that the MALDIxin test offers rapid and efficient detection of colistin resistant P. aeruginosa and is thus a valuable diagnostics tool to control the spread of these emerging resistant strains.
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Affiliation(s)
- Katy Jeannot
- UMR 6249 Chrono-Environnement, UFR Sciences Médicales et Pharmaceutiques, University of Bourgogne-Franche Comté, Besançon, France
- French National Reference Centre for Antibiotic Resistance, Besançon, France
- Department of Bacteriology, University Hospital of Besançon, Besançon, France
| | - Katheryn Hagart
- Department of Life Sciences, Faculty of Natural Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Laurent Dortet
- French National Reference Centre for Antibiotic Resistance, Besançon, France
- Department of Bacteriology-Hygiene, Bicêtre Hospital, Assistance Publique – Hôpitaux de Paris, Le Kremlin-Bicêtre, France
- EA7361 “Structure, Dynamic, Function and Expression of Broad Spectrum β-lactamases,” LabEx Lermit, Faculty of Medecine, Paris-Sud University, Le Kremlin-Bicêtre, France
| | | | - Alain Filloux
- Department of Life Sciences, Faculty of Natural Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Patrick Plesiat
- UMR 6249 Chrono-Environnement, UFR Sciences Médicales et Pharmaceutiques, University of Bourgogne-Franche Comté, Besançon, France
- French National Reference Centre for Antibiotic Resistance, Besançon, France
- Department of Bacteriology, University Hospital of Besançon, Besançon, France
| | - Gerald Larrouy-Maumus
- Department of Life Sciences, Faculty of Natural Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
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18
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Augusto LA, Bourgeois-Nicolaos N, Breton A, Barreault S, Alonso EH, Gera S, Faraut-Derouin V, Semaan N, De Luca D, Chaby R, Doucet-Populaire F, Tissières P. Presence of 2-hydroxymyristate on endotoxins is associated with death in neonates with Enterobacter cloacae complex septic shock. iScience 2021; 24:102916. [PMID: 34409274 PMCID: PMC8361193 DOI: 10.1016/j.isci.2021.102916] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 05/11/2021] [Accepted: 07/27/2021] [Indexed: 11/29/2022] Open
Abstract
Enterobacter cloacae complex species are involved in infections among critically ill patients. After a recent E.cloacae outbreak of fulminant neonatal septic shock, we conducted a study to determine whether septic shock severity and its lethal consequence are related to structural features of the endotoxin (lipopolysaccharide [LPS]) of the strains isolated from hospitalized infants and more specifically its lipid A region. It appeared that the LPSs are very heterogeneous, carrying fifteen different molecular species of lipid A. The virulence was correlated with a structural feature identified by matrix-assisted laser desorption ionization–time of flight mass spectrometry and gas chromatography coupled with mass spectrometry: the presence of 2-hydroxymyristic acid as a secondary substituent in lipid A. This is the first published evidence linking LPS structural moiety to neonatal sepsis outcome and opens the possibility of using this fatty acid marker as a detection tool for high-risk patients, which could help reduce their mortality. Fifteen different molecular species of lipid A is found in E. cloacae complex 2-Hydroxymyristate moiety on Lipid A is a virulence marker of the E. cloacae complex Presence of 2-hydroxymyristate is associated with mortality in neonatal sepsis
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Affiliation(s)
- Luis A Augusto
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Nadège Bourgeois-Nicolaos
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.,Department of Bacteriology-Hygiene, AP-HP Paris-Saclay, Hôpital Antoine Béclère, Clamart Cedex, France
| | - Aude Breton
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Simon Barreault
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.,Department of Pediatrics Intensive Care and Neonatal Medicine, AP-HP Université Paris -Saclay, Bicêtre Hospital, Paris, France
| | - Enrique Hernandez Alonso
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Stuti Gera
- Department of Bacteriology-Hygiene, AP-HP Paris-Saclay, Hôpital Antoine Béclère, Clamart Cedex, France
| | - Véronique Faraut-Derouin
- Department of Bacteriology-Hygiene, AP-HP Paris-Saclay, Hôpital Antoine Béclère, Clamart Cedex, France
| | - Nada Semaan
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.,Department of Pediatrics Intensive Care and Neonatal Medicine, AP-HP Université Paris -Saclay, Bicêtre Hospital, Paris, France
| | - Daniele De Luca
- Department of Neonatal Intensive Care, AP-HP Université Paris -Saclay, Hôpital Antoine Béclère, Clamart, France
| | - Richard Chaby
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Florence Doucet-Populaire
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.,Department of Bacteriology-Hygiene, AP-HP Paris-Saclay, Hôpital Antoine Béclère, Clamart Cedex, France
| | - Pierre Tissières
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.,Department of Pediatrics Intensive Care and Neonatal Medicine, AP-HP Université Paris -Saclay, Bicêtre Hospital, Paris, France.,FHU Sepsis, AP-HP/Université Paris-Saclay/Inserm, Le Kremlin-Bicêtre, France
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19
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Specific and Global RNA Regulators in Pseudomonas aeruginosa. Int J Mol Sci 2021; 22:ijms22168632. [PMID: 34445336 PMCID: PMC8395346 DOI: 10.3390/ijms22168632] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/05/2021] [Accepted: 08/08/2021] [Indexed: 01/20/2023] Open
Abstract
Pseudomonas aeruginosa (Pae) is an opportunistic pathogen showing a high intrinsic resistance to a wide variety of antibiotics. It causes nosocomial infections that are particularly detrimental to immunocompromised individuals and to patients suffering from cystic fibrosis. We provide a snapshot on regulatory RNAs of Pae that impact on metabolism, pathogenicity and antibiotic susceptibility. Different experimental approaches such as in silico predictions, co-purification with the RNA chaperone Hfq as well as high-throughput RNA sequencing identified several hundreds of regulatory RNA candidates in Pae. Notwithstanding, using in vitro and in vivo assays, the function of only a few has been revealed. Here, we focus on well-characterized small base-pairing RNAs, regulating specific target genes as well as on larger protein-binding RNAs that sequester and thereby modulate the activity of translational repressors. As the latter impact large gene networks governing metabolism, acute or chronic infections, these protein-binding RNAs in conjunction with their cognate proteins are regarded as global post-transcriptional regulators.
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20
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Recombinant Pseudomonas bio-nanoparticles induce protection against pneumonic Pseudomonas aeruginosa infection. Infect Immun 2021; 89:e0039621. [PMID: 34310892 DOI: 10.1128/iai.00396-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To develop an effective Pseudomonas aeruginosa (PA) outer-membrane-vesicles (OMVs) vaccine, we eliminated multiple virulence factors from a wild-type P. aeruginosa PA103 strain (PA103) to generate a recombinant strain, PA-m14. The PA-m14 strain was tailored with a pSMV83 plasmid encoding the pcrV-hitAT fusion gene to produce OMVs. The recombinant OMVs enclosed increased amounts of PcrV-HitAT bivalent antigen (PH) (termed OMV-PH) and exhibited reduced toxicity compared to the OMVs from PA103. Intramuscular vaccination with OMV-PH from PA-m14(pSMV83) afforded 70% protection against intranasal challenge with 6.5 × 106 CFU (∼30 LD50) of PA103, while immunization using OMVs without the PH antigen (termed OMV-NA) or the PH antigen alone failed to offer effective protection against the same challenge. Further immune analysis showed that the OMV-PH immunization significantly stimulated potent antigen-specific humoral and T-cell (Th1/Th17) responses in comparison to the PH or OMV-NA immunization in mice, which can effectively hinder PA infection. Undiluted anti-sera from OMV-PH-immunized mice displayed significant opsonophagocytic killing of WT PA103 compared to antisera from PH antigen- or OMV-NA-immunized mice. Moreover, the OMV-PH immunization afforded significant antibody-indentpednet cross-protection to mice against PAO1 and a clinical isolate AMC-PA10 strains. Collectively, the recombinant PA OMV delivering the PH bivalent antigen exhibits high immunogenicity and would be a promising next-generation vaccine candidate against PA infection.
