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Nanomanipulation of Single RNA Molecules by Optical Tweezers
Published on: August 20, 2014
Knotted folds induced by homochiral all-parallel (or all-antiparallel) double-helices
Stephen T Hyde1,2, Myfanwy E Evans3, Callum A R Metzke4
1School of Chemistry, University of Sydney, Camperdown, NSW 2006, Australia.
Abstract:
Many biomolecules and their synthetic counterparts preferentially assemble into double-helices with a preferred handedness and parallelism, such as all-antiparallel, right-handed double-helical polymorphs of DNA and RNA favored under ambient conditions by Watson-Crick duplexing. We analyze knots formed by double-helices which are exclusively all-parallel (or exclusively all-antiparallel) and all right-handed (or all left-handed) . Most simpler knot enantiomers are unrealizable. Among the nearly 500 distinct knot enantiomers with up to 10 crossings, fewer than 10% can be formed by such double-helices. Simplest designs for the folding of admissible knot enantiomers via duplexing of complementary base pairs in single-stranded RNA (or DNA) are enumerated for those knots.
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