1svj
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="1svj" size="450" color="white" frame="true" align="right" spinBox="true" caption="1svj" /> '''The solution structure of the nucleotide bin...)
Next diff →
Revision as of 00:38, 21 November 2007
|
The solution structure of the nucleotide binding domain of KdpB
Overview
P-type ATPases are involved in the active transport of ions across, biological membranes. The KdpFABC complex (P-type ATPase) of Escherichia, coli is a high-affinity K+ uptake system that operates only when the cell, experiences osmotic stress or K+ limitation. Here, we present the solution, structure of the nucleotide binding domain of KdpB (backbone RMSD 0.17 A), and a model of the AMP-PNP binding mode based on intermolecular distance, restraints. The calculated AMP-PNP binding mode shows the purine ring of, the nucleotide to be "clipped" into the binding pocket via a, pi-pi-interaction to F377 on one side and a cation-pi-interaction to K395, on the other. This binding mechanism seems to be conserved in all P-type, ATPases, except the heavy metal transporting ATPases (type IB). Thus, we, conclude that the Kdp-ATPase (currently type IA) is misgrouped and has, more similarities to type III ATPases. The KdpB N-domain is the smallest, and simplest known for a P-type ATPase, and represents a minimal example, of this functional unit. No evidence of significant conformational changes, was observed within the N-domain upon nucleotide binding, thus ruling out, a role for ATP-induced conformational changes in the reaction cycle.
About this Structure
1SVJ is a Single protein structure of sequence from Escherichia coli. Active as Potassium-transporting ATPase, with EC number 3.6.3.12 Full crystallographic information is available from OCA.
Reference
Inter-domain motions of the N-domain of the KdpFABC complex, a P-type ATPase, are not driven by ATP-induced conformational changes., Haupt M, Bramkamp M, Coles M, Altendorf K, Kessler H, J Mol Biol. 2004 Oct 1;342(5):1547-58. PMID:15364580
Page seeded by OCA on Wed Nov 21 02:45:45 2007
