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Inelastic scattering and solvent scattering reduce dynamical diffraction in biological crystals.

ABSTRACT: Multi-slice simulations of electron diffraction by three-dimensional protein crystals have indicated that structure solution would be severely impeded by dynamical diffraction, especially when crystals are more than a few unit cells thick. In practice, however, dynamical diffraction turned out to be less of a problem than anticipated on the basis of these simulations. Here it is shown that two scattering phenomena, which are usually omitted from multi-slice simulations, reduce the dynamical effect: solvent scattering reduces the phase differences within the exit beam and inelastic scattering followed by elastic scattering results in diffusion of dynamical scattering out of Bragg peaks. Thus, these independent phenomena provide potential reasons for the apparent discrepancy between theory and practice in protein electron crystallography.

SUBMITTER: Latychevskaia T

PROVIDER: S-EPMC6690131 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Inelastic scattering and solvent scattering reduce dynamical diffraction in biological crystals.

Latychevskaia Tatiana T Abrahams Jan Pieter JP

Acta crystallographica Section B, Structural science, crystal engineering and materials 20190801 Pt 4

Multi-slice simulations of electron diffraction by three-dimensional protein crystals have indicated that structure solution would be severely impeded by dynamical diffraction, especially when crystals are more than a few unit cells thick. In practice, however, dynamical diffraction turned out to be less of a problem than anticipated on the basis of these simulations. Here it is shown that two scattering phenomena, which are usually omitted from multi-slice simulations, reduce the dynamical effe ...[more]

PMID: 32830710

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