Dear Florian,
ARP/wARP supports 65 space groups where proteins crystallise and it
indeed uses the Hermann-Mauguin convention as given in the International
Tables. The space group P22121 (number 3018 in the CCP4 symop.lib) is
not supported by ARP/wARP. The standard for it would be number 18,
P21212. The easiest is to re-index your data.
The error message 'cannot extract asymmetric unit limits' should then
also disappear.
Victor
PS. Actually, Tassos has already replied while I was typing this message.
Florian Schmitzberger wrote:
Dear All,
I am trying to build a molecular replacement model in arp/warp in space group P22121.
Refmac alone seems to be fine with refining the model in P22121; but arp/warp fails, as far
as I can see at the first Refmac refinement stage. In the log-file it says "this space group is
not supported".
I am wondering whether arp/warp needs the Hermann-Mauguin convention space group
P21212. I suppose I will need to reindex in P21212 in order to use arp/warp? (the diffraction
data were indexed in XDS, scaled in SCALA, and then run through CAD to change the space
group from P222 to P22121). I am using arp/warp via the ccp4i interface.
Also, arp/warp gives the following message when I load the mtz file "cannot extract
arp/warp asymmetric unit limits, the job will fail if run." (i did run arp/warp successfully with
other mtz-files).
Thank you in advance for any comments!
Florian
