Hi,

I am new to Chimera, so perhaps someone could give me a hand.

I have used Robetta for predicting the structure of a protein I am interested in and it gave back models for different parts of the protein. I would like to join them, so I am trying to join two models by a C-N peptide bond. I have selected the corresponding atoms in the last amino acid in one of the proteins and in the first amino acid of the other protein I want to join. With both atoms selected I took the “Join Models” option in “Build Structure”  with the “C-N peptide bond” selected. And the “Apply” button does not activate. (See the screen shot attached)

I have gone through the manual and I do not see what I am missing or what I am doing wrong. Any help is welcome.

Thank you very much in advance.

Kind regards,

Miguel