Visualizing viral assemblies in a nanoscale biosphere

Gilmore, Brian L., Shannon P. Showalter, Madeline J. Dukes, Justin R. Tanner, Andrew C. Demmert, Sarah M. McDonald and Deborah F. Kelly., 2012

Image courtesy of Lab on Chip

Abstract

We present a novel microfluidic platform to examine biological assemblies at high-resolution. We have engineered a functionalized chamber that serves as a “nanoscale biosphere” to capture and maintain rotavirus double-layered particles (DLPs) in a liquid environment. The chamber can be inserted into the column of a transmission electron microscope while being completely isolated from the vacuum system. This configuration allowed us to determine the structure of biological complexes at nanometer-resolution within a self-contained vessel. Images of DLPs were used to calculate the first 3D view of macromolecules in solution. We refer to this new fluidic visualization technology as in situ molecular microscopy

Impact Statement

First example of 3D reconstruction of a biological particle from liquid in situ TEM images. A 25 Å reconstruction was obtained from 600 double layer rotavirus particles imaged in a 150 nm liquid layer. Multiple subpopulations were identified, several of which, are not observed in cryo-prepared samples indicating the dynamic state of samples in liquid versus those embedded in ice.
Keywords: Virus; Resolution