Effect of Microenvironment on the Geometrical Structure of d(A) d(T) and d(G) d(C) DNA Mini-Helixes and the Dickerson Dodecamer: A Density Functional Theory Study.

We report a comprehensive quantum-chemical study on d(A)·d(T) and d(G)·d(C) DNA mini-helixes and the Dickerson dodecamer d[CGCGAATTCGCG]. The research was performed to model the evolution of the spatial structure of d(A)·d(T) and d(G) d(C) DNA mini-helixes all the way from vacuum to water bulk. The influence of external factors such as the presence of counterions and the extent of hydration was included.