Professor Willy Wriggers
The Scripps Research Institute
La Jolla, California

Thursday, October 18, 2001
3:00 pm (CT)
3269 Beckman Institute

Abstract

The components of sub-cellular biomolecular 'machines' undergo a wide range of motions that can be modeled with rigid-body and flexible fitting strategies. We present a novel rigid-body fitting approach for the registration of atomic structures with low-resolution densities that takes advantage of Fourier correlation theory to rapidly scan the translational and rotational pose of a probe molecule relative to a (fixed) target density map. The studies demonstrate that electronmicroscopy reconstructions of macromolecular assemblies exhibit low-resolution shapes that might deviate from the known atomic structures of their components. For example, RNA polymerase structures exhibit considerable flexing motions that cannot be explained by rigidly docked sub-units alone. We present novel 3D motion capture techniques based on molecular dynamics simulation and point landmarks that bring such deviating global features of biopolymers into register, while locally preserving their known atomic structure. target density map. The studies demonstrate that electronmicroscopy reconstructions of macromolecular assemblies exhibit low-resolution shapes that might deviate from the known atomic structures of their components. For example, RNA polymerase structures exhibit considerable flexing motions that cannot be explained by rigidly docked sub-units alone. We present novel 3D motion capture techniques based on molecular dynamics simulation and point landmarks that bring such deviating global features of biopolymers into register, while locally preserving their known atomic structure.

Tea and coffee will be served in R3151 Beckman Institute at 2:15pm.