[ccp4bb]: substrate soaking into crystals

["N.Manoj" <nm77@cornell.edu>]

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Dear all,
           I am trying to get cocrystals with ATP bound in the active
site.  But the electron density maps show no evidence of ATP binding. I
have ~200mM ammonium sulphate, PEG and 4mM ATP in the crystallization
conditions and most probably ammonium sulphate competes with the ATP,
preventing its binding.
Does anyone know of a case where the ammonium sulphate has been
exchanged or replaced from the crystals by soaking etc and found
competing substrates being bound after that?
Thanks in advance

manoj