Dear Mahdi, Sorry, Chimera only includes changing the type of a nucleotide that is already in the DNA structure (command "swapna"), <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/swapna.html> ... or building a whole double helix from scratch, that is, without any starting structure (menu: Tools… Structure Editing… Build Structure, section: Start Structure, option: helical DNA/RNA) <http://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/editing/editing.ht...> I don't have much experience building DNA. Here are a couple web-servers, but I think they also only build entire structures from scratch: <http://structure.usc.edu/make-na/> <http://w3dna.rutgers.edu/index.php/rebuild> Elaine ---------- Elaine C. Meng, Ph.D. UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco On Jun 16, 2014, at 3:53 AM, Mehdi Bagherpour <mehdi.bpour@gmail.com> wrote:
Dear Chimera Users,
I want to add 3 base-pairs to two side of DNA. I tried more about that but I couldn't. Could some one any idea about doing that in chimera or another programs.
Best Regards, Mahdi