This is a coot/refmac problem, but mainly coot I think, and I didn't want to 
cross-post.

I'm deeply confused about atom & residue naming for nucleic acids. 

There are several groups here working with RNA, and I recently broke coot for 
them, by installing the latest "experimental" refmac, and more particularly 
it's new dictionaries, into directory $CLIBD_MON. These dictionaries use what I 
believe are the most recent naming conventions, ie RNA residue type are A, G, 
U, C (not Ar etc), and DNA residues are DA, DG, DT, DC. Also ribose atoms are 
named with "'" rather than with ""*".

Thus AFAICS there are two name sets here

1. "Old" names: residue names Ar, Gr, Ur, Cr for RNA and * in the ribose atom 
names.
2. "New" names: residue names A, G, U, C for RNA and ' in the ribose atom names.

The coot script (in COOT/bin/coot) by default picks up dictionaries from 
$CLIBD_MON (with new names now), unless I uncomment the line

COOT_REFMAC_LIB_DIR=$COOT_PREFIX/share/coot/lib
(and the corresponding EXPORT command)

in which case it uses Coot dictionaries (in COOT/share/coot/lib/data/monomers), 
which use old names


There are then the following cases:

1) if I leave Coot pointed at the (new) refmac dictionaries, then 
regularisation fails, both with files with old names (since they don't match 
the dictionaries) and with a file which I've edited to the new name convention 
(since Coot automatically and inconveniently converts a new-name file to old 
names)

2) if I point Coot to its own dictionaries, then files with both old & new name 
conventions work, but new names are converted to old names, so output files 
will be like that

Refmac with the new dictionaries seems to be able to read RNA files with either 
new or old naming, and preserve the naming scheme.


So my question is: how do I set up a system which will work with Coot, Refmac, 
and preferably Molprobity and Phenix too? What are we _supposed_ to do?

Phil


PS:

1)  Are the atom naming conventions described anywhere in an intelligible 
fashion? I found it hard to find things on the RSCB web site, particularly for 
hydrogen atom names

2) the "new" dictionaries from the Refmac site seem to have the old (v2?) 
hydrogen names for amino-acids, at least as far as I can tell from the hydrogen 
names given by Molprobity which I believe are in the "new" v3 convention (see 
PS point 1)

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