On Wed, 10 Nov 2004 03:17:11 +0000 (UTC), William Morse
 wrote:

>r norman  wrote in
>news:cmm8va$27j3$1{at}darwin.ediacara.org: 
>
>> On Sat, 6 Nov 2004 18:33:02 +0000 (UTC), "Robert Karl Stonjek"
>>  wrote:
>> 
>>>Structured Water Is Changing Models
>>>Large water-molecule clusters may be crucial to cellular processes
>>>By Bennett Daviss
>>>
>>>Courtesy of Martin Chaplin
>>>
>>>Researchers are beginning to glimpse water's secret social life.
>>>Evidence is mounting that water in living systems naturally gathers
>>>into frameworks of 14, 17, 21, 196, 280, or more molecules. Some say
>>>that the clusters' apparent existence necessitates redesigning
>>>simulation models of life processes. And support is growing behind the
>>>idea that these intricate structures play key roles in operations
>>>ranging from molecular binding to turning on and off basic cell
>>>processes. 
>>>
>>>Such huge clusters certainly exist under some conditions, according to
>>>Richard Saykally, professor of chemistry at University of California,
>>>Berkeley. Saykally has spent years studying isolated water clusters
>>>using laser spectroscopy techniques that he developed. "There is no
>>>theoretical or practical limit on the size that these clusters could
>>>grow to," he says, adding that their life spans are limited only by
>>>their collisions with other molecules, an event that, within the
>>>stormy cell interior, usually occurs every few picoseconds.
>>>
>>>EVIDENCE AMASSING Using infrared spectroscopy, two research groups
>>>recently added to the evidence that clusters of dozens or even
>>>hundreds of water molecules exist in nature. Many chemists are
>>>intrigued by the uses nature might have for such structures. A team
>>>led by William Royer at the University of Massachusetts Medical
>>>School, Worcester, has shown experimentally that 17-molecule water
>>>clusters can serve as a communications medium between protein
>>>subunits. Chemist Martha Teeter at Boston College has found that
>>>clusters of 30 or more water molecules mediate some protein binding.
>>>Martin Chaplin at London's South Bank University posits an even more
>>>radical model for how cluster dynamics may make it possible for cells 
>>>to maintain ion gradients without spending energy. Further, he
>>>contends that collapsing water structures may serve as signaling
>>>switches in the cell. 
>>>
>>>Full Text at The Scientist.com
>>>http://www.the-scientist.com/yr2004/nov/research_041108.html
>>>
>>>Comment:
>>>Could this structure have also been a precursory form of life in, say,
>>>the ancient sea?
>>>
>>>Posted by
>>>Robert Karl Stonjek
>> 
>> Does anybody remember "polywater"?
>
>
>Yeah. While there may be something to this, my first thought is that 
>these "structures" are artifacts of cells containing high
concentrations 
>of molecules  that interact strongly with water. After all, if we were 
>looking simply at chemistry in dilute solutions, many of the reactions in 
>cells would not be energetically feasible. 
>

I was perhaps being a bit too cynical.  Structured water assemblies --
aka "shells of hydrations" around ions -- have long been known to be
important in determining relative ion permeabilities for ion channels.
And the whole notion of hydrophobic vs. hydrophilic interactions in
proteins in some sense also involves structuring within water.  17
molecule clusters are not that much of a stretch, although 30 molecule
clusters are starting to get a bit larger and are perhaps surprising
or a novel mechanism.

Water really is quite an amazing medium, a notion going all the way
back to Henderson (The Fitness of the Environment, 1913) and earlier.
That it still has a few surprises should be no surprise.
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