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21
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Pseudomonas aeruginosa adaptation and evolution in patients with cystic fibrosis. Nat Rev Microbiol 2021; 19:331-342. [PMID: 33214718 DOI: 10.1038/s41579-020-00477-5] [Citation(s) in RCA: 204] [Impact Index Per Article: 68.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/09/2020] [Indexed: 01/29/2023]
Abstract
Intense genome sequencing of Pseudomonas aeruginosa isolates from cystic fibrosis (CF) airways has shown inefficient eradication of the infecting bacteria, as well as previously undocumented patient-to-patient transmission of adapted clones. However, genome sequencing has limited potential as a predictor of chronic infection and of the adaptive state during infection, and thus there is increasing interest in linking phenotypic traits to the genome sequences. Phenotypic information ranges from genome-wide transcriptomic analysis of patient samples to determination of more specific traits associated with metabolic changes, stress responses, antibiotic resistance and tolerance, biofilm formation and slow growth. Environmental conditions in the CF lung shape both genetic and phenotypic changes of P. aeruginosa during infection. In this Review, we discuss the adaptive and evolutionary trajectories that lead to early diversification and late convergence, which enable P. aeruginosa to succeed in this niche, and we point out how knowledge of these biological features may be used to guide diagnosis and therapy.
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22
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Avila-Calderón ED, Ruiz-Palma MDS, Aguilera-Arreola MG, Velázquez-Guadarrama N, Ruiz EA, Gomez-Lunar Z, Witonsky S, Contreras-Rodríguez A. Outer Membrane Vesicles of Gram-Negative Bacteria: An Outlook on Biogenesis. Front Microbiol 2021; 12:557902. [PMID: 33746909 PMCID: PMC7969528 DOI: 10.3389/fmicb.2021.557902] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 02/04/2021] [Indexed: 12/14/2022] Open
Abstract
Outer membrane vesicles (OMVs) from Gram-negative bacteria were first described more than 50 years ago. However, the molecular mechanisms involved in biogenesis began to be studied only in the last few decades. Presently, the biogenesis and molecular mechanisms for their release are not completely known. This review covers the most recent information on cellular components involved in OMV biogenesis, such as lipoproteins and outer membrane proteins, lipopolysaccharide, phospholipids, quorum-sensing molecules, and flagella.
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Affiliation(s)
- Eric Daniel Avila-Calderón
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México City, Mexico.,Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, CINVESTAV-IPN, México City, Mexico
| | - María Del Socorro Ruiz-Palma
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México City, Mexico.,División Químico Biológicas, Universidad Tecnológica de Tecámac, Tecámac, Mexico
| | - Ma Guadalupe Aguilera-Arreola
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México City, Mexico
| | - Norma Velázquez-Guadarrama
- Unidad de Investigación en enfermedades infecciosas, Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico
| | - Enrico A Ruiz
- Departamento de Zoología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México City, Mexico
| | - Zulema Gomez-Lunar
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México City, Mexico
| | - Sharon Witonsky
- Center for One Health Research, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States.,Large Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, United States
| | - Araceli Contreras-Rodríguez
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México City, Mexico
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23
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Wolter DJ, Scott A, Armbruster CR, Whittington D, Edgar JS, Qin X, Buccat AM, McNamara S, Blackledge M, Waalkes A, Salipante SJ, Ernst RK, Hoffman LR. Repeated isolation of an antibiotic-dependent and temperature-sensitive mutant of Pseudomonas aeruginosa from a cystic fibrosis patient. J Antimicrob Chemother 2021; 76:616-625. [PMID: 33259594 DOI: 10.1093/jac/dkaa482] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 10/02/2020] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Bacteria adapt to survive and grow in different environments. Genetic mutations that promote bacterial survival under harsh conditions can also restrict growth. The causes and consequences of these adaptations have important implications for diagnosis, pathogenesis, and therapy. OBJECTIVES We describe the isolation and characterization of an antibiotic-dependent, temperature-sensitive Pseudomonas aeruginosa mutant chronically infecting the respiratory tract of a cystic fibrosis (CF) patient, underscoring the clinical challenges bacterial adaptations can present. METHODS Respiratory samples collected from a CF patient during routine care were cultured for standard pathogens. P. aeruginosa isolates recovered from samples were analysed for in vitro growth characteristics, antibiotic susceptibility, clonality, and membrane phospholipid and lipid A composition. Genetic mutations were identified by whole genome sequencing. RESULTS P. aeruginosa isolates collected over 5 years from respiratory samples of a CF patient frequently harboured a mutation in phosphatidylserine decarboxylase (psd), encoding an enzyme responsible for phospholipid synthesis. This mutant could only grow at 37°C when in the presence of supplemented magnesium, glycerol, or, surprisingly, the antibiotic sulfamethoxazole, which the source patient had repeatedly received. Of concern, this mutant was not detectable on standard selective medium at 37°C. This growth defect correlated with alterations in membrane phospholipid and lipid A content. CONCLUSIONS A P. aeruginosa mutant chronically infecting a CF patient exhibited dependence on sulphonamides and would likely evade detection using standard clinical laboratory methods. The diagnostic and therapeutic challenges presented by this mutant highlight the complex interplay between bacterial adaptation, antibiotics, and laboratory practices, during chronic bacterial infections.
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Affiliation(s)
- Daniel J Wolter
- Department of Pediatrics, University of Washington, Seattle, WA, USA.,Seattle Children's Hospital, Seattle, WA, USA
| | - Alison Scott
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, USA
| | | | - Dale Whittington
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, USA
| | - John S Edgar
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, USA
| | - Xuan Qin
- Seattle Children's Hospital, Seattle, WA, USA
| | | | | | | | - Adam Waalkes
- Department of Laboratory Medicine, University of Washington, Seattle, WA, USA
| | - Stephen J Salipante
- Department of Laboratory Medicine, University of Washington, Seattle, WA, USA
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, USA
| | - Lucas R Hoffman
- Department of Pediatrics, University of Washington, Seattle, WA, USA.,Seattle Children's Hospital, Seattle, WA, USA.,Department of Microbiology, University of Washington, Seattle, WA, USA
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24
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Horne JE, Brockwell DJ, Radford SE. Role of the lipid bilayer in outer membrane protein folding in Gram-negative bacteria. J Biol Chem 2020; 295:10340-10367. [PMID: 32499369 PMCID: PMC7383365 DOI: 10.1074/jbc.rev120.011473] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 06/03/2020] [Indexed: 01/09/2023] Open
Abstract
β-Barrel outer membrane proteins (OMPs) represent the major proteinaceous component of the outer membrane (OM) of Gram-negative bacteria. These proteins perform key roles in cell structure and morphology, nutrient acquisition, colonization and invasion, and protection against external toxic threats such as antibiotics. To become functional, OMPs must fold and insert into a crowded and asymmetric OM that lacks much freely accessible lipid. This feat is accomplished in the absence of an external energy source and is thought to be driven by the high thermodynamic stability of folded OMPs in the OM. With such a stable fold, the challenge that bacteria face in assembling OMPs into the OM is how to overcome the initial energy barrier of membrane insertion. In this review, we highlight the roles of the lipid environment and the OM in modulating the OMP-folding landscape and discuss the factors that guide folding in vitro and in vivo We particularly focus on the composition, architecture, and physical properties of the OM and how an understanding of the folding properties of OMPs in vitro can help explain the challenges they encounter during folding in vivo Current models of OMP biogenesis in the cellular environment are still in flux, but the stakes for improving the accuracy of these models are high. OMP folding is an essential process in all Gram-negative bacteria, and considering the looming crisis of widespread microbial drug resistance it is an attractive target. To bring down this vital OMP-supported barrier to antibiotics, we must first understand how bacterial cells build it.
