Hi Emily, Sure! One way is to just use the “bond” command. E.g., select the two atoms to be bonded (carbonyl C on last residue and N on first residue) and then enter command: bond sel <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/bond.html> Alternatively if you are in the Build Structure tool, the Adjust Bonds section has an option to add bond between selected atoms. You might have to change from “reasonable” to “all possible” if the bond would be longer than normal. <http://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/editing/editing.html#bond> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco

On Oct 8, 2018, at 9:15 AM, Emily Xu <emilyxu202@gmail.com> wrote:

Hello, Is there a way to join two ends of a peptide in Chimera? I am trying the create a peptide bond linking the C and N termini in a singular peptide to form a cyclotide. Is this possible in Chimera?