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Outer membrane vesicle

Laura E Yates, Dominic C Mills, Matthew P DeLisa
Bacteria have garnered increased interest in recent years as a platform for the biosynthesis of a variety of glycomolecules such as soluble oligosaccharides, surface-exposed carbohydrates, and glycoproteins. The ability to engineer commonly used laboratory species such as Escherichia coli to efficiently synthesize non-native sugar structures by recombinant expression of enzymes from various carbohydrate biosynthesis pathways has allowed for the facile generation of important products such as conjugate vaccines, glycosylated outer membrane vesicles, and a variety of other research reagents for studying and understanding the role of glycans in living systems...
August 12, 2018: Advances in Biochemical Engineering/biotechnology
Paul R Meers, Carol Liu, Rensa Chen, William Bartos, Julianne Davis, Nicole Dziedzic, Jason Orciuolo, Szymon Kutyla, Maria Jose Pozo, Deepti Mithrananda, Dominick Panzera, Shu Wang
Lysobacter enzymogenes C3 is a predatory strain of gram-negative gliding bacteria that produces antifungal antibiotics by the polyketide synthetic pathway. Outer membrane vesicles (OMV) are formed as a stress response and can deliver virulence factors to host cells. The production of OMV by C3 and their role in antifungal activity are reported here. Vesicles in the range of 130-150 nm in diameter were discovered in the cell-free supernatants of C3 cultures. These OMV contain molecules characteristic of bacterial outer membranes, such as lipopolysaccharide and phospholipids...
August 10, 2018: Applied and Environmental Microbiology
Peter van Ulsen, Katinka M Zinner, Wouter S P Jong, Joen Luirink
The classical monomeric autotransporters are ubiquitously used by Gram-negative bacteria to export virulence and colonization factors to their cell surface or into their surroundings. They are expressed as monomeric proteins that pass the inner and outer membrane in two consecutive steps facilitated by the Sec translocon and the Bam complex, respectively. In this mini-review we discuss how autotransporters translocate their secreted functional domains across the outer membrane. We highlight the interactions with the Bam complex and discuss how specific features of the recently solved structure of Bam lead to a mechanistic model for autotransporter secretion...
July 30, 2018: FEMS Microbiology Letters
Branko Velimirov, Carmen Ranftler
Horizontal gene transfer (HGT) was observed by incubation of an amino acid-deficient strain of Escherichia coli (AB1157) with particles gained from an oligotrophic environment, when all deficiencies were restored with frequencies up to 1.94 × 10-5 and no preference for a single marker. Hence, the DNA transfer to the revertant cells was carried out by generalized transduction. Those particles display structural features of outer membrane vesicles (OMVs) but contain high amounts of DNA. Due to a process called serial transduction, the revertant's particles were likewise transferring genetic information to deficient E...
August 6, 2018: Wiener Medizinische Wochenschrift
Frank Gieseler, Corinna Plattfaut, Tabea Quecke, Annika Freund, Hendrik Ungefroren, Fanny Ender
Microvesicles (MVs) represent a subgroup of extracellular vesicles (EVs) emerging from various cells by blebbing of their outer membrane. Therefore, they share features such as membrane composition and antigenicity with their parental cells. Released by many immune and tumor cells, MVs act as intercellular messengers, account for horizontal gene transfer and can activate the coagulation system. With the aim to investigate their relevance for tumor cell biology, we characterized MVs released by human tumor cell lines of various origins in the absence or presence of TNF-α...
August 6, 2018: Cell Biology International
Magnus Paulsson, Karlhans F Che, Jonas Ahl, Johan Tham, Linda Sandblad, Margaretha E Smith, Ingemar Qvarfordt, Yu-Ching Su, Anders Lindén, Kristian Riesbeck
Pathogens causing pneumonia utilize the complement regulator vitronectin to evade complement-mediated killing. Although vitronectin is associated with several chronic lung diseases, the role of bronchoalveolar vitronectin in pneumonia has not been studied. This study sought to reveal the involvement of vitronectin in the bronchoalveolar space during pneumonia, to assess the effect of outer membrane vesicles and endotoxin on vitronectin release, and to determine whether bacterial pathogens utilize pulmonary vitronectin for evasion...
2018: Frontiers in Microbiology
Fernanda Ayane de Oliveira Santos, Nilton Lincopan, Elizabeth De Gaspari
BACKGROUND: The Neisseria meningitidis bacterium is a Gram-negative diplococcus that can be classified into different serogroups according to the capsular structure. Six of them (A, B, C, W, X, Y) are responsible for causing Invasive Meningococcal Disease (IMD). The strategies for the development of a vaccine for serogroup B have been directed to the use of outer membrane vesicles (OMVs). The aim of this study was to evaluate the immunogenicity of antigenic determinants from OMVs of N...
