Poster Presentation International Peptide Symposium 2023

Salty peptide derived from the sweetness loops of sweet-tasting protein (#277)

Si-Wook Jang 1 , Hyun-A Kim 1 , Na-Hee Jung 1 , Seo-Young Park 1 , Kwang-Hoon Kong 1
  1. Chung-Ang University, Seoul, South Korea

Humans perceive five tastes through taste buds: sweet, bitter, sour, salty, and umami. Identifying sweet foods is especially important as they provide a means of finding necessary carbohydrates that are highly nutritious. However, excessive consumption of carbohydrate sweeteners causes diabetes and obesity. For this reason, there is a high demand for non-caloric protein-based sweeteners with excellent taste characteristics. We have identified critical residues important for sweetness of the sweet-tasting protein brazzein and its antioxidant, anti-inflammatory, and anti-allergic activities. In this study, four peptides derived from the β-strand III and the β-turn structures of brazzein were designed, synthesized, and characterized. The tastes of the synthesized peptides were assayed by sensory analysis. None of the designed peptides demonstrated a sweet taste and two peptides showed a salty taste. The results of docking tasks indicated that the binding sites that bind the designed peptides to the sweet taste receptor are different from the one that binds aspartame. Synthetic genes for salty taste peptides were introduced into Kluyveromyces lactis, a yeast strain certified as a GRAS (generally recognized as safe) strain. Expression and purification conditions were optimized to maximize expression of salty peptides. This K. lactis expression system is useful for mass-producing recombinant taste-related peptides in high purity and yield at low production cost and has promising applications in the food industry.