It was previously shown that interstrand cross-linking can further enhance the binding event.
Joke Elskens, Alex Manicardi, Valentina Costi, Annemieke Madder, Roberto Corradini 2017, 'Synthesis and Improved Cross-Linking Properties of C5-Modified Furan Bearing PNAs',Moleculeshttps://www.mdpi.com/1420-3049/22/11/2010. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
In the β-linked polyester, the side chains are carboxylic acid groups capable of forming interstrand double hydrogen bonds.
Brian R. Francis 2015, 'The Hypothesis that the Genetic Code Originated in Coupled Synthesis of Proteins andthe Evolutionary Predecessors of Nucleic Acids in Primitive Cells', Lifehttp://www.mdpi.com/2075-1729/5/1/467. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
Several topology classes of interstrand quadruplex-forming sequences are possible, and different topologies are enriched in different types of structural elements.
Andrzej S Kudlicki 2016, 'G-Quadruplexes Involving Both Strands of Genomic DNA Are Highly Abundant and Colocalizewith Functional Sites in the Human Genome.', PLoS ONEhttp://europepmc.org/articles/PMC4699641?pdf=render. Retrieved from PLOS CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)