2qe7
From Proteopedia
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Crystal structure of the f1-atpase from the thermoalkaliphilic bacterium bacillus sp. ta2.a1
Overview
The ATP synthase of the thermoalkaliphilic Bacillus sp. TA2.A1 operates, exclusively in ATP synthesis direction. In the crystal structure of the, nucleotide-free alpha(3)beta(3)gamma epsilon subcomplex (TA2F(1)) at 3.1 A, resolution, all three beta subunits adopt the open beta(E) conformation., The structure shows salt bridges between the helix-turn-helix motif of the, C-terminal domain of the beta(E) subunit (residues Asp372 and Asp375) and, the N-terminal helix of the gamma subunit (residues Arg9 and Arg10). These, electrostatic forces pull the gamma shaft out of the rotational center and, impede rotation through steric interference with the beta(E) subunit., Replacement of Arg9 and Arg10 with glutamines eliminates the salt bridges, and results in an activation of ATP hydrolysis activity, suggesting that, these salt bridges prevent the native enzyme from rotating in ATP, hydrolysis direction. A similar bending of the gamma shaft as in the, TA2F(1) structure was observed by single-particle analysis of the, TA2F(1)F(o) holoenzyme.
About this Structure
2QE7 is a Protein complex structure of sequences from Bacillus sp. t42. Active as H(+)-transporting two-sector ATPase, with EC number 3.6.3.14 Full crystallographic information is available from OCA.
Reference
The structural basis for unidirectional rotation of thermoalkaliphilic F1-ATPase., Stocker A, Keis S, Vonck J, Cook GM, Dimroth P, Structure. 2007 Aug;15(8):904-14. PMID:17697996
Page seeded by OCA on Wed Jan 23 13:43:54 2008
