A BRIEF REVIEW ON DEVELOPMENT OF HIGH YIELD PROCESS IN ESCHERICHIA COLI FOR PRODUCTION OF RECOMBINANT CARRIER PROTEIN (CRM197)

It is a well-established fact that bacterial polysaccharide – protein conjugate vaccine have made a huge impact on pediatric vaccination approach. The immunogenicity of polysaccharide is enhanced by coupling them to carrier proteins. The widely used carrier proteins are tetanus toxoid (TT), diphtheria toxoid (DT) and diphtheria toxoid variant CRM197. DT conjugates are less immunogenic, TT conjugates renders reduced polysaccharide response whereas CRM197 are at lower risk for this. Cross Reacting Material (CRM197), a non-toxic variant of diphtheria toxin. Conventionally, CRM197 is isolated by fermentation of Corynebacterium diphtheriae C7 (β197) cultures, which often suffers from low yield. Several recombinant approaches have been reported with robust processes and higher yields, which will improve the affordability of CRM197-based vaccines. Escherichia coli based recombinant CRM197 carrier protein can be a revolutionary approach to get low cost and high yield carrier protein to serve the need of time and fulfill the demand of ever rising population of the world.