Effect of DPC concentration on IDP NMR
 

I am working on a protein which has an important function in regulation of Lipid metabolisism, which is found to be functioning in multiple other ways and is beleieved to be an IDP. We are trying to find the structure of this molecule in the presence of DPC micelles. Recently we have got some curious results 1. DPC concentration (actually the molar ratio with the protein) has a huge impact on what you see in the spectra 2. whether you use protonated or deuterated DPC it does not matter so much. Any insights on this?

That does not strike me at all as surprising. You may see changes in the structure of the protein depending on the extent of association with lipid, the extent of self-association, or the adoption of secondary structure. Without more info about your system it is difficult to say which is the most important source of the changes you see.