101
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The Importance of Porins and β-Lactamase in Outer Membrane Vesicles on the Hydrolysis of β-Lactam Antibiotics. Int J Mol Sci 2020; 21:ijms21082822. [PMID: 32316670 PMCID: PMC7215730 DOI: 10.3390/ijms21082822] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 03/31/2020] [Accepted: 04/16/2020] [Indexed: 12/21/2022] Open
Abstract
Gram-negative bacteria have an outer membrane inhibiting the entry of antibiotics. Porins, found within the outer membrane, are involved in regulating the permeability of β-lactam antibiotics. β-lactamases are enzymes that are able to inactivate the antibacterial properties of β-lactam antibiotics. Interestingly, porins and β-lactamase are found in outer membrane vesicles (OMVs) of β-lactam-resistant Escherichia coli and may be involved in the survival of susceptible strains of E. coli in the presence of antibiotics, through the hydrolysis of the β-lactam antibiotic. In this study, OMVs isolated from β-lactam-resistant E. coli and from mutants, lacking porin or β-lactamase, were evaluated to establish if the porins or β-lactamase in OMVs were involved in the degradation of β-lactam antibiotics. OMVs isolated from E. coli deficient in β-lactamase did not show any degradation ability against β-lactam antibiotics, while OMVs lacking OmpC or OmpF showed significantly lower levels of hydrolyzing activity than OMVs from parent E. coli. These data reveal an important role of OMVs in bacterial defense mechanisms demonstrating that the OmpC and OmpF proteins allow permeation of β-lactam antibiotics into the lumen of OMVs, and antibiotics that enter the OMVs can be degraded by β-lactamase.
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102
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Rueter C, Bielaszewska M. Secretion and Delivery of Intestinal Pathogenic Escherichia coli Virulence Factors via Outer Membrane Vesicles. Front Cell Infect Microbiol 2020; 10:91. [PMID: 32211344 PMCID: PMC7068151 DOI: 10.3389/fcimb.2020.00091] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 02/21/2020] [Indexed: 12/14/2022] Open
Abstract
Outer membrane vesicles (OMVs) are nanoscale proteoliposomes secreted from the cell envelope of all Gram-negative bacteria. Originally considered as an artifact of the cell wall, OMVs are now recognized as a general secretion system, which serves to improve the fitness of bacteria and facilitate bacterial interactions in polymicrobial communities as well as interactions between the microbe and the host. In general, OMVs are released in increased amounts from pathogenic bacteria and have been found to harbor much of the contents of the parental bacterium. They mainly encompass components of the outer membrane and the periplasm including various virulence factors such as toxins, adhesins, and immunomodulatory molecules. Numerous studies have clearly shown that the delivery of toxins and other virulence factors via OMVs essentially influences their interactions with host cells. Here, we review the OMV-mediated intracellular deployment of toxins and other virulence factors with a special focus on intestinal pathogenic Escherichia coli. Especially, OMVs ubiquitously produced and secreted by enterohemorrhagic E. coli (EHEC) appear as a highly advanced mechanism for secretion and simultaneous, coordinated and direct delivery of bacterial virulence factors into host cells. OMV-associated virulence factors are not only stabilized by the association with OMVs, but can also often target previously unknown target structures and perform novel activities. The toxins are released by OMVs in their active forms and are transported via cell sorting processes to their specific cell compartments, where they can develop their detrimental effects. OMVs can be considered as bacterial “long distance weapons” that attack host tissues and help bacterial pathogens to establish the colonization of their biological niche(s), impair host cell function, and modulate the defense of the host. Thus, OMVs contribute significantly to the virulence of the pathogenic bacteria.
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Affiliation(s)
- Christian Rueter
- Center for Molecular Biology of Inflammation (ZMBE), Institute of Infectiology, University of Muenster, Münster, Germany
| | - Martina Bielaszewska
- National Institute of Public Health, Reference Laboratory for E. coli and Shigellae, Prague, Czechia.,Institute for Hygiene, University Hospital of Muenster, University of Muenster, Münster, Germany
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103
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Avalos-Gómez C, Reyes-López M, Ramírez-Rico G, Díaz-Aparicio E, Zenteno E, González-Ruiz C, de la Garza M. Effect of apo-lactoferrin on leukotoxin and outer membrane vesicles of Mannheimia haemolytica A2. Vet Res 2020; 51:36. [PMID: 32138772 PMCID: PMC7059318 DOI: 10.1186/s13567-020-00759-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/17/2020] [Indexed: 01/17/2023] Open
Abstract
Mannheimia haemolytica serotype A2 is the principal cause of pneumonic mannheimiosis in ovine and caprine livestock; this disease is a consequence of immune suppression caused by stress and associated viruses and is responsible for significant economic losses in farm production worldwide. Gram-negative bacteria such as M. haemolytica produce outer membrane (OM)-derived spherical structures named outer membrane vesicles (OMVs) that contain leukotoxin and other biologically active virulence factors. In the present study, the relationship between M. haemolytica A2 and bovine lactoferrin (BLf) was studied. BLf is an 80 kDa glycoprotein that possesses bacteriostatic and bactericidal properties and is part of the mammalian innate immune system. Apo-BLf (iron-free) showed a bactericidal effect against M. haemolytica A2, with an observed minimal inhibitory concentration (MIC) of 16 µM. Sublethal doses (2–8 µM) of apo-BLf increased the release of OMVs, which were quantified by flow cytometry. Apo-BLf modified the normal structure of the OM and OMVs, as observed through transmission electron microscopy. Apo-BLf also induced lipopolysaccharide (LPS) release from bacteria, disrupting OM permeability and functionality, as measured by silver staining and SDS and polymyxin B cell permeability assays. Western blot results showed that apo-BLf increased the secretion of leukotoxin in M. haemolytica A2 culture supernatants, possibly through its iron-chelating activity. In contrast, holo-BLf (with iron) did not have this effect, possibly due to differences in the tertiary structure between these proteins. In summary, apo-BLf affected the levels of several M. haemolytica virulence factors and could be evaluated for use in animals as an adjuvant in the treatment of ovine mannheimiosis.
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Affiliation(s)
- Christian Avalos-Gómez
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México (UNAM), 04510, Coyoacán, CdMx, Mexico.,Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Ave. Instituto Politécnico Nacional 2508, Zacatenco, 07360, CdMx, Mexico
| | - Magda Reyes-López
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Ave. Instituto Politécnico Nacional 2508, Zacatenco, 07360, CdMx, Mexico
| | - Gerardo Ramírez-Rico
- Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México (UNAM), 54714, Cuautitlán Izcalli, Estado de México, Mexico
| | - Efrén Díaz-Aparicio
- Centro Nacional de Investigación Disciplinaria en Salud animal e inocuidad, Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP), 05110, Cuajimalpa, CdMx, Mexico
| | - Edgar Zenteno
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), 04510, Coyoacán, CdMx, Mexico
| | - Cynthia González-Ruiz
- Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México (UNAM), 54714, Cuautitlán Izcalli, Estado de México, Mexico
| | - Mireya de la Garza
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Ave. Instituto Politécnico Nacional 2508, Zacatenco, 07360, CdMx, Mexico.
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104
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Nagakubo T, Nomura N, Toyofuku M. Cracking Open Bacterial Membrane Vesicles. Front Microbiol 2020; 10:3026. [PMID: 32038523 PMCID: PMC6988826 DOI: 10.3389/fmicb.2019.03026] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 12/17/2019] [Indexed: 12/24/2022] Open
Abstract
Membrane vesicles (MVs) are nanoparticles composed of lipid membranes that are produced by both Gram-negative and Gram-positive bacteria. MVs have been assigned diverse biological functions, and they show great potential for applications in various fields. However, the mechanisms underlying their functions and biogenesis are not completely understood. Accumulating evidence shows that MVs are heterogenous, and different types of MVs with different compositions are released from the same species. To understand the origin and function of these MVs, determining the biochemical properties of MVs is important. In this review, we will discuss recent progress in understanding the biochemical composition and properties of MVs.
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Affiliation(s)
- Toshiki Nagakubo
- Department of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Nobuhiko Nomura
- Department of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
- Microbiology Research Center for Sustainability, University of Tsukuba, Tsukuba, Japan
| | - Masanori Toyofuku
- Department of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
- Microbiology Research Center for Sustainability, University of Tsukuba, Tsukuba, Japan
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105
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Abstract
Conjugation, transformation, and transduction constitute the three classical mechanisms involved in horizontal gene transfer (HGT) among prokaryotes. In addition, alternative HGT mechanisms exist in groups of organisms. Among them, the use of DNA-containing membrane vesicles as shuttle elements for HGT has been described for a number of microorganisms, including both thermophiles and mesophiles. Here we describe the methods followed to detect, purify, and analyze these vesicles.
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Affiliation(s)
- Alba Blesa
- Centro de BiologÚa Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain.,Department of Biotechnology, Faculty of Experimental Sciences, Universidad Francisco de Vitoria, Madrid, Spain
| | - José Berenguer
- Centro de BiologÚa Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain.
