I've seen some indications that cacodylate buffers can cause problems
for SAD/MAD experiments. My initial impression was that this was just
from the cacodylate leading to fluorescence spectra that shifts the
apparent peak to lower energy. We've solved a number of SAD structures
(Br) in crystals grown in cacodylate buffer, but only recently have we
run into a case that appears to have decent anomalous signal, but has
proved difficult to find a reasonable solution. Is there some other
effect that cacodylate might be having, or is this likely just the case
of poor energy choice and/or poorly ordered scatterers?
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