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Nhu NTK, Phan MD, Hancock SJ, Peters KM, Alvarez-Fraga L, Forde BM, Andersen SB, Miliya T, Harris PNA, Beatson SA, Schlebusch S, Bergh H, Turner P, Brauner A, Westerlund-Wikström B, Irwin AD, Schembri MA. High-risk Escherichia coli clones that cause neonatal meningitis and association with recrudescent infection. eLife 2024; 12:RP91853. [PMID: 38622998 PMCID: PMC11021048 DOI: 10.7554/elife.91853] [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: 04/17/2024] Open
Abstract
Neonatal meningitis is a devastating disease associated with high mortality and neurological sequelae. Escherichia coli is the second most common cause of neonatal meningitis in full-term infants (herein NMEC) and the most common cause of meningitis in preterm neonates. Here, we investigated the genomic relatedness of a collection of 58 NMEC isolates spanning 1974-2020 and isolated from seven different geographic regions. We show NMEC are comprised of diverse sequence types (STs), with ST95 (34.5%) and ST1193 (15.5%) the most common. No single virulence gene profile was conserved in all isolates; however, genes encoding fimbrial adhesins, iron acquisition systems, the K1 capsule, and O antigen types O18, O75, and O2 were most prevalent. Antibiotic resistance genes occurred infrequently in our collection. We also monitored the infection dynamics in three patients that suffered recrudescent invasive infection caused by the original infecting isolate despite appropriate antibiotic treatment based on antibiogram profile and resistance genotype. These patients exhibited severe gut dysbiosis. In one patient, the causative NMEC isolate was also detected in the fecal flora at the time of the second infection episode and after treatment. Thus, although antibiotics are the standard of care for NMEC treatment, our data suggest that failure to eliminate the causative NMEC that resides intestinally can lead to the existence of a refractory reservoir that may seed recrudescent infection.
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Affiliation(s)
- Nguyen Thi Khanh Nhu
- Institute for Molecular Bioscience (IMB), The University of QueenslandBrisbaneAustralia
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbaneAustralia
- Australian Infectious Diseases Research Centre, The University of QueenslandBrisbaneAustralia
| | - Minh-Duy Phan
- Institute for Molecular Bioscience (IMB), The University of QueenslandBrisbaneAustralia
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbaneAustralia
- Australian Infectious Diseases Research Centre, The University of QueenslandBrisbaneAustralia
| | - Steven J Hancock
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbaneAustralia
- Australian Infectious Diseases Research Centre, The University of QueenslandBrisbaneAustralia
| | - Kate M Peters
- Institute for Molecular Bioscience (IMB), The University of QueenslandBrisbaneAustralia
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbaneAustralia
- Australian Infectious Diseases Research Centre, The University of QueenslandBrisbaneAustralia
| | - Laura Alvarez-Fraga
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbaneAustralia
- Australian Infectious Diseases Research Centre, The University of QueenslandBrisbaneAustralia
| | - Brian M Forde
- Australian Infectious Diseases Research Centre, The University of QueenslandBrisbaneAustralia
- University of Queensland Centre for Clinical Research, The University of QueenslandBrisbaneAustralia
| | - Stacey B Andersen
- Genome Innovation Hub, The University of QueenslandBrisbaneAustralia
| | - Thyl Miliya
- Cambodia Oxford Medical Research Unit, Angkor Hospital for ChildrenSiem ReapCambodia
| | - Patrick NA Harris
- University of Queensland Centre for Clinical Research, The University of QueenslandBrisbaneAustralia
- Pathology Queensland, Queensland HealthBrisbaneAustralia
| | - Scott A Beatson
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbaneAustralia
- Australian Infectious Diseases Research Centre, The University of QueenslandBrisbaneAustralia
| | - Sanmarie Schlebusch
- University of Queensland Centre for Clinical Research, The University of QueenslandBrisbaneAustralia
- Pathology Queensland, Queensland HealthBrisbaneAustralia
- Q-PHIRE Genomics and Public Health Microbiology, Forensic and Scientific Services, Coopers PlainsBrisbaneAustralia
| | - Haakon Bergh
- Pathology Queensland, Queensland HealthBrisbaneAustralia
| | - Paul Turner
- Cambodia Oxford Medical Research Unit, Angkor Hospital for ChildrenSiem ReapCambodia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
| | - Annelie Brauner
- Department of Microbiology, Tumor and Cell Biology, Division of Clinical Microbiology, Karolinska Institutet and Karolinska University HospitalStockholmSweden
| | | | - Adam D Irwin
- Australian Infectious Diseases Research Centre, The University of QueenslandBrisbaneAustralia
- University of Queensland Centre for Clinical Research, The University of QueenslandBrisbaneAustralia
- Infection Management Prevention Service, Queensland Children's HospitalBrisbaneAustralia
| | - Mark A Schembri
- Institute for Molecular Bioscience (IMB), The University of QueenslandBrisbaneAustralia
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbaneAustralia
- Australian Infectious Diseases Research Centre, The University of QueenslandBrisbaneAustralia
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Hassan IZ, Qekwana DN, Naidoo V. Do Pathogenic Escherichia coli Isolated from Gallus gallus in South Africa Carry Co-Resistance Toward Colistin and Carbapenem Antimicrobials? Foodborne Pathog Dis 2023; 20:388-397. [PMID: 37471208 DOI: 10.1089/fpd.2023.0047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/22/2023] Open
Abstract
Colistin and carbapenems are critically important antimicrobials often used as a last resort to manage multidrug-resistant bacterial infections in humans. With limited alternatives, resistance to these antimicrobials is of concern as organisms could potentially spread horizontally rendering treatments ineffective. The aim of this study was to investigate co-resistance to colistin and carbapenems among Escherichia coli isolated from poultry in South Africa. Forty-six E. coli strains obtained from clinical cases of breeder and broiler chickens were used. In addition to other antibiotics, all the isolates were tested against colistin and carbapenems using broth microdilution. Multiplex polymerase chain reactions were used to investigate the presence of colistin (mcr-1 to 5) and carbapenem (blaOXA-48, blaNDM-1, and blaVIM) resistance genes. Isolates exhibiting colistin resistance (>2 μg/mL) underwent a whole-genome sequencing analysis. Resistance to colistin (10.9%) and cefepime (6.5%) was noted with all colistin-resistant strains harboring the mcr-1 gene. None of the E. coli isolates were resistant to carbapenems nor carried the other resistant genes (mcr-2 to 5, blaOXA-48, blaNDM-1, and blaVIM). The mcr-1-positive strains belonged to sequence types ST117 and ST156 and carried virulence genes ompA, aslA, fdeC, fimH, iroN, iutA, tsh, pic, ast A and set 1A/1B. In conclusion, clinical E. coli strains from chickens in this study possessed mobile resistance genes for colistin and several other clinically relevant antimicrobials but not carbapenems. Additionally, they belonged to sequence types in addition to carrying virulence factors often associated with human extraintestinal pathogenic E. coli infections. Thus, the potential risk of transmitting these strains to humans cannot be underestimated especially if sick birds are dispatched into the thriving poorly regulated Cornish hen industry. The need for routine veterinary surveillance and monitoring of antimicrobial resistance, antimicrobial use and the importance of strengthening regulations guiding the informal poultry sector remains important.
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Affiliation(s)
- Ibrahim Zubairu Hassan
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - Daniel N Qekwana
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - Vinny Naidoo
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
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Zhurilov PA, Andriyanov PA, Tutrina AI, Razheva IV, Liskova EA, Gladkova NA, Kashina DD, Yashin IV, Blokhin AA. Characterization and comparative analysis of the Escherichia marmotae M-12 isolate from bank vole (Myodes glareolus). Sci Rep 2023; 13:13949. [PMID: 37626115 PMCID: PMC10457355 DOI: 10.1038/s41598-023-41223-0] [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: 05/19/2023] [Accepted: 08/23/2023] [Indexed: 08/27/2023] Open
Abstract
The Escherichia marmotae is a bacterium of the Enterobacterales order, which was first isolated from the Himalayan marmot (Marmota himalayana). Recently E. marmotae has been shown to cause severe infections in humans. Wild animals were suggested to be a natural reservoir of this bacterium. The present study describes the first case of E. marmotae isolation from an apparently healthy wild bank vole (Myodes glareolus). Phenotype, as well as genotype-based techniques, were applied to characterize E. marmotae M-12 isolate. E. marmotae M-12 had the capsule-positive phenotype, high adhesion to human erythrocytes and HEp-2 cells as well as a low invasion into HEp-2 cells. E. marmotae M-12 was avirulent in mice. The phylogenomic analyses of E. marmotae showed dispersed phylogenetic structure among isolates of different origins. Virulome analysis of M-12 isolate revealed the presence of the following factors: siderophores, heme uptake systems, capsule synthesis, curli and type I fimbriae, flagella proteins, OmpA porin, etc. Comparative virulome analysis among available E. marmotae genomes revealed the presence of capsule K1 genes mostly in pathogenic isolates and OmpA porin presence among all strains. We assume that the K1 capsule and OmpA porin play a key role in the virulence of E. marmotae. Pathogenesis of the latter might be similar to extraintestinal pathogenic E. coli.
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Affiliation(s)
- Pavel A Zhurilov
- Federal Research Center for Virology and Microbiology, Branch in Nizhny Novgorod, 603950, Nizhny Novgorod, Russia.
| | - Pavel A Andriyanov
- Federal Research Center for Virology and Microbiology, Branch in Nizhny Novgorod, 603950, Nizhny Novgorod, Russia
| | - Anastasia I Tutrina
- Federal Research Center for Virology and Microbiology, Branch in Nizhny Novgorod, 603950, Nizhny Novgorod, Russia
| | - Irina V Razheva
- Federal Research Center for Virology and Microbiology, Branch in Nizhny Novgorod, 603950, Nizhny Novgorod, Russia
| | - Elena A Liskova
- Federal Research Center for Virology and Microbiology, Branch in Nizhny Novgorod, 603950, Nizhny Novgorod, Russia
| | - Nadezda A Gladkova
- Federal Research Center for Virology and Microbiology, Branch in Nizhny Novgorod, 603950, Nizhny Novgorod, Russia
| | - Daria D Kashina
- Federal Research Center for Virology and Microbiology, Branch in Nizhny Novgorod, 603950, Nizhny Novgorod, Russia
| | - Ivan V Yashin
- Federal Research Center for Virology and Microbiology, Branch in Nizhny Novgorod, 603950, Nizhny Novgorod, Russia
| | - Andrey A Blokhin
- Federal Research Center for Virology and Microbiology, Branch in Nizhny Novgorod, 603950, Nizhny Novgorod, Russia
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Thapa HB, Kohl P, Zingl FG, Fleischhacker D, Wolinski H, Kufer TA, Schild S. Characterization of the Inflammatory Response Evoked by Bacterial Membrane Vesicles in Intestinal Cells Reveals an RIPK2-Dependent Activation by Enterotoxigenic Escherichia coli Vesicles. Microbiol Spectr 2023; 11:e0111523. [PMID: 37306596 PMCID: PMC10433812 DOI: 10.1128/spectrum.01115-23] [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: 03/15/2023] [Accepted: 05/23/2023] [Indexed: 06/13/2023] Open
Abstract
Although the immunomodulatory potency of bacterial membrane vesicles (MVs) is widely acknowledged, their interactions with host cells and the underlying signaling pathways have not been well studied. Herein, we provide a comparative analysis of the proinflammatory cytokine profile secreted by human intestinal epithelial cells exposed to MVs derived from 32 gut bacteria. In general, outer membrane vesicles (OMVs) from Gram-negative bacteria induced a stronger proinflammatory response than MVs from Gram-positive bacteria. However, the quality and quantity of cytokine induction varied between MVs from different species, highlighting their unique immunomodulatory properties. OMVs from enterotoxigenic Escherichia coli (ETEC) were among those showing the strongest proinflammatory potency. In depth analyses revealed that the immunomodulatory activity of ETEC OMVs relies on a so far unprecedented two-step mechanism, including their internalization into host cells followed by intracellular recognition. First, OMVs are efficiently taken up by intestinal epithelial cells, which mainly depends on caveolin-mediated endocytosis as well as the presence of the outer membrane porins OmpA and OmpF on the MVs. Second, lipopolysaccharide (LPS) delivered by OMVs is intracellularly recognized by novel caspase- and RIPK2-dependent pathways. This recognition likely occurs via detection of the lipid A moiety as ETEC OMVs with underacylated LPS exhibited reduced proinflammatory potency but similar uptake dynamics compared to OMVs derived from wild-type (WT) ETEC. Intracellular recognition of ETEC OMVs in intestinal epithelial cells is pivotal for the proinflammatory response as inhibition of OMV uptake also abolished cytokine induction. The study signifies the importance of OMV internalization by host cells to exercise their immunomodulatory activities. IMPORTANCE The release of membrane vesicles from the bacterial cell surface is highly conserved among most bacterial species, including outer membrane vesicles (OMVs) from Gram-negative bacteria as well as vesicles liberated from the cytoplasmic membrane of Gram-positive bacteria. It is becoming increasingly evident that these multifactorial spheres, carrying membranous, periplasmic, and even cytosolic content, contribute to intra- and interspecies communication. In particular, gut microbiota and the host engage in a myriad of immunogenic and metabolic interactions. This study highlights the individual immunomodulatory activities of bacterial membrane vesicles from different enteric species and provides new mechanistic insights into the recognition of ETEC OMVs by human intestinal epithelial cells.
