Membrane and Adsorption Processes in the Purification of the Human Pancreatic Secretory Trypsin Inhibitor (hPSTI)

Abstract

AbstractThis paper describes a process for the purification of hPSTI from a recombinant Escherichia coli. The E. coli strain carries the hPSTI‐gene on a multicopy plasmid with the ompA‐leader‐sequence, which results in the secretion of hPSTI into the medium. The separation of the cells and the prepurification were carried out either by ultrafiltration alone, by a combination of cross‐flow microfiltration and ultrafiltration, or by a combination of flocculation and ultrafiltration. The ultrafiltration was followed by three chromatographic steps. After the final purification step hPSTI was homogeneous as judged by SDS‐PAGE (silver stain). Process scale up should be relatively simple.