Patent ID: 8426168

Claim:
A process for the preparation of a recombinant polypeptide, consisting essentially of the steps of a) fermenting a prokaryotic host cell in a fermentation medium, the host cell comprising a periplasm and being transformed with a recombinant expression system capable of effecting secretion of the polypeptide into the periplasm of the host cell, wherein the fermentation is performed in the fermentation medium under conditions such that polypeptide is secreted into the periplasm of the host cell, b) interrupting further processing of the host cell by maintaining, retaining, keeping, or storing the fermentation harvest broth under non-lethal conditions at a temperature of from about 4° C. to about 25° C. at a pH of from about 4 to about 10 and for a time ranging from at least 1 hour to about 72 hours so as to ensure that the integrity of polypeptide secreted into the cell periplasm in the cell in the fermentation harvest broth is maintained while avoiding any further fermentation of the medium; c) concentrating the fermentation harvest broth by centrifugation or micro filtration either prior to or after interruption of the further processing in step b), and d) recovering polypeptide from cell periplasm in the concentrated fermentation harvest broth following interruption of further processing of the fermentation harvest broth in step b), wherein the yield of polypeptide recovered from the periplasm is increased compared to the polypeptide yield of processes in which further processing is not interrupted.