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Affiliation(s)
- Himadri B. Thapa
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Paul Kohl
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Franz G. Zingl
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | | | - Heimo Wolinski
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- Field of Excellence Biohealth, University of Graz, Graz, Austria
| | - Thomas A. Kufer
- Department of Immunology, Institute of Nutritional Medicine, University of Hohenheim, Stuttgart, Germany
| | - Stefan Schild
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- Field of Excellence Biohealth, University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
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Farid N, Waheed A, Motwani S. Synthetic and natural antimicrobials as a control against food borne pathogens: A review. Heliyon 2023; 9:e17021. [PMID: 37484319 PMCID: PMC10361103 DOI: 10.1016/j.heliyon.2023.e17021] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 05/28/2023] [Accepted: 06/04/2023] [Indexed: 07/25/2023] Open
Abstract
Food borne pathogens are one of the most common yet concerning cause of illnesses around the globe. These microbes invade the body via food items, through numerous mediums of contamination and it is impossible to completely eradicate these organisms from food. Extensive research has been made regarding their treatment. Unfortunately, the only available treatment currently is by antibiotics. Recent exponential increase in antibiotic resistance and the side effect of synthetic compounds have established a need for alternate therapies that could be utilized either on their own or along with antibiotics to provide protection against food-borne diseases. The aim of this review is to provide information regarding some common food borne diseases, their current and possible natural treatment. It will include details regarding some common foodborne pathogens, the disease they cause, prevalence, manifestations and treatment of the respective disease. Some natural modes of potential treatment will be summarized, which including phytochemicals, derived from plants either as crude extracts or as purified form and Bacteriocins as microbial based treatment, obtained from various types of bacteria. The paper will describe their mechanism of action, classification, susceptible organisms, some antimicrobial compounds and producing organisms, application in food systems and as potential treatment. Along with that, synthetic treatment i.e., antibiotics will be discussed including the first-line treatment of some common food borne infections, prevalence and mechanism of resistance against antibiotics in the pathogens.
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Affiliation(s)
- Neha Farid
- Corresponding author. Shaheed Zulfikar Ali Bhutto Institute of Science and Technology, Pakistan.
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OmpA is involved in the invasion of duck brain microvascular endothelial cells by Riemerella anatipestifer. Vet Microbiol 2023; 280:109692. [PMID: 36863175 DOI: 10.1016/j.vetmic.2023.109692] [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: 04/24/2022] [Revised: 11/25/2022] [Accepted: 02/15/2023] [Indexed: 02/18/2023]
Abstract
Bacterial meningitis is a major cause of morbidity and mortality. Despite advances in antimicrobial chemotherapy, the disease remains detrimental to humans, livestock, and poultry. Riemerella anatipestifer is a gram-negative bacterium causing duckling serositis and meningitis. However, the virulence factors contributing to its binding and invasion of duck brain microvascular endothelial cells (DBMECs) and penetration of the blood-brain barrier (BBB) have never been reported. In this study, immortalized DBMECs were successfully generated and used as an in vitro-model of duck BBB. Furthermore, ompA gene deletion mutant of the pathogen and multiple complemented strains carrying the complete ompA gene and its truncated forms were constructed. Bacterial growth, invasion, and adhesion assays and animal experiments were performed. The results show that the OmpA protein of R. anatipestifer had no effect on bacterial growth and adhesion ability to DBMECs. The role of OmpA in the invasion of R. anatipestifer into DBMECs and duckling BBB was confirmed. The amino acids 230-242 of OmpA represents a key domain involved in R. anatipestifer invasion. In addition, another OmpA1164 protein constituted by the amino acids 102-488 within OmpA could function as a complete OmpA. The signal peptide sequence from amino acids 1-21 had no significant effect on OmpA functions. In conclusion, this study illustrated that OmpA is an important virulence factor mediating R. anatipestifer invasion of DBMECs and penetration of the duckling BBB.
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Pokharel P, Dhakal S, Dozois CM. The Diversity of Escherichia coli Pathotypes and Vaccination Strategies against This Versatile Bacterial Pathogen. Microorganisms 2023; 11:344. [PMID: 36838308 PMCID: PMC9965155 DOI: 10.3390/microorganisms11020344] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 01/24/2023] [Accepted: 01/25/2023] [Indexed: 02/03/2023] Open
Abstract
Escherichia coli (E. coli) is a gram-negative bacillus and resident of the normal intestinal microbiota. However, some E. coli strains can cause diseases in humans, other mammals and birds ranging from intestinal infections, for example, diarrhea and dysentery, to extraintestinal infections, such as urinary tract infections, respiratory tract infections, meningitis, and sepsis. In terms of morbidity and mortality, pathogenic E. coli has a great impact on public health, with an economic cost of several billion dollars annually worldwide. Antibiotics are not usually used as first-line treatment for diarrheal illness caused by E. coli and in the case of bloody diarrhea, antibiotics are avoided due to the increased risk of hemolytic uremic syndrome. On the other hand, extraintestinal infections are treated with various antibiotics depending on the site of infection and susceptibility testing. Several alarming papers concerning the rising antibiotic resistance rates in E. coli strains have been published. The silent pandemic of multidrug-resistant bacteria including pathogenic E. coli that have become more difficult to treat favored prophylactic approaches such as E. coli vaccines. This review provides an overview of the pathogenesis of different pathotypes of E. coli, the virulence factors involved and updates on the major aspects of vaccine development against different E. coli pathotypes.
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Affiliation(s)
- Pravil Pokharel
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), 531 Boul des Prairies, Laval, QC H7V 1B7, Canada
- Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Faculté de Médecine Vétérinaire, Université de Montréal Saint-Hyacinthe, Saint-Hyacinthe, QC J2S 2M2, Canada
| | - Sabin Dhakal
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), 531 Boul des Prairies, Laval, QC H7V 1B7, Canada
- Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Faculté de Médecine Vétérinaire, Université de Montréal Saint-Hyacinthe, Saint-Hyacinthe, QC J2S 2M2, Canada
| | - Charles M. Dozois
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), 531 Boul des Prairies, Laval, QC H7V 1B7, Canada
- Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Faculté de Médecine Vétérinaire, Université de Montréal Saint-Hyacinthe, Saint-Hyacinthe, QC J2S 2M2, Canada
- Pasteur Network, Laval, QC H7V 1B7, Canada
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Alexpandi R, Abirami G, Murugesan B, Durgadevi R, Swasthikka RP, Cai Y, Ragupathi T, Ravi AV. Tocopherol-assisted magnetic Ag-Fe 3O 4-TiO 2 nanocomposite for photocatalytic bacterial-inactivation with elucidation of mechanism and its hazardous level assessment with zebrafish model. JOURNAL OF HAZARDOUS MATERIALS 2023; 442:130044. [PMID: 36179621 DOI: 10.1016/j.jhazmat.2022.130044] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 09/18/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
In recent years, many endeavours have been prompted with photocatalytic nanomaterials by the need to eradicate pathogenic microorganisms from water bodies. Herein, a tocopherol-assisted Ag-Fe3O4-TiO2 nanocomposite (TAFTN) was synthesized for photocatalytic bacterial inactivation. The prepared TAFTN became active under sunlight due to its narrowed bandgap, inactivating the bacterial contaminants via photo-induced ROS stress. The ROS radicals destroy bacteria by creating oxidative stress, which damages the cell membrane and cellular components such as nucleic acids and proteins. For the first time, the nano-LC-MS/MS-based quantitative proteomics reveals that the disrupted proteins are involved in a variety of cellular functions; the most of these are involved in the metabolic pathway, eventually leading to bacterial death during TAFTN-photocatalysis under sunlight. Furthermore, the toxicity analysis confirmed that the inactivated bacteria seemed to have no detrimental impact on zebrafish model, showing that the disinfected water via TAFTN-photocatalysis is enormously safe. Furthermore, the TAFTN-photocatalysis successfully killed the bacterial cells in natural seawater, indicating the consistent photocatalytic efficacy when recycled repeatedly. The results of this work demonstrate that the produced nanocomposite might be a powerful recyclable and sunlight-active photocatalyst for environmental water treatment.
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Affiliation(s)
- Rajaiah Alexpandi
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Gurusamy Abirami
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Balaji Murugesan
- The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, National Engineering Lab for Textile Fiber Materials and Processing Technology, School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, PR China; Department of Mechanical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea
| | - Ravindran Durgadevi
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Roshni Prithiviraj Swasthikka
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Yurong Cai
- The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, National Engineering Lab for Textile Fiber Materials and Processing Technology, School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Thennarasu Ragupathi
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India
| | - Arumugam Veera Ravi
- Lab in Microbiology and Marine Biotechnology, Department of Biotechnology, School of Biological Sciences, Alagappa University, Karaikudi 630 003, India.
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Liao C, Santoscoy MC, Craft J, Anderson C, Soupir ML, Jarboe LR. Allelic variation of Escherichia coli outer membrane protein A: Impact on cell surface properties, stress tolerance and allele distribution. PLoS One 2022; 17:e0276046. [PMID: 36227900 PMCID: PMC9560509 DOI: 10.1371/journal.pone.0276046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 09/27/2022] [Indexed: 12/02/2022] Open
Abstract
Outer membrane protein A (OmpA) is one of the most abundant outer membrane proteins of Gram-negative bacteria and is known to have patterns of sequence variations at certain amino acids-allelic variation-in Escherichia coli. Here we subjected seven exemplar OmpA alleles expressed in a K-12 (MG1655) ΔompA background to further characterization. These alleles were observed to significantly impact cell surface charge (zeta potential), cell surface hydrophobicity, biofilm formation, sensitivity to killing by neutrophil elastase, and specific growth rate at 42°C and in the presence of acetate, demonstrating that OmpA is an attractive target for engineering cell surface properties and industrial phenotypes. It was also observed that cell surface charge and biofilm formation both significantly correlate with cell surface hydrophobicity, a cell property that is increasingly intriguing for bioproduction. While there was poor alignment between the observed experimental values relative to the known sequence variation, differences in hydrophobicity and biofilm formation did correspond to the identity of residue 203 (N vs T), located within the proposed dimerization domain. The relative abundance of the (I, δ) allele was increased in extraintestinal pathogenic E. coli (ExPEC) isolates relative to environmental isolates, with a corresponding decrease in (I, α) alleles in ExPEC relative to environmental isolates. The (I, α) and (I, δ) alleles differ at positions 203 and 251. Variations in distribution were also observed among ExPEC types and phylotypes. Thus, OmpA allelic variation and its influence on OmpA function warrant further investigation.