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106
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107
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Kosgodage US, Matewele P, Awamaria B, Kraev I, Warde P, Mastroianni G, Nunn AV, Guy GW, Bell JD, Inal JM, Lange S. Cannabidiol Is a Novel Modulator of Bacterial Membrane Vesicles. Front Cell Infect Microbiol 2019; 9:324. [PMID: 31552202 PMCID: PMC6747004 DOI: 10.3389/fcimb.2019.00324] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 08/28/2019] [Indexed: 12/11/2022] Open
Abstract
Membrane vesicles (MVs) released from bacteria participate in cell communication and host-pathogen interactions. Roles for MVs in antibiotic resistance are gaining increased attention and in this study we investigated if known anti-bacterial effects of cannabidiol (CBD), a phytocannabinoid from Cannabis sativa, could be in part attributed to effects on bacterial MV profile and MV release. We found that CBD is a strong inhibitor of MV release from Gram-negative bacteria (E. coli VCS257), while inhibitory effect on MV release from Gram-positive bacteria (S. aureus subsp. aureus Rosenbach) was negligible. When used in combination with selected antibiotics, CBD significantly increased the bactericidal action of several antibiotics in the Gram-negative bacteria. In addition, CBD increased antibiotic effects of kanamycin in the Gram-positive bacteria, without affecting MV release. CBD furthermore changed protein profiles of MVs released from E. coli after 1 h CBD treatment. Our findings indicate that CBD may pose as a putative adjuvant agent for tailored co-application with selected antibiotics, depending on bacterial species, to increase antibiotic activity, including via MV inhibition, and help reduce antibiotic resistance.
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Affiliation(s)
- Uchini S. Kosgodage
- Cellular and Molecular Immunology Research Centre, School of Human Sciences, London Metropolitan University, London, United Kingdom
| | - Paul Matewele
- Cellular and Molecular Immunology Research Centre, School of Human Sciences, London Metropolitan University, London, United Kingdom
| | - Brigitte Awamaria
- Cellular and Molecular Immunology Research Centre, School of Human Sciences, London Metropolitan University, London, United Kingdom
| | - Igor Kraev
- School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, United Kingdom
| | - Purva Warde
- Bioscience Research Group, Extracellular Vesicle Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - Giulia Mastroianni
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Alistair V. Nunn
- Research Centre for Optimal Health, School of Life Sciences, University of Westminster, London, United Kingdom
| | | | - Jimmy D. Bell
- Research Centre for Optimal Health, School of Life Sciences, University of Westminster, London, United Kingdom
| | - Jameel M. Inal
- Bioscience Research Group, Extracellular Vesicle Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - Sigrun Lange
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London, United Kingdom
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108
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Grüll MP, Mulligan ME, Lang AS. Small extracellular particles with big potential for horizontal gene transfer: membrane vesicles and gene transfer agents. FEMS Microbiol Lett 2019; 365:5067299. [PMID: 30085064 DOI: 10.1093/femsle/fny192] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 08/04/2018] [Indexed: 12/18/2022] Open
Abstract
Bacteria are known to release different types of particles that serve various purposes such as the processing of metabolites, communication, and the transfer of genetic material. One of the most interesting aspects of the production of such particles is the biogenesis and trafficking of complex particles that can carry DNA, RNA, proteins or toxins into the surrounding environment to aid in bacterial survival or lead to gene transfer. Two important bacterial extracellular complexes are membrane vesicles and gene transfer agents. In this review, we will discuss the production, contents and functions of these two types of particles as related to their abilities to facilitate horizontal gene transfer.
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Affiliation(s)
| | - M E Mulligan
- Biochemistry, Memorial University of Newfoundland, St John's, NL, Canada
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109
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Feitosa-Junior OR, Stefanello E, Zaini PA, Nascimento R, Pierry PM, Dandekar AM, Lindow SE, da Silva AM. Proteomic and Metabolomic Analyses of Xylella fastidiosa OMV-Enriched Fractions Reveal Association with Virulence Factors and Signaling Molecules of the DSF Family. PHYTOPATHOLOGY 2019; 109:1344-1353. [PMID: 30973310 DOI: 10.1094/phyto-03-19-0083-r] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Xylella fastidiosa releases outer membrane vesicles (OMVs) known to play a role in the systemic dissemination of this pathogen. OMVs inhibit bacterial attachment to xylem wall and traffic lipases/esterases that act on the degradation of plant cell wall. Here, we extended the characterization of X. fastidiosa OMVs by identifying proteins and metabolites potentially associated with OMVs produced by Temecula1, a Pierce's disease strain, and by 9a5c and Fb7, two citrus variegated chlorosis strains. These results strengthen that one of the OMVs multiple functions is to carry determinants of virulence, such as lipases/esterases, adhesins, proteases, porins, and a pectin lyase-like protein. For the first time, we show that the two citrus variegated chlorosis strains produce X. fastidiosa diffusible signaling factor 2 (DSF2) and citrus variegated chlorosis-DSF (likewise, Temecula1) and most importantly, that these compounds of the DSF (X. fastidiosa DSF) family are associated with OMV-enriched fractions. Altogether, our findings widen the potential functions of X. fastidiosa OMVs in intercellular signaling and host-pathogen interactions.
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Affiliation(s)
- Oséias R Feitosa-Junior
- 1Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
| | - Eliezer Stefanello
- 1Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
| | - Paulo A Zaini
- 1Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
- 2Department of Plant Sciences, University of California, Davis, CA 95616, U.S.A
| | - Rafael Nascimento
- 1Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
- 3Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, MG 38400-902, Brazil
| | - Paulo M Pierry
- 1Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
| | - Abhaya M Dandekar
- 2Department of Plant Sciences, University of California, Davis, CA 95616, U.S.A
| | - Steven E Lindow
- 4Department Plant and Microbial Biology, University of California, Berkeley, CA 94720, U.S.A
| | - Aline M da Silva
- 1Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
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110
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Intercellular Transfer of Chromosomal Antimicrobial Resistance Genes between Acinetobacter baumannii Strains Mediated by Prophages. Antimicrob Agents Chemother 2019; 63:AAC.00334-19. [PMID: 31138576 DOI: 10.1128/aac.00334-19] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 05/22/2019] [Indexed: 01/01/2023] Open
Abstract
The spread of antimicrobial resistance genes (ARGs) among Gram-negative pathogens, including Acinetobacter baumannii, is primarily mediated by transferable plasmids; however, ARGs are frequently integrated into its chromosome. How ARG gets horizontally incorporated into the chromosome of A. baumannii, and whether it functions as a cause for further spread of ARG, remains unknown. Here, we demonstrated intercellular prophage-mediated transfer of chromosomal ARGs without direct cell-cell interaction in A. baumannii We prepared ARG-harboring extracellular DNA (eDNA) components from the culture supernatant of a multidrug-resistant (MDR) A. baumannii NU-60 strain and exposed an antimicrobial-susceptible (AS) A. baumannii ATCC 17978 strain to the eDNA components. The antimicrobial-resistant (AR) A. baumannii ATCC 17978 derivatives appeared to acquire various ARGs, originating from dispersed loci of the MDR A. baumannii chromosome, along with their surrounding regions, by homologous recombination, with the ARGs including armA (aminoglycoside resistance), bla TEM-1 (β-lactam resistance), tet(B) (tetracycline resistance), and gyrA-81L (nalidixic acid resistance) genes. Notably, the eDNAs conferring antimicrobial resistance were enveloped in specific capsid proteins consisting of phage particles, thereby protecting the eDNAs from detergent and DNase treatments. The phages containing ARGs were likely released into the extracellular space from MDR A. baumannii, thereby transducing ARGs into AS A. baumannii, resulting in the acquisition of AR properties by the recipient. We concluded that the generalized transduction, in which phages were capable of carrying random pieces of A. baumannii genomic DNAs, enabled efficacious intercellular transfer of chromosomal ARGs between A. baumannii strains without direct cell-cell interaction.
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111
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Kosgodage US, Matewele P, Mastroianni G, Kraev I, Brotherton D, Awamaria B, Nicholas AP, Lange S, Inal JM. Peptidylarginine Deiminase Inhibitors Reduce Bacterial Membrane Vesicle Release and Sensitize Bacteria to Antibiotic Treatment. Front Cell Infect Microbiol 2019; 9:227. [PMID: 31316918 PMCID: PMC6610471 DOI: 10.3389/fcimb.2019.00227] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 06/11/2019] [Indexed: 12/25/2022] Open
Abstract
Outer membrane and membrane vesicles (OMV/MV) are released from bacteria and participate in cell communication, biofilm formation and host-pathogen interactions. Peptidylarginine deiminases (PADs) are phylogenetically conserved enzymes that catalyze post-translational deimination/citrullination of proteins, causing structural and functional changes in target proteins. PADs also play major roles in the regulation of eukaryotic extracellular vesicle release. Here we show phylogenetically conserved pathways of PAD-mediated OMV/MV release in bacteria and describe deiminated/citrullinated proteins in E. coli and their derived OMV/MVs. Furthermore, we show that PAD inhibitors can be used to effectively reduce OMV/MV release, both in Gram-negative and Gram-positive bacteria. Importantly, this resulted in enhanced antibiotic sensitivity of both E. coli and S. aureus to a range of antibiotics tested. Our findings reveal novel strategies for applying pharmacological OMV/MV-inhibition to reduce antibiotic resistance.
