MAD Experiments in P1

[Chris Hosfield <chris@crystal.biochem.queensu.ca>]

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Dear All,

I am hoping to conduct a MAD experiment on a SeMet protein which 
crystallizes in both P21 and P1 space groups.  We have collected MAD data 
on the P21 form which has yielded decent, but not readily traceable maps.  
(The data collected were good, but not fantastic.)

We are hoping to use cross-crystal averaging techniques after performing 
a MAD experiment on the P1 form.  However, I am worried about collecting 
MAD data in P1, because even after a full 360 sweep at each wavelength, 
the redundancy of the anomalous data will be so low.  Has anybody 
collected MAD data in P1, and if so, do you have some practical 
suggestions?  Would it just be more useful to try to recollect more 
accurate and complete MAD data on the P21 form again??


Thanks for your help.


Chris 
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Chris Hosfield                     chris@crystal.biochem.queensu.ca
Graduate Student	   
Dep't of Biochemistry
Queen's University		   6cmh2@qlink.queensu.ca
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