Hi CCP4bb ,
Thanks for your suggestions... here is the summary of the
structure...
I am working in deletion and point mutants. I have a mutant (P61 resoln
3.1A) with partial twinning with twinning fraction 0.28. Wilson b-factor is
50. The data collected in the home source with normal exposure time. The
rmsd's of the refined structure is 0.0081 (bonds) and 1.38672 (angles).
Molprobity is score is 50 without any manual model building (just after the
refinement).
Since the structure is twinned new free R-flag has been chosen according to
CNS make_cv_twin.inp. The b-factor has been flattened to 30. Then
rigid-body_twin refinement followed by simulated annealing_twin is done
(heating the structure up to 5000K with different initial velocity trials).
The R and R free after this step is 18.35 and 27.22. Then i did
bgroup_twin refinement which gave me R and R free 17.06 25.63. Further
model building and refinement tend to reduce the R and Rfee upto 15 and 23.
I deleted some portion of the molecule and did refinement. But proper
density appeared after it.
Please help me out.
John