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Affiliation(s)
- Chunyu Liao
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, Iowa, United States of America
| | - Miguel C. Santoscoy
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa United States of America
| | - Julia Craft
- Department of Chemical and Biological Engineering, Biological Materials and Processes (BioMAP) NSF REU Program, Iowa State University, Ames, Iowa, United States of America
| | - Chiron Anderson
- Department of Chemical and Biological Engineering, Biological Materials and Processes (BioMAP) NSF REU Program, Iowa State University, Ames, Iowa, United States of America
| | - Michelle L. Soupir
- Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, Iowa, United States of America
| | - Laura R. Jarboe
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, Iowa, United States of America
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa United States of America
- * E-mail:
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Sarkar P, Ghanim M. Interaction of Liberibacter Solanacearum with Host Psyllid Vitellogenin and Its Association with Autophagy. Microbiol Spectr 2022; 10:e0157722. [PMID: 35863005 PMCID: PMC9430699 DOI: 10.1128/spectrum.01577-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 06/14/2022] [Indexed: 12/28/2022] Open
Abstract
Candidatus Liberibacter solanacearum (CLso) haplotype D, transmitted by the carrot psyllid Bactericera trigonica, is a major constraint for carrot production in Israel. Unveiling the molecular interactions between the psyllid vector and CLso can facilitate the development of nonchemical approaches for controlling the disease caused by CLso. Bacterial surface proteins are often known to be involved in adhesion and virulence; however, interactions of CLso with carrot psyllid proteins that have a role in the transmission process has remained unexplored. In this study, we used CLso outer membrane protein (OmpA) and flagellin as baits to screen for psyllid interacting proteins in a yeast two-hybrid system assay. We identified psyllid vitellogenin (Vg) to interact with both OmpA and flagellin of CLso. As Vg and autophagy are often tightly linked, we also studied the expression of autophagy-related genes to further elucidate this interaction. We used the juvenile hormone (JH-III) to induce the expression of Vg, thapsigargin for suppressing autophagy, and rapamycin for inducing autophagy. The results revealed that Vg negatively regulates autophagy. Induced Vg expression significantly suppressed autophagy-related gene expression and the levels of CLso significantly increased, resulting in a significant mortality of the insect. Although the specific role of Vg remains obscure, the findings presented here identify Vg as an important component in the insect immune responses against CLso and may help in understanding the initial molecular response in the vector against Liberibacter. IMPORTANCE Pathogen transmission by vectors involves multiple levels of interactions, and for the transmission of liberibacter species by psyllid vectors, much of these interactions are yet to be explored. Candidatus Liberibacter solanacearum (CLso) haplotype D inflicts severe economic losses to the carrot industry. Understanding the specific interactions at different stages of infection is hence fundamental and could lead to the development of better management strategies to disrupt the transmission of the bacteria to new host plants. Here, we show that two liberibacter membrane proteins interact with psyllid vitellogenin and also induce autophagy. Altering vitellogenin expression directly influences autophagy and CLso abundance in the psyllid vector. Although the exact mechanism underlying this interaction remains unclear, this study highlights the importance of immune responses in the transmission of this disease agent.
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Affiliation(s)
- Poulami Sarkar
- Department of Entomology, Agricultural Research Organization, Volcani Institute, Rishon LeZion, Israel
| | - Murad Ghanim
- Department of Entomology, Agricultural Research Organization, Volcani Institute, Rishon LeZion, Israel
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11
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Cross-Kingdom Infection of Macrophages Reveals Pathogen- and Immune-Specific Global Reprogramming and Adaptation. mBio 2022; 13:e0168722. [PMID: 35862772 PMCID: PMC9426421 DOI: 10.1128/mbio.01687-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The relationship between the human microbiota and infectious disease outcome is a rapidly expanding area of study. Understanding how the host responds to changes in its symbiotic relationship with microbes provides new insight into how disruption can promote disease.
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12
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YbdO Promotes the Pathogenicity of Escherichia coli K1 by Regulating Capsule Synthesis. Int J Mol Sci 2022; 23:ijms23105543. [PMID: 35628353 PMCID: PMC9141747 DOI: 10.3390/ijms23105543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/12/2022] [Accepted: 05/15/2022] [Indexed: 11/17/2022] Open
Abstract
Escherichia coli K1 is the most popular neonatal meningitis-causing Gram-negative bacterium. As a key virulence determinant, the K1 capsule enhances the survival of E. coli K1 in human brain microvascular endothelial cells (HBMECs) upon crossing the blood–brain barrier; however, the regulatory mechanisms of capsule synthesis during E. coli K1 invasion of HBMECs remain unclear. Here, we identified YbdO as a transcriptional regulator that promotes E. coli K1 invasion of HBMECs by directly activating K1 capsule gene expression to increase K1 capsule synthesis. We found that ybdO deletion significantly reduced HBMEC invasion by E. coli K1 and meningitis occurrence in mice. Additionally, electrophoretic mobility shift assay and chromatin immunoprecipitation–quantitative polymerase chain reaction analysis indicated that YbdO directly activates kpsMT and neuDBACES expression, which encode products involved in K1 capsule transport and synthesis by directly binding to the kpsM promoter. Furthermore, ybdO transcription was directly repressed by histone-like nucleoid structuring protein (H-NS), and we observed that acidic pH similar to that of early and late endosomes relieves this transcriptional repression. These findings demonstrated the regulatory mechanism of YbdO on K1 capsule synthesis, providing further insights into the evolution of E. coli K1 pathogenesis and host–pathogen interaction.
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13
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Roles of the Tol/Pal System in Bacterial Pathogenesis and Its Application to Antibacterial Therapy. Vaccines (Basel) 2022; 10:vaccines10030422. [PMID: 35335056 PMCID: PMC8953051 DOI: 10.3390/vaccines10030422] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/03/2022] [Accepted: 03/08/2022] [Indexed: 01/27/2023] Open
Abstract
The Tol/Pal system (also written as “The Tol-Pal system”) is a set of protein complexes produced by most Gram-negative bacteria. It comprises the inner membrane-associated and the outer membrane-anchored subunits composed of the TolA, TolQ, and TolR proteins and the TolB and Pal proteins, respectively. Although the Tol/Pal system was first defined as bacterial proteins involved in colicin uptake of Escherichia coli, its global roles have been characterized in several studies as mentioned in this article. Pathogenesis of many Gram-negative pathogens is sustained by the Tol/Pal system. It is also essential for cell growth and fitness in some pathogens. Therefore, the Tol/Pal system is proposed as a potential target for antimicrobial chemotherapy. Although the tol/pal mutants are low in virulence, they still have the ability to stimulate the immune system. The Pal protein is highly immunogenic and induces both adaptive and innate immune responses. Therefore, the tol/pal mutant strains and Pal proteins also have potential vaccine properties. For these reasons, the Tol/Pal system represents a promising research target in the development of antibacterial therapeutic strategies for refractory infections caused by multi-drug-resistant (MDR), Gram-negative pathogens. In this paper, we summarize studies on the Tol/Pal system associated with bacterial pathogenesis and vaccine development.
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14
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Merfa MV, Fischer ER, de Souza E Silva M, Francisco CS, Della Coletta-Filho H, de Souza AA. Probing the Application of OmpA-Derived Peptides to Disrupt the Acquisition of ' Candidatus Liberibacter asiaticus' by Diaphorina citri. PHYTOPATHOLOGY 2022; 112:163-172. [PMID: 34818904 DOI: 10.1094/phyto-06-21-0252-fi] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Huanglongbing (HLB) is currently the most devastating disease of citrus worldwide. Both bacteria 'Candidatus Liberibacter asiaticus' (CLas) and 'Candidatus Liberibacter americanus' (CLam) are associated with HLB in Brazil but with a strong prevalence of CLas over CLam. Conventionally, HLB management focuses on controlling the insect vector population (Diaphorina citri; also known as Asian citrus psyllid [ACP]) by spraying insecticides, an approach demonstrated to be mostly ineffective. Thus, development of novel, more efficient HLB control strategies is required. The multifunctional bacterial outer membrane protein OmpA is involved in several molecular processes between bacteria and their hosts and has been suggested as a target for bacterial control. Curiously, OmpA is absent in CLam in comparison with CLas, suggesting a possible role in host interaction. Therefore, in the current study, we have treated ACPs with different OmpA-derived peptides, aiming to evaluate acquisition of CLas by the insect vector. Treatment of psyllids with 5 µM of Pep1, Pep3, Pep5, and Pep6 in artificial diet significantly reduced the acquisition of CLas, whereas increasing the concentration of Pep5 and Pep6 to 50 µM abolished this process. In addition, in planta treatment with 50 µM of Pep6 also significantly decreased the acquisition of CLas, and sweet orange plants stably absorbed and maintained this peptide for as long as 3 months post the final application. Together, our results demonstrate the promising use of OmpA-derived peptides as a novel biotechnological tool to control CLas.
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Affiliation(s)
- Marcus Vinícius Merfa
- Centro de Citricultura Sylvio Moreira, Instituto Agronômico-IAC, Cordeirópolis, SP 13490-970, Brazil
| | - Eduarda Regina Fischer
- Centro de Citricultura Sylvio Moreira, Instituto Agronômico-IAC, Cordeirópolis, SP 13490-970, Brazil
| | - Mariana de Souza E Silva
- Centro de Citricultura Sylvio Moreira, Instituto Agronômico-IAC, Cordeirópolis, SP 13490-970, Brazil
| | | | | | - Alessandra Alves de Souza
- Centro de Citricultura Sylvio Moreira, Instituto Agronômico-IAC, Cordeirópolis, SP 13490-970, Brazil
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15
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Hirakawa H, Suzue K, Takita A, Tomita H. Roles of OmpA in Type III Secretion System-Mediated Virulence of Enterohemorrhagic Escherichia coli. Pathogens 2021; 10:pathogens10111496. [PMID: 34832651 PMCID: PMC8622347 DOI: 10.3390/pathogens10111496] [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: 10/04/2021] [Revised: 11/11/2021] [Accepted: 11/14/2021] [Indexed: 11/17/2022] Open
Abstract
Outer membrane proteins are commonly produced by gram-negative bacteria, and they have diverse functions. A subgroup of proteins, which includes OmpA, OmpW and OmpX, is often involved in bacterial pathogenesis. Here we show that OmpA, rather than OmpW or OmpX, contributes to the virulence of enterohemorrhagic Escherichia coli (EHEC) through its type III secretion system (T3SS). Deletion of ompA decreased secretion of the T3SS proteins EspA and EspB; however, the expression level of the LEE genes that encode a set of T3SS proteins did not decrease. The ompA mutant had less abilities to form A/E lesions in host epithelial cells and lyse human red blood cells than the parent strain. Moreover, the virulence of an ompA mutant of Citrobacter rodentium (traditionally used to estimate T3SS-associated virulence in mice) was attenuated. Mice infected with the ompA mutant survived longer than those infected with the parent strain. Furthermore, mice infected with ompA developed symptoms of diarrhea more slowly than mice infected with the parent strain. Altogether, these results suggest that OmpA sustains the activity of the T3SS and is required for optimal virulence in EHEC. This work expands the roles of outer membrane proteins in bacterial pathogenesis.
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Affiliation(s)
- Hidetada Hirakawa
- Department of Bacteriology, Graduate School of Medicine, Gunma University, Maebashi 371-8511, Gunma, Japan; (A.T.); (H.T.)
- Correspondence: (H.H.); (K.S.)
| | - Kazutomo Suzue
- Department of Infectious Diseases and Host Defense, Graduate School of Medicine, Gunma University, Maebashi 371-8511, Gunma, Japan
- Correspondence: (H.H.); (K.S.)
| | - Ayako Takita
- Department of Bacteriology, Graduate School of Medicine, Gunma University, Maebashi 371-8511, Gunma, Japan; (A.T.); (H.T.)
| | - Haruyoshi Tomita
- Department of Bacteriology, Graduate School of Medicine, Gunma University, Maebashi 371-8511, Gunma, Japan; (A.T.); (H.T.)
- Laboratory of Bacterial Drug Resistance, Graduate School of Medicine, Gunma University, Maebashi 371-8511, Gunma, Japan
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16
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Sora VM, Meroni G, Martino PA, Soggiu A, Bonizzi L, Zecconi A. Extraintestinal Pathogenic Escherichia coli: Virulence Factors and Antibiotic Resistance. Pathogens 2021; 10:pathogens10111355. [PMID: 34832511 PMCID: PMC8618662 DOI: 10.3390/pathogens10111355] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/05/2021] [Accepted: 10/18/2021] [Indexed: 12/29/2022] Open
Abstract
The One Health approach emphasizes the importance of antimicrobial resistance (AMR) as a major concern both in public health and in food animal production systems. As a general classification, E. coli can be distinguished based on the ability to cause infection of the gastrointestinal system (IPEC) or outside of it (ExPEC). Among the different pathogens, E. coli are becoming of great importance, and it has been suggested that ExPEC may harbor resistance genes that may be transferred to pathogenic or opportunistic bacteria. ExPEC strains are versatile bacteria that can cause urinary tract, bloodstream, prostate, and other infections at non-intestinal sites. In this context of rapidly increasing multidrug-resistance worldwide and a diminishingly effective antimicrobial arsenal to tackle resistant strains. ExPEC infections are now a serious public health threat worldwide. However, the clinical and economic impact of these infections and their optimal management are challenging, and consequently, there is an increasing awareness of the importance of ExPECs amongst healthcare professionals and the general public alike. This review aims to describe pathotype characteristics of ExPEC to increase our knowledge of these bacteria and, consequently, to increase our chances to control them and reduce the risk for AMR, following a One Health approach.
