Dear colleagues
I appreciate if anybody can help me in the following problem:
I used Lpp'-ompA system (developed by Georgio et al., 1996) for surface display of a bacterial metallothioneine fused to chitin binding domain and 6Xhis-tag (on the surface of E.coli BL21). The length of this passenger protein is approximately 15kDa. We did metal binding assay using whole cell and we measured adsorption using a solution of cadmium Cd(NO3)2 in Tris-Hcl pH7.0. But it didn't show any adsorption. Hydropathy plot showed the passenger proteins are hydrophile and also it didn't show any transmembrane domain. I would like to know why does not this protein show any adsorption?
I appreciate your help.
Best Wishes
Reza
