2rh5
From Proteopedia
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Structure of Apo Adenylate Kinase from Aquifex Aeolicus
Overview
The mechanisms by which enzymes achieve extraordinary rate acceleration, and specificity have long been of key interest in biochemistry. It is, generally recognized that substrate binding coupled to conformational, changes of the substrate-enzyme complex aligns the reactive groups in an, optimal environment for efficient chemistry. Although chemical mechanisms, have been elucidated for many enzymes, the question of how enzymes achieve, the catalytically competent state has only recently become approachable by, experiment and computation. Here we show crystallographic evidence for, conformational substates along the trajectory towards the catalytically, competent 'closed' state in the ligand-free form of the enzyme adenylate, kinase. Molecular dynamics simulations indicate that these partially, closed conformations are sampled in nanoseconds, whereas nuclear magnetic, resonance and single-molecule fluorescence resonance energy transfer, reveal rare sampling of a fully closed conformation occurring on the, microsecond-to-millisecond timescale. Thus, the larger-scale motions in, substrate-free adenylate kinase are not random, but preferentially follow, the pathways that create the configuration capable of proficient, chemistry. Such preferred directionality, encoded in the fold, may, contribute to catalysis in many enzymes.
About this Structure
2RH5 is a Single protein structure of sequence from Aquifex aeolicus. Active as Adenylate kinase, with EC number 2.7.4.3 Full crystallographic information is available from OCA.
Reference
Intrinsic motions along an enzymatic reaction trajectory., Henzler-Wildman KA, Thai V, Lei M, Ott M, Wolf-Watz M, Fenn T, Pozharski E, Wilson MA, Petsko GA, Karplus M, Hubner CG, Kern D, Nature. 2007 Dec 6;450(7171):838-44. Epub 2007 Nov 18. PMID:18026086
Page seeded by OCA on Wed Jan 23 11:35:44 2008
