S97: A case study comparing recombinant human protein expression and purification using Clean Genome E. coli® and BL21(DE3)

Scarab Genomics has generated a series of multiple deletion strains (MDS) of E. coli K-12 that lack numerous non-essential genes, mobile DNA elements (insertion sequences and prophages), and potential virulence factors.  The MDS platform is the only commercial “clean-genome” host expression technology available for cGMP manufacture of protein and pDNA biologics.  ScarabXpress™ is a specialized MDS for protein expression applications.  This host carries an integrated T7 RNA polymerase gene under the control of a modified lac promoter and operator.  The host was evaluated in a pET based expression study comparing BL21(DE3) and MDS for the expression and purification of a 83-kDa cytoplasmic protein of human origin.  As compared to BL21(DE3), ScarabXpress™ demonstrated superior performance, with tighter regulatory control, more stable protein production, increased yield and improved purification results at bench scale.