Abstract: A process for the production of a naturally folded eukaryotic polypeptide containing two or several cysteines linked by disulfide bridges by a) culturing prokaryotic cells in which the said prokaryotic cells contain an expression vector which codes for the said polypeptide which contains a prokaryotic signal sequence at the N-terminus, b) secreting the polypeptide into the periplasm or the medium, c) cleaving the signal sequence and isolating the polypeptide from the periplasm or the medium, which is characterized in that a nucleic acid coding for a molecular chaperone is additionally expressed in the said prokaryotic cell and the chaperone is secreted into the periplasm, is suitable for the recombinant production of polypeptides in prokaryotes in a high yield.