Surface Modification of E. coli Outer Membrane Vesicles with Glycosylphosphatidylinositol-Anchored Proteins: Generating Pro/Eukaryote Chimera Constructs

Abstract

Extracellular vesicles produced by different types of cells have recently attracted great attention, not only for their role in physiology and pathology, but also because of the emerging applications in gene therapy, vaccine production and diagnostics. Less well known than their eukaryotic counterpart, also bacteria produce extracellular vesicles, in the case of the Gram-negative E. coli the main species is termed outer membrane vesicles (OMVs). In this study, we show for the first time the functional surface modification of E. coli OMVs with glycosylphosphatidylinositol (GPI)-anchored protein, exploiting a process variably described as molecular painting or protein engineering in eukaryotic membranes, whereby the lipid part of the GPI anchor inserts in cell membranes. By transferring the process to bacterial vesicles, we can generate a hybrid of perfectly eukaryotic proteins (in terms of folding and post-translational modifications) on a prokaryotic platform. We could demonstrate that two different GPI proteins can be displayed on the same OMV. In addition to fluorescent marker proteins, cytokines, growth factors and antigens canb be potentially transferred, generating a versatile modular platform for a novel vaccine strategy.

Evaluating the coating process of titanium dioxide nanoparticles and sodium tripolyphosphate on cucumbers under chilling condition to extend the shelf-life

“…Nano-coatings may reduce the deteriorative changes by decreasing desiccation, yellowing, and shriveling 5 – 8 . According to the previous reports, the visual quality was preserved by using edible coatings, chemical components such as sodium tripolyphosphate, and antibacterial agents such as nisin, thymol, and tween during the storage period 12 – 22 . Olawuyi and Lee 30 , reported similar results of the visual quality after treating fresh-cut cucumbers with chitosan and other packaging materials.…”

“…Chitosan is biodegradable and can maintain color, prevent water loss, softening, delay ripening, fungal rot, and inhibit respiration 10 , 11 . Nano-coating processes can reduce physiological weight loss, decay, microbial growth, maintain firmness, protect the quality, inhibit the color changes, enzymes, and prevent senescence 12 , 13 . Nano-material films act as action items for enhancing flavors, nutrients against pathogen growth on the surface of foods 14 , 15 .…”

(Patho)Physiology of Glycosylphosphatidylinositol-Anchored Proteins I: Localization at Plasma Membranes and Extracellular Compartments

“…(vi) Full-length GPI-APs incorporated into detergent-or (lyso)phospholipid-/cholesterolcontaining mixed micelles can be inserted into liposomes as well as PMs of intact cells in vitro under conservation of their activity, a process previously called cell surface painting [347,348].…”

Extracellular Vesicles and Their Membranes: Exosomes vs. Virus-Related Particles

“…Both cells of eukaryotic and prokaryotic origin produce extracellular vesicles (EVEs, for an overview of vesicle types and abbreviations, see Table 1). In bacteria, they contribute to horizontal gene transfer, waste disposal, organization of biofilms, and general inter-cell communication [1,2]. EVEs constitute the vesicular fraction of the cellular proteome [3].…”