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Hi, Dear all, Firstly ,I'd like to thank all the people for their kind help, especially Miguel, Bernie ,Mark, Moody, Eleanor, Eaton , Peter and lots of others ....Without your help, I wouldn't make it this far. Secondly, I'd like to share some of the experiences. We had a hard time trying to do MR for this protein. The data was indexed very well in R32, and we can only find two molecules,we just couldn't find the other.We stocked for a long time, not until recently, we figured it's actually a C2 space group. But when we tried to search with one monomer, we couldn't find the solution either because the signal is really low.So we search by those two molecules ( from R32 ), and bingo, we found 6 molecules.So on and so forth, now we are able to find 9 molecules and we believe that's all.Three molecules are bundled together and form three trimers and these three trimers are 3-fold symmetry related.We were excited and went for the next step refining...But after rigid body refinement, the Rfree is still very high , 44%.We calculated the map and looks like density around one loop region is incomplete.I was told that I should give this up, because there is no way to build the model because the density is missing. But I was just wondering if there are any better ways to do refinement, is there any way that could possibly determine the structure.The data is 2.1A,but my protein is really small, 10kD, looks like the packing is really not that great.We are now using CNS to do the refinement. Any suggestions would be highly appreciated. Thanks. Jenny