Checking whether degradation of the fusions with OmpA is caused by Lon and OmpT proteases (present in TOP10)

Piotr

Test was conducted in E.coli Rosetta strain expressing OmpA_omega_ΔA_alpha (with and without induction) and OmpA_ΔA_alpha.

1. Spinning.
2. Suspending.
3. Adding the lysis buffer.
4. Boiling.
5. Putting into poliacrylamide gel.
6. Transfer onto nitrocellulose.
7. Blocking.
8. Anti-A antibody binding.
9. Washing.
10. Anti-rabbit antibody binding.
11. Developing with BCIP and NBT (Fig. 1.).

We didn't observe differences in expression and degradation in Rosettas nor in TOP10. Therefore we suppose that degradation of the fusions is caused by factor other than Lon and OmpT proteases.

Purification of proteins: Z-alpha and Z-omega

Emilia

100 ml of medium inoculated with overnight culture, then used as inoculum for 1 l culture in presence of ampicillin, kanamycin and IPTG (according to protocol).