Dear All, Thank you all for reply. We have checked the data for twinning. Our protein is 360 residues around 40 kDa protein. We have tried TLS refinement. chain A and B don't superimpose well with chain C and D. (A and B chains also share slight difference ) Since we don't have proper density for *some regions* chain C and D, we are not sure whether these chain have similar or different conformations. We tried anisotropy correction and the model refined a bit.
On Wed, Jan 25, 2017 at 10:32 AM, Debanu <debanu....@gmail.com> wrote: > Hi Pooja, > > Are you positive you have the correct space group and there are no other > issues like twinning, etc? > > If sure, did you define NCS groups in refinement? TLS refinement? Try > different refinement programs? > > How big is the molecule? Was it solved by MR or experimental phasing? > > You can try superimposing A/B on C/D and refinement with tight NCS then > adjust NCS restraints during model adjustments based on local differences > or also see if phenix autobuild helps. > > Best, > Debanu > -- > Debanu Das > Accelero Biostructures > > > On Jan 24, 2017, at 8:42 PM, Pooja Kesari <pkesar...@gmail.com> wrote: > > Dear All, > > I have a 2.6 A resolution structure having four chains in an asymmetric > unit. > The chain A and B have density for almost all residues however we don't > have proper residue density in chain C and D.What can be tried to build > chain C and D ? > > > > Many Thanks > Pooja > > -- Thanks & Regards, Pooja Kesari Research Scholar Department Of Biotechnology Indian Institute of Technology Roorkee INDIA
