Without knowing the resolution, you could try to use TLS refinement (if you haven't done it already) and see if the maps improve and allow you to build more/better. If the resolution is reasonable and you can not lower the R & Rfree you should check whether twinning is possible. It is common AFAIK that in twin cases the R-factors get stuck above 30 %.
~L~ _______________________________________ Lari Lehtiö Structural Genomics Consortium Medical Biochemistry & Biophysics Dept. Karolinska Institute Stockholm, Sweden _______________________________________ ----- Original Message ----- From: Yongchao Li <[EMAIL PROTECTED]> Date: Tuesday, January 8, 2008 1:51 am Subject: [ccp4bb] How to refine large moleculars? To: CCP4BB@JISCMAIL.AC.UK > I have a large molecule to refine.There are about three thousand > residues in one asymmetric unit. > Except for the lack of electron densities in several places, where > the > loops have been deleted, the rest parts fits well with density. But > the R free and R work are all beyond 0.30 (R free = 0.35, R work = > 0.30).I don't know how to reduce them. > Can anyone give me some ideas? > > Thank you! > > > > --------------------------------- > Looking for last minute shopping deals? Find them fast with Yahoo! Search.