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17
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Diwo M, Michel W, Aurass P, Kuhle-Keindorf K, Pippel J, Krausze J, Wamp S, Lang C, Blankenfeldt W, Flieger A. NAD(H)-mediated tetramerization controls the activity of Legionella pneumophila phospholipase PlaB. Proc Natl Acad Sci U S A 2021; 118:e2017046118. [PMID: 34074754 PMCID: PMC8201859 DOI: 10.1073/pnas.2017046118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The virulence factor PlaB promotes lung colonization, tissue destruction, and intracellular replication of Legionella pneumophila, the causative agent of Legionnaires' disease. It is a highly active phospholipase exposed at the bacterial surface and shows an extraordinary activation mechanism by tetramer deoligomerization. To unravel the molecular basis for enzyme activation and localization, we determined the crystal structure of PlaB in its tetrameric form. We found that the tetramer is a dimer of identical dimers, and a monomer consists of an N-terminal α/β-hydrolase domain expanded by two noncanonical two-stranded β-sheets, β-6/β-7 and β-9/β-10. The C-terminal domain reveals a fold displaying a bilobed β-sandwich with a hook structure required for dimer formation and structural complementation of the enzymatic domain in the neighboring monomer. This highlights the dimer as the active form. Δβ-9/β-10 mutants showed a decrease in the tetrameric fraction and altered activity profiles. The variant also revealed restricted binding to membranes resulting in mislocalization and bacterial lysis. Unexpectedly, we observed eight NAD(H) molecules at the dimer/dimer interface, suggesting that these molecules stabilize the tetramer and hence lead to enzyme inactivation. Indeed, addition of NAD(H) increased the fraction of the tetramer and concomitantly reduced activity. Together, these data reveal structural elements and an unprecedented NAD(H)-mediated tetramerization mechanism required for spatial and enzymatic control of a phospholipase virulence factor. The allosteric regulatory process identified here is suited to fine tune PlaB in a way that protects Legionella pneumophila from self-inflicted lysis while ensuring its activity at the pathogen-host interface.
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Affiliation(s)
- Maurice Diwo
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Wiebke Michel
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany
| | - Philipp Aurass
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany
| | - Katja Kuhle-Keindorf
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany
| | - Jan Pippel
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Joern Krausze
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Sabrina Wamp
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany
| | - Christina Lang
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany
| | - Wulf Blankenfeldt
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany;
- Institute for Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig, 38106 Braunschweig, Germany
| | - Antje Flieger
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, 38855 Wernigerode, Germany;
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18
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Scheller D, Twittenhoff C, Becker F, Holler M, Narberhaus F. OmpA, a Common Virulence Factor, Is Under RNA Thermometer Control in Yersinia pseudotuberculosis. Front Microbiol 2021; 12:687260. [PMID: 34220779 PMCID: PMC8245352 DOI: 10.3389/fmicb.2021.687260] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 04/21/2021] [Indexed: 11/13/2022] Open
Abstract
The outer membrane protein OmpA is a virulence factor in many mammalian pathogens. In previous global RNA structure probing studies, we found evidence for a temperature-modulated RNA structure in the 5'-untranslated region (5'-UTR) of the Yersinia pseudotuberculosis ompA transcript suggesting that opening of the structure at host-body temperature might relieve translational repression. Here, we support this hypothesis by quantitative reverse transcription PCR, translational reporter gene fusions, enzymatic RNA structure probing, and toeprinting assays. While ompA transcript levels decreased at 37°C compared to 25°C, translation of the transcript increased with increasing temperature. Biochemical experiments show that this is due to melting of the RNA structure, which permits ribosome binding to the 5'-UTR. A point mutation that locks the RNA structure in a closed conformation prevents translation by impairing ribosome access. Our findings add another common virulence factor to the growing list of pathogen-associated genes that are under RNA thermometer control.
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Affiliation(s)
- Daniel Scheller
- Department of Microbial Biology, Ruhr University Bochum, Bochum, Germany
| | | | - Franziska Becker
- Department of Microbial Biology, Ruhr University Bochum, Bochum, Germany
| | - Marcel Holler
- Department of Microbial Biology, Ruhr University Bochum, Bochum, Germany
| | - Franz Narberhaus
- Department of Microbial Biology, Ruhr University Bochum, Bochum, Germany
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19
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Ageorges V, Monteiro R, Leroy S, Burgess CM, Pizza M, Chaucheyras-Durand F, Desvaux M. Molecular determinants of surface colonisation in diarrhoeagenic Escherichia coli (DEC): from bacterial adhesion to biofilm formation. FEMS Microbiol Rev 2021; 44:314-350. [PMID: 32239203 DOI: 10.1093/femsre/fuaa008] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 03/31/2020] [Indexed: 12/11/2022] Open
Abstract
Escherichia coli is primarily known as a commensal colonising the gastrointestinal tract of infants very early in life but some strains being responsible for diarrhoea, which can be especially severe in young children. Intestinal pathogenic E. coli include six pathotypes of diarrhoeagenic E. coli (DEC), namely, the (i) enterotoxigenic E. coli, (ii) enteroaggregative E. coli, (iii) enteropathogenic E. coli, (iv) enterohemorragic E. coli, (v) enteroinvasive E. coli and (vi) diffusely adherent E. coli. Prior to human infection, DEC can be found in natural environments, animal reservoirs, food processing environments and contaminated food matrices. From an ecophysiological point of view, DEC thus deal with very different biotopes and biocoenoses all along the food chain. In this context, this review focuses on the wide range of surface molecular determinants acting as surface colonisation factors (SCFs) in DEC. In the first instance, SCFs can be broadly discriminated into (i) extracellular polysaccharides, (ii) extracellular DNA and (iii) surface proteins. Surface proteins constitute the most diverse group of SCFs broadly discriminated into (i) monomeric SCFs, such as autotransporter (AT) adhesins, inverted ATs, heat-resistant agglutinins or some moonlighting proteins, (ii) oligomeric SCFs, namely, the trimeric ATs and (iii) supramolecular SCFs, including flagella and numerous pili, e.g. the injectisome, type 4 pili, curli chaperone-usher pili or conjugative pili. This review also details the gene regulatory network of these numerous SCFs at the various stages as it occurs from pre-transcriptional to post-translocational levels, which remains to be fully elucidated in many cases.
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Affiliation(s)
- Valentin Ageorges
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | - Ricardo Monteiro
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France.,GSK, Via Fiorentina 1, 53100 Siena, Italy
| | - Sabine Leroy
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | - Catherine M Burgess
- Food Safety Department, Teagasc Food Research Centre, Ashtown, Dublin 15, Ireland
| | | | - Frédérique Chaucheyras-Durand
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France.,Lallemand Animal Nutrition SAS, F-31702 Blagnac Cedex, France
| | - Mickaël Desvaux
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
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20
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Ayerbe-Algaba R, Bayó N, Verdú E, Parra-Millán R, Seco J, Teixidó M, Pachón J, Giralt E, Smani Y. AOA-2 Derivatives as Outer Membrane Protein A Inhibitors for Treatment of Gram-Negative Bacilli Infections. Front Microbiol 2021; 12:634323. [PMID: 33643267 PMCID: PMC7907166 DOI: 10.3389/fmicb.2021.634323] [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: 11/27/2020] [Accepted: 01/21/2021] [Indexed: 12/11/2022] Open
Abstract
Previously, we identified that a cyclic hexapeptide AOA-2 inhibited the interaction of Gram-negative bacilli (GNB) like Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli to host cells thereby preventing the development of infection in vitro and in a murine sepsis peritoneal model. In this work, we aimed to evaluate in vitro a library of AOA-2 derivatives in order to improve the effect of AOA-2 against GNB infections. Ten AOA-2 derivatives were synthetized for the in vitro assays. Their toxicities to human lung epithelial cells (A549 cells) for 24 h were evaluated by determining the A549 cells viability using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The effect of these peptide derivatives and AOA-2 at 250, 125, 62.5, and 31.25 μg/mL on the attachment of A. baumannii ATCC 17978, P. aeruginosa PAO1 and E. coli ATCC 25922 strains to A549 cells was characterized by adherence and viability assays. None of the 10 derivatives showed toxicity to A549 cells. RW01 and RW06 have reduced more the adherence of ATCC 17978, PAO1 and ATCC 2599 strains to A549 cells when compared with the original compound AOA-2. Moreover, both peptides have increased slightly the viability of infected A549 cells by PAO1 and ATCC 25922 than those observed with AOA-2. Finally, RW01 and RW06 have potentiated the activity of colistin against ATCC 17978 strain in the same level with AOA-2. The optimization program of AOA-2 has generated two derivatives (RW01 and RW06) with best effect against interaction of GNB with host cells, specifically against P. aeruginosa and E. coli.
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Affiliation(s)
- Rafael Ayerbe-Algaba
- Clinical Unit of Infectious Diseases, Microbiology and Preventive Medicine, University Hospital Virgen del Rocío, Seville, Spain.,Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
| | - Nuria Bayó
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - Ester Verdú
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - Raquel Parra-Millán
- Clinical Unit of Infectious Diseases, Microbiology and Preventive Medicine, University Hospital Virgen del Rocío, Seville, Spain.,Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
| | - Jesús Seco
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - Meritxell Teixidó
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - Jerónimo Pachón
- Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain.,Department of Medicine, University of Seville, Seville, Spain
| | - Ernest Giralt
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute for Science and Technology (BIST), Barcelona, Spain.,Department of Inorganic and Organic Chemistry, University of Barcelona, Barcelona, Spain
| | - Younes Smani
- Clinical Unit of Infectious Diseases, Microbiology and Preventive Medicine, University Hospital Virgen del Rocío, Seville, Spain.,Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/Spanish National Research Council (CSIC)/University of Seville, Seville, Spain
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21
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Diversification of OmpA and OmpF of Yersinia ruckeri is independent of the underlying species phylogeny and evidence of virulence-related selection. Sci Rep 2021; 11:3493. [PMID: 33568758 PMCID: PMC7876001 DOI: 10.1038/s41598-021-82925-7] [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: 05/08/2020] [Accepted: 01/27/2021] [Indexed: 01/30/2023] Open
Abstract
Yersinia ruckeri is the causative agent of enteric redmouth disease (ERM) which causes economically significant losses in farmed salmonids, especially Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss, Walbaum). However, very little is known about the genetic relationships of disease-causing isolates in these two host species or about factors responsible for disease. Phylogenetic analyses of 16 representative isolates based on the nucleotide sequences of 19 housekeeping genes suggests that pathogenic Atlantic salmon and rainbow trout isolates represent distinct host-specific lineages. However, the apparent phylogenies of certain isolates has been influenced by horizontal gene transfer and recombinational exchange. Splits decomposition analysis demonstrated a net-like phylogeny based on the housekeeping genes, characteristic of recombination. Comparative analysis of the distribution of individual housekeeping gene alleles across the isolates demonstrated evidence of genomic mosaicism and recombinational exchange involving certain Atlantic salmon and rainbow trout isolates. Comparative nucleotide sequence analysis of the key outer membrane protein genes ompA and ompF revealed that the corresponding gene trees were both non-congruent with respect to the housekeeping gene phylogenies providing evidence that horizontal gene transfer has influenced the evolution of both these surface protein-encoding genes. Analysis of inferred amino acid sequence variation in OmpA identified a single variant, OmpA.1, that was present in serotype O1 and O8 isolates representing typical pathogenic strains in rainbow trout and Atlantic salmon, respectively. In particular, the sequence of surface-exposed loop 3 differed by seven amino acids to that of other Y. ruckeri isolates. These findings suggest that positive selection has likely influenced the presence of OmpA.1 in these isolates and that loop 3 may play an important role in virulence. Amino acid sequence variation of OmpF was greater than that of OmpA and was similarly restricted mainly to the surface-exposed loops. Two OmpF variants, OmpF.1 and OmpF.2, were associated with pathogenic rainbow trout and Atlantic salmon isolates, respectively. These OmpF proteins had very similar amino acid sequences suggesting that positive evolutionary pressure has also favoured the selection of these variants in pathogenic strains infecting both species.