July 19, 2018: Immunobiology
Gaurav Kanojia, René H M Raeven, Larissa van der Maas, Tim H E Bindels, Elly van Riet, Bernard Metz, Peter C Soema, Rimko Ten Have, Henderik W Frijlink, Jean-Pierre Amorij, Gideon F A Kersten
Worldwide resurgence of whooping cough calls for improved, next-generation pertussis vaccines that induce broad and long-lasting immunity. A mucosal pertussis vaccine based on outer membrane vesicles (omvPV) is a promising candidate. Further, a vaccine that is stable outside the cold chain would be of substantial advantage for worldwide distribution and application. A vaccine formulated as a powder could both stabilize the vaccine as well as make it suitable for pulmonary vaccination. To that end, we developed a spray dried omvPV with improved stability compared to the liquid omvPV formulation...
July 23, 2018: Journal of Controlled Release: Official Journal of the Controlled Release Society
Paul Kohl, Franz G Zingl, Thomas O Eichmann, Stefan Schild
Outer membrane vesicles (OMVs) are naturally secreted from the bacterial cell surface and therefore localized in the cell-free supernatant of bacterial cultures. Here we describe methods for crude and density gradient-purified OMV isolation and protocols for control analyses for protein profiling (SDS-PAGE), detection of indicator proteins (immunoblot analysis), lipid profiling (lipid extraction and LC-MS analysis), vesicle size determination (NanoSight), rough estimation of biomass (TrayCell™), as well as quantifications of defined OMV components, e...
2018: Methods in Molecular Biology
K C Courtney, W Pezeshkian, R Raghupathy, C Zhang, A Darbyson, J H Ipsen, D A Ford, H Khandelia, J F Presley, X Zha
Mammalian sphingolipids, primarily with C24 or C16 acyl chains, reside in the outer leaflet of the plasma membrane. Curiously, little is known how C24 sphingolipids impact cholesterol and membrane microdomains. Here, we present evidence that C24 sphingomyelin, when placed in the outer leaflet, suppresses microdomains in giant unilamellar vesicles and also suppresses submicron domains in the plasma membrane of HeLa cells. Free energy calculations suggested that cholesterol has a preference for the inner leaflet if C24 sphingomyelin is in the outer leaflet...
July 24, 2018: Cell Reports
Sebastian Aguayo, Christina Maria Anna Pia Schuh, Benjamin Vicente, Luis Gerardo Aguayo
Alzheimer's disease (AD) is a neurodegenerative condition affecting millions of people worldwide. It is associated with cerebral amyloid-β (Aβ) plaque deposition in the brain, synaptic disconnection, and subsequent progressive neuronal death. Although considerable progress has been made to elucidate the pathogenesis of AD, the specific causes of the disease remain highly unknown. Recent research has suggested a potential association between certain infectious diseases and dementia, either directly due to bacterial brain invasion and toxin production, or indirectly by modulating the immune response...
2018: Journal of Alzheimer's Disease: JAD
Pierangelo Bellio, Carla Luzi, Alisia Mancini, Salvatore Cracchiolo, Maurizio Passacantando, Letizia Di Pietro, Mariagrazia Perilli, Gianfranco Amicosante, Sandro Santucci, Giuseppe Celenza
BACKGROUND: Therapeutic options against Multi Drug Resistant (MDR) pathogens are limited and the overall strategy would be the development of adjuvants able to enhance the activity of therapeutically available antibiotics. Non-specific outer membrane permeabilizer, like metal-oxide nanoparticles, can be used to increase the activity of antibiotics in drug-resistant pathogens. The study aims to investigate the effect of cerium oxide nanoparticles (CeO2 NPs) on bacterial outer membrane permeability and their application in increasing the antibacterial activity of antibiotics against MDR pathogens...
July 17, 2018: Biochimica et Biophysica Acta
Gianluigi De Benedetto, Paola Cescutti, Carlo Giannelli, Roberto Rizzo, Francesca Micoli
In the last years, outer membrane vesicles have attracted a lot of attention for the development of vaccines against bacterial pathogens. Extracellular vesicles can be obtained in high yields by genetic mutations, resulting in generalized modules for membrane antigens (GMMA). Methods to check the quality, consistency of production, and stability of GMMA vaccines are of fundamental importance. In this context, analytical methods for size distribution determination and verifying the integrity and possible aggregation of GMMA particles are strongly needed...
