6CRM

Crystal Structure of RecQ catalytic core from C. sakazakii bound to an unfolded G-quadruplex

Summary for 6CRM

• Entry DOI: 10.2210/pdb6crm/pdb
• Descriptor: RecQ, DNA (5'-D(P*GP*GP*GP*TP*CP*GP*GP*TP*GP*CP*CP*TP*TP*A)-3'), ZINC ION, ... (4 entities in total)
• Functional Keywords: g-quadruplex, helicase, hydrolase, hydrolase-dna complex, hydrolase/dna
• Biological source: Cronobacter sakazakii (strain ATCC BAA-894) (Enterobacter sakazakii); More
• Total number of polymer chains: 2
• Total formula weight: 72081.06

Authors

Voter, A.F.,Keck, J.L. (deposition date: 2018-03-19, release date: 2018-10-17, Last modification date: 2023-10-04)

Primary citation

Voter, A.F.,Qiu, Y.,Tippana, R.,Myong, S.,Keck, J.L.
A guanine-flipping and sequestration mechanism for G-quadruplex unwinding by RecQ helicases.
Nat Commun, 9:4201-4201, 2018

PubMed Abstract: Homeostatic regulation of G-quadruplexes (G4s), four-stranded structures that can form in guanine-rich nucleic acids, requires G4 unwinding helicases. The mechanisms that mediate G4 unwinding remain unknown. We report the structure of a bacterial RecQ DNA helicase bound to resolved G4 DNA. Unexpectedly, a guanine base from the unwound G4 is sequestered within a guanine-specific binding pocket. Disruption of the pocket in RecQ blocks G4 unwinding, but not G4 binding or duplex DNA unwinding, indicating its essential role in structure-specific G4 resolution. A novel guanine-flipping and sequestration model that may be applicable to other G4-resolving helicases emerges from these studies.

PubMed: 30305632
DOI: 10.1038/s41467-018-06751-8

Experimental method

X-RAY DIFFRACTION (2.19286241172 Å)