Mechanistic details of a protein-protein association pathway revealed by paramagnetic relaxation enhancement titration measurements.

ABSTRACT: Protein-protein association generally proceeds via the intermediary of a transient, lowly populated, encounter complex ensemble. The mechanism whereby the interacting molecules in this ensemble locate their final stereospecific structure is poorly understood. Further, a fundamental question is whether the encounter complex ensemble is an effectively homogeneous population of nonspecific complexes or whether it comprises a set of distinct structural and thermodynamic states. Here we use intermolecular paramagnetic relaxation enhancement (PRE), a technique that is exquisitely sensitive to lowly populated states in the fast exchange regime, to characterize the mechanistic details of the transient encounter complex interactions between the N-terminal domain of Enzyme I (EIN) and the histidine-

SUBMITTER: Fawzi NL 

PROVIDER: S-EPMC2824347 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature