Depending on what you’re doing, you might want to try ChimeraX instead. It has much better performance on large systems.

<http://www.rbvi.ucsf.edu/chimerax/docs/user/advantages.html>

On my laptop, “open 5iv5” in ChimeraX takes only a few seconds to download the file and then show the structure:

The ChimeraX download page lists some of the major features that are still missing:

<http://www.rbvi.ucsf.edu/chimerax/download.html>

If you really only wanted that chain, however, you could just download the entire structure file directly from the PDB website (not involving Chimera), text-edit the file to only the chain of interest, and then open it in Chimera.

I hope this helps,

Elaine

On Feb 11, 2018, at 6:21 AM, Healey, Joe <J.R.J.Healey@warwick.ac.uk> wrote:

Hi again Chimera team,
I need to download a chain from an enormous macromolecular complex as it's so large it actually crashes Chimera!
Is it possible to do this directly in chimera somehow (downloading just that specific chain or chains? The fetch dialogue doesn't seem to like the typical underscore notation (e.g. 5IV5_BB )
Thanks
Joe