3BOS

Crystal structure of a putative dna replication regulator HDA (SAMA_1916) from Shewanella amazonensis sb2b at 1.75 A resolution

Summary for 3BOS

• Entry DOI: 10.2210/pdb3bos/pdb
• Descriptor: Putative DNA replication factor, MAGNESIUM ION, THIOCYANATE ION, ... (8 entities in total)
• Functional Keywords: p-loop containing nucleoside triphosphate hydrolases, structural genomics, joint center for structural genomics, jcsg, protein structure initiative, psi-2, hydrolase regulator, dna binding protein
• Biological source: Shewanella amazonensis
• Total number of polymer chains: 2
• Total formula weight: 56870.93

Authors

Joint Center for Structural Genomics (JCSG) (deposition date: 2007-12-17, release date: 2008-01-15, Last modification date: 2024-11-20)

Primary citation

Xu, Q.,McMullan, D.,Abdubek, P.,Astakhova, T.,Carlton, D.,Chen, C.,Chiu, H.J.,Clayton, T.,Das, D.,Deller, M.C.,Duan, L.,Elsliger, M.A.,Feuerhelm, J.,Hale, J.,Han, G.W.,Jaroszewski, L.,Jin, K.K.,Johnson, H.A.,Klock, H.E.,Knuth, M.W.,Kozbial, P.,Sri Krishna, S.,Kumar, A.,Marciano, D.,Miller, M.D.,Morse, A.T.,Nigoghossian, E.,Nopakun, A.,Okach, L.,Oommachen, S.,Paulsen, J.,Puckett, C.,Reyes, R.,Rife, C.L.,Sefcovic, N.,Trame, C.,van den Bedem, H.,Weekes, D.,Hodgson, K.O.,Wooley, J.,Deacon, A.M.,Godzik, A.,Lesley, S.A.,Wilson, I.A.
A structural basis for the regulatory inactivation of DnaA.
J.Mol.Biol., 385:368-380, 2009

PubMed Abstract: Regulatory inactivation of DnaA is dependent on Hda (homologous to DnaA), a protein homologous to the AAA+ (ATPases associated with diverse cellular activities) ATPase region of the replication initiator DnaA. When bound to the sliding clamp loaded onto duplex DNA, Hda can stimulate the transformation of active DnaA-ATP into inactive DnaA-ADP. The crystal structure of Hda from Shewanella amazonensis SB2B at 1.75 A resolution reveals that Hda resembles typical AAA+ ATPases. The arrangement of the two subdomains in Hda (residues 1-174 and 175-241) differs dramatically from that of DnaA. A CDP molecule anchors the Hda domains in a conformation that promotes dimer formation. The Hda dimer adopts a novel oligomeric assembly for AAA+ proteins in which the arginine finger, crucial for ATP hydrolysis, is fully exposed and available to hydrolyze DnaA-ATP through a typical AAA+ type of mechanism. The sliding clamp binding motifs at the N-terminus of each Hda monomer are partially buried and combine to form an antiparallel beta-sheet at the dimer interface. The inaccessibility of the clamp binding motifs in the CDP-bound structure of Hda suggests that conformational changes are required for Hda to form a functional complex with the clamp. Thus, the CDP-bound Hda dimer likely represents an inactive form of Hda.

PubMed: 19000695
DOI: 10.1016/j.jmb.2008.10.059

Experimental method

X-RAY DIFFRACTION (1.75 Å)