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22
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Searching for putative virulence factors in the genomes of Shewanella indica and Shewanella algae. Arch Microbiol 2020; 203:683-692. [PMID: 33040180 DOI: 10.1007/s00203-020-02060-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/12/2020] [Accepted: 09/30/2020] [Indexed: 12/16/2022]
Abstract
Bacterial pathogens are a major threat to both humans and animals worldwide. It is crucial to understand the mechanisms of various disease processes at the molecular level. Shewanella species are widespread in the environment and some are considered as emerging opportunistic human and marine mammal pathogens. In this study, putative virulence factors on the genome of Shewanella indica BW, a bacterium isolated from the Bryde's whale (Balaenoptera edeni), were determined. Additionally, for comparative purposes, putative virulence factors from two other S. indica and ten S. algae strains were also determined using the Pathosystems Resource Integration Center (PATRIC) pipeline. We confirmed the presence of previously reported virulence factors and we are proposing several new candidate virulence factors. Interestingly, the putative virulence factors were very similar between the two species with the exception of microbial collagenase which was present in all S. algae genomes, but absent in all S. indica genomes.
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23
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Desvaux M, Dalmasso G, Beyrouthy R, Barnich N, Delmas J, Bonnet R. Pathogenicity Factors of Genomic Islands in Intestinal and Extraintestinal Escherichia coli. Front Microbiol 2020; 11:2065. [PMID: 33101219 PMCID: PMC7545054 DOI: 10.3389/fmicb.2020.02065] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 08/05/2020] [Indexed: 12/20/2022] Open
Abstract
Escherichia coli is a versatile bacterial species that includes both harmless commensal strains and pathogenic strains found in the gastrointestinal tract in humans and warm-blooded animals. The growing amount of DNA sequence information generated in the era of "genomics" has helped to increase our understanding of the factors and mechanisms involved in the diversification of this bacterial species. The pathogenic side of E. coli that is afforded through horizontal transfers of genes encoding virulence factors enables this bacterium to become a highly diverse and adapted pathogen that is responsible for intestinal or extraintestinal diseases in humans and animals. Many of the accessory genes acquired by horizontal transfers form syntenic blocks and are recognized as genomic islands (GIs). These genomic regions contribute to the rapid evolution, diversification and adaptation of E. coli variants because they are frequently subject to rearrangements, excision and transfer, as well as to further acquisition of additional DNA. Here, we review a subgroup of GIs from E. coli termed pathogenicity islands (PAIs), a concept defined in the late 1980s by Jörg Hacker and colleagues in Werner Goebel's group at the University of Würzburg, Würzburg, Germany. As with other GIs, the PAIs comprise large genomic regions that differ from the rest of the genome by their G + C content, by their typical insertion within transfer RNA genes, and by their harboring of direct repeats (at their ends), integrase determinants, or other mobility loci. The hallmark of PAIs is their contribution to the emergence of virulent bacteria and to the development of intestinal and extraintestinal diseases. This review summarizes the current knowledge on the structure and functional features of PAIs, on PAI-encoded E. coli pathogenicity factors and on the role of PAIs in host-pathogen interactions.
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Affiliation(s)
- Mickaël Desvaux
- Université Clermont Auvergne, INRAE, MEDiS, Clermont-Ferrand, France
| | - Guillaume Dalmasso
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Racha Beyrouthy
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
- Laboratoire de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - Nicolas Barnich
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Julien Delmas
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
- Laboratoire de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - Richard Bonnet
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
- Laboratoire de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
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24
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Ribosome Display Technology: Applications in Disease Diagnosis and Control. Antibodies (Basel) 2020; 9:antib9030028. [PMID: 32605027 PMCID: PMC7551589 DOI: 10.3390/antib9030028] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/06/2020] [Accepted: 06/08/2020] [Indexed: 12/28/2022] Open
Abstract
Antibody ribosome display remains one of the most successful in vitro selection technologies for antibodies fifteen years after it was developed. The unique possibility of direct generation of whole proteins, particularly single-chain antibody fragments (scFvs), has facilitated the establishment of this technology as one of the foremost antibody production methods. Ribosome display has become a vital tool for efficient and low-cost production of antibodies for diagnostics due to its advantageous ability to screen large libraries and generate binders of high affinity. The remarkable flexibility of this method enables its applicability to various platforms. This review focuses on the applications of ribosome display technology in biomedical and agricultural fields in the generation of recombinant scFvs for disease diagnostics and control.
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25
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Nielsen DW, Ricker N, Barbieri NL, Allen HK, Nolan LK, Logue CM. Outer membrane protein A (OmpA) of extraintestinal pathogenic Escherichia coli. BMC Res Notes 2020; 13:51. [PMID: 32005127 PMCID: PMC6995065 DOI: 10.1186/s13104-020-4917-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/22/2020] [Indexed: 02/05/2023] Open
Abstract
Objective Extraintestinal Pathogenic E. coli (ExPEC), are responsible for host diseases such as Neonatal Meningitis Escherichia coli (NMEC), the second-leading cause of neonatal bacterial meningitis, Avian Pathogenic E. coli (APEC), a cause of extraintestinal disease in poultry, and Uropathogenic E. coli (UPEC), the most common cause of urinary tract infections. Virulence factors associated with NMEC include outer membrane protein A (OmpA) and type I fimbriae (FimH), which also occur in APEC and UPEC. OmpA contributes to NMEC’s ability to cross the blood–brain barrier, persist in the bloodstream and has been identified as a potential vaccine target for ExPEC, however the protein has amino acid variants, which may influence virulence of strains or alter vaccine efficacy. Although OmpA is present in virtually all E. coli, differences in its amino acid residues have yet to be surveyed in ExPEC. Results Here the ompA gene (n = 399) from ExPEC collections were sequenced and translated in silico. Twenty-five different OmpA polymorphism patterns were identified. Seven polymorphism patterns were significantly associated with an ExPEC subpathotype, but chromosomal history most likely accounts for most differences found. The differences in OmpA protein sequences suggest that OmpA may influence variation in virulence and host specificity within ExPEC subpathotypes.
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Affiliation(s)
- Daniel W Nielsen
- Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, 1802 University Blvd, Ames, IA, 50011, USA.,Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, ARS-USDA, Ames, IA, USA
| | - Nicole Ricker
- Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, ARS-USDA, Ames, IA, USA.,Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Nicolle L Barbieri
- Department of Population Health, College of Veterinary Medicine, University of Georgia, 501 D.W. Brooks Drive, Athens, GA, 30602, USA
| | - Heather K Allen
- Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, ARS-USDA, Ames, IA, USA
| | - Lisa K Nolan
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, 30602, USA
| | - Catherine M Logue
- Department of Population Health, College of Veterinary Medicine, University of Georgia, 501 D.W. Brooks Drive, Athens, GA, 30602, USA.
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26
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Kim KS. Investigating Bacterial Penetration of the Blood-Brain Barrier for the Pathogenesis, Prevention, and Therapy of Bacterial Meningitis. ACS Infect Dis 2020; 6:34-42. [PMID: 31805229 DOI: 10.1021/acsinfecdis.9b00319] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The most distressing aspect of bacterial meningitis is limited improvement in the mortality and morbidity despite attributable advances in antimicrobial chemotherapy and supportive care. A major contributing factor to such mortality and morbidity is our incomplete understanding of the pathogenesis of this disease. Microbial penetration of the blood-brain barrier, a prerequisite for the development of bacterial meningitis, exploits specific host and bacterial factors as well as host cell signaling molecules. Determination and characterization of such host and bacterial factors have been instrumental for developing our current knowledge on the pathogenesis of bacterial meningitis. In addition, counteracting such host and microbial factors has been shown to be efficacious in the prevention of bacterial meningitis. Antimicrobial therapy alone has limited efficacy in improving the outcome of bacterial meningitis. Recent studies suggest that counteracting targets contributing to bacterial penetration of the blood-brain barrier are a beneficial therapeutic adjunct to antimicrobial therapy in improving the outcome of bacterial meningitis. Taken together, these findings indicate that the elucidation of host and bacterial factors contributing to microbial penetration of the blood-brain barrier provides a novel strategy for investigating the pathogenesis, prevention, and therapy of bacterial meningitis.
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Affiliation(s)
- Kwang Sik Kim
- Division of Pediatric Infectious Diseases, Johns Hopkins University School of Medicine, 200 North Wolfe Street, Room 3157, Baltimore, Maryland 21287, United States
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27
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Li C, Yin W, Yu N, Zhang D, Zhao H, Liu J, Liu J, Pan Y, Lin L. miR-155 promotes macrophage pyroptosis induced by Porphyromonas gingivalis through regulating the NLRP3 inflammasome. Oral Dis 2019; 25:2030-2039. [PMID: 31529565 DOI: 10.1111/odi.13198] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 07/26/2019] [Accepted: 09/11/2019] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The aim of this study is to detect pyroptosis in macrophages stimulated with Porphyromonas gingivalis and elucidate the mechanism by which P. gingivalis induces pyroptosis in macrophages. METHODS The immortalized human monocyte cell line U937 was stimulated with P. gingivalis W83. Flow cytometry was carried out to detect pyroptosis in macrophages. The expression of miR-155 was detected by real-time PCR and inhibited using RNAi. Suppressor of cytokine signaling (SOCS) 1, cleaved GSDMD, caspase (CAS)-1, caspase-11, apoptosis-associated speck-like protein (ASC), and NOD-like receptor protein 3 (NLRP3) were detected by Western blotting, and IL-1β and IL-18 were detected by ELISA. RESULTS The rate of pyroptosis in macrophages and the expression of miR-155 increased upon stimulation with P. gingivalis and pyroptosis rate decreased when miR-155 was silenced. GSDMD-NT, CAS-11, CAS-1, ASC, NLRP3, IL-1β, and IL-18 levels increased, but SOCS1 decreased in U937 cells after stimulated with P. gingivalis. These changes were weakened in P. gingivalis-stimulated U937 macrophages transfected with lentiviruses carrying miR-155 shRNA compared to those transfected with non-targeting control sequence. However, there was no significant difference in ASC expression between P. gingivalis-stimulated shCont and shMiR-155 cells. CONCLUSIONS Porphyromonas gingivalis promotes pyroptosis in macrophages during early infection. miR-155 is involved in this process through regulating the NLRP3 inflammasome.
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Affiliation(s)
- Chen Li
- Department of Periodontics, School of Stomatology, China Medical University, Shenyang, China
| | - Wanting Yin
- Department of Periodontics, School of Stomatology, China Medical University, Shenyang, China.,MALO CLINIC, Shenyang, China
| | - Ning Yu
- Department of Periodontics and Oral Medicine, University of Michigan at Ann Arbor, MI, USA
| | - Dongmei Zhang
- Department of Periodontics, School of Stomatology, China Medical University, Shenyang, China.,Liaoning Province Key Laboratory of Oral Diseases, Shenyang, China
| | - Haijiao Zhao
- Department of Periodontics, School of Stomatology, China Medical University, Shenyang, China
| | - Jingbo Liu
- Department of Periodontics, School of Stomatology, China Medical University, Shenyang, China
| | - Junchao Liu
- Department of Periodontics, School of Stomatology, China Medical University, Shenyang, China.,Liaoning Province Translational Medicine Research Center of Oral Diseases, Shenyang, China
| | - Yaping Pan
- Department of Periodontics, School of Stomatology, China Medical University, Shenyang, China
| | - Li Lin
- Department of Periodontics, School of Stomatology, China Medical University, Shenyang, China
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28
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Geisinger E, Huo W, Hernandez-Bird J, Isberg RR. Acinetobacter baumannii: Envelope Determinants That Control Drug Resistance, Virulence, and Surface Variability. Annu Rev Microbiol 2019; 73:481-506. [DOI: 10.1146/annurev-micro-020518-115714] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Acinetobacter baumannii has emerged as an important nosocomial pathogen, particularly for patients in intensive care units and with invasive indwelling devices. The most recent clinical isolates are resistant to several classes of clinically important antibiotics, greatly restricting the ability to effectively treat critically ill patients. The bacterial envelope is an important driver of A. baumannii disease, both at the level of battling against antibiotic therapy and at the level of protecting from host innate immune function. This review provides a comprehensive overview of key features of the envelope that interface with both the host and antimicrobial therapies. Carbohydrate structures that contribute to protecting from the host are detailed, and mutations that alter these structures, resulting in increased antimicrobial resistance, are explored. In addition, protein complexes involved in both intermicrobial and host-microbe interactions are described. Finally we discuss regulatory mechanisms that control the nature of the cell envelope and its impact on host innate immune function.