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Affiliation(s)
- Jim E Horne
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - David J Brockwell
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
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25
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Mues N, Chu HW. Out-Smarting the Host: Bacteria Maneuvering the Immune Response to Favor Their Survival. Front Immunol 2020; 11:819. [PMID: 32477341 PMCID: PMC7235365 DOI: 10.3389/fimmu.2020.00819] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 04/09/2020] [Indexed: 12/29/2022] Open
Abstract
Bacteria adapt themselves to various environmental conditions in nature, which can lead to bacterial adaptation and persistence in the host as commensals or pathogens. In healthy individuals, host defense mechanisms prevent the opportunistic bacteria/commensals from becoming a pathological infection. However, certain pathological conditions can impair normal defense barriers leading to bacterial survival and persistence. Under pathological conditions such as chronic lung inflammation, bacteria employ various mechanisms from structural changes to protease secretion to manipulate and evade the host immune response and create a niche permitting commensal bacteria to thrive into infections. Therefore, understanding the mechanisms by which pathogenic bacteria survive in the host tissues and organs may offer new strategies to overcome persistent bacterial infections. In this review, we will discuss and highlight the complex interactions between airway pathogenic bacteria and immune responses in several major chronic inflammatory diseases such as asthma and chronic obstructive pulmonary disease (COPD).
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Affiliation(s)
- Nastaran Mues
- Department of Medicine, National Jewish Health, Denver, CO, United States
| | - Hong Wei Chu
- Department of Medicine, National Jewish Health, Denver, CO, United States
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26
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The Role of Pseudomonas aeruginosa Lipopolysaccharide in Bacterial Pathogenesis and Physiology. Pathogens 2019; 9:pathogens9010006. [PMID: 31861540 PMCID: PMC7168646 DOI: 10.3390/pathogens9010006] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 12/15/2019] [Accepted: 12/17/2019] [Indexed: 12/13/2022] Open
Abstract
The major constituent of the outer membrane of Gram-negative bacteria is lipopolysaccharide (LPS), which is comprised of lipid A, core oligosaccharide, and O antigen, which is a long polysaccharide chain extending into the extracellular environment. Due to the localization of LPS, it is a key molecule on the bacterial cell wall that is recognized by the host to deploy an immune defence in order to neutralize invading pathogens. However, LPS also promotes bacterial survival in a host environment by protecting the bacteria from these threats. This review explores the relationship between the different LPS glycoforms of the opportunistic pathogen Pseudomonas aeruginosa and the ability of this organism to cause persistent infections, especially in the genetic disease cystic fibrosis. We also discuss the role of LPS in facilitating biofilm formation, antibiotic resistance, and how LPS may be targeted by new antimicrobial therapies.
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27
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Lo Sciuto A, Cervoni M, Stefanelli R, Spinnato MC, Di Giamberardino A, Mancone C, Imperi F. Genetic Basis and Physiological Effects of Lipid A Hydroxylation in Pseudomonas aeruginosa PAO1. Pathogens 2019; 8:E291. [PMID: 31835493 PMCID: PMC6963906 DOI: 10.3390/pathogens8040291] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 12/03/2019] [Accepted: 12/08/2019] [Indexed: 01/09/2023] Open
Abstract
Modifications of the lipid A moiety of lipopolysaccharide influence the physicochemical properties of the outer membrane of Gram-negative bacteria. Some bacteria produce lipid A with a single hydroxylated secondary acyl chain. This hydroxylation is catalyzed by the dioxygenase LpxO, and is important for resistance to cationic antimicrobial peptides (e.g., polymyxins), survival in human blood, and pathogenicity in animal models. The lipid A of the human pathogen Pseudomonas aeruginosa can be hydroxylated in both secondary acyl chains, but the genetic basis and physiological role of these hydroxylations are still unknown. Through the generation of single and double deletion mutants in the lpxO1 and lpxO2 homologs of P. aeruginosa PAO1 and lipid A analysis by mass spectrometry, we demonstrate that both LpxO1 and LpxO2 are responsible for lipid A hydroxylation, likely acting on different secondary acyl chains. Lipid A hydroxylation does not appear to affect in vitro growth, cell wall stability, and resistance to human blood or antibiotics in P. aeruginosa. In contrast, it is required for infectivity in the Galleria mellonella infection model, without relevantly affecting in vivo persistence. Overall, these findings suggest a role for lipid A hydroxylation in P. aeruginosa virulence that could not be directly related to outer membrane integrity.
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Affiliation(s)
| | - Matteo Cervoni
- Department of Science, Roma Tre University, 00146 Roma, Italy (M.C.S.)
| | - Roberta Stefanelli
- Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, Laboratory affiliated to Istituto Pasteur Italia–Fondazione Cenci Bolognetti, 00185 Roma, Italy;
| | | | | | - Carmine Mancone
- Department of Molecular Medicine, Sapienza University of Rome, 00185 Roma, Italy; (A.D.G.); (C.M.)
| | - Francesco Imperi
- Department of Science, Roma Tre University, 00146 Roma, Italy (M.C.S.)
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28
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Temperature-dependent regulation of the Escherichia coli lpxT gene. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:786-795. [DOI: 10.1016/j.bbagrm.2019.06.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 06/28/2019] [Accepted: 06/30/2019] [Indexed: 01/11/2023]
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29
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Abstract
The current work by Jain et al. (S. Jain, A. M. Chang, M. Singh, J. S. McLean, et al., J Bacteriol 201:e00683-18, 2019, https://doi.org/10.1128/JB.00683-18) reports the cloning of the lipid A deacylase gene of Porphyromonas gingivalis and the phenotypic characterization of the enzyme. Attempts to clone the gene and thus provide proof of the existence of this enzyme had gone on for 2 decades. The enzyme is central to the bacterium's ability to modify and tailor the structure of its lipid A, changing a lipid A that is a moderate Toll-like receptor 4 (TLR4) agonist to an antagonist or silencer and thereby potentially changing the course of infection.
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Affiliation(s)
- Ann Progulske-Fox
- Center for Molecular Microbiology and Department of Oral Biology, University of Florida, Gainesville, Florida, USA
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30
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Identification of PGN_1123 as the Gene Encoding Lipid A Deacylase, an Enzyme Required for Toll-Like Receptor 4 Evasion, in Porphyromonas gingivalis. J Bacteriol 2019; 201:JB.00683-18. [PMID: 30782639 DOI: 10.1128/jb.00683-18] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 02/12/2019] [Indexed: 01/09/2023] Open
Abstract
Removal of one acyl chain from bacterial lipid A by deacylase activity is a mechanism used by many pathogenic bacteria to evade the host's Toll-like receptor 4 (TLR4)-mediated innate immune response. In Porphyromonas gingivalis, a periodontal pathogen, lipid A deacylase activity converts a majority of the initially synthesized penta-acylated lipid A, a TLR4 agonist, to tetra-acylated structures, which effectively evade TLR4 sensing by being either inert or antagonistic at TLR4. In this paper, we report successful identification of the gene that encodes the P. gingivalis lipid A deacylase enzyme. This gene, PGN_1123 in P. gingivalis 33277, is highly conserved within P. gingivalis, and putative orthologs are phylogenetically restricted to the Bacteroidetes phylum. Lipid A of ΔPGN_1123 mutants is penta-acylated and devoid of tetra-acylated structures, and the mutant strain provokes a strong TLR4-mediated proinflammatory response, in contrast to the negligible response elicited by wild-type P. gingivalis Heterologous expression of PGN_1123 in Bacteroides thetaiotaomicron promoted lipid A deacylation, confirming that PGN_1123 encodes the lipid A deacylase enzyme.IMPORTANCE Periodontitis, commonly referred to as gum disease, is a chronic inflammatory condition that affects a large proportion of the population. Porphyromonas gingivalis is a bacterium closely associated with periodontitis, although how and if it is a cause for the disease are not known. It has a formidable capacity to dampen the host's innate immune response, enabling its persistence in diseased sites and triggering microbial dysbiosis in animal models of infection. P. gingivalis is particularly adept at evading the host's TLR4-mediated innate immune response by modifying the structure of lipid A, the TLR4 ligand. In this paper, we report identification of the gene encoding lipid A deacylase, a key enzyme that modifies lipid A to TLR4-evasive structures.