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Affiliation(s)
- Uchini S. Kosgodage
- Cellular and Molecular Immunology Research Centre, School of Human Sciences, London Metropolitan University, London, United Kingdom
| | - Paul Matewele
- Cellular and Molecular Immunology Research Centre, School of Human Sciences, London Metropolitan University, London, United Kingdom
| | - Giulia Mastroianni
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Igor Kraev
- School of Life, Health and Chemical Sciences, The Open University, London, United Kingdom
| | - Dominik Brotherton
- Bioscience Research Group, Extracellular Vesicle Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - Brigitte Awamaria
- Cellular and Molecular Immunology Research Centre, School of Human Sciences, London Metropolitan University, London, United Kingdom
| | - Anthony P. Nicholas
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Sigrun Lange
- Tissue Architecture and Regeneration Research Group, School of Life Sciences, University of Westminster, London, United Kingdom
| | - Jameel M. Inal
- Bioscience Research Group, Extracellular Vesicle Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
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112
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Gull M, El-Baz S. Introductory Chapter: Preface to Plasmids. Plasmid 2019. [DOI: 10.5772/intechopen.78673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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113
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Comparative genome analysis reveals niche-specific genome expansion in Acinetobacter baumannii strains. PLoS One 2019; 14:e0218204. [PMID: 31194814 PMCID: PMC6563999 DOI: 10.1371/journal.pone.0218204] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/28/2019] [Indexed: 12/11/2022] Open
Abstract
The nosocomial pathogen Acinetobacter baumannii acquired clinical significance due to the rapid development of its multi-drug resistant (MDR) phenotype. A. baumannii strains have the ability to colonize several ecological niches including soil, water, and animals, including humans. They also survive under extremely harsh environmental conditions thriving on rare and recalcitrant carbon compounds. However, the molecular basis behind such extreme adaptability of A. baumannii is unknown. We have therefore determined the complete genome sequence of A. baumannii DS002, which was isolated from agricultural soils, and compared it with 78 complete genome sequences of A. baumannii strains having complete information on the source of their isolation. Interestingly, the genome of A. baumannii DS002 showed high similarity to the genome of A. baumannii SDF isolated from the body louse. The environmental and clinical strains, which do not share a monophyletic origin, showed the existence of a strain-specific unique gene pool that supports niche-specific survival. The strains isolated from infected samples contained a genetic repertoire with a unique gene pool coding for iron acquisition machinery, particularly those required for the biosynthesis of acinetobactin. Interestingly, these strains also contained genes required for biofilm formation. However, such gene sets were either partially or completely missing in the environmental isolates, which instead harbored genes required for alternate carbon catabolism and a TonB-dependent transport system involved in the acquisition of iron via siderophores or xenosiderophores.
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114
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Nadhe SB, Singh R, Wadhwani SA, Chopade BA. Acinetobacter sp. mediated synthesis of AgNPs, its optimization, characterization and synergistic antifungal activity against C. albicans. J Appl Microbiol 2019; 127:445-458. [PMID: 31074075 DOI: 10.1111/jam.14305] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 04/25/2019] [Accepted: 05/06/2019] [Indexed: 12/21/2022]
Abstract
AIMS To synthesize silver nanoparticles (AgNPs) with cell free extract of Acinetobacter sp. and evaluate antifungal activity against planktonic and biofilm of Candida. Also, to study mechanism of antifungal action of AgNPs. METHODS AND RESULT Acinetobacter spp were screened for synthesis of AgNPs. Physio-chemical parameters were optimized to obtained monodispersed nanoparticles. Optimized nanoparticles were characterized using spectroscopic, microscopic and diffraction techniques. Antifungal and biofilm disruption activity of AgNPs (10 ± 5 nm) were investigated against C. albicans. Mechanism of antifungal activity of nanosilver was deduced by growth curve, reactive oxygen species generation, thiol interaction and microscopic analysis. Acinetobacter sp. GWRFH 45 gave maximum synthesis of AgNPs. At optimized condition monodispersed, spherical nanoparticles were obtained which were crystalline with negative surface charge. AgNPs exhibited antifungal activity against planktonic cells and biofilm of Candida. AgNPs showed synergistic effect with amphotericin B as well as fluconazole against biofilm disruption. AgNPs were found to affect growth of Candida, generate reactive oxygen species and disrupt cellular morphology. CONCLUSIONS Cell free extract of A. calcoaceticus GWRFH 45 has ability to synthesize AgNPs. AgNPs alone and in combination with drugs have potential to inhibit C. albicans. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first report of bacteriogenic AgNPs used in combination with antifungal drugs against Candida.
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Affiliation(s)
- S B Nadhe
- Department of Microbiology, Savitribai Phule Pune University, Pune, Maharashtra, India
| | - R Singh
- Department of Biotechnology, SIES College of Arts Science and Commerce, Mumbai, Maharashtra, India
| | - S A Wadhwani
- Department of Microbiology, Savitribai Phule Pune University, Pune, Maharashtra, India
| | - B A Chopade
- Department of Microbiology, Savitribai Phule Pune University, Pune, Maharashtra, India.,Dr. Babasaheb Ambedkar, Marathwada University, Aurangabad, Maharashtra, India
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115
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Tashiro Y, Takaki K, Futamata H. Targeted delivery using membrane vesicles in prokaryotes. Biophys Physicobiol 2019; 16:114-120. [PMID: 31131182 PMCID: PMC6530884 DOI: 10.2142/biophysico.16.0_114] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 03/20/2019] [Indexed: 12/16/2022] Open
Abstract
Membrane vesicles (MVs) are lumen-containing spheres of lipid bilayers secreted by all prokaryotes into the extracellular milieu. They have multifunctional roles in stress response, virulence transfer, biofilm formation, and microbial interactions. Remarkably, MVs contain various components, including lytic enzymes, genetic materials, and hydrophobic signals, at high concentrations and transfer them effectively to the target microbial cells. Therefore, MVs act as carriers for bactericidal effects, horizontal gene transfer, and quorum sensing. Although the purpose of secreted MVs remains unclear, recent reports have provided evidence that MVs selectively interact with microbial cells in order to transfer their content to the target species. Herein, we review microbial interactions using MVs and discuss MV-mediated selective delivery of their content to target microbial cells.
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Affiliation(s)
- Yosuke Tashiro
- Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Hamamatsu, Shizuoka 432-8561, Japan.,Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, Hamamatsu, Shizuoka 432-8561, Japan
| | - Kotaro Takaki
- Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Hamamatsu, Shizuoka 432-8561, Japan
| | - Hiroyuki Futamata
- Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Hamamatsu, Shizuoka 432-8561, Japan.,Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, Hamamatsu, Shizuoka 432-8561, Japan.,Research Institute of Green Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan
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116
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Plasmid Characteristics Modulate the Propensity of Gene Exchange in Bacterial Vesicles. J Bacteriol 2019; 201:JB.00430-18. [PMID: 30670543 DOI: 10.1128/jb.00430-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 12/26/2018] [Indexed: 12/28/2022] Open
Abstract
Horizontal gene transfer is responsible for the exchange of many types of genetic elements, including plasmids. Properties of the exchanged genetic element are known to influence the efficiency of transfer via the mechanisms of conjugation, transduction, and transformation. Recently, an alternative general pathway of horizontal gene transfer has been identified, namely, gene exchange by extracellular vesicles. Although extracellular vesicles have been shown to facilitate the exchange of several types of plasmids, the influence of plasmid characteristics on genetic exchange within vesicles is unclear. Here, a set of different plasmids was constructed to systematically test the impact of plasmid properties, specifically, plasmid copy number, size, and origin of replication, on gene transfer in vesicles. The influence of each property on the production, packaging, and uptake of vesicles containing bacterial plasmids was quantified, revealing how plasmid properties modulate vesicle-mediated horizontal gene transfer. The loading of plasmids into vesicles correlates with the plasmid copy number and is influenced by characteristics that help set the number of plasmids within a cell, including size and origin of replication. Plasmid origin also has a separate impact on both vesicle loading and uptake, demonstrating that the origin of replication is a major determinant of the propensity of specific plasmids to transfer within extracellular vesicles.IMPORTANCE Extracellular vesicle formation and exchange are common within bacterial populations. Vesicles package multiple types of biomolecules, including genetic material. The exchange of extracellular vesicles containing genetic material facilitates interspecies DNA transfer and may be a promiscuous mechanism of horizontal gene transfer. Unlike other mechanisms of horizontal gene transfer, it is unclear whether characteristics of the exchanged DNA impact the likelihood of transfer in vesicles. Here, we systematically examine the influence of plasmid copy number, size, and origin of replication on the loading of DNA into vesicles and the uptake of DNA containing vesicles by recipient cells. These results reveal how each plasmid characteristic impacts gene transfer in vesicles and contribute to a greater understanding of the importance of vesicle-mediated gene exchange in the landscape of horizontal gene transfer.
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117
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PmrC (EptA) and CptA Negatively Affect Outer Membrane Vesicle Production in Citrobacter rodentium. J Bacteriol 2019; 201:JB.00454-18. [PMID: 30670547 PMCID: PMC6416907 DOI: 10.1128/jb.00454-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 01/15/2019] [Indexed: 01/12/2023] Open
Abstract
Although OMVs secreted by Gram-negative bacteria fulfill multiple functions, the molecular mechanism of OMV biogenesis remains ill defined. Our group has previously shown that PmrC (also known as EptA) and CptA maintain OM integrity and provide resistance to iron toxicity and antibiotics in the murine pathogen Citrobacter rodentium. In several enteric bacteria, these proteins modify the lipid A and core regions of lipopolysaccharide with phosphoethanolamine moieties. Here, we show that these proteins also repress OMV production in response to environmental iron in C. rodentium. These data support the emerging understanding that lipopolysaccharide modifications are important regulators of OMV biogenesis in Gram-negative bacteria. Outer membrane vesicles (OMVs) are naturally produced by Gram-negative bacteria by a bulging of the outer membrane (OM) and subsequent release into the environment. By serving as vehicles for various cargos, including proteins, nucleic acids and small metabolites, OMVs are central to interbacterial interactions and both symbiotic and pathogenic host bacterial interactions. However, despite their importance, the mechanism of OMV formation remains unclear. Recent evidence indicates that covalent modifications of lipopolysaccharides (LPS) influence OMV biogenesis. Several enteric bacteria modify LPS with phosphoethanolamine (pEtN) using the iron-regulated PmrC (EptA) and CptA pEtN transferases. In wild-type Citrobacter rodentium, the presence of increasing subtoxic concentrations of iron was found to stimulate OMV production 4- to 9-fold above baseline. C. rodentium uses the two-component system PmrAB to sense and adapt to environmental iron. Compared to the wild type, the C. rodentium ΔpmrAB strain exhibited heightened OMV production at similar iron concentrations. PmrAB regulates transcription of pmrC (also known as eptA) and cptA. OMV production in strains lacking either pmrC (eptA) or cptA was similarly increased in comparison to that of the wild type. Importantly, plasmid complementation of C. rodentium strains with either pmrC (eptA) or cptA resulted in a drastic inhibition of OMV production. Finally, we showed that β-lactamase and CroP, two enzymes found in the C. rodentium periplasm and outer membrane (OM), respectively, are associated with OMVs. These data suggest a novel mechanism by which C. rodentium and possibly other Gram-negative bacteria can negatively affect OMV production through the PmrAB-regulated genes pmrC (eptA) and cptA. IMPORTANCE Although OMVs secreted by Gram-negative bacteria fulfill multiple functions, the molecular mechanism of OMV biogenesis remains ill defined. Our group has previously shown that PmrC (also known as EptA) and CptA maintain OM integrity and provide resistance to iron toxicity and antibiotics in the murine pathogen Citrobacter rodentium. In several enteric bacteria, these proteins modify the lipid A and core regions of lipopolysaccharide with phosphoethanolamine moieties. Here, we show that these proteins also repress OMV production in response to environmental iron in C. rodentium. These data support the emerging understanding that lipopolysaccharide modifications are important regulators of OMV biogenesis in Gram-negative bacteria.