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Affiliation(s)
- Edward Geisinger
- Department of Biology, Northeastern University, Boston, Massachusetts 02115, USA
| | - Wenwen Huo
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
| | - Juan Hernandez-Bird
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
| | - Ralph R. Isberg
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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29
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Pushing beyond the Envelope: the Potential Roles of OprF in Pseudomonas aeruginosa Biofilm Formation and Pathogenicity. J Bacteriol 2019; 201:JB.00050-19. [PMID: 31010902 DOI: 10.1128/jb.00050-19] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The ability of Pseudomonas aeruginosa to form biofilms, which are communities of cells encased in a self-produced extracellular matrix, protects the cells from antibiotics and the host immune response. While some biofilm matrix components, such as exopolysaccharides and extracellular DNA, are relatively well characterized, the extracellular matrix proteins remain understudied. Multiple proteomic analyses of the P. aeruginosa soluble biofilm matrix and outer membrane vesicles, which are a component of the matrix, have identified OprF as an abundant matrix protein. To date, the few reports on the effects of oprF mutations on biofilm formation are conflicting, and little is known about the potential role of OprF in the biofilm matrix. The majority of OprF studies focus on the protein as a cell-associated porin. As a component of the outer membrane, OprF assumes dual conformations and is involved in solute transport, as well as cell envelope integrity. Here, we review the current literature on OprF in P. aeruginosa, discussing how the structure and function of the cell-associated and matrix-associated protein may affect biofilm formation and pathogenesis in order to inform future research on this understudied matrix protein.
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30
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Rose R, Häuser S, Stump-Guthier C, Weiss C, Rohde M, Kim KS, Ishikawa H, Schroten H, Schwerk C, Adam R. Virulence factor-dependent basolateral invasion of choroid plexus epithelial cells by pathogenic Escherichia coli in vitro. FEMS Microbiol Lett 2019; 365:5195518. [PMID: 30476042 DOI: 10.1093/femsle/fny274] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 11/20/2018] [Indexed: 12/18/2022] Open
Abstract
Escherichia coli is the most common Gram-negative causative agent of neonatal meningitis and E. coli meningitis is associated with high morbidity and mortality. Previous research has been carried out with regard to the blood-brain barrier and thereby unveiled an assortment of virulence factors involved in E. coli meningitis. Little, however, is known about the role of the blood-cerebrospinal fluid (CSF) barrier (BCSFB), in spite of several studies suggesting that the choroid plexus (CP) is a possible entry point for E. coli into the CSF spaces. Here, we used a human CP papilloma (HIBCPP) cell line that was previously established as valid model for the study of the BCSFB. We show that E. coli invades HIBCPP cells in a polar fashion preferentially from the physiologically relevant basolateral side. Moreover, we demonstrate that deletion of outer membrane protein A, ibeA or neuDB genes results in decreased cell infection, while absence of fimH enhances invasion, although causing reduced adhesion to the apical side of HIBCPP cells. Our findings suggest that the BCSFB might constitute an entry point for E. coli into the central nervous system, and HIBCPP cells are a valuable tool for investigating E. coli entry of the BCSFB.
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Affiliation(s)
- Rebekah Rose
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
| | - Svenja Häuser
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
| | - Carolin Stump-Guthier
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
| | - Christel Weiss
- Department of Medical Statistics and Biomathematics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, D-38124 Braunschweig, Germany
| | - Kwang Sik Kim
- Division of Pediatric Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Hiroshi Ishikawa
- Laboratory of Clinical Regenerative Medicine, Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, 1-1-1Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Horst Schroten
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
| | - Christian Schwerk
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
| | - Rüdiger Adam
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
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31
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Mwale PF, Lee CH, Leu SJ, Lee YC, Wu HH, Lin LT, Lin TE, Huang YJ, Yang YY. Antigenic epitopes on the outer membrane protein A of Escherichia coli identified with single-chain variable fragment (scFv) antibodies. Appl Microbiol Biotechnol 2019; 103:5285-5299. [PMID: 31028439 DOI: 10.1007/s00253-019-09761-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 03/07/2019] [Accepted: 03/10/2019] [Indexed: 10/26/2022]
Abstract
Bacterial meningitis is a severe disease that is fatal to one-third of patients. The major cause of meningitis in neonates is Escherichia coli (E. coli) K1. This bacterium synthesizes an outer membrane protein A (OmpA) that is responsible for the adhesion to (and invasion of) endothelial cells. Thus, the OmpA protein represents a potential target for developing diagnostic and therapeutic agents for meningitis. In this study, we expressed recombinant OmpA proteins with various molecular weights in E. coli. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was performed to check the molecular size of OmpA's full length (FL) and truncated proteins. OmpA-FL protein was purified for immunizing chickens to produce immunoglobulin yolk (IgY) antibodies. We applied phage display technology to construct antibody libraries (OmpA-FL scFv-S 1.1 × 107 and OmpA-FL scFv-L 5.01 × 106) to select specific anti-OmpA-FL scFv antibodies; these were characterized by their binding ability to recombinant or endogenous OmpA using ELISA, immunofluorescent staining, and confirmed with immunoblotting. We found 12 monoclonal antibodies that react to OmpA fragments; seven scFvs recognize fragments spanning amino acid (aa) residues 1-346, aa 1-287, aa 1-167, and aa 60-192, while five scFvs recognize fragments spanning aa 1-346 and aa 1-287 only. Two fragments (aa 246-346 and aa 287-346) were not recognized with any of the 12 scFvs. Together, the data suggest three antigenic epitopes (60 aa-160 aa, 161 aa-167 aa, 193 aa-245 aa) recognized by monoclonal antibodies. These scFv antibodies show strong reactivity against OmpA proteins. We believe that antibodies show promising diagnostic agents for E. coli K1 meningitis.
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Affiliation(s)
- Pharaoh Fellow Mwale
- Ph.D. Program in Medical Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.,School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, #250 Wu-Hsing Street, Taipei, Taiwan, 110
| | - Chi-Hsin Lee
- Ph.D. Program in Medical Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.,School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, #250 Wu-Hsing Street, Taipei, Taiwan, 110
| | - Sy-Jye Leu
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yu-Ching Lee
- The Center of Translational Medicine, Taipei Medical University, Taipei, Taiwan
| | - Hsueh-Hsia Wu
- Ph.D. Program in Medical Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.,School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, #250 Wu-Hsing Street, Taipei, Taiwan, 110
| | - Liang-Tzung Lin
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Tony Eight Lin
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Yun-Ju Huang
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, #250 Wu-Hsing Street, Taipei, Taiwan, 110
| | - Yi-Yuan Yang
- Ph.D. Program in Medical Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan. .,School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, #250 Wu-Hsing Street, Taipei, Taiwan, 110. .,Core Laboratory of Antibody Generation and Research, Taipei Medical University, Taipei, Taiwan.
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32
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Konradt C, Hunter CA. Pathogen interactions with endothelial cells and the induction of innate and adaptive immunity. Eur J Immunol 2018; 48:1607-1620. [PMID: 30160302 DOI: 10.1002/eji.201646789] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 07/24/2018] [Accepted: 08/23/2018] [Indexed: 12/28/2022]
Abstract
There are over 10 trillion endothelial cells (EC) that line the vasculature of the human body. These cells not only have specialized functions in the maintenance of homeostasis within the circulation and various tissues but they also have a major role in immune function. EC also represent an important replicative niche for a subset of viral, bacterial, and parasitic organisms that are present in the blood or lymph; however, there are major gaps in our knowledge regarding how pathogens interact with EC and how this influences disease outcome. In this article, we review the literature on EC-pathogen interactions and their role in innate and adaptive mechanisms of resistance to infection and highlight opportunities to address prominent knowledge gaps.
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Affiliation(s)
- Christoph Konradt
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Christopher A Hunter
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
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33
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Evaluation of Lsa46 and Lsa77 Leptospiral Proteins for Their Immunoprotective Activities in Hamster Model of Leptospirosis. BIOMED RESEARCH INTERNATIONAL 2018; 2018:1813745. [PMID: 29984227 PMCID: PMC6015724 DOI: 10.1155/2018/1813745] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 05/13/2018] [Indexed: 11/18/2022]
Abstract
Leptospirosis is a neglected tropical disease caused by pathogenic Leptospira spp. The lack of an effective vaccine favors the increase of the disease. Currently, surface-exposed proteins are the main targets for the search of vaccine candidates. In this study, we examined whether the surface Lsa46 and Lsa77 proteins, previously identified as laminin and plasminogen binding proteins, have the capacity of inducing protection and sterilizing immunity against challenge with virulent Leptospira in hamster model. Animals were subcutaneously immunized with Lsa46, Lsa77, or a combination of both in Alum adjuvant and challenged intraperitoneally with L. interrogans serovar Kennewicki strain Pomona Fromm. Hamster immunization with Lsa46 or Lsa77 or both promoted a strong IgG response. Th2- and Th1-biased immune responses were observed when Lsa46 and Lsa77 were individually administered, respectively, as detected by the IgG1/IgG2/3 ratio. Immunized hamsters with the combined proteins induced a Th1-biased immune response. Although the immunization with Lsa46 and Lsa77 stimulated protective immunity with reduction of bacterial burden, when compared to animals individually immunized with the proteins, the data was not statistically significant. Thus, although promising, more studies are needed before the role of these proteins in stimulating sterilizing immunity in mammals is conclusively determined.
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34
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Zhao WD, Liu DX, Wei JY, Miao ZW, Zhang K, Su ZK, Zhang XW, Li Q, Fang WG, Qin XX, Shang DS, Li B, Li QC, Cao L, Kim KS, Chen YH. Caspr1 is a host receptor for meningitis-causing Escherichia coli. Nat Commun 2018; 9:2296. [PMID: 29895952 PMCID: PMC5997682 DOI: 10.1038/s41467-018-04637-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 05/03/2018] [Indexed: 12/17/2022] Open
Abstract
Escherichia coli is the leading cause of neonatal Gram-negative bacterial meningitis, but the pathogenesis of E. coli meningitis remains elusive. E. coli penetration of the blood–brain barrier (BBB) is the critical step for development of meningitis. Here, we identify Caspr1, a single-pass transmembrane protein, as a host receptor for E. coli virulence factor IbeA to facilitate BBB penetration. Genetic ablation of endothelial Caspr1 and blocking IbeA–Caspr1 interaction effectively prevent E. coli penetration into the brain during meningitis in rodents. IbeA interacts with extracellular domain of Caspr1 to activate focal adhesion kinase signaling causing E. coli internalization into the brain endothelial cells of BBB. E. coli can invade hippocampal neurons causing apoptosis dependent on IbeA–Caspr1 interaction. Our results indicate that E. coli exploits Caspr1 as a host receptor for penetration of BBB resulting in meningitis, and that Caspr1 might be a useful target for prevention or therapy of E. coli meningitis. Penetration of the blood–brain barrier (BBB) is crucial for development of E. coli-caused meningitis. Here, the authors show that a host membrane protein, Caspr1, acts as a receptor for a bacterial virulence factor to facilitate BBB penetration and entry of E. coli into brain neurons.
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Affiliation(s)
- Wei-Dong Zhao
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China.
| | - Dong-Xin Liu
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Jia-Yi Wei
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Zi-Wei Miao
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Ke Zhang
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Zheng-Kang Su
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Xue-Wei Zhang
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Qiang Li
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Wen-Gang Fang
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Xiao-Xue Qin
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - De-Shu Shang
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Bo Li
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Qing-Chang Li
- Department of Pathology, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Liu Cao
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China
| | - Kwang Sik Kim
- Division of Pediatric Infectious Diseases, Johns Hopkins University School of Medicine, 200 North Wolfe St, Room 3157, Baltimore, MD, 21287, USA
| | - Yu-Hua Chen
- Department of Developmental Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 77 Puhe Road, Shenbei New District, 110122, Shenyang, China.
