{Reference Type}: Journal Article {Title}: Study on the Thermal Stability of the Sweet-Tasting Protein Brazzein Based on Its Structure-Sweetness Relationship. {Author}: Zuo J;Zheng W;Shi N;Song R;Han F;Yang C;Li J;Peng C;Li B;Chen Y; {Journal}: J Agric Food Chem {Volume}: 72 {Issue}: 13 {Year}: 2024 Apr 3 {Factor}: 5.895 {DOI}: 10.1021/acs.jafc.3c09616 {Abstract}: Brazzein (Brz) is a sweet-tasting protein composed of 54 amino acids and is considered as a potential sugar substitute. The current methods for obtaining brazzein are complicated, and limited information is available regarding its thermal stability. In this study, we successfully expressed recombinant brazzein, achieving a sweetness threshold of 15.2 μg/mL. Subsequently, we conducted heat treatments at temperatures of 80, 90, 95, and 100 °C for a duration of 2 h to investigate the structural changes in the protein. Furthermore, we employed hydrogen-deuterium exchange coupled to mass spectrometry (HDX-MS) to analyze the effect of heating on the protein structure-sweetness relationships. Our results indicated that the thermal inactivation process primarily affects residues 6-14 and 36-45 of brazzein, especially key residues Tyr8, Tyr11, Ser14, Glu36, and Arg43, which are closely associated with its sweetness. These findings have significant implications for improving the thermal stability of brazzein.