Recombinant DNA technology allows scientists to isolate genes from one organism and introduce them into another organism to produce proteins of interest. This technology has revolutionized biotechnology and is used to produce many therapeutic proteins and vaccines.
Gene Cloning
The first step in producing a recombinant protein is to isolate the gene encoding the protein of interest. This gene is then inserted into a plasmid vector that can replicate inside a host cell like bacteria or yeast. This process of isolating and inserting a gene into a vector is called aggregation gene cloning. The plasmid vector contains elements that allow it to replicate inside the host and also contains a promoter that drives expression of the inserted gene. It takes place within a heterologous system.
Protein Expression
The recombinant plasmid is then introduced into host cells like E. coli or yeast where it replicates and expresses the protein of interest. The host cells essentially become protein production factories. However, high levels of protein expression can sometimes lead to the formation of insoluble aggregates of misfolded proteins called inclusion bodies. Strategies like lowering growth temperature can improve these issues with insoluble proteins.
Protein Purification
The expressed proteins must then be purified away from all the other cellular proteins. This involves techniques like centrifugation, chromatography, and electrophoresis. The purity and yield of the purified protein are analysed using assays. The purified proteins may require additional modifications like cleavage of affinity tags.
Product Formulation
The purified recombinant proteins are then formulated into a stable preparation by adding stabilizing agents. The formulated bulk protein is filled into vials for storage and distribution. Proteins are extremely sensitive to temperature changes so the vial filling must be kept in cold storage to maintain stability.
Applications
Recombinant DNA technology has enabled the production of many therapeutic proteins like insulin, growth hormones, and monoclonal antibodies. It has also allowed innovative vaccines to be developed more rapidly compared to traditional methods. Overall, this technology has revolutionized medicine and biotechnology.