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Gu H, Liao Y, Zhang J, Wang Y, Liu Z, Cheng P, Wang X, Zou Q, Gu J. Rational Design and Evaluation of an Artificial Escherichia coli K1 Protein Vaccine Candidate Based on the Structure of OmpA. Front Cell Infect Microbiol 2018; 8:172. [PMID: 29876324 PMCID: PMC5974202 DOI: 10.3389/fcimb.2018.00172] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 05/04/2018] [Indexed: 12/12/2022] Open
Abstract
Escherichia coli (E. coli) K1 causes meningitis and remains an unsolved problem in neonates, despite the application of antibiotics and supportive care. The cross-reactivity of bacterial capsular polysaccharides with human antigens hinders their application as vaccine candidates. Thus, protein antigens could be an alternative strategy for the development of an E. coli K1 vaccine. Outer membrane protein A (OmpA) of E. coli K1 is a potential vaccine candidate because of its predominant contribution to bacterial pathogenesis and sub-cellular localization. However, little progress has been made regarding the use of OmpA for this purpose due to difficulties in OmpA production. In the present study, we first investigated the immunogenicity of the four extracellular loops of OmpA. Using the structure of OmpA, we rationally designed and successfully generated the artificial protein OmpAVac, composed of connected loops from OmpA. Recombinant OmpAVac was successfully produced in E. coli BL21 and behaved as a soluble homogenous monomer in the aqueous phase. Vaccination with OmpAVac induced Th1, Th2, and Th17 immune responses and conferred effective protection in mice. In addition, OmpAVac-specific antibodies were able to mediate opsonophagocytosis and inhibit bacterial invasion, thereby conferring prophylactic protection in E. coli K1-challenged adult mice and neonatal mice. These results suggest that OmpAVac could be a good vaccine candidate for the control of E. coli K1 infection and provide an additional example of structure-based vaccine design.
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Affiliation(s)
- Hao Gu
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China
| | - Yaling Liao
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China
| | - Jin Zhang
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China.,Department of Critical Care Medicine, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Ying Wang
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China
| | - Zhiyong Liu
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Ping Cheng
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China
| | - Xingyong Wang
- Department of Critical Care Medicine, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Quanming Zou
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China
| | - Jiang Gu
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China
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36
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Jeiranikhameneh M, Razavi MR, Irani S, Siadat SD, Oloomi M. Designing novel construction for cell surface display of protein E on Escherichia coli using non-classical pathway based on Lpp-OmpA. AMB Express 2017; 7:53. [PMID: 28247289 PMCID: PMC5331024 DOI: 10.1186/s13568-017-0350-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 02/20/2017] [Indexed: 01/30/2023] Open
Abstract
Today, transference of recombinant protein on the outer surface of bacteria is deemed as a valuable process for various applications in biotechnology including preparation of vaccines. In this study, Lpp-OmpA structure was used to present outer membrane protein E of Haemophilus influenzae on E. coli outer membrane. Also, a structure was designed according to Lpp-OmpA based on non-classical secretion pathway using bioinformatics software such as MEMSAT-SVM, ScrotumP and SignalP where it lacked any signal peptide at its N-terminal. Potential of this structure in the presentation of protein E on the surface of E. coli through non-classical pathway was indicated by western blotting, SDS page and fluorescent microscopy techniques, similarly its effectiveness was compared with Lpp-OmpA system. The results of the current study showed that the new structure had higher efficiency than Lpp-OmpA, and it could transport protein E on outer membrane well. This study is the first report in the presentation of H. influenzae PE onto the surface of E. coli by Lpp-OmpA, and the structure originated from Lpp-OmpA, according to the non-classical secretion pathway. Our results suggest that non-classical secretion pathway may be exploited as a new secretory pathway on the outer surface of the cell for recombinant proteins.
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37
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Role of outer membrane protein T in pathogenicity of avian pathogenic Escherichia coli. Res Vet Sci 2017; 115:109-116. [DOI: 10.1016/j.rvsc.2017.01.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 01/18/2017] [Accepted: 01/26/2017] [Indexed: 11/19/2022]
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38
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Abstract
Escherichia coli is the most common Gram-negative bacillary organism causing meningitis, and E. coli meningitis continues to be an important cause of mortality and morbidity throughout the world. Our incomplete knowledge of its pathogenesis contributes to such mortality and morbidity. Recent reports of E. coli strains producing CTX-M-type or TEM-type extended-spectrum β-lactamases create a challenge. Studies using in vitro and in vivo models of the blood-brain barrier have shown that E. coli meningitis follows a high degree of bacteremia and invasion of the blood-brain barrier. E. coli invasion of the blood-brain barrier, the essential step in the development of E. coli meningitis, requires specific microbial and host factors as well as microbe- and host-specific signaling molecules. Blockade of such microbial and host factors contributing to E. coli invasion of the blood-brain barrier is shown to be efficient in preventing E. coli penetration into the brain. The basis for requiring a high degree of bacteremia for E. coli penetration of the blood-brain barrier, however, remains unclear. Continued investigation on the microbial and host factors contributing to a high degree of bacteremia and E. coli invasion of the blood-brain barrier is likely to identify new targets for prevention and therapy of E. coli meningitis.
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39
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Baseer S, Ahmad S, Ranaghan KE, Azam SS. Towards a peptide-based vaccine against Shigella sonnei : A subtractive reverse vaccinology based approach. Biologicals 2017; 50:87-99. [DOI: 10.1016/j.biologicals.2017.08.004] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Revised: 07/11/2017] [Accepted: 08/08/2017] [Indexed: 02/06/2023] Open
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40
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Genome sequence of lung pathogenic Escherichia coli O78, a chimeric strain isolated from pneumonia forest musk deer. Genes Genomics 2017. [DOI: 10.1007/s13258-017-0545-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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41
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Comparison of gene expression among normally divided cells, elongated cells, spheroplasts at the beginning of growth, and enlarged spheroplasts at 43 h of growth in Lelliottia amnigena. GENE REPORTS 2017. [DOI: 10.1016/j.genrep.2017.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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42
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Breland EJ, Eberly AR, Hadjifrangiskou M. An Overview of Two-Component Signal Transduction Systems Implicated in Extra-Intestinal Pathogenic E. coli Infections. Front Cell Infect Microbiol 2017; 7:162. [PMID: 28536675 PMCID: PMC5422438 DOI: 10.3389/fcimb.2017.00162] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 04/18/2017] [Indexed: 11/13/2022] Open
Abstract
Extra-intestinal pathogenic E. coli (ExPEC) infections are common in mammals and birds. The predominant ExPEC types are avian pathogenic E. coli (APEC), neonatal meningitis causing E. coli/meningitis associated E. coli (NMEC/MAEC), and uropathogenic E. coli (UPEC). Many reviews have described current knowledge on ExPEC infection strategies and virulence factors, especially for UPEC. However, surprisingly little has been reported on the regulatory modules that have been identified as critical in ExPEC pathogenesis. Two-component systems (TCSs) comprise the predominant method by which bacteria respond to changing environments and play significant roles in modulating bacterial fitness in diverse niches. Recent studies have highlighted the potential of manipulating signal transduction systems as a means to chemically re-wire bacterial pathogens, thereby reducing selective pressure and avoiding the emergence of antibiotic resistance. This review begins by providing a brief introduction to characterized infection strategies and common virulence factors among APEC, NMEC, and UPEC and continues with a comprehensive overview of two-component signal transduction networks that have been shown to influence ExPEC pathogenesis.
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Affiliation(s)
- Erin J Breland
- Department of Pharmacology, Vanderbilt University Medical CenterNashville, TN, USA
| | - Allison R Eberly
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical CenterNashville, TN, USA
| | - Maria Hadjifrangiskou
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical CenterNashville, TN, USA.,Department of Urology, Vanderbilt University Medical CenterNashville, TN, USA
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43
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Liao C, Liang X, Yang F, Soupir ML, Howe AC, Thompson ML, Jarboe LR. Allelic Variation in Outer Membrane Protein A and Its Influence on Attachment of Escherichia coli to Corn Stover. Front Microbiol 2017; 8:708. [PMID: 28515712 PMCID: PMC5413513 DOI: 10.3389/fmicb.2017.00708] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 04/05/2017] [Indexed: 01/16/2023] Open
Abstract
Understanding the genetic factors that govern microbe-sediment interactions in aquatic environments is important for water quality management and reduction of waterborne disease outbreaks. Although chemical properties of bacteria have been identified that contribute to initiation of attachment, the outer membrane proteins that contribute to these chemical properties still remain unclear. In this study we explored the attachment of 78 Escherichia coli environmental isolates to corn stover, a representative agricultural residue. Outer membrane proteome analysis led to the observation of amino acid variations, some of which had not been previously described, in outer membrane protein A (OmpA) at 10 distinct locations, including each of the four extracellular loops, three of the eight transmembrane segments, the proline-rich linker and the dimerization domain. Some of the polymorphisms within loops 1, 2, and 3 were found to significantly co-occur. Grouping of sequences according to the outer loop polymorphisms revealed five distinct patterns that each occur in at least 5% of our isolates. The two most common patterns, I and II, are encoded by 33.3 and 20.5% of these isolates and differ at each of the four loops. Statistically significant differences in attachment to corn stover were observed among isolates expressing different versions of OmpA and when different versions of OmpA were expressed in the same genetic background. Most notable was the increased corn stover attachment associated with a loop 3 sequence of SNFDGKN relative to the standard SNVYGKN sequence. These results provide further insight into the allelic variation of OmpA and implicate OmpA in contributing to attachment to corn stover.
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Affiliation(s)
- Chunyu Liao
- Interdepartmental Microbiology Program, Iowa State UniversityAmes, IA, USA
| | - Xiao Liang
- Department of Agricultural and Biosystems Engineering, Iowa State UniversityAmes, IA, USA
| | - Fan Yang
- Department of Agricultural and Biosystems Engineering, Iowa State UniversityAmes, IA, USA
| | - Michelle L Soupir
- Interdepartmental Microbiology Program, Iowa State UniversityAmes, IA, USA.,Department of Agricultural and Biosystems Engineering, Iowa State UniversityAmes, IA, USA
| | - Adina C Howe
- Interdepartmental Microbiology Program, Iowa State UniversityAmes, IA, USA.,Department of Agricultural and Biosystems Engineering, Iowa State UniversityAmes, IA, USA
| | | | - Laura R Jarboe
- Interdepartmental Microbiology Program, Iowa State UniversityAmes, IA, USA.,Department of Chemical and Biological Engineering, Iowa State UniversityAmes, IA, USA
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Hejair HMA, Zhu Y, Ma J, Zhang Y, Pan Z, Zhang W, Yao H. Functional role of ompF and ompC porins in pathogenesis of avian pathogenic Escherichia coli. Microb Pathog 2017; 107:29-37. [PMID: 28315387 DOI: 10.1016/j.micpath.2017.02.033] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/21/2017] [Accepted: 02/21/2017] [Indexed: 02/06/2023]
Abstract
Avian pathogenic Escherichia coli is an important pathogen causes systemic infections in avian species and large economic losses in poultry industry worldwide. The functional role of porins during the infection and their mechanisms of interaction with host tissues for adhesion to and invasion are poorly understood. However, whether porins play a role in infection remains unclear. In this study we evaluated the potential of ompF and ompC outer membrane porins in the pathogenesis of avian pathogenic E. coli (APEC) strain TW-XM. The ompF and ompC were deleted to generate a series of mutants. We found that, ΔompF and ΔompC reduced significantly the adherence by 41.3% and 46.1% and invasion capabilities of APEC to mouse brain microvascular endothelial cell (BMEC) bEnd.3 cells in vitro by 51.9% and 49.7% respectively, compared with the wild strain TW-XM. In vivo experiment based on the measurement of the LD50 have also shown that, ΔompF and ΔompC reduced the bacterial virulence by 9.8-fold, 12.3-fold in ducklings and 9-fold, 10.2-fold in mouse models. Animal infection experiments further revealed that, loss of ompF and ompC reduced TW-XM colonization and invasion capacity in brains, lungs and blood compared to wild-type strain TW-XM (P > 0.01). These virulence-related phenotypes were partially recoverable by genetic complementation. The results of the quantitative real-time reverse transcription-PCR (qRT-PCR) indicated that, the loss of ompF and ompC significantly decreased the expression levels of ompA, fimC and iBeA genes in the mutant strains, compared to wild-type strainTW-XM (P < 0.01). Collectively, our data demonstrate that inactivation of these two porins decreased adhesion, invasion, colonization, proliferation capacities, possibly by reduced expression levels of ompA, fimC and iBeA, which may indicate the involvement of ompF and ompC in APEC pathogenesis.
