Laboratory-scale permeabilization of Escherichia coli cells for recovery of a small recombinant protein – Staphylokinase

Abstract

The recovery of recombinant proteins includes a purification process that has to be compressed to a minimum of steps in order to get high yields with a low cost expenditure. A selective liberation of recombinant proteins by cell permeabilization leads to both a high product purity just in the beginning of the recovery process and to a simplification of the cell residue separation compared to the mechanical cell disruption. In case of the purification of the bacterial plasminogen activator Staphylokinase from E. coli cells, yields of 82% with a purity of 46% were attained by utilization of permeabilization by biomass freezing, resuspension in a Tris/EDTA-buffer and following micro-diafiltration. A recovery process without interruption (freezing) is possible due to the addition of guanidine-HCl and Triton X100 to the buffer. These methods were developed on a laboratory-scale.