Dear All, This is more a biochemical/biophysics question but since we need to complete our structural analysis with functional or biophysical data, I thought I would ask. We crystallized a protein as an MBP fusion and solved its structure. Based on previous knowledge we know that the small protein binds peptides. So we are now trying to measure binding of the protein to peptides labeled with a fluorophore using fluorescence anisotropy. Unfortunately the protein has to be used with its MBP still attached.
We have a resilient problem with the MBP carrier. It has some ‘residual’ fluorescence that interferes severely with our measurements (we are using tetramethyl rhodamine as fluorescent reporter). I was curious to know if anyone else had encountered this problem and figured out a solution. Any suggestion will be greatly appreciated. Many thanks in advance. Pascal Egea Assistant Professor of Biological Chemistry UCLA David Geffen School of Medicine