Dear Armando, Is 1.9Å really the diffraction limit of your crystals, or do they diffract further and is 1.9Å just a convenient resolution cutoff? In the latter case you might be looking at truncation effects. Best, Herman
-----Ursprüngliche Nachricht----- Von: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] Im Auftrag von Armando Albert Gesendet: Freitag, 18. Juli 2014 18:04 An: CCP4BB@JISCMAIL.AC.UK Betreff: [ccp4bb] Negative electron density in the Fo-Fc map at the binding site Dear all, I am screening a small library of ligands against my protein crystals. Following a soaking with different ligands, I collect datasets to 1.9A resolution and refine them against an empty model without any problem. What is the meaning of a rather large negative electron density in the Fo-Fc map at the binding site?. Could it be related to an incorrect bulk solvent model? Thank you in advance Armando
