At 280nm absorbs Trp but Tyr and Phe (much less) as well. So your protein sample even without Trp will absorb. A mass spect experiment should show a presence of molecule with MW 507 (ATP) or MW 427 (ADP)
George **************************************************************************** ************ From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of Xinghua Qin Sent: Monday, June 04, 2012 7:52 AM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] How to know if ADP exists in the ATP-binding site of bacterial expressed proteins Deer CCP4ers, How to know if ADP exists in the ATP-binding site of bacterial expressed proteins? Check the UV spectrum at 280 nm is one way, but there is no Trp in my protein. Is there any other conveniet way to find out? Thanks in advance Best wishes Xinghua Qin -- Xinghua Qin State Key Laboratory of Plant Physiology and biochemistry College of Biological Sciences China Agricultural University No.2, Yuan Ming Yuan West Road Haidian District, Beijing, China 100193 Tel: +86-10-62732672 E-mail: <mailto:xhqin1...@gmail.com> xinghua...@126.com
