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bioRxiv · 10.1101/580167

High-resolution cryo-EM structures of outbreak strain human norovirus shells reveal size variations

Jung, J.·Grant, T.·Thomas, D. R.·Diehnelt, C. W.·Grigorieff, N.·Joshua-Tor, L.
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Abstract

Noroviruses are a leading cause of food-borne illnesses worldwide. Although GII.4 strains have been responsible for most norovirus outbreaks, the assembled virus shell structures have been available in detail for only a single strain (GI.1). We present high-resolution (2.6-4.1 [A]) cryo-electron microscopy (cryo-EM) structures of GII.4, GII.2, GI.7 and GI.1 human norovirus outbreak strain virus-like particles (VLPs). Although norovirus VLPs have been thought to exist in a single-sized assembly, our structures reveal polymorphism between and within genogroups with small, medium and large particle sizes observed. We developed a new asymmetric reconstruction method and resolved a metal ion adjacent to the co-receptor binding site, which affected the structural stability of the shell. Our structures serve as valuable templates for facilitating vaccine formulations.

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Jung, J., Grant, T., Thomas, D. R., Diehnelt, C. W., Grigorieff, N., Joshua-Tor, L.. 2019-03-16. High-resolution cryo-EM structures of outbreak strain human norovirus shells reveal size variations. https://doi.org/10.1101/580167

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