Arthur T Knackerbracket has found the following story:
Research published in the Proceedings of the National Academy of Sciences describes a new approach for creating synthetic cell membrane mimics. Using a new approach for "click" chemistry, researchers designed self-organizing nanovesicles that can have their surfaces decorated with similar sugar molecules as viruses, bacteria, or living cells. The result of a collaboration between Penn, Temple University, the Max Planck Institute, the Leibniz Institute for Interactive Materials, RWTH Aachen University, and Freie Universität Berlin, this work provides a new tool for studying how certain pathogens, such as the novel coronavirus, can evade detection by a host's immune system.
The outer layers of cells are decorated with proteins, lipids, and sugar molecules that are used for communicating with and recognizing other cells. One of the most common types of sugars is mannose, which is found in long, branched chains and is also connected to other biomolecules. These oligomannoses are also commonly found on bacteria and viruses and are thought to help pathogens avoid being detected by a host's immune system; however, the precise way that these sugars help pathogens evade detection is not well understood.
One approach to study cellular interactions is to create synthetic cells that can have customized sequences of sugars or proteins, allowing scientists to answer specific questions about how cells work. Previous research by the same team used these synthetic cells to better understand how short-chain sugars act as "communication channels." Now, using these same cell mimics, the researchers were interested in understanding the role of complex sugars, including oligomannose, which are more akin to what's prevalent on cell and pathogen surfaces.
[...] the researchers developed a new approach to synthesize their cell mimics through "click" chemistry, where two smaller molecules are linked together to form a larger molecule that only requires a small amount of starting material. They found that an isothiocyanate-amine reaction, used for protein sequencing but never before for click chemistry, was able to add large sugar molecules to the outsides of the synthetic cells. "That provided us with a tool to investigate these sugars on the surface of a cell-like assembly," says Virgil Percec. "You make the hydrophobic character to become hydrophilic and provide the structure that we could not have accessed through other chemistry."
With their new tool in hand, the researchers used methods previously developed by the team to study their self-assembled nanostructures, including cryo-EM to visualize the cell mimics and AFM to study their surface morphology. By looking at a subset of cell mimics that contained oligomannose sequences similar to that of a typical cell, they found that longer sugars could bind to other cell surfaces with more strength and greater efficiency.
More information: Qi Xiao et al. Nanovesicles displaying functional linear and branched oligomannose self-assembled from sequence-defined Janus glycodendrimers, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2003938117
(Score: 0) by Anonymous Coward on Friday May 22 2020, @12:53PM
Can this technique be used to manufacture smallpox? Asking for my friend Mohammed.