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118
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Turner KB, Dean SN, Walper SA. Bacterial bioreactors: Outer membrane vesicles for enzyme encapsulation. Methods Enzymol 2019; 617:187-216. [PMID: 30784402 DOI: 10.1016/bs.mie.2018.12.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Bacterial membrane vesicles, whether naturally occurring or engineered for enhanced functionality, have significant potential as tools for bioremediation, enzyme catalysis, and the development of therapeutics such as vaccines and adjuvants. In many instances, the vesicles themselves and the naturally occurring proteins are sufficient to lend functionality. Alternatively, additional function can be conveyed to these biological nanoparticles through the directed packaging of peptides and proteins, specifically recombinant enzymes chosen to mediate a specific reaction or facilitate a controlled response. Here we will detail mechanisms for directing the packaging of recombinant proteins and peptides into the nascent membrane vesicles (MVs) of Gram-negative bacteria with a focus on both active and passive packaging using both cellular machinery and engineered molecular systems. Additionally, we detail some of the more common methods for bacterial MVs purification, quantitation, and characterization as these methods are requisite for any subsequent experimentation or processing of MV reagents.
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Affiliation(s)
| | - Scott N Dean
- National Research Council Postdoctoral Fellow, Washington, DC, United States
| | - Scott A Walper
- U.S. Naval Research Laboratory, Washington, DC, United States.
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119
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Fulsundar S, Domingues S, Nielsen KM. Vesicle-Mediated Gene Transfer in Acinetobacter baumannii. Methods Mol Biol 2019; 1946:87-94. [PMID: 30798547 DOI: 10.1007/978-1-4939-9118-1_9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The role of vesicle-mediated gene transfer in Acinetobacter baumannii populations has been investigated in the last decade. Importantly, outer membrane vesicles (OMVs) secreted from A. baumannii cells have proven to be efficient agents of transfer of antimicrobial resistance genes to other bacterial species. However, the measurement of vesicle-mediated transfer depends on many experimental parameters. Here, we describe an experimental method useful to study transfer of DNA via membrane vesicles of A. baumannii in various bacterial populations.
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Affiliation(s)
- Shweta Fulsundar
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, India
| | - Sara Domingues
- Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Kaare Magne Nielsen
- Department of Life Sciences and Health, OsloMet-Oslo Metropolitan University, Oslo, Norway.
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120
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Studies on the mechanism of multidrug resistance of Acinetobacter baumannii by proteomic analysis of the outer membrane vesicles of the bacterium. ACTA ACUST UNITED AC 2018. [DOI: 10.1007/s42485-018-0001-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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121
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Nazarian P, Tran F, Boedicker JQ. Modeling Multispecies Gene Flow Dynamics Reveals the Unique Roles of Different Horizontal Gene Transfer Mechanisms. Front Microbiol 2018; 9:2978. [PMID: 30564220 PMCID: PMC6288448 DOI: 10.3389/fmicb.2018.02978] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 11/19/2018] [Indexed: 12/23/2022] Open
Abstract
Horizontal gene transfer within diverse bacterial populations occurs through multiple mechanisms of exchange. The most established routes of gene transfer, transduction, transformation, and conjugation, have been characterized in detail, revealing the advantages and limitations of each mechanism. More recently, interspecies gene exchange via extracellular vesicles has been reported and characterized, making vesicle-mediated exchange a fourth, general mechanism of gene transfer. Despite an understanding of each individual pathway, how all of these mechanisms act in concert has not been explored. Here we develop a model of gene exchange in a multispecies bacterial community that takes into account the rates and limitations of all four gene transfer mechanisms. Our results reveal unique roles for each gene exchange mechanism, and highlight how multiple pathways working together are required for widespread gene exchange within diverse bacterial populations.
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Affiliation(s)
- Phillip Nazarian
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, United States
| | - Frances Tran
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
| | - James Q Boedicker
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, United States.,Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
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122
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Alikina OV, Glazunova OA, Bykov AA, Kiselev SS, Tutukina MN, Shavkunov KS, Ozoline ON. A cohabiting bacterium alters the spectrum of short RNAs secreted by Escherichia coli. FEMS Microbiol Lett 2018; 365:5146451. [PMID: 30376063 DOI: 10.1093/femsle/fny262] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 10/28/2018] [Indexed: 02/07/2023] Open
Abstract
Recently, it has been found that bacteria secrete short RNAs able to affect gene expression in eukaryotic cells, while certain mammalian microRNAs shape the gut microbiome altering bacterial transcriptome. The involvement of bacterial RNAs in communication with other bacteria is also expected, but has not been documented yet. Here, we compared the fractions of extremely short (12-22 nucleotides) RNAs secreted by Escherichia coli grown in a pure culture and jointly with bacteria of the Paenibacillus genus. Besides fragments of rRNAs and tRNAs, abundant in all samples, secreted oligonucleotides (exoRNAs) predominantly contained GC-rich fragments of messenger and antisense RNAs processed from regions with stable secondary structures. They differed in composition from oligonucleotides of intracellular fraction, where fragments of small regulatory RNAs were prevalent. Both fractions contained RNAs capable of forming complementary duplexes, while for exoRNA samples a higher percentage of 3΄-end modified RNAs and different endonuclease cleavage were detected. The presence of a cohabiting bacterium altered the spectrum of E. coli exoRNAs, indicating a population-dependent control over their composition. Possible mechanisms of this effect are discussed.
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MESH Headings
- Biological Transport
- Escherichia coli/chemistry
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Genome, Bacterial
- Nucleic Acid Conformation
- RNA, Antisense/chemistry
- RNA, Antisense/genetics
- RNA, Antisense/metabolism
- RNA, Bacterial/chemistry
- RNA, Bacterial/genetics
- RNA, Bacterial/metabolism
- RNA, Messenger/chemistry
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Ribosomal/chemistry
- RNA, Ribosomal/genetics
- RNA, Ribosomal/metabolism
- RNA, Transfer/chemistry
- RNA, Transfer/genetics
- RNA, Transfer/metabolism
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Affiliation(s)
- Olga V Alikina
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
| | - Olga A Glazunova
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
- Pushchino Research Center of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
| | - Alexandr A Bykov
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
| | - Sergey S Kiselev
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
| | - Maria N Tutukina
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
- Pushchino Research Center of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
| | - Konstantin S Shavkunov
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
- Pushchino Research Center of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
| | - Olga N Ozoline
- Institute of Cell Biophysics of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
- Pushchino Research Center of Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russian Federation
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123
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Ben-Hur S, Biton M, Regev-Rudzki N. Extracellular Vesicles: A Prevalent Tool for Microbial Gene Delivery? Proteomics 2018; 19:e1800170. [PMID: 30358122 DOI: 10.1002/pmic.201800170] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 10/02/2018] [Indexed: 01/08/2023]
Abstract
Genetic plasticity of prokaryotic microbial communities is largely dependent on the ongoing exchange of genetic determinants by Horizontal Gene Transfer (HGT). HGT events allow beneficial genetic transitions to occur throughout microbial life, thus promoting adaptation to changing environmental conditions. Here, the significance of secreted vesicles in mediating HGT between microorganisms is discussed, while focusing on the benefits gained by vesicle-mediated gene delivery and its occurrence under different environmental cues. The potential use of secreted DNA-harboring vesicles as a mechanism of currently unresolved HGT events in eukaryotic microbes is further discussed.
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Affiliation(s)
- Sharon Ben-Hur
- Faculty of Biochemistry, Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Mirit Biton
- Faculty of Biochemistry, Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Neta Regev-Rudzki
- Faculty of Biochemistry, Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
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124
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Toyofuku M, Nomura N, Eberl L. Types and origins of bacterial membrane vesicles. Nat Rev Microbiol 2018; 17:13-24. [DOI: 10.1038/s41579-018-0112-2] [Citation(s) in RCA: 396] [Impact Index Per Article: 66.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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125
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Enterococcus faecium produces membrane vesicles containing virulence factors and antimicrobial resistance related proteins. J Proteomics 2018; 187:28-38. [DOI: 10.1016/j.jprot.2018.05.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 04/25/2018] [Accepted: 05/29/2018] [Indexed: 11/19/2022]
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126
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Buzás EI, Tóth EÁ, Sódar BW, Szabó-Taylor KÉ. Molecular interactions at the surface of extracellular vesicles. Semin Immunopathol 2018; 40:453-464. [PMID: 29663027 PMCID: PMC6208672 DOI: 10.1007/s00281-018-0682-0] [Citation(s) in RCA: 200] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 03/26/2018] [Indexed: 12/21/2022]
Abstract
Extracellular vesicles such as exosomes, microvesicles, apoptotic bodies, and large oncosomes have been shown to participate in a wide variety of biological processes and are currently under intense investigation in many different fields of biomedicine. One of the key features of extracellular vesicles is that they have relatively large surface compared to their volume. Some extracellular vesicle surface molecules are shared with those of the plasma membrane of the releasing cell, while other molecules are characteristic for extracellular vesicular surfaces. Besides proteins, lipids, glycans, and nucleic acids are also players of extracellular vesicle surface interactions. Being secreted and present in high number in biological samples, collectively extracellular vesicles represent a uniquely large interactive surface area which can establish contacts both with cells and with molecules in the extracellular microenvironment. Here, we provide a brief overview of known components of the extracellular vesicle surface interactome and highlight some already established roles of the extracellular vesicle surface interactions in different biological processes in health and disease.
