[gmx-users] Residue name length

András Ferenc WACHA wacha.andras at ttk.mta.hu
Sat Feb 2 14:22:51 CET 2019

Dear Gromacs users (or developers),

does anyone know if there is a limitation on the maximum length of
residue names? The reason I'm asking this is that I am trying to build
residue topologies for disubstituted beta-amino acids with proteinogenic
sidechains. My current nomenclature covers all such beta-amino acids in
at most 7 characters (including the most obscure ones). First of all: is
there an input coordinate format which supports this? .gro and .g96
support at most 5 characters, .pdb only 3. Secondly, if there would be
such a format, can the MD code choke on long residue names due to some
hard-wired limit in the code?

If the limit is five, what other possibilities do I have? Are residue
names case sensitive, for instance (e.g. B2a and B2A are considered the
same or not)?

Thank you for your help,


András Ferenc Wacha, PhD
research fellow, CREDO instrument responsible

Biological Nanochemistry Research Group

Institute of Materials and Environmental Chemistry
Research Centre for Natural Sciences
Hungarian Academy of Sciences (RCNS HAS)
Magyar tudósok körútja 2.
H-1117 Budapest, Hungary
Phone: +36-1-382-6427
Web: http://bionano.ttk.mta.hu, 
CREDO SAXS instrument: http://credo.ttk.mta.hu

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