Dear Acoot, if your metal is part of a protein crystal, your diffraction image still looks like the diffraction of a protein crystal. If you see salt spots, your crystal is salt, not protein.
However, what sometimes happens is that one has a badly diffracting protein crystals with some tiny salt crystals attached to it. In this case you might see some weak, almost nonexisting protein diffraction with strong salt spots. By looking at your crystal under the microscope, you may resolve this issue. Best, Herman Von: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] Im Auftrag von Acoot Brett Gesendet: Montag, 2. Dezember 2013 04:16 An: CCP4BB@JISCMAIL.AC.UK Betreff: [ccp4bb] A question on the diffrentiattion of the salt crystal and salt diffraction in the protein metal complex Dear All, Suppose I have a crystal hit from the protein-metal complex, with the possibility of that the hit is a salt crystal. When I diffract it by X-ray, I got some metal (or salt) diffraction without the protein diffraction (maybe due to too low protein resolution). Will you please tell me how to know whether my diffraction was from a salt crystal or from the diffraction of the metal in my protein-metal complex? I am looking forward to getting your reply. Cheers, Acoot
