Prospects for the Production of Recombinant Therapeutic Proteins and Peptides in Plants: Special Focus on Angiotensin I-Converting Enzyme Inhibitory (ACEI) Peptides

Molecular pharming is a cost-effective, scalable, and safe system to produce high-quality and biologically active recombinant therapeutic proteins. Thus, plants are emerging alternative platform for the production of pharmaceutically relevant proteins such as vaccines, antibodies, antibody derivatives, and some serum-derived proteins. Additionally, plants have also been used to produce bioactive and immunogenic peptides. The efficacy, selectivity, specificity, and low toxicity make them particularly well-suited therapeutic agents for various indications, for instance, cardiovascular and infectious diseases, immunological disorders, and cancer. In the broad range of known bioactive peptides, angiotensin I-converting enzyme inhibitory (ACEI) peptides derived from food proteins have attracted particular attention for their ability to prevent hypertension. So far, several ACEI peptides have been identified in food proteins, mainly in milk, eggs, and plants. The industrial production of ACEI peptides is based on enzymatic proteolysis of whole food proteins, which leads to the release of small bioactive peptides with ACE-inhibitory activity. The problems associated to such procedures, namely, cost and loss of functional properties, have demonstrated the need to develop more straightforward methods to produce ACEI peptides. One viable hypothesis, discussed in this chapter, is to genetically engineer crop plants to produce and deliver antihypertensive peptides.