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31
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Kutschera A, Dawid C, Gisch N, Schmid C, Raasch L, Gerster T, Schäffer M, Smakowska-Luzan E, Belkhadir Y, Vlot AC, Chandler CE, Schellenberger R, Schwudke D, Ernst RK, Dorey S, Hückelhoven R, Hofmann T, Ranf S. Bacterial medium-chain 3-hydroxy fatty acid metabolites trigger immunity in
Arabidopsis
plants. Science 2019; 364:178-181. [DOI: 10.1126/science.aau1279] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 01/02/2019] [Accepted: 03/12/2019] [Indexed: 04/09/2023]
Abstract
A fatty acid triggers immune responses
Plants and animals respond to the microbial communities around them, whether in antagonistic or mutualistic ways. Some of these interactions are mediated by lipopolysaccharide—a large, complex, and irregular molecule on the surface of most Gram-negative bacteria. Studying the small mustard plant
Arabidopsis
, Kutschera
et al.
identified a 3-hydroxydecanoyl chain as the structural element sensed by the plant's lectin receptor kinase. Indeed, synthetic 3-hydroxydecanoic acid alone was sufficient to produce a response. A small microbial metabolite may thus suffice to trigger immune responses.
Science
, this issue p.
178
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Affiliation(s)
- Alexander Kutschera
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany
| | - Corinna Dawid
- Chair of Food Chemistry and Molecular Sensory Science, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany
| | - Nicolas Gisch
- Division of Bioanalytical Chemistry, Priority Area Infections, Research Center Borstel, Leibniz Lung Center, Parkallee 1-40, 23845 Borstel, Germany
| | - Christian Schmid
- Chair of Food Chemistry and Molecular Sensory Science, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany
| | - Lars Raasch
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany
| | - Tim Gerster
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany
| | - Milena Schäffer
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany
| | - Elwira Smakowska-Luzan
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna Biocenter, 1030 Vienna, Austria
| | - Youssef Belkhadir
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna Biocenter, 1030 Vienna, Austria
| | - A. Corina Vlot
- Helmholtz Zentrum Muenchen, Department of Environmental Science, Institute of Biochemical Plant Pathology, 85764 Neuherberg, Germany
| | - Courtney E. Chandler
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Romain Schellenberger
- RIBP-EA 4707, SFR Condorcet-FR CNRS 3417, University of Reims Champagne-Ardenne, 51100 Reims, France
| | - Dominik Schwudke
- Division of Bioanalytical Chemistry, Priority Area Infections, Research Center Borstel, Leibniz Lung Center, Parkallee 1-40, 23845 Borstel, Germany
| | - Robert K. Ernst
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Stéphan Dorey
- RIBP-EA 4707, SFR Condorcet-FR CNRS 3417, University of Reims Champagne-Ardenne, 51100 Reims, France
| | - Ralph Hückelhoven
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany
| | - Thomas Hofmann
- Chair of Food Chemistry and Molecular Sensory Science, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany
| | - Stefanie Ranf
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising-Weihenstephan, Germany
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32
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Moosová Z, Šindlerová L, Ambrůzová B, Ambrožová G, Vašíček O, Velki M, Babica P, Kubala L. Lipopolysaccharides from Microcystis Cyanobacteria-Dominated Water Bloom and from Laboratory Cultures Trigger Human Immune Innate Response. Toxins (Basel) 2019; 11:toxins11040218. [PMID: 30978967 PMCID: PMC6520794 DOI: 10.3390/toxins11040218] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 03/27/2019] [Accepted: 04/09/2019] [Indexed: 12/20/2022] Open
Abstract
Massive toxic blooms of cyanobacteria represent a major threat to water supplies worldwide. Here, the biological activities of lipopolysaccharide (LPS) isolated from Microcystis aeruginosa, the most prominent cyanobacteria in water bloom, were studied. LPS was isolated from complex environmental water bloom samples dominated by M. aeruginosa, and from laboratory cultures of non-axenic as well as axenic M. aeruginosa strains PCC7806 and HAMBI/UHCC130. Employing human blood-based in vitro tests, the LPS isolated from complex water bloom revealed the priming of both major blood phagocyte population monocytes and polymorphonuclear leukocytes documented by the increased surface expression of CD11b and CD66b. This was accompanied by a water bloom LPS-mediated dose-dependent induction of tumor necrosis factor α, interleukin-1β, and interleukin-6 production. In accordance with its priming effects, water bloom LPS induced significant activation of p38 and ERK1/2 kinases, as well as NF-κB phosphorylation, in isolated polymorphonuclear leukocytes. Interestingly, the pro-inflammatory potential of LPS from the axenic strain of M. aeruginosa was not lower compared to that of LPS isolated from non-axenic strains. In contrast to the biological activity, water bloom LPS revealed almost twice higher pyrogenicity levels compared to Escherichia coli LPS, as analyzed by the PyroGene test. Moreover, LPS from the non-axenic culture exhibited higher endotoxin activity in comparison to LPS from axenic strains. Taking the above findings together, M. aeruginosa LPS can contribute to the health risks associated with contamination by complex water bloom mass.
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Affiliation(s)
- Zdena Moosová
- Department of Biophysics of Immune System, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61265 Brno, Czech Republic.
- RECETOX, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic.
| | - Lenka Šindlerová
- Department of Biophysics of Immune System, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61265 Brno, Czech Republic.
- RECETOX, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic.
| | - Barbora Ambrůzová
- Department of Biophysics of Immune System, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61265 Brno, Czech Republic.
| | - Gabriela Ambrožová
- Department of Biophysics of Immune System, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61265 Brno, Czech Republic.
| | - Ondřej Vašíček
- Department of Biophysics of Immune System, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61265 Brno, Czech Republic.
- Institute of Experimental Biology, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic.
| | - Mirna Velki
- Department of Biology, Josip Juraj Strossmayer University of Osijek, 31000 Osijek, Croatia.
| | - Pavel Babica
- RECETOX, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic.
| | - Lukáš Kubala
- Department of Biophysics of Immune System, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61265 Brno, Czech Republic.
- Institute of Experimental Biology, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic.
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33
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Updates on the pathogenicity status of Pseudomonas aeruginosa. Drug Discov Today 2019; 24:350-359. [DOI: 10.1016/j.drudis.2018.07.003] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/03/2018] [Accepted: 07/16/2018] [Indexed: 01/06/2023]
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34
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Faure E, Kwong K, Nguyen D. Pseudomonas aeruginosa in Chronic Lung Infections: How to Adapt Within the Host? Front Immunol 2018; 9:2416. [PMID: 30405616 PMCID: PMC6204374 DOI: 10.3389/fimmu.2018.02416] [Citation(s) in RCA: 126] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 10/01/2018] [Indexed: 01/29/2023] Open
Abstract
Bacteria that readily adapt to different natural environments, can also exploit this versatility upon infection of the host to persist. Pseudomonas aeruginosa, a ubiquitous Gram-negative bacterium, is harmless to healthy individuals, and yet a formidable opportunistic pathogen in compromised hosts. When pathogenic, P. aeruginosa causes invasive and highly lethal disease in certain compromised hosts. In others, such as individuals with the genetic disease cystic fibrosis, this pathogen causes chronic lung infections which persist for decades. During chronic lung infections, P. aeruginosa adapts to the host environment by evolving toward a state of reduced bacterial invasiveness that favors bacterial persistence without causing overwhelming host injury. Host responses to chronic P. aeruginosa infections are complex and dynamic, ranging from vigorous activation of innate immune responses that are ineffective at eradicating the infecting bacteria, to relative host tolerance and dampened activation of host immunity. This review will examine how P. aeruginosa subverts host defenses and modulates immune and inflammatory responses during chronic infection. This dynamic interplay between host and pathogen is a major determinant in the pathogenesis of chronic P. aeruginosa lung infections.
