I had some crystals that grew with "no precipitant" in 10 - 20 min.
as well. These were very ugly clusters. The real pricipitant was
manganese present at 25mM, which formed a lattice contact. I reduced
both the metal concentration and the protein concentration to make
better crystals. I also found it could be useful to start from a
more dilute starting point, i.e. 4ul well + 4ul protein + 4ul water
to make the drop.
Joe Krahn
