I've found the scala CC-anom significantly underestimates the anomalous
signal, relative to e.g. xprep. I don't know why that is, but the
latter seems to agree with what shelxd is happy with.
Cheers
phx
On 29/06/2010 10:35, Graeme Winter wrote:
Hi Murugan,
One useful indicator of raw anomalous signal is the ANOMPLOT graph
from Scala - this shows the differences between reflections compared
with the expected differences. If the gradient of the plot is 1
there's no more differences that you would expect. If the gradient is
more than one there is (or may be.) - also check out the merging
statistics as a function of batch, if there's significant radiation
damage this may mess things up.
Scala writes out the gradient (assuming you told it anomalous on) in the summary
Another rule-of-thumb is the resolution limit where cc-anom is> 0.5.
The most practical indicator of the anomalous signal is of course the
success or failure of the subsequent phasing :o)
Best wishes,
Graeme
On 29 June 2010 10:05, Vandu Murugan<wandumuru...@gmail.com> wrote:
Dear all,
I have collected a 2.7 angstrom home source data with Cu-Kalpha source
for a protein with 6 cysteines, with a multiplicity of around 23. I need to
know, is there any significant anamolous signal present in the data set,
since there is no good model for my protein. Can any one tell, which
program to run, and what parameter to see? Thanks in advance.
cheers,
Murugan
