Dear BB,
I am attempting molecular replacement with a 2.8A data set from crystals of a coiled coil of about 150 residues.
Probably p21212 but maybe p2221.
So far, Phaser, MolRep, Amore, Mr Bump, have not provided a good solution as judged by Z-scores, CCs, Rfactors, and whether there is any density outside the model (there should be - I'm using a slightly shorter model to search with).
One possible problem is that the coiled coil may not be straight. It may have a slight curve to it.
I have used models from the PDB that are straight or slightly curved, so far with no success.
I have tried a few different resolution cutoffs too.
I have tried single helix chains or dimeric coiled coils.
Is there anything special about MR with coiled coils?
Can anybody provide any tips/hints on MR with coiled coils??
Thanks
Ed
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