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Affiliation(s)
- Hassan M A Hejair
- College of Veterinary Medicine, Nanjing Agricultural University, Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; College of Veterinary Sciences, University of Nyala, Nyala, Sudan
| | - Yinchu Zhu
- College of Veterinary Medicine, Nanjing Agricultural University, Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
| | - Jiale Ma
- College of Veterinary Medicine, Nanjing Agricultural University, Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
| | - Yue Zhang
- College of Veterinary Medicine, Nanjing Agricultural University, Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
| | - Zihao Pan
- College of Veterinary Medicine, Nanjing Agricultural University, Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
| | - Wei Zhang
- College of Veterinary Medicine, Nanjing Agricultural University, Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
| | - Huochun Yao
- College of Veterinary Medicine, Nanjing Agricultural University, Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China.
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45
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Sato Y, Unno Y, Kawakami S, Ubagai T, Ono Y. Virulence characteristics of Acinetobacter baumannii clinical isolates vary with the expression levels of omps. J Med Microbiol 2017; 66:203-212. [PMID: 27902395 DOI: 10.1099/jmm.0.000394] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
PURPOSE We investigated the expression levels of virulence factors (ompA, omp33-36 and carO) in five clinical isolates and in a standard ATCC 19606 strain of Acinetobacter baumannii to determine their effect on the virulence characteristics of the isolates. METHODOLOGY The mRNA levels of omps and proinflammatory cytokines were analyzed by quantitative real-time PCR. For adherence assay, after human lung epithelial cells (A549) were co-cultured with A. baumannii at 37 °C for 2 h, the cell-adherent bacteria was counted. Pearson correlation analysis was used to compare the omps mRNA levels, the proinflammatory cytokines and the number of adherent bacteria. RESULTS The mRNA levels of ompA in the clinical isolates were higher and similar compared with those in ATCC 19606, whereas the mRNA levels of omp33-36 in the clinical isolates were lower and similar compared with those in ATCC 19606. The mRNA levels of carO in the clinical isolates were significantly higher than those in ATCC 19606. The number of cell-adherent clinical isolates was higher than that of cell-adherent ATCC 19606. Furthermore, the number of cell-adherent clinical isolates was positively and significantly correlated with ompA mRNA level. The mRNA levels of TNF-α, IL-6 and IL-8 in A549 cells co-cultured with the clinical isolates were lower than those in A549 cells co-cultured with ATCC 19606. Moreover, the mRNA levels of TNF-α, IL-6 and IL-8 were negatively and significantly correlated with those of carO in the isolates. CONCLUSION These results provide insights into the renewed virulence characteristics of A. baumannii clinical isolates that depend on cell adherence capacity and the expression level of omp mRNAs.
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Affiliation(s)
- Yoshinori Sato
- Department of Microbiology and Immunology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
| | - Yuka Unno
- Department of Microbiology and Immunology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
| | - Sayoko Kawakami
- Department of Microbiology and Immunology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
| | - Tsuneyuki Ubagai
- Department of Microbiology and Immunology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
| | - Yasuo Ono
- Department of Microbiology and Immunology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
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46
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A journey into the brain: insight into how bacterial pathogens cross blood-brain barriers. Nat Rev Microbiol 2017; 15:149-159. [PMID: 28090076 DOI: 10.1038/nrmicro.2016.178] [Citation(s) in RCA: 164] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The blood-brain barrier, which is one of the tightest barriers in the body, protects the brain from insults, such as infections. Indeed, only a few of the numerous blood-borne bacteria can cross the blood-brain barrier to cause meningitis. In this Review, we focus on invasive extracellular pathogens, such as Neisseria meningitidis, Streptococcus pneumoniae, group B Streptococcus and Escherichia coli, to review the obstacles that bacteria have to overcome in order to invade the meninges from the bloodstream, and the specific skills they have developed to bypass the blood-brain barrier. The medical importance of understanding how these barriers can be circumvented is underlined by the fact that we need to improve drug delivery into the brain.
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47
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Dennehy R, Romano M, Ruggiero A, Mohamed YF, Dignam SL, Mujica Troncoso C, Callaghan M, Valvano MA, Berisio R, McClean S. The Burkholderia cenocepacia peptidoglycan-associated lipoprotein is involved in epithelial cell attachment and elicitation of inflammation. Cell Microbiol 2016; 19. [PMID: 27886433 DOI: 10.1111/cmi.12691] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 10/18/2016] [Accepted: 11/03/2016] [Indexed: 12/26/2022]
Abstract
The Burkholderia cepacia complex (Bcc) is a group of Gram-negative opportunistic pathogens causing infections in people with cystic fibrosis (CF). Bcc is highly antibiotic resistant, making conventional antibiotic treatment problematic. The identification of novel targets for anti-virulence therapies should improve therapeutic options for infected CF patients. We previously identified that the peptidoglycan-associated lipoprotein (Pal) was immunogenic in Bcc infected CF patients; however, its role in Bcc pathogenesis is unknown. The virulence of a pal deletion mutant (Δpal) in Galleria mellonella was 88-fold reduced (p < .001) compared to wild type. The lipopolysaccharide profiles of wild type and Δpal were identical, indicating no involvement of Pal in O-antigen transport. However, Δpal was more susceptible to polymyxin B. Structural elucidation by X-ray crystallography and calorimetry demonstrated that Pal binds peptidoglycan fragments. Δpal showed a 1.5-fold reduced stimulation of IL-8 in CF epithelial cells relative to wild type (p < .001), demonstrating that Pal is a significant driver of inflammation. The Δpal mutant had reduced binding to CFBE41o- cells, but adhesion of Pal-expressing recombinant E. coli to CFBE41o- cells was enhanced compared to wild-type E. coli (p < .0001), confirming that Pal plays a direct role in host cell attachment. Overall, Bcc Pal mediates host cell attachment and stimulation of cytokine secretion, contributing to Bcc pathogenesis.
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Affiliation(s)
- Ruth Dennehy
- Centre of Microbial Host Interactions, Institute of Technology Tallaght, Dublin, Ireland
| | - Maria Romano
- National Research Council, Institute of Biostructures and Bioimaging, Naples, Italy
| | - Alessia Ruggiero
- National Research Council, Institute of Biostructures and Bioimaging, Naples, Italy
| | - Yasmine F Mohamed
- Centre for Experimental Medicine, Queen's University, Belfast, Northern Ireland.,Faculty of Pharmacy, Department of Microbiology, Alexandria University, Alexandria, Egypt
| | - Simon L Dignam
- Centre of Microbial Host Interactions, Institute of Technology Tallaght, Dublin, Ireland
| | | | - Máire Callaghan
- Centre of Microbial Host Interactions, Institute of Technology Tallaght, Dublin, Ireland
| | - Miguel A Valvano
- Centre for Experimental Medicine, Queen's University, Belfast, Northern Ireland
| | - Rita Berisio
- National Research Council, Institute of Biostructures and Bioimaging, Naples, Italy
| | - Siobhán McClean
- Centre of Microbial Host Interactions, Institute of Technology Tallaght, Dublin, Ireland
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Sphingosine 1-Phosphate Activation of EGFR As a Novel Target for Meningitic Escherichia coli Penetration of the Blood-Brain Barrier. PLoS Pathog 2016; 12:e1005926. [PMID: 27711202 PMCID: PMC5053521 DOI: 10.1371/journal.ppat.1005926] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 09/11/2016] [Indexed: 12/24/2022] Open
Abstract
Central nervous system (CNS) infection continues to be an important cause of mortality and morbidity, necessitating new approaches for investigating its pathogenesis, prevention and therapy. Escherichia coli is the most common Gram-negative bacillary organism causing meningitis, which develops following penetration of the blood-brain barrier (BBB). By chemical library screening, we identified epidermal growth factor receptor (EGFR) as a contributor to E. coli invasion of the BBB in vitro. Here, we obtained the direct evidence that CNS-infecting E. coli exploited sphingosine 1-phosphate (S1P) for EGFR activation in penetration of the BBB in vitro and in vivo. We found that S1P was upstream of EGFR and participated in EGFR activation through S1P receptor as well as through S1P-mediated up-regulation of EGFR-related ligand HB-EGF, and blockade of S1P function through targeting sphingosine kinase and S1P receptor inhibited EGFR activation, and also E. coli invasion of the BBB. We further found that both S1P and EGFR activations occurred in response to the same E. coli proteins (OmpA, FimH, NlpI), and that S1P and EGFR promoted E. coli invasion of the BBB by activating the downstream c-Src. These findings indicate that S1P and EGFR represent the novel host targets for meningitic E. coli penetration of the BBB, and counteracting such targets provide a novel approach for controlling E. coli meningitis in the era of increasing resistance to conventional antibiotics.
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49
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Boyer L. Escherichia coli K1 meningitis: Analysis of the effects of CNF1 toxin in newborn mice questions its virulence function. Virulence 2016; 7:754-5. [PMID: 27432618 DOI: 10.1080/21505594.2016.1213478] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Laurent Boyer
- a Université Côte d'Azur, INSERM, C3M , Nice , France.,b INSERM, U1065, Center Méditerranéen de médecine Moléculaire , Nice , France
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Naylor KL, Widziolek M, Hunt S, Conolly M, Hicks M, Stafford P, Potempa J, Murdoch C, Douglas CWI, Stafford GP. Role of OmpA2 surface regions of Porphyromonas gingivalis in host-pathogen interactions with oral epithelial cells. Microbiologyopen 2016; 6. [PMID: 27595778 PMCID: PMC5300881 DOI: 10.1002/mbo3.401] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/03/2016] [Accepted: 08/08/2016] [Indexed: 01/27/2023] Open
Abstract
Outer membrane protein A (OmpA) is a key outer membrane protein found in Gram‐negative bacteria that contributes to several crucial processes in bacterial virulence. In Porphyromonas gingivalis, OmpA is predicted as a heterotrimer of OmpA1 and OmpA2 subunits encoded by adjacent genes. Here we describe the role of OmpA and its individual subunits in the interaction of P. gingivalis with oral cells. Using knockout mutagenesis, we show that OmpA2 plays a significant role in biofilm formation and interaction with human epithelial cells. We used protein structure prediction software to identify extracellular loops of OmpA2, and determined these are involved in interactions with epithelial cells as evidenced by inhibition of adherence and invasion of P. gingivalis by synthetic extracellular loop peptides and the ability of the peptides to mediate interaction of latex beads with human cells. In particular, we observe that OmpA2‐loop 4 plays an important role in the interaction with host cells. These data demonstrate for the first time the important role of P. gingivalis OmpA2 extracellular loops in interaction with epithelial cells, which may help design novel peptide‐based antimicrobial therapies for periodontal disease.
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Affiliation(s)
- Kathryn L Naylor
- School of Clinical Dentistry, University of Sheffield, Sheffield, United Kingdom
| | - Magdalena Widziolek
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Stuart Hunt
- School of Clinical Dentistry, University of Sheffield, Sheffield, United Kingdom
| | - Mary Conolly
- School of Clinical Dentistry, University of Sheffield, Sheffield, United Kingdom
| | - Matthew Hicks
- School of Clinical Dentistry, University of Sheffield, Sheffield, United Kingdom
| | - Prachi Stafford
- Biomolecular Research Centre, Sheffield Hallam University, City Campus, Sheffield, United Kingdom
| | - Jan Potempa
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland.,Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky
| | - Craig Murdoch
- School of Clinical Dentistry, University of Sheffield, Sheffield, United Kingdom
| | - C W Ian Douglas
- School of Clinical Dentistry, University of Sheffield, Sheffield, United Kingdom
| | - Graham P Stafford
- School of Clinical Dentistry, University of Sheffield, Sheffield, United Kingdom
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