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Affiliation(s)
- Edit I Buzás
- Department of Genetics, Cell- and Immunobiology, Semmelweis University, Budapest, Hungary.
- MTA-SE Immune-Proteogenomics Research Group, Budapest, Hungary.
| | - Eszter Á Tóth
- Department of Genetics, Cell- and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Barbara W Sódar
- Department of Genetics, Cell- and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Katalin É Szabó-Taylor
- Department of Genetics, Cell- and Immunobiology, Semmelweis University, Budapest, Hungary
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127
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Hall JPJ, Brockhurst MA, Harrison E. Sampling the mobile gene pool: innovation via horizontal gene transfer in bacteria. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0424. [PMID: 29061896 DOI: 10.1098/rstb.2016.0424] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2017] [Indexed: 12/26/2022] Open
Abstract
In biological systems, evolutionary innovations can spread not only from parent to offspring (i.e. vertical transmission), but also 'horizontally' between individuals, who may or may not be related. Nowhere is this more apparent than in bacteria, where novel ecological traits can spread rapidly within and between species through horizontal gene transfer (HGT). This important evolutionary process is predominantly a by-product of the infectious spread of mobile genetic elements (MGEs). We will discuss the ecological conditions that favour the spread of traits by HGT, the evolutionary and social consequences of sharing traits, and how HGT is shaped by inherent conflicts between bacteria and MGEs.This article is part of the themed issue 'Process and pattern in innovations from cells to societies'.
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Affiliation(s)
- James P J Hall
- Department of Animal and Plant Sciences, Alfred Denny Building, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Michael A Brockhurst
- Department of Animal and Plant Sciences, Alfred Denny Building, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Ellie Harrison
- P3 Institute, Department of Animal and Plant Sciences, Arthur Willis Environment Centre, University of Sheffield, 1 Maxfield Avenue, Sheffield S10 1AE, UK
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128
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Yu YJ, Wang XH, Fan GC. Versatile effects of bacterium-released membrane vesicles on mammalian cells and infectious/inflammatory diseases. Acta Pharmacol Sin 2018; 39:514-533. [PMID: 28858295 PMCID: PMC5888691 DOI: 10.1038/aps.2017.82] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 05/10/2017] [Indexed: 01/18/2023] Open
Abstract
Gram-negative bacterium-released outer-membrane vesicles (OMVs) and Gram-positive bacterium-released membrane vesicles (MVs) share significant similarities with mammalian cell-derived MVs (eg, microvesicles and exosomes) in terms of structure and their biological activities. Recent studies have revealed that bacterial OMVs/MVs could (1) interact with immune cells to regulate inflammatory responses, (2) transport virulence factors (eg, enzymes, DNA and small RNAs) to host cells and result in cell injury, (3) enhance barrier function by stimulating the expression of tight junction proteins in intestinal epithelial cells, (4) upregulate the expression of endothelial cell adhesion molecules, and (5) serve as natural nanocarriers for immunogenic antigens, enzyme support and drug delivery. In addition, OMVs/MVs can enter the systemic circulation and induce a variety of immunological and metabolic responses. This review highlights the recent advances in the understanding of OMV/MV biogenesis and their compositional remodeling. In addition, interactions between OMVs/MVs and various types of mammalian cells (ie, immune cells, epithelial cells, and endothelial cells) and their pathological/preventive effects on infectious/inflammatory diseases are summarized. Finally, methods for engineering OMVs/MVs and their therapeutic potential are discussed.
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Affiliation(s)
- You-jiang Yu
- Medical College of Yangzhou Polytechnic College, Yangzhou 225009, China
| | - Xiao-hong Wang
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Guo-Chang Fan
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
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129
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Elhosseiny NM, Attia AS. Acinetobacter: an emerging pathogen with a versatile secretome. Emerg Microbes Infect 2018; 7:33. [PMID: 29559620 PMCID: PMC5861075 DOI: 10.1038/s41426-018-0030-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/08/2017] [Accepted: 01/09/2018] [Indexed: 02/06/2023]
Abstract
Acinetobacter baumannii is a notorious pathogen that has emerged as a healthcare nightmare in recent years because it causes serious infections that are associated with high morbidity and mortality rates. Due to its exceptional ability to acquire resistance to almost all available antibiotics, A. baumannii is currently ranked as the first pathogen on the World Health Organization’s priority list for the development of new antibiotics. The versatile range of effectors secreted by A. baumannii represents a large proportion of the virulence arsenal identified in this bacterium to date. Thus, these factors, together with the secretory machinery responsible for their extrusion into the extracellular milieu, are key targets for novel therapeutics that are greatly needed to combat this deadly pathogen. In this review, we provide a comprehensive, up-to-date overview of the organization and regulatory aspects of the Acinetobacter secretion systems, with a special emphasis on their versatile substrates that could be targeted to fight the deadly infections caused by this elusive pathogen.
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Affiliation(s)
- Noha M Elhosseiny
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt
| | - Ahmed S Attia
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt.
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130
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Askarian F, Lapek JD, Dongre M, Tsai CM, Kumaraswamy M, Kousha A, Valderrama JA, Ludviksen JA, Cavanagh JP, Uchiyama S, Mollnes TE, Gonzalez DJ, Wai SN, Nizet V, Johannessen M. Staphylococcus aureus Membrane-Derived Vesicles Promote Bacterial Virulence and Confer Protective Immunity in Murine Infection Models. Front Microbiol 2018. [PMID: 29515544 PMCID: PMC5826277 DOI: 10.3389/fmicb.2018.00262] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Staphylococcus aureus produces membrane-derived vesicles (MVs), which share functional properties to outer membrane vesicles. Atomic force microscopy revealed that S. aureus-derived MVs are associated with the bacterial surface or released into the surrounding environment depending on bacterial growth conditions. By using a comparative proteomic approach, a total of 131 and 617 proteins were identified in MVs isolated from S. aureus grown in Luria-Bertani and brain-heart infusion broth, respectively. Purified S. aureus MVs derived from the bacteria grown in either media induced comparable levels of cytotoxicity and neutrophil-activation. Administration of exogenous MVs increased the resistance of S. aureus to killing by whole blood or purified human neutrophils ex vivo and increased S. aureus survival in vivo. Finally, immunization of mice with S. aureus-derived MVs induced production of IgM, total IgG, IgG1, IgG2a, and IgG2b resulting in protection against subcutaneous and systemic S. aureus infection. Collectively, our results suggest S. aureus MVs can influence bacterial-host interactions during systemic infections and provide protective immunity in murine models of infection.
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Affiliation(s)
- Fatemeh Askarian
- Research Group of Host Microbe Interactions, Department of Medical Biology, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway.,Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States
| | - John D Lapek
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, United States
| | - Mitesh Dongre
- The Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Chih-Ming Tsai
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States
| | - Monika Kumaraswamy
- Division of Infectious Diseases, Department of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Armin Kousha
- Research Group of Host Microbe Interactions, Department of Medical Biology, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway.,Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States
| | - J Andrés Valderrama
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States
| | | | - Jorunn P Cavanagh
- Department of Pediatrics and Neonatal Medicine, University Hospital of North Norway, University Hospital of North Norway, Tromsø, Norway.,Department of Pediatrics, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Satoshi Uchiyama
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States
| | - Tom E Mollnes
- Research Laboratory, Nordland Hospital, Bodø, Norway.,Faculty of Health Sciences, K. G. Jebsen Thrombosis Research and Expertise Center, UiT - The Arctic University of Norway, Tromsø, Norway.,Department of Immunology, Oslo University Hospital, University of Oslo, Oslo, Norway.,K.G. Jebsen Inflammation Research Centre, University of Oslo, Oslo, Norway.,Center for Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway
| | - David J Gonzalez
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, United States.,Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Sun N Wai
- The Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Victor Nizet
- Division of Host-Microbe Systems and Therapeutics, Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States.,Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Mona Johannessen
- Research Group of Host Microbe Interactions, Department of Medical Biology, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway
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131
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Chatterjee S, Mondal A, Mitra S, Basu S. Acinetobacter baumannii transfers the blaNDM-1 gene via outer membrane vesicles. J Antimicrob Chemother 2018; 72:2201-2207. [PMID: 28505330 DOI: 10.1093/jac/dkx131] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 04/07/2017] [Indexed: 01/05/2023] Open
Abstract
Objectives To investigate the transmission of the gene encoding New Delhi metallo-β-lactamase-1 ( bla NDM-1 ) through outer membrane vesicles (OMVs) released from an Acinetobacter baumannii strain (A_115). Methods Isolation and purification of OMVs by density gradient from a carbapenem-resistant clinical strain of A. baumannii harbouring plasmid-mediated bla NDM-1 and aac(6')-Ib-cr genes was performed. DNA was purified from the OMVs and used for PCR and dot-blot analysis. Vesicles treated with DNase I and proteinase K were used to transform A. baumannii ATCC 19606 and Escherichia coli JM109 strains. MIC values for the transformants were determined, followed by PCR and restriction digestion of plasmids. PFGE was done for A_115 and transformants of ATCC 19606 and JM109. Results The A. baumannii strain (ST 1462) released vesicles (25-100 nm) during in vitro growth at late log phase. PCR and dot-blot analysis confirmed the presence of bla NDM-1 and aac(6')-Ib-cr genes in intravesicular DNA. bla NDM-1 and aac(6')-Ib-cr genes were transferred to both the A. baumannii ATCC 19606 and E. coli JM109 recipient cells. The transformation frequency of the purified OMVs was in the range of 10 -5 -10 -6 and gradually reduced with storage of OMVs. The sizes of the plasmids in the transformants and their restriction digestion patterns were identical to the plasmid in A_115. The transformants showed elevated MIC values of the β-lactam group of antibiotics, which confirmed the presence of a bla NDM-1 -harbouring plasmid. Conclusions This is the first experimental evidence of intra- and inter-species transfer of a plasmid harbouring a bla NDM-1 gene in A. baumannii via OMVs with high transformation frequency.
