The T1R3 subunit of the sweet taste receptor is activated by D2O in transmembrane domain-dependent manner.

Deuterium oxide (D2O) is water in which the heavier and rare isotope deuterium replaces both hydrogens. We have previously shown that D2O has a distinctly sweet taste, mediated by the T1R2/T1R3 sweet taste receptor. Here, we explore the effect of heavy water on T1R2 and T1R3 subunits.

Sensitivity of human sweet taste receptor subunits T1R2 and T1R3 to activation by glucose enantiomers.

We have previously shown that l-glucose, the non-caloric enantiomer of d-glucose, activates the human sweet taste receptor T1R2/T1R3 transiently expressed in HEK293T cells. Here, we show that d- and l-glucose can also activate T1R2 and T1R3 expressed without the counterpart monomer. Serine mutation to alanine in residue 147 in the binding site of T1R3 VFT domain, completely abolishes T1R3S147A activation by either l- or d-glucose, while T1R2/T1R3S147A responds in the same way as T1R2 expressed without its counterpart.

Taste GPCRs and their ligands.

Taste GPCRs are expressed in taste buds on the tongue and play a key role in food choice and consumption. They are also expressed extra-orally, with various physiological roles that are currently under study. Unraveling the roles of these receptors relies on the knowledge of their ligands.

Taste and chirality: l-glucose sweetness is mediated by TAS1R2/TAS2R3 receptor.

Naturally occurring sugars usually have d-chirality. While a change in chirality typically affects ligand-receptor interaction, non-caloric l-glucose was reported as sweet for humans. Here we show that l- and d-glucose have similar sensory detection thresholds (0.

Comprehensive structure-activity-relationship studies of sensory active compounds in licorice (Glycyrrhiza glabra).

Licorice saponins, the main constituents of Glycyrrhiza glabra L. roots, are highly appreciated by the consumer for their pleasant sweet and long lasting licorice taste. The objective of the present study was to understand the molecular features that contribute to bitter, sweet and licorice sensation of licorice roots, and whether individual compounds elicit more than one of these sensations.

Sweet taste of heavy water.

Hydrogen to deuterium isotopic substitution has only a minor effect on physical and chemical properties of water and, as such, is not supposed to influence its neutral taste. Here we conclusively demonstrate that humans are, nevertheless, able to distinguish DO from HO by taste. Indeed, highly purified heavy water has a distinctly sweeter taste than same-purity normal water and can add to perceived sweetness of sweeteners.

Structure-based screening for discovery of sweet compounds.

Sweet taste is a cue for calorie-rich food and is innately attractive to animals, including humans. In the context of modern diets, attraction to sweetness presents a significant challenge to human health. Most known sugars and sweeteners bind to the Venus Fly Trap domain of T1R2 subunit of the sweet taste heterodimer.

Bitter and sweet tasting molecules: It's complicated.

"Bitter" and "sweet" are frequently framed in opposition, both functionally and metaphorically, in regard to affective responses, emotion, and nutrition. This oppositional relationship is complicated by the fact that some molecules are simultaneously bitter and sweet. In some cases, a small chemical modification, or a chirality switch, flips the taste from sweet to bitter.

Biomimetic Sensors for the Senses: Towards Better Understanding of Taste and Odor Sensation.

Taste and smell are very important chemical senses that provide indispensable information on food quality, potential mates and potential danger. In recent decades, much progress has been achieved regarding the underlying molecular and cellular mechanisms of taste and odor senses. Recently, biosensors have been developed for detecting odorants and tastants as well as for studying ligand-receptor interactions.