CRM197 is a nontoxic mutant of diphtheria toxin containing a single amino-acid substitution of glutamic acid for glycine. CRM197 is a well-characterized carrier protein used in a number of approved and highly successful conjugate vaccines including Pfizer’s Prevnar® pneumococcal vaccine, a multibillion-dollar franchise; HibTiter® (Haemophilus influenzae b) vaccine, and Novartis’ Menveo® meningococcal vaccine. Traditionally, CRM197 is produced by fermentation of a Corynebacterium diphtheriae C7 (β197) tox (–) strain, which secretes it into the culture supernatant. It is then recovered after…

    Figure 1: ()   The PfÄ“nex Expression Technologyâ„¢ platform is a very powerful protein expression technology based on the microorganism, Pseudomonas fluorescens. The Pfenex platform can deliver a robust production strain with unprecedented speed and a success rate that transcends legacy production hosts. Traditional recombinant protein expression hosts such as E. coli, insect cells, and yeast tend to have high failure rates regarding their ability to produce high titers of soluble, full-length, active target protein. In addition, the…

          The PfÄ“nex Expression Technologyâ„¢ platform is a powerful protein Expression Technology based on the novel host Pseudomonas fluorescens. Legacy recombinant protein expression hosts such as E. coli and yeast tend to have high failure rates with regard to expression of soluble, active protein. In addition, the time required to identify the optimal expression strain in these systems is protracted, resulting in significant opportunity cost for drug developers. Leveraging the PfÄ“nex Expression Technologyâ„¢ shortens development time…