Dear crystallographers,
I hope someone could give me a hint to solve this problem.
I have collected five datasets from the same protein and all of them,
including the highest resolution data set (1.6 angstrons), display at the
active site of the enzyme a very clear electron density with boundaries
well defined. The problem is that I have already tried to fit all kinds of
molecules present in the purification and crystallization conditions and
none of them fit well into the density.
Here are my questions: Is there any program available that could take a
small volume of the electron density map (obviously the unidentified
electron density ligand) and try to fit a list of known compounds (a list
that I do not have, by the way) for potential ligands? Or, is there any
website or program that could give me a list of compounds based only in
the backbone of the ligand I could sketch from the density (by backbone I
mean the plane shape of the compound – I do not know its atom
composition)?
I hope someone could help.
Thanks
Ronaldo.
|