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Affiliation(s)
- Somdatta Chatterjee
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, P33, CIT Road, Scheme XM, Beliaghata, Kolkata 700010, India
| | - Ayan Mondal
- Division of Pathophysiology, National Institute of Cholera and Enteric Diseases, P33, CIT Road, Scheme XM, Beliaghata, Kolkata 700010, India
| | - Shravani Mitra
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, P33, CIT Road, Scheme XM, Beliaghata, Kolkata 700010, India
| | - Sulagna Basu
- Division of Bacteriology, National Institute of Cholera and Enteric Diseases, P33, CIT Road, Scheme XM, Beliaghata, Kolkata 700010, India
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132
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Ambur OH, Engelstädter J, Johnsen PJ, Miller EL, Rozen DE. Steady at the wheel: conservative sex and the benefits of bacterial transformation. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0528. [PMID: 27619692 PMCID: PMC5031613 DOI: 10.1098/rstb.2015.0528] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2016] [Indexed: 12/25/2022] Open
Abstract
Many bacteria are highly sexual, but the reasons for their promiscuity remain obscure. Did bacterial sex evolve to maximize diversity and facilitate adaptation in a changing world, or does it instead help to retain the bacterial functions that work right now? In other words, is bacterial sex innovative or conservative? Our aim in this review is to integrate experimental, bioinformatic and theoretical studies to critically evaluate these alternatives, with a main focus on natural genetic transformation, the bacterial equivalent of eukaryotic sexual reproduction. First, we provide a general overview of several hypotheses that have been put forward to explain the evolution of transformation. Next, we synthesize a large body of evidence highlighting the numerous passive and active barriers to transformation that have evolved to protect bacteria from foreign DNA, thereby increasing the likelihood that transformation takes place among clonemates. Our critical review of the existing literature provides support for the view that bacterial transformation is maintained as a means of genomic conservation that provides direct benefits to both individual bacterial cells and to transformable bacterial populations. We examine the generality of this view across bacteria and contrast this explanation with the different evolutionary roles proposed to maintain sex in eukaryotes. This article is part of the themed issue 'Weird sex: the underappreciated diversity of sexual reproduction'.
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Affiliation(s)
- Ole Herman Ambur
- Department of Life Sciences and Health, Oslo and Akershus University College of Applied Sciences, 1478 Oslo, Norway
| | - Jan Engelstädter
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Pål J Johnsen
- Faculty of Health Sciences, Department of Pharmacy, UiT-The Arctic University of Norway, 9037 Tromsø, Norway
| | - Eric L Miller
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PL, UK
| | - Daniel E Rozen
- Institute of Biology, Leiden University, 2333 BE Leiden, The Netherlands
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133
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Liu Y, Alexeeva S, Defourny KA, Smid EJ, Abee T. Tiny but mighty: bacterial membrane vesicles in food biotechnological applications. Curr Opin Biotechnol 2017; 49:179-184. [PMID: 28985542 DOI: 10.1016/j.copbio.2017.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 08/15/2017] [Accepted: 09/03/2017] [Indexed: 12/15/2022]
Abstract
Membrane vesicle (MV) production is observed in all domains of life. Evidence of MV production accumulated in recent years among bacterial species involved in fermentation processes. These studies revealed MV composition, biological functions and properties, which made us recognize the potential of MVs in food applications as delivery vehicles of various compounds to other bacteria or the human host. Moreover, MV producing strains can deliver benefits as probiotics or starters in fermentation processes. Next to the natural production of MVs, we also highlight possible methods for artificial generation of bacterial MVs and cargo loading to enhance their applicability. We believe that a more in-depth understanding of bacterial MVs opens new avenues for their exploitation in biotechnological applications.
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Affiliation(s)
- Yue Liu
- Wageningen University, Laboratory of Food Microbiology, P.O. Box 17, 6700 AA Wageningen, The Netherlands
| | - Svetlana Alexeeva
- Wageningen University, Laboratory of Food Microbiology, P.O. Box 17, 6700 AA Wageningen, The Netherlands
| | - Kyra Ay Defourny
- Wageningen University, Laboratory of Food Microbiology, P.O. Box 17, 6700 AA Wageningen, The Netherlands
| | - Eddy J Smid
- Wageningen University, Laboratory of Food Microbiology, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
| | - Tjakko Abee
- Wageningen University, Laboratory of Food Microbiology, P.O. Box 17, 6700 AA Wageningen, The Netherlands
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134
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Abstract
Bacterial membrane vesicles (BMVs) are closed spherical nanostructures that are shed naturally and ubiquitously by most bacterial species both in vivo and in vitro. Researchers have elucidated their roles in long-distance transport of a wide array of cargoes, such as proteins, toxins, antigens, virulence factors, microbicidal agents and antibiotics. Given that these natural carriers are important players in intercellular communication, it has been hypothesized that they are equally well attuned for transport and delivery of exogenous therapeutic cargoes. Additionally, BMVs appear to possess specific properties that enable their utilization as drug delivery vehicles. These include their ability to evade the host immune system, protection of the therapeutic payload and natural stability. Using bioengineering approaches, BMVs have been applied as carriers of therapeutic moieties in vaccines and for targeted delivery in cancer. In this article, we explore BMVs from the perspective of understanding their applicability to drug delivery. BMV biology, including biogenesis, physiology and pathology, is briefly reviewed. Practical issues related to bioprocessing, loading of therapeutic moieties and characterization for enabling scalability and commercial viability are evaluated. Finally, challenges to clinical translation and rational design approaches for novel BMV formulations are presented. Although the realization of the full potential of BMVs in drug delivery hinges on the development of scalable approaches for their production as well as the refinement of targeting and loading methods, they are promising candidates for development of a novel generation of drug delivery vehicles in future.
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Affiliation(s)
- Sapna Jain
- Implants, Devices and Drug Delivery Systems Laboratory, Centre for Biodesign and Diagnostics, Translational Health Science and Technology Institute, Faridabad, Haryana, India
| | - Jonathan Pillai
- Implants, Devices and Drug Delivery Systems Laboratory, Centre for Biodesign and Diagnostics, Translational Health Science and Technology Institute, Faridabad, Haryana, India
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135
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Tran F, Boedicker JQ. Genetic cargo and bacterial species set the rate of vesicle-mediated horizontal gene transfer. Sci Rep 2017; 7:8813. [PMID: 28821711 PMCID: PMC5562762 DOI: 10.1038/s41598-017-07447-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/27/2017] [Indexed: 12/22/2022] Open
Abstract
Most bacteria release extracellular vesicles (EVs). Recent studies have found these vesicles are capable of gene delivery, however the consequences of vesicle-mediated transfer on the patterns and rates of gene flow within microbial communities remains unclear. Previous studies have not determined the impact of both the genetic cargo and the donor and recipient species on the rate of vesicle-mediated gene exchange. This report examines the potential for EVs as a mechanism of gene transfer within heterogeneous microbial populations. EVs were harvested from three species of Gram-negative microbes carrying different plasmids. The dynamics of gene transfer into recipient species was measured. This study demonstrates that vesicles enable gene exchange between five species of Gram-negative bacteria, and that the identity of the genetic cargo, donor strain, and recipient strain all influence gene transfer rates. Each species released and acquired vesicles containing genetic material to a variable degree, and the transfer rate did not correlate with the relatedness of the donor and recipient species. The results suggest that EVs may be a general mechanism to exchange non-specialized genetic cargo between bacterial species.
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Affiliation(s)
- Frances Tran
- University of Southern California, Department of Biological Sciences, Seaver Science Center (SSC) 212, 920 Bloom Walk, Los Angeles, CA, 90089, USA
| | - James Q Boedicker
- University of Southern California, Department of Biological Sciences, Seaver Science Center (SSC) 212, 920 Bloom Walk, Los Angeles, CA, 90089, USA.
- University of Southern California, Department of Physics and Astronomy, Seaver Science Center (SSC) 212, 920 Bloom Walk, Los Angeles, CA, 90089, USA.
