 |
 |
Dear All, We are trying to solve a protein structure by molecular replacement. The protein crystal has unit cell dimensions of a=50 b=51 c=252, alpha=90 beta=90.4 gamma=90. We processed the data both as P21 (two molecules in A. U.) and P21212 (one molecule in A. U.). We have built a model based on sequence homology. It is very interesting that we still found one molecule using P21 data, reasonably GOOD density although the model is about 60 A wide and 82 A long (just refine this one molecule using P21 data, the Overall R factor=0.4731, Overall figure of merit=0.4939, the protein molecule seems have no symmetry by itself). We can not find any solution using P21212. The protein seems have three domains based on our model. We tried to using only one of the domains. The results were similar. Any suggestions as to what else is possibly wrong except that we have not found the correct solution? Thanks in advance, Chunmin