Hi Peter, How do you know you have crystallized the complex? Perhaps MR is not working because your crystals only contain the small protein.
good luck, Eric
Hi all, I have a small complex, one component is 13 kDa with structure available and the other is 7 kDa, which could not be able to grew crystals after lots of efforts. It grew crystals after methylation and diffracted to 2.3 A, however, I could not be able to solve the structure using the structure of the big component as a template for molecular replacement, and heavy atoms soaking was not successful. I plan to do selenomethionine expression next. Does the methylation change protein structures a lot? otherwise, why does molecular replacement not work? I would much appreciate any idea and suggestions how to solve the structure using the data and the template avaliable. Many thanks for your help. Peter ____________________________________________________________________________ Date: Tue, 24 Nov 2009 18:27:49 +0100 From: jan...@googlemail.com Subject: [ccp4bb] Methylation of macromolecular complexes To: CCP4BB@JISCMAIL.AC.UK Hi all, I have a question regarding the methylation of macromolecular complexes. Is there any report where a macromolecular complex has been successfully methylated and later on crystallized. Is methylation a method of choice to chemically modify macromolecular complexes where the entropical contributions by lysines might be a cause for not obtaining crystals, or is there any other better ways? thanks, Jan Rash ____________________________________________________________________________ Keep your friends updated— even when you’re not signed in.
