X-Message-Number: 19675
From: 
Date: Thu, 1 Aug 2002 23:01:36 EDT
Subject: Some Comments on Extremophiles

H. Tindale,

This Tuesday, you suggested extremophiles as an interesting area for 
research.  Maybe so.  I have an interest in those that thrive under huge 
hydrostatic pressure -- like several miles deep in the sea. I saw a 
documentary on TV not too long back where some scientist had captured some 
basically unknown species of small squid with one of these one or two-man, 
pressurized, motorized deep sea vessels.  Back on the research boat/ship, 
their squids only lived a few hours in the aquariums they had prepared.  The 
scientists were portrayed as being perplexed as to why they did not survive.  
My guess would be the lack of pressure they were use to and required (I'm 
sure they considered the same thing, though). I am wondering if proteins -- 
dependent on the pressure for their proper conformations -- were denatured.  
But more obvious might be the pressure-based disruption of their handling and 
usage of gaseous compounds (e.g., CO2) and elements (e.g., O2) in the squids' 
bodies. (Too much oxygen availability may have even been a problem.)

Does this have anything to do with anything particularly relevant? Possibly. 
I may post some ideas later on, but here's a quick thought: Quick pressure 
release on a substance (or organism) reduces its temperature instantly and 
consistently throughout its mass -- perhaps assisting in the bridging of a 
critical temperature threshold, or two, for the totality of an organism's 
cells during cryopreservation or temperature-based suspended animation.  If 
this process (i.e., either or both of the pressurizing & depressurizing) is 
not too damaging to the specimen, the idea may have some experimental value.

Here is some text I found of interest on how humans can react to *very 
subtle* changes in atmospheric pressure (as opposed to orders of magnitude, I 
believe, for the squids cited):

"You take a balloon and you put it into
a vacuum. As the pressure is reduced
around that balloon, it expands," he
explained. "And so the same thing
within the tissues around the joints.
If there's already swelling, inflam-
mation, abnormal mechanics in the
joint, as the pressure goes down, the
gas and tissue expand, and this is felt
as more pain by the patient. This is
why they sense a change in baro-
metric pressure."

Here is a brief accounting of extremophiles:

http://www.wikipedia.com/wiki/Extremophile

Regards,

D.C. Johnson

PS. The recently "CryoNet-cited" article by Rand Simberg was excellent in my 
opinion. (Sorry, I downloaded the article but neglected to get the URL.)  I 
noticed that he has posted in the past on CryoNet.

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