The goal of the NYSBC cryoelectron microscopy facility is to help researchers elucidate the intermolecular interactions and domain architectures of macromolecules within their native cellular assemblies. Towards this goal, the facility has brought together a combination of instrumentation and staff expertise that supports the determination three-dimensional structures using the four major techniques available to the field: two-dimensional crystals, helical assemblies, single particles analysis and tomography.

The first three techniques are applicable to samples that can be biochemically isolated; these samples require high purity as well as a high degree of structural homogeneity. These are the techniques that produce the highest resolution, which can approach atomic resolution in favorable cases. Fitting atomic models to the resulting structures is a common approach for interpreting the resulting structures and deducing interactions between domains or subunits of a larger assembly. Electron tomography, in contrast, can be used to visualize highly-complex and heterogeneous samples, such as tissue sections, or pleomorphic assemblies such as liposomes. Since there is often no aid from innate symmetry, the resolution achieved with electron tomography is lower, but still sufficient for evaluating the topology of organelles or distributions of macromolecular assemblies across the surface of a virus.

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