[sci.bio] Help with Handedness and Taste of Sugars

bolle@janus1.de (Andre' Bolle) (07/06/90)

This is a very simple question. It requires a yes or answer. If I get
no response I will assume that no-one yet knows.

Can a D-sugar and an L-sugar (or any other edible L-/D- pair) taste the same?

andre'

crown@physics (Rick Crownover) (07/10/90)

My understanding is that D- and L-sugars have identical flavor
--> the frequent suggestion of sweeteners with zero calories;
however, the glitch... the optical isomer sugars are not
produced abundantly by nature's plant factory, and are very
expensive to synthesize from scratch.

--
	Richard L. Crownover, Ph.D., MS II	(919) 682-7386
        Duke University Dept. of Physics	crown@physics.phy.duke.edu
	Duke University School of Medicine	DUMC Box 2736
	Durham, N.C.      27706

teexmmo@ioe.lon.ac.uk (Matthew Moore) (07/10/90)

In article <655@ecrc.UUCP> bolle@janus1.de (Andre' Bolle) writes:
>
>This is a very simple question. It requires a yes or answer. If I get
>no response I will assume that no-one yet knows.
>
>Can a D-sugar and an L-sugar (or any other edible L-/D- pair) taste the same?
>
>andre'


Can I ask a question instead? (well I will anyaway)

Is taste a function which uses chemical (and physical) properties, or
does it use the molecular shape?

My impression is that, unlike smell, taste probably uses chemical
properties, as it gives information on properties such as sweetness,
bitterness, sourness, and salinity.

Smell on the other hand, which gives much more detailed information,
probably uses molecular shape receptors.

So my answer to the question is that an L/D pair may taste the same,
but would smell different. (If you could smell them). 

Confused?

werner@aecom.yu.edu (Craig Werner) (07/15/90)

In article <1990Jul10.162638.18896@ioe.lon.ac.uk>, teexmmo@ioe.lon.ac.uk (Matthew Moore) writes:
> 
> Can I ask a question instead? (well I will anyaway)
> 
> Is taste a function which uses chemical (and physical) properties, or
> does it use the molecular shape?
> 
	There are two extremely sweet naturally occuring proteins for
which the complete crystal structure is known.  There appears to be
absolutely nothing in common between their structures.  Glucose looks
absolutely nothing like Nutrasweet, yet the latter is very very sweet,
but most other dipeptides are not.
	Nobody really knowns what chemical property defines 'sweet.'
-- 
	        Craig Werner   (future MD/PhD, 5.5 years down, 2.5 to go)
	     werner@aecom.YU.EDU -- Albert Einstein College of Medicine
              (1935-14E Eastchester Rd., Bronx NY 10461, 212-931-2517)
                   "Viruses do to cells what Groucho did to Freedonia."