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Affiliation(s)
- Emmanuel Faure
- Department of Medicine, McGill University, Montreal, QC, Canada
- Research Institute of the McGill University Health Center, Montreal, QC, Canada
| | - Kelly Kwong
- Department of Medicine, McGill University, Montreal, QC, Canada
- Research Institute of the McGill University Health Center, Montreal, QC, Canada
| | - Dao Nguyen
- Department of Medicine, McGill University, Montreal, QC, Canada
- Research Institute of the McGill University Health Center, Montreal, QC, Canada
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35
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Wang S, Gao J, Wang Z. Outer membrane vesicles for vaccination and targeted drug delivery. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2018; 11:e1523. [PMID: 29701017 DOI: 10.1002/wnan.1523] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/22/2018] [Accepted: 03/23/2018] [Indexed: 12/17/2022]
Abstract
Extracellular vesicles (EVs) are cell membrane-derived compartments that spontaneously secrete from a wide range of cells and tissues. EVs have shown to be the carriers in delivering drugs and small interfering RNA. Among EVs, bacterial outer membrane vesicles (OMVs) recently have gained the interest in vaccine development and targeted drug delivery. In this review, we summarize the current discoveries of OMVs and their functions. In particular, we focus on the biogenesis of OMVs and their functions in bacterial virulence and pathogenesis. Furthermore, we discuss the applications of OMVs in vaccination and targeted drug delivery. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies Biology-Inspired Nanomaterials > Lipid-Based Structures.
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Affiliation(s)
- Sihan Wang
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, Washington
| | - Jin Gao
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, Washington
| | - Zhenjia Wang
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, Washington
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36
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Han ML, Velkov T, Zhu Y, Roberts KD, Le Brun AP, Chow SH, Gutu AD, Moskowitz SM, Shen HH, Li J. Polymyxin-Induced Lipid A Deacylation in Pseudomonas aeruginosa Perturbs Polymyxin Penetration and Confers High-Level Resistance. ACS Chem Biol 2018; 13:121-130. [PMID: 29182311 DOI: 10.1021/acschembio.7b00836] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Polymyxins are last-line antibiotics against life-threatening multidrug-resistant Gram-negative bacteria. Unfortunately, polymyxin resistance is increasingly reported, leaving a total lack of therapies. Using lipidomics and transcriptomics, we discovered that polymyxin B induced lipid A deacylation via pagL in both polymyxin-resistant and -susceptible Pseudomonas aeruginosa. Our results demonstrated that the deacylation of lipid A is an "innate immunity" response to polymyxins and a key compensatory mechanism to the aminoarabinose modification to confer high-level polymyxin resistance in P. aeruginosa. Furthermore, cutting-edge neutron reflectometry studies revealed that an assembled outer membrane (OM) with the less hydrophobic penta-acylated lipid A decreased polymyxin B penetration, compared to the hexa-acylated form. Polymyxin analogues with enhanced hydrophobicity displayed superior penetration into the tail regions of the penta-acylated lipid A OM. Our findings reveal a previously undiscovered mechanism of polymyxin resistance, wherein polymyxin-induced lipid A remodeling affects the OM packing and hydrophobicity, perturbs polymyxin penetration, and thereby confers high-level resistance.
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Affiliation(s)
- Mei-Ling Han
- Monash
Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville, Victoria 3052, Australia
- Monash
Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Tony Velkov
- Monash
Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville, Victoria 3052, Australia
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Yan Zhu
- Monash
Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Kade D. Roberts
- Monash
Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville, Victoria 3052, Australia
| | - Anton P. Le Brun
- Australian
Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee
DC, New South Wales 2232, Australia
| | - Seong Hoong Chow
- Monash
Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Alina D. Gutu
- Department
of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts United States
| | | | - Hsin-Hui Shen
- Monash
Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
- Department
of Materials Science and Engineering, Faculty of Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Jian Li
- Monash
Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
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Zhang YF, Han K, Chandler CE, Tjaden B, Ernst RK, Lory S. Probing the sRNA regulatory landscape of P. aeruginosa: post-transcriptional control of determinants of pathogenicity and antibiotic susceptibility. Mol Microbiol 2017; 106:919-937. [PMID: 28976035 PMCID: PMC5738928 DOI: 10.1111/mmi.13857] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2017] [Indexed: 01/01/2023]
Abstract
During environmental adaptation bacteria use small regulatory RNAs (sRNAs) to repress or activate expression of a large fraction of their proteome. We extended the use of the in vivo RNA proximity ligation method toward probing global sRNA interactions with their targets in Pseudomonas aeruginosa and verified the method with a known regulon controlled by the PrrF1 sRNA. We also identified two sRNAs (Sr0161 and ErsA) that interact with the mRNA encoding the major porin OprD responsible for the uptake of carbapenem antibiotics. These two sRNAs base pair with the 5' UTR of oprD leading to increase in resistance of the bacteria to meropenem. Additional proximity ligation experiments and enrichment for Sr0161 targets identified the mRNA for the regulator of type III secretion system. Interaction between the exsA mRNA and Sr0161 leads to a block in the synthesis of a component of the T3SS apparatus and an effector. Another sRNA, Sr006, positively regulates, without Hfq, the expression of PagL, an enzyme responsible for deacylation of lipid A, reducing its pro-inflammatory property and resulting in polymyxin resistance. Therefore, an analysis of global sRNA-mRNA interactions can lead to discoveries of novel pathways controlling gene expression that are likely integrated into larger regulatory networks.
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Affiliation(s)
- Yi-Fan Zhang
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, USA
- Harvard School of Dental Medicine, Boston, Massachusetts, USA
| | - Kook Han
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Courtney E. Chandler
- Department of Microbial Pathogenesis, University of Maryland – Baltimore, School of Dentistry, Baltimore, Maryland, USA
| | - Brian Tjaden
- Computer Science Department, Wellesley College, Wellesley, Massachusetts, USA
| | - Robert K. Ernst
- Department of Microbial Pathogenesis, University of Maryland – Baltimore, School of Dentistry, Baltimore, Maryland, USA
| | - Stephen Lory
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, USA
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Guilbaud M, Bruzaud J, Bouffartigues E, Orange N, Guillot A, Aubert-Frambourg A, Monnet V, Herry JM, Chevalier S, Bellon-Fontaine MN. Proteomic Response of Pseudomonas aeruginosa PAO1 Adhering to Solid Surfaces. Front Microbiol 2017; 8:1465. [PMID: 28824592 PMCID: PMC5541441 DOI: 10.3389/fmicb.2017.01465] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 07/20/2017] [Indexed: 12/12/2022] Open
Abstract
Pseudomonas aeruginosa is a pathogenic micro-organism responsible for many hospital-acquired infections. It is able to adhere to solid surfaces and develop an immobilized community or so-called biofilm. Many studies have been focusing on the use of specific materials to prevent the formation of these biofilms, but the reactivity of the bacteria in contact to surfaces remains unknown. The aim of this study was to evaluate the impact of the abiotic surface on the physiology of adherent bacteria. Three different materials, stainless steel (SS), glass (G), and polystyrene (PS) that were relevant to industrial or medical environments were characterized at the physicochemical level in terms of their hydrophobicity and roughness. We showed that SS was moderately hydrophilic and rough, potentially containing crevices, G was hydrophilic and smooth while PS was hydrophobic and smooth. We further showed that P. aeruginosa cells were more likely able to adhere to SS and G rather than PS surfaces under our experimental conditions. The physiological response of P. aeruginosa when adhering to each of these materials was then evaluated by global proteomic analysis. The abundance of 70 proteins was shown to differ between the materials suggesting that their abundance was modified as a function of the material to which bacteria adhered. Our data lead to enabling the identification of abundance patterns that appeared to be specific to a given surface. Taken together, our data showed that P. aeruginosa is capable of sensing and responding to a surface probably via specific programmes to adapt its physiological response accordingly.
