Abstract

The free energy change of the stacking process of DNA dimers has been investigated by potential of mean force (PMF) calculations. Two reaction coordinates were considered. One is the distance R between the glycosidic nitrogen atoms of the bases. The other is the pseudo dihedral angle X (N–Cl′–Cl′–N) . All 16 possible DNA dimers composed of the adenine, cytosine, guanine, or thymine bases in 5′ and 3′ positions were considered. From the free energy profiles, we observed good stacking for all DNA dimers and sequence-dependent stacking stability. This sequence dependence of the stacking free energy is in good agreement with the experimental results. We also observed that the PMF is the lowest at R = 4.0~4.4 Å and X = 20~40° for all the DNA dimers except for the dGpdA dimer. These values are close to those of the canonical B-DNA (4.4 Å and 29°).

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.