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.
-- Davin
