1oxt
From Proteopedia
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Crystal structure of GlcV, the ABC-ATPase of the glucose ABC transporter from Sulfolobus solfataricus
Overview
The ABC-ATPase GlcV energizes a binding protein-dependent ABC transporter, that mediates glucose uptake in Sulfolobus solfataricus. Here, we report, high-resolution crystal structures of GlcV in different states along its, catalytic cycle: distinct monomeric nucleotide-free states and monomeric, complexes with ADP-Mg(2+) as a product-bound state, and with AMPPNP-Mg(2+), as an ATP-like bound state. The structure of GlcV consists of a typical, ABC-ATPase domain, comprising two subdomains, connected by a linker region, to a C-terminal domain of unknown function. Comparisons of the, nucleotide-free and nucleotide-bound structures of GlcV reveal, re-orientations of the ABCalpha subdomain and the C-terminal domain, relative to the ABCalpha/beta subdomain, and switch-like rearrangements in, the P-loop and Q-loop regions. Additionally, large conformational, differences are observed between the GlcV structures and those of other, ABC-ATPases, further emphasizing the inherent flexibility of these, proteins. Notably, a comparison of the monomeric AMPPNP-Mg(2+)-bound GlcV, structure with that of the dimeric ATP-Na(+)-bound LolD-E171Q mutant, reveals a +/-20 degrees rigid body re-orientation of the ABCalpha, subdomain relative to the ABCalpha/beta subdomain, accompanied by a local, conformational difference in the Q-loop. We propose that these differences, represent conformational changes that may have a role in the mechanism of, energy-transduction and/or allosteric control of the ABC-ATPase activity, in bacterial importers.
About this Structure
1OXT is a Single protein structure of sequence from Sulfolobus solfataricus. Full crystallographic information is available from OCA.
Reference
Crystal structures of the ATPase subunit of the glucose ABC transporter from Sulfolobus solfataricus: nucleotide-free and nucleotide-bound conformations., Verdon G, Albers SV, Dijkstra BW, Driessen AJ, Thunnissen AM, J Mol Biol. 2003 Jul 4;330(2):343-58. PMID:12823973
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