Faculty Research

Title

The Sampling of Conformational Dynamics in Ambient-Temperature Crystal Structures of Arginine Kinase

Document Type

Article

Publication Date

2016

Abstract

Arginine kinase provides a model for functional dynamics, studied through crystallography, enzymology, and nuclear magnetic resonance. Structures are now solved, at ambient temperature, for the transition state analog (TSA) complex. Analysis of quasi-rigid sub-domain displacements show that differences between the two TSA structures average about 5% of changes between substrate-free and TSA forms, and they are nearly co-linear. Small backbone hinge rotations map to sites that also flex on substrate binding. Anisotropic atomic displacement parameters (ADPs) are refined using rigid-body TLS constraints. Consistency between crystal forms shows that they reflect intrinsic molecular properties more than crystal lattice effects. In many regions, the favored directions of thermal/static displacement are appreciably correlated with movements on substrate binding. Correlation between ADPs and larger substrate-associated movements implies that the latter approximately follow paths of low-energy intrinsic motions.

Comments

Publication Information.

Godsey, M. H., Davulcu, O., Nix, J. C., Skalicky, J. J., Brüschweiler, R. P., & Chapman, M. S. (2016). The sampling of conformational dynamics in ambient-temperature crystal structures of arginine kinase. Structure. doi:10.1016/j.str.2016.07.013

DOI

10.1016/j.str.2016.07.013