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Updated: May 7, 2026

Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers
Published on: September 19, 2017
Is There Any Proton Exchange Between Ammonium Ions localized Within the d(G3T4G4)2 Quadruplex?
Abstract:
It is generally appreciated that stability, dynamics and function of nucleic acids are affected by nature of cations that are involved in interaction with specific functionalities. DNA G-quadruplexes are unique among nucleic acid structures in their metal ion requirements. Cations inside G-quadruplex structures have been shown to exchange between binding sites and bulk solution. However, in d(G3T4G4)2 G-quadruplex ammonium ions do not exchange through the central G-quartet plane. Passage of larger cations through a G-quartet such as potassium or ammonium ions requires partial opening of G-quartets. The use of HzExHSQC experiment demonstrates that smaller protons move through the central G-quartet plane.
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