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Affiliation(s)
- Morgan Guilbaud
- Micalis Institute, INRA, AgroParisTech, Université Paris-SaclayJouy-en-Josas, France
| | - Jérôme Bruzaud
- Micalis Institute, INRA, AgroParisTech, Université Paris-SaclayJouy-en-Josas, France
| | - Emeline Bouffartigues
- Laboratoire de Microbiologie, Signaux et Microenvironnement, Normandie Université, Université de Rouen-NormandieRouen, France
| | - Nicole Orange
- Laboratoire de Microbiologie, Signaux et Microenvironnement, Normandie Université, Université de Rouen-NormandieRouen, France
| | - Alain Guillot
- Micalis Institute, INRA, AgroParisTech, Université Paris-SaclayJouy-en-Josas, France
| | - Anne Aubert-Frambourg
- Micalis Institute, INRA, AgroParisTech, Université Paris-SaclayJouy-en-Josas, France
| | - Véronique Monnet
- Micalis Institute, INRA, AgroParisTech, Université Paris-SaclayJouy-en-Josas, France
| | - Jean-Marie Herry
- Micalis Institute, INRA, AgroParisTech, Université Paris-SaclayJouy-en-Josas, France
| | - Sylvie Chevalier
- Laboratoire de Microbiologie, Signaux et Microenvironnement, Normandie Université, Université de Rouen-NormandieRouen, France
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Structural Modification of Lipopolysaccharide Conferred by mcr-1 in Gram-Negative ESKAPE Pathogens. Antimicrob Agents Chemother 2017; 61:AAC.00580-17. [PMID: 28373195 PMCID: PMC5444183 DOI: 10.1128/aac.00580-17] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 03/31/2017] [Indexed: 11/20/2022] Open
Abstract
mcr-1 was initially reported as the first plasmid-mediated colistin resistance gene in clinical isolates of Escherichia coli and Klebsiella pneumoniae in China and has subsequently been identified worldwide in various species of the family Enterobacteriaceaemcr-1 encodes a phosphoethanolamine transferase, and its expression has been shown to generate phosphoethanolamine-modified bis-phosphorylated hexa-acylated lipid A in E. coli Here, we investigated the effects of mcr-1 on colistin susceptibility and on lipopolysaccharide structures in laboratory and clinical strains of the Gram-negative ESKAPE (Enterococcus faecium, Staphylococcus aureus, K. pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens, which are often treated clinically by colistin. The effects of mcr-1 on colistin resistance were determined using MIC assays of laboratory and clinical strains of E. coli, K. pneumoniae, A. baumannii, and P. aeruginosa Lipid A structural changes resulting from MCR-1 were analyzed by mass spectrometry. The introduction of mcr-1 led to colistin resistance in E. coli, K. pneumoniae, and A. baumannii but only moderately reduced susceptibility in P. aeruginosa Phosphoethanolamine modification of lipid A was observed consistently for all four species. These findings highlight the risk of colistin resistance as a consequence of mcr-1 expression among ESKAPE pathogens, especially in K. pneumoniae and A. baumannii Furthermore, the observation that lipid A structures were modified despite only modest increases in colistin MICs in some instances suggests more sophisticated surveillance methods may need to be developed to track the dissemination of mcr-1 or plasmid-mediated phosphoethanolamine transferases in general.
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Molecular Epidemiology of Mutations in Antimicrobial Resistance Loci of Pseudomonas aeruginosa Isolates from Airways of Cystic Fibrosis Patients. Antimicrob Agents Chemother 2016; 60:6726-6734. [PMID: 27572404 DOI: 10.1128/aac.00724-16] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 08/23/2016] [Indexed: 01/30/2023] Open
Abstract
The chronic airway infections with Pseudomonas aeruginosa in people with cystic fibrosis (CF) are treated with aerosolized antibiotics, oral fluoroquinolones, and/or intravenous combination therapy with aminoglycosides and β-lactam antibiotics. An international strain collection of 361 P. aeruginosa isolates from 258 CF patients seen at 30 CF clinics was examined for mutations in 17 antimicrobial susceptibility and resistance loci that had been identified as hot spots of mutation by genome sequencing of serial isolates from a single CF clinic. Combinatorial amplicon sequencing of pooled PCR products identified 1,112 sequence variants that were not present in the genomes of representative strains of the 20 most common clones of the global P. aeruginosa population. A high frequency of singular coding variants was seen in spuE, mexA, gyrA, rpoB, fusA1, mexZ, mexY, oprD, ampD, parR, parS, and envZ (amgS), reflecting the pressure upon P. aeruginosa in lungs of CF patients to generate novel protein variants. The proportion of nonneutral amino acid exchanges was high. Of the 17 loci, mexA, mexZ, and pagL were most frequently affected by independent stop mutations. Private and de novo mutations seem to play a pivotal role in the response of P. aeruginosa populations to the antimicrobial load and the individual CF host.
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41
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SenGupta S, Hittle LE, Ernst RK, Uriarte SM, Mitchell TC. A Pseudomonas aeruginosa hepta-acylated lipid A variant associated with cystic fibrosis selectively activates human neutrophils. J Leukoc Biol 2016; 100:1047-1059. [PMID: 27538572 DOI: 10.1189/jlb.4vma0316-101r] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 07/20/2016] [Indexed: 12/12/2022] Open
Abstract
Pseudomonas aeruginosa (PA) infection in cystic fibrosis (CF) lung disease causes airway neutrophilia and hyperinflammation without effective bacterial clearance. We evaluated the immunostimulatory activities of lipid A, the membrane anchor of LPS, isolated from mutants of PA that synthesize structural variants, present in the airways of patients with CF, to determine if they correlate with disease severity and progression. In a subset of patients with a severe late stage of CF disease, a unique hepta-acylated lipid A, hepta-1855, is synthesized. In primary human cell cultures, we found that hepta-1855 functioned as a potent TLR4 agonist by priming neutrophil respiratory burst and stimulating strong IL-8 from monocytes and neutrophils. hepta-1855 also had a potent survival effect on neutrophils. However, it was less efficient in stimulating neutrophil granule exocytosis and also less potent in triggering proinflammatory TNF-α response from monocytes. In PA isolates that do not synthesize hepta-1855, a distinct CF-specific adaptation favors synthesis of a penta-1447 and hexa-1685 LPS mixture. We found that penta-1447 lacked immunostimulatory activity but interfered with inflammatory IL-8 synthesis in response to hexa-1685. Together, these observations suggest a potential contribution of hepta-1855 to maintenance of the inflammatory burden in late-stage CF by recruiting neutrophils via IL-8 and promoting their survival, an effect presumably amplified by the absence of penta-1447. Moreover, the relative inefficiency of hepta-1855 in triggering neutrophil degranulation may partly explain the persistence of PA in CF disease, despite extensive airway neutrophilia.