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136
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Antibiotic-induced release of small extracellular vesicles (exosomes) with surface-associated DNA. Sci Rep 2017; 7:8202. [PMID: 28811610 PMCID: PMC5557920 DOI: 10.1038/s41598-017-08392-1] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 07/10/2017] [Indexed: 02/08/2023] Open
Abstract
Recently, biological roles of extracellular vesicles (which include among others exosomes, microvesicles and apoptotic bodies) have attracted substantial attention in various fields of biomedicine. Here we investigated the impact of sustained exposure of cells to the fluoroquinolone antibiotic ciprofloxacin on the released extracellular vesicles. Ciprofloxacin is widely used in humans against bacterial infections as well as in cell cultures against Mycoplasma contamination. However, ciprofloxacin is an inducer of oxidative stress and mitochondrial dysfunction of mammalian cells. Unexpectedly, here we found that ciprofloxacin induced the release of both DNA (mitochondrial and chromosomal sequences) and DNA-binding proteins on the exofacial surfaces of small extracellular vesicles referred to in this paper as exosomes. Furthermore, a label-free optical biosensor analysis revealed DNA-dependent binding of exosomes to fibronectin. DNA release on the surface of exosomes was not affected any further by cellular activation or apoptosis induction. Our results reveal for the first time that prolonged low-dose ciprofloxacin exposure leads to the release of DNA associated with the external surface of exosomes.
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137
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An evolutionary perspective on plasmid lifestyle modes. Curr Opin Microbiol 2017; 38:74-80. [DOI: 10.1016/j.mib.2017.05.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 05/03/2017] [Accepted: 05/04/2017] [Indexed: 11/19/2022]
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138
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Bacterial membrane vesicles transport their DNA cargo into host cells. Sci Rep 2017; 7:7072. [PMID: 28765539 PMCID: PMC5539193 DOI: 10.1038/s41598-017-07288-4] [Citation(s) in RCA: 201] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 06/27/2017] [Indexed: 12/25/2022] Open
Abstract
Bacterial outer membrane vesicles (OMVs) are extracellular sacs containing biologically active products, such as proteins, cell wall components and toxins. OMVs are reported to contain DNA, however, little is known about the nature of this DNA, nor whether it can be transported into host cells. Our work demonstrates that chromosomal DNA is packaged into OMVs shed by bacteria during exponential phase. Most of this DNA was present on the external surfaces of OMVs, with smaller amounts located internally. The DNA within the internal compartments of Pseudomonas aeruginosa OMVs were consistently enriched in specific regions of the bacterial chromosome, encoding proteins involved in virulence, stress response, antibiotic resistance and metabolism. Furthermore, we demonstrated that OMVs carry DNA into eukaryotic cells, and this DNA was detectable by PCR in the nuclear fraction of cells. These findings suggest a role for OMV-associated DNA in bacterial-host cell interactions and have implications for OMV-based vaccines.
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139
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Membrane vesicles and horizontal gene transfer in prokaryotes. Curr Opin Microbiol 2017; 38:16-21. [DOI: 10.1016/j.mib.2017.03.012] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/15/2017] [Accepted: 03/28/2017] [Indexed: 11/17/2022]
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140
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Pathogen-derived extracellular vesicles coordinate social behaviour and host manipulation. Semin Cell Dev Biol 2017; 67:83-90. [DOI: 10.1016/j.semcdb.2017.03.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 03/17/2017] [Accepted: 03/28/2017] [Indexed: 12/21/2022]
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141
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Abstract
Outer Membrane Vesicles (OMVs) of Gram-negative bacteria are spherical membrane-enclosed entities of endocytic origin. Reported in the consortia of different bacterial species, production of OMVs into extracellular milieu seems essential for their survival. Enriched with bioactive proteins, toxins, and virulence factors, OMVs play a critical role in the bacteria-bacteria and bacteria-host interactions. Emergence of OMVs as distinct cellular entities helps bacteria in adaptating to diverse niches, in competing with other bacteria to protect members of producer species and more importantly play a crucial role in host-pathogen interaction. Composition of OMV, their ability to modulate host immune response, along with coordinated secretion of bacterial effector proteins, endows them with the armory, which can withstand hostile environments. Study of the OMV production under natural and diverse stress conditions has broadened the horizons, and also opened new frontiers in delineating the molecular machinery involved in disease pathogenesis. Playing diverse biological and pathophysiological functions, OMVs hold a great promise in enabling resurgence of bacterial diseases, in concomitance with the steep decline in the efficiency of antibiotics. Having multifaceted role, their emergence as a causative agent for a series of infectious diseases increases the probability for their exploitation in the development of effective diagnostic tools and as vaccines against diverse pathogenic species of Gram-negative origin.
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Affiliation(s)
- Arif Tasleem Jan
- Department of Medical Biotechnology, Yeungnam UniversityGyeongsan, South Korea
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142
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Orench-Rivera N, Kuehn MJ. Environmentally controlled bacterial vesicle-mediated export. Cell Microbiol 2017; 18:1525-1536. [PMID: 27673272 DOI: 10.1111/cmi.12676] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 09/15/2016] [Accepted: 09/21/2016] [Indexed: 01/01/2023]
Abstract
Over the past two decades, researchers studying both microbial and host cell communities have gained an appreciation for the ability of bacteria to produce, regulate, and functionally utilize outer membrane vesicles (OMVs) as a means to survive and interact with their cellular and acellular environments. Common ground has emerged, as it appears that vesicle production is an environmentally controlled and specific secretion process; however, it has been challenging to discover the principles that govern fundamentals of vesicle-mediated transport. Namely, there does not appear to be a single mechanism modulating OMV export, nor universal "markers" for OMV cargo incorporation, nor particular host cell responses common to treatment with all OMVs. Given the diversity of species studied, their differences in envelope architecture and composition, the diversity of environmentally regulated bacterial processes, and the variety of interactions between bacteria and their abiotic and biotic environments, this is hardly surprising. Nevertheless, the ability of bacteria to control exported material in the context of a packaged insoluble particle, a vesicle, is emerging as a significant contribution to bacterial viability, biofilm communities, and bacterial-host interactions. In this review, we focus on detailing important, recent findings regarding the content and functional differences in bacterially secreted vesicles that are influenced by growth conditions.
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Affiliation(s)
- Nichole Orench-Rivera
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina, 27710, USA
| | - Meta J Kuehn
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina, 27710, USA.
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143
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Tashiro Y, Hasegawa Y, Shintani M, Takaki K, Ohkuma M, Kimbara K, Futamata H. Interaction of Bacterial Membrane Vesicles with Specific Species and Their Potential for Delivery to Target Cells. Front Microbiol 2017; 8:571. [PMID: 28439261 PMCID: PMC5383704 DOI: 10.3389/fmicb.2017.00571] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 03/20/2017] [Indexed: 12/01/2022] Open
Abstract
Membrane vesicles (MVs) are secreted from a wide range of microbial species and transfer their content to other cells. Although MVs play critical roles in bacterial communication, whether MVs selectively interact with bacterial cells in microbial communities is unclear. In this study, we investigated the specificity of the MV-cell interactions and evaluated the potential of MVs to target bacterial cells for delivery. MV association with bacterial cells was examined using a fluorescent membrane dye to label MVs. MVs derived from the enterobacterium Buttiauxella agrestis specifically interacted with cells of the parent strain but interacted less specifically with those of other genera tested in this study. Electron microscopic analyses showed that MVs were not only attached on B. agrestis cells but also fused to them. The interaction energy, which was characterized by hydrodynamic diameter and zeta potential based on the Derjaguin–Landau–Verwey–Overbeek (DLVO) theory, was significant low between MVs and cells in B. agrestis, compared to those between B. agrestis MVs and cells of other genera. Similar specific interaction was also occurred between B. agrestis MVs and cells of six other species belonging to Buttiauxella spp. B. agrestis harboring plasmid pBBR1MCS-1 secreted plasmid-containing MVs (p-MVs), and plasmid DNA in p-MVs was transferred to the same species. Moreover, antibiotic-associated MVs enabled effective killing of target species; the survival rate of B. agrestis was lower than those of Escherichia coli and Pseudomonas aeruginosa in the presence of gentamicin-associated MVs derived from B. agrestis. Altogether, we provide the evidence that MVs selectively interact with target bacterial cells and offer a new avenue for controlling specific bacterial species using bacterial MVs in microbial communities.
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Affiliation(s)
- Yosuke Tashiro
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka UniversityHamamatsu, Japan
| | - Yusuke Hasegawa
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka UniversityHamamatsu, Japan
| | - Masaki Shintani
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka UniversityHamamatsu, Japan.,Graduate School of Science and Technology, Shizuoka UniversityHamamatsu, Japan.,Japan Collection of Microorganisms, RIKEN BioResource CenterTsukuba, Japan
| | - Kotaro Takaki
- Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, Shizuoka UniversityHamamatsu, Japan
| | - Moriya Ohkuma
- Japan Collection of Microorganisms, RIKEN BioResource CenterTsukuba, Japan
| | - Kazuhide Kimbara
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka UniversityHamamatsu, Japan.,Graduate School of Science and Technology, Shizuoka UniversityHamamatsu, Japan
| | - Hiroyuki Futamata
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka UniversityHamamatsu, Japan.,Graduate School of Science and Technology, Shizuoka UniversityHamamatsu, Japan.,Research Institute of Green Science and Technology, Shizuoka UniversityShizuoka, Japan
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144
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Weber BS, Kinsella RL, Harding CM, Feldman MF. The Secrets of Acinetobacter Secretion. Trends Microbiol 2017; 25:532-545. [PMID: 28216293 DOI: 10.1016/j.tim.2017.01.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 01/10/2017] [Accepted: 01/20/2017] [Indexed: 12/23/2022]
Abstract
Infections caused by the bacterial pathogen Acinetobacter baumannii are a mounting concern for healthcare practitioners as widespread antibiotic resistance continues to limit therapeutic treatment options. The biological processes used by A. baumannii to cause disease are not well defined, but recent research has indicated that secreted proteins may play a major role. A variety of mechanisms have now been shown to contribute to protein secretion by A. baumannii and other pathogenic species of Acinetobacter, including a type II secretion system (T2SS), a type VI secretion system (T6SS), autotransporter, and outer membrane vesicles (OMVs). In this review, we summarize the current knowledge of secretion systems in Acinetobacter species, and highlight their unique aspects that contribute to the pathogenicity and persistence of these emerging pathogens.
