I'm trying to solve a structure by MR using Phenix,reso. 2.69A,sg I121(imosflm), but I'm taking upto 2.9A data and sg P1 which shows 0.49 twinning(h,h-k,h-l).I've got 3monomers/asu & the R-factor/R-free is 28.97/36.34 at 2.9 using twin law,xyz-refinement,individual B factors. Now R-free becomes static,with almost a minor change in decimal place & clashscore is increasing in every steps,when I'm trying to rectify the residues listed in Ramachandran outliers/Rotamers outliers...etc. the C-N bond get collapsed/the whole residue get detached/the geometry worsen.The starting model requires atleast 20% side-chain mutation but there's almost no density for the left out large side chains.Please suggest how to overcome this problem.Thanks in advance.
Regards,
Ms.Seema Nath
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