I have a pretty basic question.

I am refining a structure in which a drug has been covalently linked to a Cys of the protein.

I have generated the .cif fie for the ligand, but I don’t know how to tell the program that carbon C04 has to be covalently linked to the SG of the Cys. Is that sufficient to insert a LINK record in the pdb file? What is the correct syntax for that?

Thanks a lot for the feedback and sorry for the naive question,

ciao,

Sebastiano