Dear ALL:
Recently I am expressing one protein in BL21(DE3) and the protein undergoes N-terminal degradation.
I am trying to keep this crucial N-terminal tail on the protein, which has MRS at the first 3 positions.
Digging in to the literatures, I found the N-end rule, which tell that the proteins bearing N-terminal Arg or lys have much shorter half life.
I am not sure whether this is my problem. However, I want to found one E. coli mutant strain that lacks aat and is unable to degrade N-end rule substrates that bear N-terminal Arg or Lys.
Does anybody know such strains?
Thanks a lot and have a nice weekend,
Jerry,
