Production and purification of a recombinant protease produced from Escherichia coli

The present investigation involves the production and purification of an SDS-resistant alkaline serine protease (ProA) from Vibrio alginolyticus . The protease has application in household laundry detergent formulations and as a potential alternative to proteinase K.; The protease was produced recombinantly in Escherichia coli on a 2 liter scale. Cell concentration monitored by optical density increased steadily for 12 hours followed by a continuous fall till the end of a 24 hour growth cycle. The ProA concentration in the fermentation broth started increasing from background values after 12 hours indicating the increase in ProA level mainly due to cell lysis.; Purification protocols that were developed used total protein recovery and protease purity as the performance evaluation criteria. A recovery of ∼80% ProA activity, with 10–15 fold purification, was achieved with a protocol consisting of cell removal, followed by ammonium sulfate mediated bulk precipitation and benzamidine-sepharose-based affinity chromatography, or alternatively diethylaminoethyl-based ion exchange chromatography.