A Super Stable Mutant of the Plant Protein Monellin Endowed with Enhanced Sweetness

Life

Piero Porcaro¹  Gaetano Cardinale¹  Delia Picone²  Luigi Petraccone²  ErosAntonio Lampitella²  Serena Leone²  Masoud Delfi²  Alessandro Emendato² 

[1] Consorzio Sannio Tech, Strada Statale Appia Km 256 n.7, 82010 Apollosa, Benevento, Italy;Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelo, Via Cintia, 80126 Napoli, Italy;

关键词: sweet proteins;    single-chain monellin (MNEI);    sensory analysis;    shelf life;    high intensity sweeteners;    thermochemical stability;   

DOI  :  10.3390/life11030236

来源: DOAJ

【 摘 要 】

Sweet proteins are a class of proteins with the ability to elicit a sweet sensation in humans upon interaction with sweet taste receptor T1R2/T1R3. Single-chain Monellin, MNEI, is among the sweetest proteins known and it could replace sugar in many food and beverage recipes. Nonetheless, its use is limited by low stability and high aggregation propensity at neutral pH. To solve this inconvenience, we designed a new construct of MNEI, dubbed Mut9, which led to gains in both sweetness and stability. Mut9 showed an extraordinary stability in acidic and neutral environments, where we observed a melting temperature over 20 °C higher than that of MNEI. In addition, Mut9 resulted twice as sweet than MNEI. Both proteins were extensively characterized by biophysical and sensory analyses. Notably, Mut9 preserved its structure and function even after 10 min boiling, with the greatest differences being observed at pH 6.8, where it remained folded and sweet, whereas MNEI lost its structure and function. Finally, we performed a 6-month shelf-life assessment, and the data confirmed the greater stability of the new construct in a wide range of conditions. These data prove that Mut9 has an even greater potential for food and beverage applications than MNEI.

【 授权许可】

Unknown