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Affiliation(s)
- Shuvasree SenGupta
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, Kentucky, USA
| | - Lauren E Hittle
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, Maryland, USA
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, Maryland, USA
| | - Silvia M Uriarte
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, Kentucky, USA; .,Department of Medicine, University of Louisville School of Medicine, Louisville, Kentucky, USA; and
| | - Thomas C Mitchell
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, Kentucky, USA;
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Maldonado RF, Sá-Correia I, Valvano MA. Lipopolysaccharide modification in Gram-negative bacteria during chronic infection. FEMS Microbiol Rev 2016; 40:480-93. [PMID: 27075488 PMCID: PMC4931227 DOI: 10.1093/femsre/fuw007] [Citation(s) in RCA: 372] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 08/23/2015] [Accepted: 03/10/2016] [Indexed: 12/16/2022] Open
Abstract
The Gram-negative bacterial lipopolysaccharide (LPS) is a major component of the outer membrane that plays a key role in host-pathogen interactions with the innate immune system. During infection, bacteria are exposed to a host environment that is typically dominated by inflammatory cells and soluble factors, including antibiotics, which provide cues about regulation of gene expression. Bacterial adaptive changes including modulation of LPS synthesis and structure are a conserved theme in infections, irrespective of the type or bacteria or the site of infection. In general, these changes result in immune system evasion, persisting inflammation and increased antimicrobial resistance. Here, we review the modifications of LPS structure and biosynthetic pathways that occur upon adaptation of model opportunistic pathogens (Pseudomonas aeruginosa, Burkholderia cepacia complex bacteria, Helicobacter pylori and Salmonella enterica) to chronic infection in respiratory and gastrointestinal sites. We also discuss the molecular mechanisms of these variations and their role in the host-pathogen interaction.
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Affiliation(s)
- Rita F. Maldonado
- Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon 1049-001, Portugal
| | - Isabel Sá-Correia
- Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon 1049-001, Portugal
| | - Miguel A. Valvano
- Department of Microbiology and Immunology, University of Western Ontario, London, ON N6A 5C1, Canada
- Centre for Infection and Immunity, Queen's University Belfast, Belfast BT9 7BL, UK
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Within-Host Evolution of the Dutch High-Prevalent Pseudomonas aeruginosa Clone ST406 during Chronic Colonization of a Patient with Cystic Fibrosis. PLoS One 2016; 11:e0158106. [PMID: 27337151 PMCID: PMC4918941 DOI: 10.1371/journal.pone.0158106] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 06/12/2016] [Indexed: 01/01/2023] Open
Abstract
This study investigates adaptation of ST406, a prevalent P. aeruginosa clone, present in 15% of chronically infected cystic fibrosis (CF) patients in the Netherlands, in a newly infected CF patient during three years using whole genome sequencing (WGS), transcriptomics, and phenotypic assays, including biofilm formation. WGS-based phylogeny demonstrates that ST406 is genetically distinct from other reported CF related strains or epidemic clones. Comparative genomic analysis of the early (S1) and late (S2) isolate yielded 42 single nucleotide polymorphisms (SNPs) and 10 indels and a single 7 kb genomic fragment only found in S2. Most SNPs and differentially expressed genes encoded proteins involved in metabolism, secretion and signal transduction or transcription. SNPs were identified in regulator genes mexT and exsA and coincided with differential gene expression of mexE and mexF, encoding the MexE/F efflux pump, genes encoding the type six secretion system (T6SS) and type three secretion system (T3SS), which have also been previously implicated in adaptation of other P. aeruginosa strains during chronic infection of CF lungs. The observation that genetically different strains from different patients have accumulated similar genetic adaptations supports the concept of adaptive parallel evolution of P. aeruginosa in chronically infected CF patients. Phenotypically, there was loss of biofilm maturation coinciding with a significant lower level of transcription of both bfmR and bfmS during chronic colonization. These data suggest that the high-prevalent Dutch CF clone ST406 displays adaptation to the CF lung niche, which involves a limited number of mutations affecting regulators controlling biofilm formation and secretion and genes involved in metabolism. These genes could provide good targets for anti-pseudomonal therapy.
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Hathroubi S, Beaudry F, Provost C, Martelet L, Segura M, Gagnon CA, Jacques M. Impact of Actinobacillus pleuropneumoniae biofilm mode of growth on the lipid A structures and stimulation of immune cells. Innate Immun 2016; 22:353-62. [PMID: 27226465 DOI: 10.1177/1753425916649676] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 04/21/2016] [Indexed: 11/17/2022] Open
Abstract
Actinobacillus pleuropneumoniae (APP), the etiologic agent of porcine pleuropneumonia, forms biofilms on biotic and abiotic surfaces. APP biofilms confers resistance to antibiotics. To our knowledge, no studies have examined the role of APP biofilm in immune evasion and infection persistence. This study was undertaken to (i) investigate biofilm-associated LPS modifications occurring during the switch to biofilm mode of growth; and (ii) characterize pro-inflammatory cytokines expression in porcine pulmonary alveolar macrophages (PAMs) and proliferation in porcine PBMCs challenged with planktonic or biofilm APP cells. Extracted lipid A samples from biofilm and planktonic cultures were analyzed by HPLC high-resolution, accurate mass spectrometry. Biofilm cells displayed significant changes in lipid A profiles when compared with their planktonic counterparts. Furthermore, in vitro experiments were conducted to examine the inflammatory response of PAMs exposed to UV-inactivated APP grown in biofilm or in suspension. Relative mRNA expression of pro-inflammatory genes IL1, IL6, IL8 and MCP1 decreased in PAMs when exposed to biofilm cells compared to planktonic cells. Additionally, the biofilm state reduced PBMCs proliferation. Taken together, APP biofilm cells show a weaker ability to stimulate innate immune cells, which could be due, in part, to lipid A structure modifications.
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Affiliation(s)
- Skander Hathroubi
- Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada
| | - Francis Beaudry
- Groupe de Recherche en Pharmacologie Animale du Québec, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - Chantale Provost
- Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada
| | - Léa Martelet
- Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada
| | - Mariela Segura
- Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada
| | - Carl A Gagnon
- Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada
| | - Mario Jacques
- Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada
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45
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Bruscia EM, Zhang PX, Barone C, Scholte BJ, Homer R, Krause DS, Egan ME. Increased susceptibility of Cftr-/- mice to LPS-induced lung remodeling. Am J Physiol Lung Cell Mol Physiol 2016; 310:L711-9. [PMID: 26851259 DOI: 10.1152/ajplung.00284.2015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 01/29/2016] [Indexed: 01/05/2023] Open
Abstract
Cystic fibrosis (CF) is caused by homozygous mutations of the CF transmembrane conductance regulator (CFTR) Cl(-) channel, which result in chronic pulmonary infection and inflammation, the major cause of morbidity and mortality. Although these processes are clearly related to each other, each is likely to contribute to the pathology differently. Understanding the contribution of each of these processes to the overall pathology has been difficult, because they are usually so intimately connected. Various CF mouse models have demonstrated abnormal immune responses compared with wild-type (WT) littermates when challenged with live bacteria or bacterial products acutely. However, these studies have not investigated the consequences of persistent inflammation on lung tissue in CF mice, which may better model the lung pathology in patients. We characterized the lung pathology and immune response of Cftr(-/-) (CF) and Cftr(+/+) (WT) mice to chronic administration of Pseudomonas aeruginosa lipopolysaccharide (LPS). We show that, after long-term repeated LPS exposure, CF mice develop an abnormal and persistent immune response, which is associated with more robust structural changes in the lung than those observed in WT mice. Although CF mice and their WT littermates develop lung pathology after chronic exposure to LPS, the inflammation and damage resolve in WT mice. However, CF mice do not recover efficiently, and, as a consequence of their chronic inflammation, CF mice are more susceptible to morphological changes and lung remodeling. This study shows that chronic inflammation alone contributes significantly to aspects of CF lung pathology.
