Bitter tastant

Abietane diterpenes (C61C61C6 with varying degrees of unsaturation) include the 5-LOX inhibitor abietane, the GABA(A) receptor antagonist taxodione and the bitter tastant carnosol. 

Clerodanes involve a (C61C6) group variously linked to furan (unsaturated C40), pyran (unsaturated C50), methyleneoxy and methylenedioxy rings. Clerodanes include bitter tastants and antifeedants as exemplified by the extremely bitter component columbin of the bitter tonic made from roots of Jateorhiza columba (columba root) (Menispermaceae). 

Cucurbitacins are oxygenated triterpenes (C30 typical skeletal structure G6 G6 G6 ] C5-Cg) that can be glycosylated. Cucurbitacins are typically bitter tastants and... 

There are some hundred different 7TM receptors involved in perception of bitter tastants. The bitter taste receptors also couple through the G protein gustducin yielding the activated Gag-GTP which can thence activate C.AMP/C.GMP phosphodiesterase, thus lowering cAMP and cGMP concentration. Bitter tastant receptors can also act via pertussis... 

Floriano WB, Hall S, Vaidehi N, Kim U, Drayna D, Goddard WA 3rd. Modeling the human PTC bitter-taste receptor interactions with bitter tastants. J. Mol. Model. 2006 12 931-941. 

A central question in bitter taste research is if bitter taste receptor cells are broadly tuned sensors for most, if not all, bitter tastants, or if bitter taste receptor cells are rather heterogeneous, thus providing a potential cellular basis for a discrimination... 

Oquendo P, Hundt E, Lawler J, Seed B (1989) CD36 directly mediates cytoadherence of Plasmodium falciparum parasitized erythrocytes. Cell 58 95-101 Pittman DW, Labban CE, Anderson AA, O Connor HE (2006) Linoleic and oleic acids alter the licking responses to sweet, salt, sour, and bitter tastants in rats. Chem Senses 31 835-843 Pittman D, Crawley ME, Corbin CH, Smith KR (2007) Chorda tympani nerve transection impairs the gustatory detection of free fatty acids in male and female rats. Brain Res 1151 74-83... 

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