Species differences in T1R2 receptor residues cause varied sweet taste responses to artificial sweeteners like aspartame and neotame.

The sweet taste receptor’s sensitivity to artificial sweeteners differs among species due to variations in key amino acid residues in the T1R2 subunit. Humans, apes, and Old World monkeys perceive aspartame as sweet, while rodents and New World monkeys do not. Studies pinpoint residues such as S40 and D142 in human T1R2 as critical for binding these sweeteners, highlighting how subtle molecular differences shape taste perception across species.