November 30, 2017: ACS Omega
Jinshui Lin, Juanli Cheng, Yao Wang, Xihui Shen
The Pseudomonas quinolone signal (PQS) has been studied primarily in the context of its role as a quorum-sensing signaling molecule. Recent data suggest, however, that this molecule may also function to mediate iron acquisition, cytotoxicity, outer-membrane vesicle biogenesis, or to exert host immune modulatory activities.
2018: Frontiers in Cellular and Infection Microbiology
Othman A Alghamdi, Nicola King, Nicholas M Andronicos, Graham L Jones, Belal Chami, Paul K Witting, Pierre D J Moens
Renal PEPT1 and PEPT2 cotransporters play an important role in the balance of circulating body oligopeptides and selected peptidomimetic drugs. We aim to comprehensively characterise age-related changes of the renal PEPT cotransporters at the gene, protein, and functional level. Brush border membrane vesicles (BBMV) and outer medulla membrane vesicles (OMMV) were isolated from the kidneys of young, middle-aged and old rats. The protein expression of PEPT1 was not only increased in BBMV from old rats, but PEPT1 also appeared in OMMV from middle-aged and old rats...
July 17, 2018: Molecular and Cellular Biochemistry
Lorinda Turner, Natalie J Bitto, David L Steer, Camden Lo, Kimberley D'Costa, Georg Ramm, Mitch Shambrook, Andrew F Hill, Richard L Ferrero, Maria Kaparakis-Liaskos
Gram-negative pathogens ubiquitously shed outer membrane vesicles (OMVs) that play a central role in initiating and regulating pathogenesis in the host. Due to their highly inflammatory nature, OMVs are extensively being examined for their role in mediating disease in addition to their applications in innovative vaccines. A key mechanism whereby OMVs mediate inflammation and disease progression is dependent on their ability to enter host cells. Currently, the role of OMV size on determining their mechanism of cellular entry and their protein composition remains unknown...
2018: Frontiers in Immunology
Dekun Bi, Yue Wang, Yunhang Gao, Xincang Li, Qing Chu, Junxia Cui, Tianjun Xu
Lipopolysaccharide (LPS) is the major component of the outer membrane of Gram-negative bacteria. This molecule can induce strong immune response and various biological effects. In mammals, TLR4 can recognize LPS and induce inflammatory response. However, the innate receptor in fish for recognizing LPS remains ambiguous. LPS can invade the cytoplasm via outer membrane vesicles produced by Gram-negative bacteria and could be detected by intracellular receptor caspase-11 in mammals, so, there may also exist the intracellular receptors that can recognize LPS in fish...
2018: Frontiers in Immunology
Natalie J Bitto, Paul J Baker, Jennifer K Dowling, Georgie Wray-McCann, Amanda De Paoli, Le Son Tran, Pak Ling Leung, Katryn J Stacey, Ashley Mansell, Seth L Masters, Richard L Ferrero
Outer membrane vesicles (OMVs) are constitutively produced by Gram-negative bacteria both in vivo and in vitro. These lipid-bound structures carry a range of immunogenic components derived from the parent cell, which are transported into host target cells and activate the innate immune system. Recent advances in the field have shed light on some of the multifaceted roles of OMVs in host-pathogen interactions. In this study, we investigated the ability of OMVs from two clinically important pathogens, Pseudomonas aeruginosa and Helicobacter pylori, to activate canonical and non-canonical inflammasomes...
July 12, 2018: Immunology and Cell Biology
Daniel Salvi, Sylvain Bournais, Lucas Moyet, Imen Bouchnak, Marcel Kuntz, Christophe Bruley, Norbert Rolland
Plastids contain several key subcompartments. The two limiting envelope membranes (inner and outer membrane of the plastid envelope with an intermembrane space between), an aqueous phase (stroma), and an internal membrane system terms (thylakoids) formed of flat compressed vesicles (grana) and more light structures (lamellae). The thylakoid vesicles delimit another discrete soluble compartment, the thylakoid lumen. AT_CHLORO ( ) is a unique database supplying information about the subplastidial localization of proteins...
2018: Methods in Molecular Biology
Alexander Shulman, Yael Yair, Dvora Biran, Thomas Sura, Andreas Otto, Uri Gophna, Dörte Becher, Michael Hecker, Eliora Z Ron
Many strains of Escherichia coli carry a 29,250-bp ETT2 pathogenicity island (PAI), which includes genes predicted to encode type III secretion system (T3SS) components. Because it is similar to the Salmonella pathogenicity island 1 (SPI-1) system, encoding a T3SS in Salmonella enterica , it was assumed that ETT2 also encodes a secretion system injecting effectors into host cells. This assumption was checked in E. coli serotype O2-associated with urinary tract infections and septicemia-which has an intact ETT2 gene cluster, in contrast to most strains in which this cluster carries deletions and mutations...
July 3, 2018: MBio
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