High-level expression of angiotensin converting enzyme inhibitory peptide Tuna AI as tandem multimer in Escherichia coli BL21 (DE3)

- We establish a system for expressing Tuna AI as tandem multimer in Escherichia coli.
- The fusion protein Fusion-32TunaAI shows the highest expression level.
- The obtained Tuna AI is confirmed and shows high activity in vitro and in vivo.
- We establish two economic protocols for protein and peptide purification.