Hi,
I'd greatly appreciate advice on how to proceed with trying to solve and refine a structure with
nearly perfect merohedral twinning - or is this impossible? The SG is H3; most likely nmol is asu
is 4 from Matthews coefficient - but not sure about this.
Here are the twinning stats from phenix xtriage
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| Operator | type | R obs. | Britton alpha | H alpha | ML alpha |
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| h,-h-k,-l | M | 0.038 | 0.452 | 0.468 | 0.478 |
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The data is for a novel ligand complex for which we have previously solved structures with
different ligands in other space groups - the protein has two domains, and these may have moved
compared to other structures.
So what should I do? Try and solve by MR using detwinned structure factors? Can Refmac refine
the twin fraction, or should I refine against detwinned mtz file? Or ... should we look for additional
xtal forms, or try additives to see if we can reduce twinning?
Thanks !!!
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