4R7Z

PfMCM-AAA double-octamer

Summary for 4R7Z

• Entry DOI: 10.2210/pdb4r7z/pdb
• Related: 4R7Y
• Descriptor: Cell division control protein 21, ADENOSINE-5'-DIPHOSPHATE, MAGNESIUM ION (3 entities in total)
• Functional Keywords: aaa+, mcm, helicase, atpase, dna replication, hydrolase
• Biological source: Pyrococcus furiosus; More
• Total number of polymer chains: 16
• Total formula weight: 602189.73

Authors

Miller, J.M.,Arachea, B.T.,Epling, L.B.,Enemark, E.J. (deposition date: 2014-08-28, release date: 2014-10-08, Last modification date: 2023-09-20)

Primary citation

Miller, J.M.,Arachea, B.T.,Epling, L.B.,Enemark, E.J.
Analysis of the crystal structure of an active MCM hexamer.
Elife, 3:e03433-e03433, 2014

PubMed Abstract: In a previous Research article (Froelich et al., 2014), we suggested an MCM helicase activation mechanism, but were limited in discussing the ATPase domain because it was absent from the crystal structure. Here we present the crystal structure of a nearly full-length MCM hexamer that is helicase-active and thus has all features essential for unwinding DNA. The structure is a chimera of Sulfolobus solfataricus N-terminal domain and Pyrococcus furiosus ATPase domain. We discuss three major findings: 1) a novel conformation for the A-subdomain that could play a role in MCM regulation; 2) interaction of a universally conserved glutamine in the N-terminal Allosteric Communication Loop with the AAA+ domain helix-2-insert (h2i); and 3) a recessed binding pocket for the MCM ssDNA-binding motif influenced by the h2i. We suggest that during helicase activation, the h2i clamps down on the leading strand to facilitate strand retention and regulate ATP hydrolysis.

PubMed: 25262915
DOI: 10.7554/eLife.03433

Experimental method

X-RAY DIFFRACTION (3.8 Å)