Edman – degradation limits and problems

 

1.               Side reaction with PITC

                  e.g. primary amine, oxidants,..

2.               Shift in coupling pH

                  e.g. buffer salts,..

3.               Neutralizing of TFA (TFA)

                  e.g. buffer salts,..

4.               Reaction with amino terminus

                  e.g. cyanate, aldehyde, urea,..

5.               UV – absorbing compounds

                  e.g. formed from amines

 

Optimization:

1.               No TRIS, glycine.. as buffer

2.               No saccharose, glucose,..

3.              Detergents contain aldehydes, (no Triton X-100, Tween,..)

4.               SDS - inhibits Edman - degradation