4NMN

Aquifex aeolicus replicative helicase (DnaB) complexed with ADP, at 3.3 resolution

Summary for 4NMN

• Entry DOI: 10.2210/pdb4nmn/pdb
• Related: 2R6A 4ESV
• EMDB information: 2321 2322 2508
• Descriptor: Replicative DNA helicase, ADENOSINE-5'-DIPHOSPHATE, MAGNESIUM ION, ... (5 entities in total)
• Functional Keywords: reca-type helicase, replicative dna helicase, atp binding, dna-binding, replication
• Biological source: Aquifex aeolicus
• Total number of polymer chains: 2
• Total formula weight: 100387.16

Authors

Lyubimov, A.Y.,Strycharska, M.S.,Erzberger, J.P.,Berger, J.M. (deposition date: 2013-11-15, release date: 2014-01-29, Last modification date: 2024-11-27)

Primary citation

Strycharska, M.S.,Arias-Palomo, E.,Lyubimov, A.Y.,Erzberger, J.P.,O'Shea, V.L.,Bustamante, C.J.,Berger, J.M.
Nucleotide and partner-protein control of bacterial replicative helicase structure and function.
Mol.Cell, 52:844-854, 2013

PubMed Abstract: Cellular replication forks are powered by ring-shaped, hexameric helicases that encircle and unwind DNA. To better understand the molecular mechanisms and control of these enzymes, we used multiple methods to investigate the bacterial replicative helicase, DnaB. A 3.3 Å crystal structure of Aquifex aeolicus DnaB, complexed with nucleotide, reveals a newly discovered conformational state for this motor protein. Electron microscopy and small angle X-ray scattering studies confirm the state seen crystallographically, showing that the DnaB ATPase domains and an associated N-terminal collar transition between two physical states in a nucleotide-dependent manner. Mutant helicases locked in either collar state are active but display different capacities to support critical activities such as duplex translocation and primase-dependent RNA synthesis. Our findings establish the DnaB collar as an autoregulatory hub that controls the ability of the helicase to transition between different functional states in response to both nucleotide and replication initiation/elongation factors.

PubMed: 24373746
DOI: 10.1016/j.molcel.2013.11.016

Experimental method

X-RAY DIFFRACTION (3.301 Å)