From: Stefan Doerr (
Date: Thu Apr 21 2016 - 11:27:19 CDT

Hi, I was trying to remove a engineered residue from a protein when I fell
upon weird behaviour in atomselect.

If you try "resname PTR and backbone" you will notice that this leaves
behind 3 atoms, P, OP1 and OP2 which are obviously not backbone.

What is the reason for that?