Unfortunately, this is not something PyMOL can do at
present, and we were not able to come up with a workaround
In short, the code needs to be modified at
a fundamental level, but the cartoon generator in PyMOL is about as bad as
it gets: deeply nested code, 1-2 letter variables names, fragile pointers, and
almost all of it in one massive ~2,000 line C subroutine. RepCartoon.c is
one of those skeleton demons in the closet that must eventually be
challenged but will not be easily defeated...apologies.
This question has appeared a few times in the mailing
list yet I could not find any answer (maybe I missed
in cyclic structures there is a discontinuity at the last residue to the first
residue when displaying the cartoon representation. How do we make a
cyclic cartoon representation?