1xex
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Structural biochemistry of ATP-driven dimerization and DNA stimulated activation of SMC ATPases.
OverviewOverview
Structural maintenance of chromosome (SMC) proteins play a central role in, higher-order chromosome structure in all kingdoms of life. SMC proteins, consist of a long coiled-coil domain that joins an ATP binding cassette, (ABC) ATPase domain on one side and a dimerization domain on the other, side. SMC proteins require ATP binding or hydrolysis to promote cohesion, and condensation, which is suggested to proceed via formation of SMC rings, or assemblies. To learn more about the role of ATP in the architecture of, SMC proteins, we report crystal structures of nucleotide-free and ATP, bound P. furiosus SMC ATPase domains. ATP dimerizes two SMC ATPase domains, by binding to opposing Walker A and signature motifs, indicating that ATP, binding can directly assemble SMC proteins. DNA stimulates ATP hydrolysis, in the engaged SMC ABC domains, suggesting that ATP hydrolysis can be, allosterically regulated. Structural and mutagenesis data identify an SMC, protein conserved-arginine finger that is required for DNA stimulation of, the ATPase activity and directly connects a putative DNA interaction site, to ATP. Our results suggest that stimulation of the SMC ATPase activity, may be a specific feature to regulate the ATP-driven assembly and, disassembly of SMC proteins.
About this StructureAbout this Structure
1XEX is a Protein complex structure of sequences from Pyrococcus furiosus with MG and ATP as ligands. Full crystallographic information is available from OCA.
ReferenceReference
Structural biochemistry of ATP-driven dimerization and DNA-stimulated activation of SMC ATPases., Lammens A, Schele A, Hopfner KP, Curr Biol. 2004 Oct 5;14(19):1778-82. PMID:15458651
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