On the Stability of DNA Origami Nanostructures in Low‐Magnesium Buffers. Issue 30 (19th June 2018)

• Record Type: Journal Article
• Authors: Kielar, Charlotte; Xin, Yang; Shen, Boxuan; Kostiainen, Mauri A.; Grundmeier, Guido; Linko, Veikko; Keller, Adrian
• Is Part Of: Angewandte Chemie international edition. Volume 57:Issue 30(2018)
• Page Start: 9470
• Page End: 9474
• Publication Date: 2018-06-19
• Subjects: atomic force microscopy -- DNA nanotechnology -- DNA origami -- magnesium -- stability; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201802890
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: DNA origami structures have great potential as functional platforms in various biomedical applications. Many applications, however, are incompatible with the high Mg 2+ concentrations commonly believed to be a prerequisite for maintaining DNA origami integrity. Herein, we investigate DNA origami stability in low‐Mg 2+ buffers. DNA origami stability is found to crucially depend on the availability of residual Mg 2+ ions for screening electrostatic repulsion. The presence of EDTA and phosphate ions may thus facilitate DNA origami denaturation by displacing Mg 2+ ions from the DNA backbone and reducing the strength of the Mg 2+ –DNA interaction, respectively. Most remarkably, these buffer dependencies are affected by DNA origami superstructure. However, by rationally selecting buffer components and considering superstructure‐dependent effects, the structural integrity of a given DNA origami nanostructure can be maintained in conventional buffers even at Mg 2+ concentrations in the low‐micromolar range. Abstract : The stability of DNA origami nanostructures in various Tris and phosphate‐based buffers was evaluated at residual Mg 2+ concentrations in the low‐micromolar range. DNA origami stability was found to be crucially affected by the presence of EDTA and phosphate ions that may displace bound Mg 2+ ions from the DNA backbone and reduce the strength of the Mg 2+ –DNA interaction, respectively. These effects furthermore depend on DNA origami superstructure.