Summary of Section 2
Nucleic acids are intrinsically highly flexible molecules.
The chemical properties of nucleic acid components are primary determinants in structure formation.
The formation of nucleic acid structures is driven by base pairing and stacking interactions between the hydrophobic bases. In DNA, these interactions drive the formation of the double helix, whose structure is maintained under torsional stress by twisting. RNA secondary structure is driven by maximal base-pairing rules.
The five common bases found in nucleic acids can be modified after synthesis.
Base pairing is exploited in the laboratory in many techniques that utilise strand annealing (hybridisation) between a labelled nucleic acid and a target polynucleotide.