Why are most recombinant human proteins produced in animal or plant hosts instead of bacterial host cells?

Key Concepts

Post-Translational Modifications

Recombinant proteins often require specific post-translational modifications, such as glycosylation, phosphorylation, and proper folding, to function correctly. Animal and plant cells have the necessary cellular machinery to perform these modifications, which are often absent or insufficient in bacterial systems, leading to improperly folded or inactive proteins.

Protein Folding and Assembly

The correct folding and assembly of proteins are crucial for their biological activity. Eukaryotic cells, such as those from animals and plants, provide a more complex environment that supports proper protein folding and assembly, while bacterial cells may lead to the formation of inclusion bodies, where proteins aggregate and lose functionality.

Protein Yield and Secretion

Eukaryotic systems, including animal and plant hosts, often allow for higher yields of functional recombinant proteins and can secrete them into the culture medium. This is advantageous for purification processes, as it simplifies the recovery of the desired protein, unlike bacterial systems where proteins may remain intracellular or require additional steps for extraction.