Hello, a couple of thoughts.
If your best dataset has a twinning fraction of 40% (i.e. almost 50:50 ;-?) and
the twin operator corresponds to a 2-fold rotation parallel to the z-axis, is
it definitely trigonal, rather than hexagonal? The 2-fold NCS operator that you
found for the d3 domains, is
Hmmm -
not much help, but MR can work with twinned data ..
What's the sequence match between your models and your protein? And do you
expect them to form a dimer?
Presumably you found the d3:d3 dimer using MR? I would be a bit worried
that the twinning could mislead a dimer search - are the two d3
