COEXPRESSION OF HUMAN PROTEIN DISULFIDE-ISOMERASE (PDI) CAN INCREASE THE YIELD OF AN ANTIBODY FAB' FRAGMENT EXPRESSED IN ESCHERICHIA-COLI

Secretion to the periplasm of Escherichia coli enables production of m any eukaryotic extracellular proteins in a soluble form. The complex d isulphide bond arrangement of such proteins is probably a major factor in determining the low yield of correctly folded product observed in many cases. Here we show that co-expression of human protein disulphid e isomerase increased the yield of a monoclonal antibody Fab' fragment in the periplasm of E. coli.