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Affiliation(s)
- Brent S Weber
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO, USA; Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Rachel L Kinsella
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO, USA; Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Christian M Harding
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO, USA
| | - Mario F Feldman
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO, USA.
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145
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A Two-Component Regulatory System Impacts Extracellular Membrane-Derived Vesicle Production in Group A Streptococcus. mBio 2016; 7:mBio.00207-16. [PMID: 27803183 PMCID: PMC5090034 DOI: 10.1128/mbio.00207-16] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Export of macromolecules via extracellular membrane-derived vesicles (MVs) plays an important role in the biology of Gram-negative bacteria. Gram-positive bacteria have also recently been reported to produce MVs; however, the composition and mechanisms governing vesiculogenesis in Gram-positive bacteria remain undefined. Here, we describe MV production in the Gram-positive human pathogen group A streptococcus (GAS), the etiological agent of necrotizing fasciitis and streptococcal toxic shock syndrome. M1 serotype GAS isolates in culture exhibit MV structures both on the cell wall surface and in the near vicinity of bacterial cells. A comprehensive analysis of MV proteins identified both virulence-associated protein substrates of the general secretory pathway in addition to "anchorless surface proteins." Characteristic differences in the contents, distributions, and fatty acid compositions of specific lipids between MVs and GAS cell membrane were also observed. Furthermore, deep RNA sequencing of vesicular RNAs revealed that GAS MVs contained differentially abundant RNA species relative to bacterial cellular RNA. MV production by GAS strains varied in a manner dependent on an intact two-component system, CovRS, with MV production negatively regulated by the system. Modulation of MV production through CovRS was found to be independent of both GAS cysteine protease SpeB and capsule biosynthesis. Our data provide an explanation for GAS secretion of macromolecules, including RNAs, lipids, and proteins, and illustrate a regulatory mechanism coordinating this secretory response. IMPORTANCE Group A streptococcus (GAS) is a Gram-positive bacterial pathogen responsible for more than 500,000 deaths annually. Establishment of GAS infection is dependent on a suite of proteins exported via the general secretory pathway. Here, we show that GAS naturally produces extracellular vesicles with a unique lipid composition that are laden with proteins and RNAs. Interestingly, both virulence-associated proteins and RNA species were found to be differentially abundant in vesicles relative to the bacteria. Furthermore, we show that genetic disruption of the virulence-associated two-component regulator CovRS leads to an increase in vesicle production. This study comprehensively describes the protein, RNA, and lipid composition of GAS-secreted MVs and alludes to a regulatory system impacting this process.
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146
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Tandberg JI, Lagos LX, Langlete P, Berger E, Rishovd AL, Roos N, Varkey D, Paulsen IT, Winther-Larsen HC. Comparative Analysis of Membrane Vesicles from Three Piscirickettsia salmonis Isolates Reveals Differences in Vesicle Characteristics. PLoS One 2016; 11:e0165099. [PMID: 27764198 PMCID: PMC5072724 DOI: 10.1371/journal.pone.0165099] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 10/06/2016] [Indexed: 01/18/2023] Open
Abstract
Membrane vesicles (MVs) are spherical particles naturally released from the membrane of Gram-negative bacteria. Bacterial MV production is associated with a range of phenotypes including biofilm formation, horizontal gene transfer, toxin delivery, modulation of host immune responses and virulence. This study reports comparative profiling of MVs from bacterial strains isolated from three widely disperse geographical areas. Mass spectrometry identified 119, 159 and 142 proteins in MVs from three different strains of Piscirickettsia salmonis isolated from salmonids in Chile (LF-89), Norway (NVI 5692) and Canada (NVI 5892), respectively. MV comparison revealed several strain-specific differences related to higher virulence capability for LF-89 MVs, both in vivo and in vitro, and stronger similarities between the NVI 5692 and NVI 5892 MV proteome. The MVs were similar in size and appearance as analyzed by electron microscopy and dynamic light scattering. The MVs from all three strains were internalized by both commercial and primary immune cell cultures, which suggest a potential role of the MVs in the bacterium’s utilization of leukocytes. When MVs were injected into an adult zebrafish infection model, an upregulation of several pro-inflammatory genes were observed in spleen and kidney, indicating a modulating effect on the immune system. The present study is the first comparative analysis of P. salmonis derived MVs, highlighting strain-specific vesicle characteristics. The results further illustrate that the MV proteome from one bacterial strain is not representative of all bacterial strains within one species.
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Affiliation(s)
- Julia I. Tandberg
- Center of Integrative Microbiology and Evolution, University of Oslo, Oslo, Norway
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, Oslo, Norway
| | - Leidy X. Lagos
- Center of Integrative Microbiology and Evolution, University of Oslo, Oslo, Norway
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, Oslo, Norway
| | - Petter Langlete
- Center of Integrative Microbiology and Evolution, University of Oslo, Oslo, Norway
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, Oslo, Norway
| | - Eva Berger
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, Oslo, Norway
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Anne-Lise Rishovd
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, Oslo, Norway
| | - Norbert Roos
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Deepa Varkey
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Ian T. Paulsen
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Hanne C. Winther-Larsen
- Center of Integrative Microbiology and Evolution, University of Oslo, Oslo, Norway
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, Oslo, Norway
- * E-mail:
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147
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Insights on the Horizontal Gene Transfer of Carbapenemase Determinants in the Opportunistic Pathogen Acinetobacter baumannii. Microorganisms 2016; 4:microorganisms4030029. [PMID: 27681923 PMCID: PMC5039589 DOI: 10.3390/microorganisms4030029] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/21/2016] [Accepted: 08/09/2016] [Indexed: 12/23/2022] Open
Abstract
Horizontal gene transfer (HGT) is a driving force to the evolution of bacteria. The fast emergence of antimicrobial resistance reflects the ability of genetic adaptation of pathogens. Acinetobacter baumannii has emerged in the last few decades as an important opportunistic nosocomial pathogen, in part due to its high capacity of acquiring resistance to diverse antibiotic families, including to the so-called last line drugs such as carbapenems. The rampant selective pressure and genetic exchange of resistance genes hinder the effective treatment of resistant infections. A. baumannii uses all the resistance mechanisms to survive against carbapenems but production of carbapenemases are the major mechanism, which may act in synergy with others. A. baumannii appears to use all the mechanisms of gene dissemination. Beyond conjugation, the mostly reported recent studies point to natural transformation, transduction and outer membrane vesicles-mediated transfer as mechanisms that may play a role in carbapenemase determinants spread. Understanding the genetic mobilization of carbapenemase genes is paramount in preventing their dissemination. Here we review the carbapenemases found in A. baumannii and present an overview of the current knowledge of contributions of the various HGT mechanisms to the molecular epidemiology of carbapenem resistance in this relevant opportunistic pathogen.
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Li J, Azam F, Zhang S. Outer membrane vesicles containing signalling molecules and active hydrolytic enzymes released by a coral pathogenVibrio shiloniiAK1. Environ Microbiol 2016; 18:3850-3866. [DOI: 10.1111/1462-2920.13344] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 04/14/2016] [Indexed: 01/09/2023]
Affiliation(s)
- Jie Li
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences; Guangzhou Guangdong P. R. China
| | - Farooq Azam
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego; La Jolla CA USA
| | - Si Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences; Guangzhou Guangdong P. R. China
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149
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Characterization and Vaccine Potential of Outer Membrane Vesicles Produced by Haemophilus parasuis. PLoS One 2016; 11:e0149132. [PMID: 26930282 PMCID: PMC4773134 DOI: 10.1371/journal.pone.0149132] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/26/2016] [Indexed: 11/19/2022] Open
Abstract
Haemophilus parasuis is a Gram-negative bacterium that colonizes the upper respiratory tract of swine and is capable of causing a systemic infection, resulting in high morbidity and mortality. H. parasuis isolates display a wide range of virulence and virulence factors are largely unknown. Commercial bacterins are often used to vaccinate swine against H. parasuis, though strain variability and lack of cross-reactivity can make this an ineffective means of protection. Outer membrane vesicles (OMV) are spherical structures naturally released from the membrane of bacteria and OMV are often enriched in toxins, signaling molecules and other bacterial components. Examination of OMV structures has led to identification of virulence factors in a number of bacteria and they have been successfully used as subunit vaccines. We have isolated OMV from both virulent and avirulent strains of H. parasuis, have examined their protein content and assessed their ability to induce an immune response in the host. Vaccination with purified OMV derived from the virulent H. parasuis Nagasaki strain provided protection against challenge with a lethal dose of the bacteria.
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Abstract
The genus Acinetobacter encompasses multiple nosocomial opportunistic pathogens that are of increasing worldwide relevance because of their ability to survive exposure to various antimicrobial and sterilization agents. Among these, Acinetobacter baumannii, Acinetobacter nosocomialis, and Acinetobacter pittii are the most frequently isolated in hospitals around the world. Despite the growing incidence of multidrug-resistant Acinetobacter spp., little is known about the factors that contribute to pathogenesis. New strategies for treating and managing infections caused by multidrug-resistant Acinetobacter strains are urgently needed, and this requires a detailed understanding of the pathobiology of these organisms. In recent years, some virulence factors important for Acinetobacter colonization have started to emerge. In this review, we focus on several recently described virulence factors that act at the bacterial surface level, such as the capsule, O-linked protein glycosylation, and adhesins. Furthermore, we describe the current knowledge regarding the type II and type VI secretion systems present in these strains.
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