Investigation of the effects on the proteome composition of Escherichia coli producing a recombinant protein in the periplasm under non-optimized and optimized conditions

Recombinant proteins containing disulfide bonds, like antibody fragments, are usually produced in the periplasm of E. coli, because in this compartment of the E. coli cell the formation of disulfide bonds is catalyzed. A recombinant protein is targeted to the periplasm with the help of an N-terminally fused signal sequence, which is clipped off from the recombinant protein upon translocation across the cytoplasmic membrane. The single-chain variable antibody fragment BL1 N-terminally fused to the DsbA signal sequence was produced in the E. coli Lemo21(DE3) recombinant protein production strain at conditions non-optimal (0 µM L-rhamnose) and optimal (500 µM L-rhamnose) for the production of the scFv BL1 in the periplasm. Lemo21(DE3) cells not producing a recombinant protein were used as a reference.