Dear all I collected one dataset and processed it to 3.6 angstrom. my protein is quite small with only 14 kDa. It is estimated over ten molecules in one ASU based on Matthew coefficient calculation.
However, only ten molecules can be correctly placed with good fitting. I can observe extra Fo-Fc electron density maps there needed to be modelled. But Fo-Fc electron density maps are discontinuous. I tried to fix the ten molecules as the partial solution in phaser and search more molecules, either resulted in no solution or the newly added molecules didn't fit in the map after refinement. So I manually built the poly alanine chain in order to decrease the R factor. I built around 200 amino acids into the final model. but these poly alanine model can hardly be interpreted to remodel as my target protein because of the low resolution. Currently the ten molecules model has a Rwork/free as 0.33/0.36. The model with poly alanine chain has a Rwork/free as 0.30/0.34. I can already extract the useful information based on the well fitted ten molecules. And the fitting of the poly alanine models could just for better model refinement. Can I get some suggestions regarding this kind of issue, what's the general practise for such situation. Can I deposit the model with poly alanine fitted and labelled it unidentified to pdb? Thanks for any suggestions and replies. Best Regards Qiao Zhu ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1