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Affiliation(s)
- Emanuela M Bruscia
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut
| | - Ping-Xia Zhang
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Christina Barone
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut
| | - Bob J Scholte
- Department of Cell Biology, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Robert Homer
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut
| | - Diane S Krause
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut; Department of Pathology, Yale University School of Medicine, New Haven, Connecticut
| | - Marie E Egan
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut; and
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46
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Larrouy-Maumus G, Clements A, Filloux A, McCarthy RR, Mostowy S. Direct detection of lipid A on intact Gram-negative bacteria by MALDI-TOF mass spectrometry. J Microbiol Methods 2016; 120:68-71. [PMID: 26656001 PMCID: PMC4717120 DOI: 10.1016/j.mimet.2015.12.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 12/02/2015] [Accepted: 12/02/2015] [Indexed: 11/29/2022]
Abstract
The purification and characterization of Gram-negative bacterial lipid A is tedious and time-consuming. Herein we report a rapid and sensitive method to identify lipid A directly on intact bacteria without any chemical treatment or purification, using an atypical solvent system to solubilize the matrix combined with MALDI-TOF mass spectrometry.
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Affiliation(s)
- Gerald Larrouy-Maumus
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK.
| | - Abigail Clements
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK
| | - Alain Filloux
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK
| | - Ronan R McCarthy
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK
| | - Serge Mostowy
- MRC Centre for Molecular Bacteriology and Infection, Department of Medicine, Imperial College London, London, UK
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47
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Basheer SM, Bouchez V, Novikov A, Augusto LA, Guiso N, Caroff M. Structure activity characterization of Bordetella petrii lipid A, from environment to human isolates. Biochimie 2016; 120:87-95. [DOI: 10.1016/j.biochi.2015.07.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 07/06/2015] [Indexed: 11/30/2022]
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48
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Couto N, Schooling SR, Dutcher JR, Barber J. Proteome Profiles of Outer Membrane Vesicles and Extracellular Matrix of Pseudomonas aeruginosa Biofilms. J Proteome Res 2015; 14:4207-22. [PMID: 26303878 DOI: 10.1021/acs.jproteome.5b00312] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In the present work, two different proteomic platforms, gel-based and gel-free, were used to map the matrix and outer membrane vesicle exoproteomes of Pseudomonas aeruginosa PAO1 biofilms. These two proteomic strategies allowed us a confident identification of 207 and 327 proteins from enriched outer membrane vesicles and whole matrix isolated from biofilms. Because of the physicochemical characteristics of these subproteomes, the two strategies showed complementarity, and thus, the most comprehensive analysis of P. aeruginosa exoproteome to date was achieved. Under our conditions, outer membrane vesicles contribute approximately 20% of the whole matrix proteome, demonstrating that membrane vesicles are an important component of the matrix. The proteomic profiles were analyzed in terms of their biological context, namely, a biofilm. Accordingly relevant metabolic processes involved in cellular adaptation to the biofilm lifestyle as well as those related to P. aeruginosa virulence capabilities were a key feature of the analyses. The diversity of the matrix proteome corroborates the idea of high heterogeneity within the biofilm; cells can display different levels of metabolism and can adapt to local microenvironments making this proteomic analysis challenging. In addition to analyzing our own primary data, we extend the analysis to published data by other groups in order to deepen our understanding of the complexity inherent within biofilm populations.
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Affiliation(s)
- Narciso Couto
- Michael Barber Centre for Mass Spectrometry, Manchester Institute for Biotechnology, University of Manchester , Princess Road, Manchester, M1 7DN, U.K
| | - Sarah R Schooling
- Department of Molecular and Cellular Biology, College of Biological Science, University of Guelph , Guelph, ON N1G 2W1, Canada.,Department of Physics, University of Guelph , Guelph, ON N1G 2W1, Canada
| | - John R Dutcher
- Department of Physics, University of Guelph , Guelph, ON N1G 2W1, Canada
| | - Jill Barber
- Michael Barber Centre for Mass Spectrometry, Manchester Institute for Biotechnology, University of Manchester , Princess Road, Manchester, M1 7DN, U.K.,Manchester Pharmacy School, University of Manchester , Stopford Building, Oxford Road, Manchester, M13 9PT, U.K
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Hittle LE, Powell DA, Jones JW, Tofigh M, Goodlett DR, Moskowitz SM, Ernst RK. Site-specific activity of the acyltransferases HtrB1 and HtrB2 in Pseudomonas aeruginosa lipid A biosynthesis. Pathog Dis 2015. [PMID: 26223882 DOI: 10.1093/femspd/ftv053] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Pseudomonas aeruginosa (PA) is an opportunistic Gram-negative pathogen associated with nosocomial infections, acute infections and chronic lung infections in patients with cystic fibrosis. The ability of PA to cause infection can be attributed to its ability to adapt to a multitude of environments. Modification of the lipid A portion of lipopolysaccharide (LPS) is a vital mechanism Gram-negative pathogens use to remodel the outer membrane in response to environmental stimuli. Lipid A, the endotoxic moiety of LPS, is the major component of the outer leaflet of the outer membrane of Gram-negative bacteria making it a critical factor for bacterial adaptation. One way PA modifies its lipid A is through the addition of laurate and 2-hydroxylaurate. This secondary or late acylation is carried out by the acyltransferase, HtrB (LpxL). Analysis of the PA genome revealed the presence of two htrB homologs, PA0011 (htrB1) and PA3242 (htrB2). In this study, we were able to show that each gene identified is responsible for site-specific modification of lipid A. Additionally, deletions of either gene altered resistance to specific classes of antibiotics, cationic antimicrobial peptides and increased membrane permeability suggesting a role for these enzymes in maintaining optimal membrane organization and integrity.
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Affiliation(s)
- Lauren E Hittle
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Daniel A Powell
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Jace W Jones
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195, USA
| | - Majid Tofigh
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - David R Goodlett
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195, USA
| | - Samuel M Moskowitz
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195, USA Department of Pediatrics, Massachusetts General Hospital, Boston, MA 20114, USA
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
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Nowicki EM, O'Brien JP, Brodbelt JS, Trent MS. Extracellular zinc induces phosphoethanolamine addition to Pseudomonas aeruginosa lipid A via the ColRS two-component system. Mol Microbiol 2015; 97:166-78. [PMID: 25846400 DOI: 10.1111/mmi.13018] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/01/2015] [Indexed: 01/01/2023]
Abstract
Gram-negative bacteria survive harmful environmental stressors by modifying their outer membrane. Much of this protection is afforded upon remodeling of the lipid A region of the major surface molecule lipopolysaccharide (LPS). For example, the addition of cationic substituents, such as 4-amino-4-deoxy-L-arabinose (L-Ara4N) and phosphoehthanolamine (pEtN) at the lipid A phosphate groups, is often induced in response to specific environmental flux stabilizing the outer membrane. The work herein represents the first report of pEtN addition to Pseudomonas aeruginosa lipid A. We have identified the key pEtN transferase which we named EptAPa and characterized its strict activity on only one position of lipid A, contrasting from previously studied EptA enzymes. We further show that transcription of eptAP a is regulated by zinc via the ColRS two-component system instead of the PmrAB system responsible for eptA regulation in E. coli and Salmonella enterica. Further, although L-Ara4N is readily added to the same position of lipid A as pEtN under certain environmental conditions, ColR specifically induces pEtN addition to lipid A in lieu of L-Ara4N when Zn2+ is present. The unique, specific regulation of eptAP a transcription and enzymatic activity described in this work demonstrates the tight yet inducible control over LPS modification in P. aeruginosa.
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Affiliation(s)
- Emily M Nowicki
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX, USA
| | - John P O'Brien
- Department of Chemistry, University of Texas at Austin, Austin, TX, USA
| | | | - M Stephen Trent
- Department of Infectious Diseases, University of Georgia, College of Veterinary Medicine, Athens, GA, USA
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