How animals in the hydrothermal vent can live with the high temperature.

Jonathan Silverlight jsilver at merseia.fsnet.co.uk
Fri Mar 29 17:22:10 EST 2002


In message <3ca62a11.27924152 at news.earthlink.net>, Davin C. Enigl 
<enigl at aol.com> writes
>On Fri, 29 Mar 2002 15:10:21 -0600, "Paul F. Dietz"
><dietz at interaccess.com> wrote:
>
>>"Davin C. Enigl" wrote:
>>
>>> Yet, I read prions survive 1000C for 1 hour, and higher temperatures
>>> that would normaly "ash" naked amino acids.
>>
>>I seriously doubt prions survive unchanged for 1 hour at 1000 C.
>>Perhaps they get converted to a carbonized nanolump that
>>has a similar shape and can initiate the same conformational
>>chain reaction in the affected proteins.
>>
>>      Paul
>
>Well, never-the-less the I read article claimed the prion was still
>caused BSE, so I was not affected very much if at all -- certainly not
>to the point where anyone would claim they were denatured.
>
>This "survival after ashing" was also stated as a fact, by Paul
>Brown's research at the US National Institutes of Health.
>
>As you know, catalysts like prions must be quite specific via the
>"lock and key" theory.   Therefore, I can not see how a break in say,
>the beta sheet conformation could still cause disease.  The alpha
>helical form (normal) is easily denatured however.
>
>Also, sterilization by heat alone is not enough to make me comfortable
>. . .  we add a 1.0 M NaOH flood over the item to be sterilized and
>then autoclaving at 132  C for 5 hours is our current standard, --
>UCSF recommended this some years ago.  I am not sure what F sub-zero
>at 132C that works out to for 1000C for 1 hour dry heat, -- but the
>NaOH water solution certainly must lower the D-value more than
>autoclaving alone.
>
>This has significance for extreme-ophile research and
>Astromicrobiology theory.

If you're thinking of the paper I think you are (it's on-line at the 
PNAS web site) they _didn't_ find infectivity at 1000C but they did at 
600C. Their theory is that some inorganic matrix survives at that 
temperature but not at 1000C.
BTW, isn't 2.0 M NaOH now recommended?




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