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2hcb
From Proteopedia
Structure of AMPPCP-bound DnaA from Aquifex aeolicus
Overview
In bacteria, the initiation of replication is controlled by DnaA, a member of the ATPases associated with various cellular activities (AAA+) protein superfamily. ATP binding allows DnaA to transition from a monomeric state into a large oligomeric complex that remodels replication origins, triggers duplex melting and facilitates replisome assembly. The crystal structure of AMP-PCP-bound DnaA reveals a right-handed superhelix defined by specific protein-ATP interactions. The observed quaternary structure of DnaA, along with topology footprint assays, indicates that a right-handed DNA wrap is formed around the initiation nucleoprotein complex. This model clarifies how DnaA engages and unwinds bacterial origins and suggests that additional, regulatory AAA+ proteins engage DnaA at filament ends. Eukaryotic and archaeal initiators also have the structural elements that promote open-helix formation, indicating that a spiral, open-ring AAA+ assembly forms the core element of initiators in all domains of life.
About this Structure
2HCB is a Single protein structure of sequence from Aquifex aeolicus. Full crystallographic information is available from OCA.
Reference
Structural basis for ATP-dependent DnaA assembly and replication-origin remodeling., Erzberger JP, Mott ML, Berger JM, Nat Struct Mol Biol. 2006 Aug;13(8):676-83. Epub 2006 Jul 9. PMID:16829961 Page seeded by OCA on Sun May 4 06:07:00 2008
