Daniel, You'll probably have to monitor pH changes through size changes of your protein, provided the structural changes will indeed cause size changes.
You said "easy", so that probably rules out Small-Angle X-Ray Scattering (SAXS), but that would be the highest-resolution method. You can try static and dynamic light scattering, analytical ultracentrifugation and fluorescence anisotropy. If you are really lucky, size exclusion chromatography might work too. And then there are the "difficult" ways... MM On Dec 6, 2010, at 11:59 AM, Daniel Jin wrote: > Dear CCP4 colleagues, > > We have a protein that is composed of two domains connected by a short > peptide linker. We have some indirect evidence showing that the two domains > may somehow move against each other when exposed to different pH. It is > unlikely to have any obvious secondary structure change since each domain > behaves like a rigid body. I am wondering whether there is any “easy” way, > biochemically or biophysically, to monitor the conformational changes in > solution. Many thanks. > > As far as I know most of the pH sensing stories are linked to histidine > residue. Can you point me to any references that show a different pH sensing > mechanism (other than His)? Thanks. > > Best, > Daniel > ----------------------------------------------------------------------- Mischa Machius, PhD Director, Center for Structural Biology Assoc. Professor, Dept. of Pharmacology Member, Lineberger Comprehensive Cancer Center University of North Carolina 4079 Genetic Medicine CB#7365 120 Mason Farm Road Chapel Hill, NC 27599-7365, U.S.A. tel: +1-919-843-4485 fax: +1-919-966-5640 email: mach...@unc.edu
