Hydrogen bond coupling in the ketosteroid isomerase active site.

ABSTRACT: Hydrogen bond networks are key elements of biological structure and function. Nevertheless, their structural properties are challenging to assess within complex macromolecules. Hydrogen-bonded protons are not observed in the vast majority of protein X-ray structures, and static crystallographic models provide limited information regarding the dynamical coupling within hydrogen bond networks. We have brought together 1.1-1.3 A resolution X-ray crystallography, (1)H NMR, site-directed mutagenesis, and deuterium isotope effects on the geometry and chemical shifts of hydrogen-bonded protons to probe the conformational coupling of hydrogen bonds donated by Y16 and D103 in the oxyanion hole of bacterial ketosteroid isomerase. Our results suggest a robust physical coupling of the equilibrium stru

SUBMITTER: Sigala PA 

PROVIDER: S-EPMC3393856 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature