here is some basic information about the protein:

1. This protein is as big as 90KD.

2. The productivity of the protein is very low, and the homogeneity of the protein is not good. Most of the proteins come out of the column at void volumn, and the rest of the proteins forms 3-4 peaks, and each of them features low peak height.

3. I have already tried different truncates of the protein and homologous proteins from other species, up to now the protein on my hand is the best of them.

4. I have stocks of the following detergents:n-Octyl-b-D, n-Decyl-b-D, FOS-Choline-12, n-Dodecyl-b-D, Cymal-5, CHAPS, Tween20, Triton-X100.

 

my question is:

1. would you please recommend some other detergents to try? 

2. should I try different concentration of the detergent and how? right now I just tried the concentration equals the CMC, some of the detergents do improve the homogeneity of the protein, however, once I concentrate the protein for crystallization, the detergent get concentrated too, and as you know that is very bad for crystallization.

3. would you please recommend me some literature to resort to (about the same situation as mine or about the use of detergents)?

4. any other suggestions or comments about how to improve the quality of the protein.

 

Your suggestions and comments will help me a lot and will be highly appreciated.

 

Many thanks to all of you!

 

Bei