> This can be done, in a way. In proteins we have an unknown amino acid. Of
> course all amino acids have the same 'linkage positions', so that is
> easier. You could add one or more unknown sugars. There are problems,
> though.
>
> We can not change the composition of an existing molecule.
I am hoping that the data model can evolve so that molecules can be edited
in the API. This might be tricky to achieve though. It seems to be a
reasonably common occurrence that Analysis users don't know their exact
sequence (e.g. from inaccuracies in DNA seq or unexpected constructs)
until part way through the assignment procedure.
I guess this would also be an issue for sample management where molecules
become better resolved, and generally it might be nice to record
intermediate molecular information, just as we can record intermeditate
NMR assignment information. NMR can be used to determine what a molecule
is.
Hopefully it would be less work to substitute or add the occasional
molResidue, rather than repace an entire molecule and all of its links,
especially considering that they could span lots of parts of the model.
T.
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Dr Tim Stevens Email: [log in to unmask]
Department of Biochemistry [log in to unmask]
University of Cambridge Phone: +44 1223 766018 (office)
80 Tennis Court Road +44 7816 338275 (mobile)
Old Addenbrooke's Site +44 1223 364613 (home)
Cambridge CB2 1GA WWWeb: http://www.bio.cam.ac.uk/~tjs23
United Kingdom http://www.pantonia.co.uk
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