Tuesday, March 15, 2005

Leaving a Bitter Taste
I'm supposed to be resting after surgery. But a visit to the doctor to make sure that all is going as planned and that nothing is in danger of falling off (even though the color due to bruising is highly suggestive of exactly that scenerio) has me dropping into the lab to see what's on the slab. Among the pile is the March 10th issue of the science journal Nature with a letter entitled "The receptors and coding logic for bitter taste" by KEN L. MUELLER, MARK A. HOON, ISOLDE ERLENBACH, JAYARAM CHANDRASHEKAR, CHARLES S. ZUKER & NICHOLAS J. P. RYBA. Nature 434, 225–229, (2005)

The synopsis provided is as follows: Almost every naturally occurring toxin tastes bitter, so the ability to detect bitterness is vital to animals as a means of avoiding poisonous substances. The T2R family of receptors, found on the tongue and palate epithelium, are implicated in bitter taste sensing. A combination of genetic, behavioural and physiological studies now confirms that T2R receptors are necessary and sufficient for the detection and perception of bitter compounds. Intriguingly the system can be subverted: bitter can be the new sweet. Mice engineered to express a bitter taste receptor in what are normally 'sweet' cells display strong attraction to this family of bitter compounds. So the 'taste' of a sweet or a bitter compound is a reflection of how the specific receptors are wired, rather than a property of the receptors or even of the tasted molecules themselves.

So it is true that an aversion to bitter is a good thing, but if you actually do like bitterness then maybe, just maybe, your sweet/bitter receptors have been mixed up!

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