Just a short erratum: the PDB limit is actually 62 chains (all upper and lower case letters plus digits).

—Eric

On Apr 2, 2018, at 2:51 PM, Eric Pettersen pett@cgl.ucsf.edu wrote:

Hi John, The PDB format only supports single-character chain IDs (one of the reasons for mmCIF format), so it is impossible to save structures with more than 36 chains in PDB format without losing chain information. A semi-workaround is to:

1. In ChimeraX: split the structure into multiple structures, one per chain (“split #1”)
2. Save those models into a multi-MODEL PDB file (“save ~/rib.pdb models #1”)
3. Read them into Chimera.
4. If there are <= 36 models, combine them into a single model (“combine” button of the Model Panel), otherwise you just have to work with them as separate models.

—Eric

Eric Pettersen UCSF Computer Graphics Lab

...

On Apr 2, 2018, at 2:29 PM, John Mercer, Ph.D. <jmercer@duke.edu mailto:jmercer@duke.edu> wrote:

Hi Elaine,

I load a ribosome mmcif file in ChimeraX and save it at as a PDB file. It loads and works fine in Chimera but all the chain identifiers have disappeared. Is there away to save a PDB file from ChimeraX that retains the identifiers? I am wanting to use the larger set of tools in Chimera when only mmcif files are available.

Best, -John _______________________________________________ Chimera-users mailing list: Chimera-users@cgl.ucsf.edu mailto:Chimera-users@cgl.ucsf.edu Manage subscription: http://www.rbvi.ucsf.edu/mailman/listinfo/chimera-users http://www.rbvi.ucsf.edu/mailman/listinfo/chimera-users