Hi Zhen,
This probably means that the bond is part of a large cycle of bonds created by cross-chain linkages such as disulphide bonds.  You would have to break one or more of those linkages in order to rotate the bond.

--Eric

Eric Pettersen
UCSF Computer Graphics Lab


On Oct 15, 2025, at 10:54 AM, Gong, Zhen via ChimeraX-users <chimerax-users@cgl.ucsf.edu> wrote:

Dear ChimeraX team,
 
I was trying to use ChimeraX to change the phi/psi angles of a residue in the loop region but encoured this error: ILE 411 N ↔ CA is part of a ring/cycle and cannot be rotated. There is no ring/cycle in ILE411 or neibouring residues: ASN 410 or THR 412.
 
I tried ChimeraX daily (version 1.10.dev202504260127 (2025-04-26) and ChimeraX 1.10.1 but the same error happened. I am wondering if it is possible to change the phi/psi angles with ChimeraX. Thank you.
 
Best,
Zhen
_______________________________________________
ChimeraX-users mailing list -- chimerax-users@cgl.ucsf.edu
To unsubscribe send an email to chimerax-users-leave@cgl.ucsf.edu
Archives: https://mail.cgl.ucsf.edu/mailman/archives/list/chimerax-users@cgl.ucsf.edu/