> > > Chi2 is unusually high at lower resolution (Chi2 is >3 from 3.5A as
> shown
> > > below) and there is a relatively high percentage of rejections (>1.5 %).
> > >
> >
>
> Chi^2 in Scalepack *must* be adjusted by changing the expected errors to be
> about 1.
> Until then, I would not reject
Hello -
Sorry if some of my suggestions are redundant since I jumped in late
in this thread.
A couple of additional comments after struggling with a similar albeit
not identical case.
With a pseudo translation vector like that the SG could be any of
the 8
orthorhombic SGs; P222 P21 22
With a pseudo translation vector like that the SG could be any of the 8
orthorhombic SGs; P222 P21 22 P21212 P212121 P2 21 2 P2 21 21 P 2 2 21
Test them all, and see if any give a dect solution..
Eleanor
Alison Li wrote:
We recently collected a complete 2.5A MAD dataset. However, finding a
sol
ubject: [ccp4bb] difficult MAD dataset
We recently collected a complete 2.5A MAD dataset. However, finding a
solution has not been as straightfoward for reasons unclear to us. We
would
be grateful for any helpful advice or suggestions.
The thin plate shaped crystal was grown from a relatively sma
Alison, Given:
> There is a pseudo-translation with 55 % peak at a fractional
> coordinate of 0.5, 0.5, 0.48.
I don't think you can be certain about:
> Systematic absences along a and b axis were observed thus the
> dataset was scaled in P21212 space group.
Try testing all eight possible Orth
Hi Alison,
You wrote:
We recently collected a complete 2.5A MAD dataset. However, finding a
solution has not been as straightfoward for reasons unclear to us.
Is there radiation damage in one or more of the later sets?
Did you try 1 or 1.5 wavelength? (See Dauter, /Acta Cryst./ (2002).
D*58*,
Hi Allison,
How sure are you of your spacegroup? Have you tried P212121? It is a much more common
spacegroup. How did you look for your systematic absences? It is possible that the
systematic absences are also present along the third axis even though all the reflections
have not been measu
x: (630)252-0667
rsanishv...@anl.gov
> -Original Message-
> From: CCP4 bulletin board [mailto:ccp...@jiscmail.ac.uk] On Behalf Of
> Alison Li
> Sent: Thursday, January 29, 2009 3:38 PM
> To: CCP4BB@JISCMAIL.AC.UK
> Subject: [ccp4bb] difficult MAD dataset
>
> We recent
We recently collected a complete 2.5A MAD dataset. However, finding a
solution has not been as straightfoward for reasons unclear to us. We would
be grateful for any helpful advice or suggestions.
The thin plate shaped crystal was grown from a relatively small protein (90
residues).
The crysta
