Subject: E.coli

From: Roberto Verzola <[email-masked]>
Date: Mon, 4 Nov 2002 11:02:07 +0800

My thanks to Joe Cummins and Frank Teuton for the E.coli
explanation.

So far, this is what I've learned:

- most of hundreds of E.coli strains are harmless (in fact, we need
the E.coli inside our gut because they produce some vitamins for
us)

- a few strains are harmful, and the one which has received the
most coverage recently is the O157:H7 strain, which causes a form
of diarrhea which can be fatal.

- the presence of E.coli in water is used as *indicator*. While the
E.coli itself may not be harmful, its presence implies possible fecal
contamination of the water. Such fecal contamination means other
contaminants -- this time pathogenic -- may also be present.

- E.coli is both aerobic and anaerobic (ie, it can survive in either
environment); this seems to contradict recent exchanges on Sanet
re compost teas which implied that aeration kills E.coli. Apparently
not. Can Elaine Ingram clarify this?

- E.coli has been the most common target of bacterial genetic
engineering. ie, all kinds of genes and plasmids have been inserted
into E.coli. Another question for Joe Cummins: is it possible that
these genetic manipulations created the pathogenic strains of
E.coli?

Regards to all,

Roberto Verzola
Philippines

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From: jcummins <[email-masked]>
Date: Sun, 3 Nov 2002 23:40:07 -0500

Hi Roberto,
In reply to your question as to whether or not E coli 0157:H7 and the
other verotoxin toxin strains acquired the toxin gene by laboratory
genetic engineering. There has been serious discussion in the literature
debating that point. There is evidence that the verotoxin genes can be
transmitted born on a transducing bacteriaphage (meaning that the toxin
genes may be transmitted between bacteria on a virus). It seems most
likely that the transfer of the toxin genes is a natural phenomenon and
one amplified by growing problem of the proximity of farm animals and
people, feedlot fattening of range cattle in the corn county has created
a lot of poop near fruit and vegetable farms and near main municipal wells.
The people made ill have bloody diarrhea but most of those killed or
crippled suffer kidney and later other organ damage from the verotoxin.
It has been claimed that the pasture or feedlot  run off of the bacteria
can be greatly reduced by adding the plastic , polyacrylamide, to the
pasture soil.
Hope this discussion helps, Cheers, Joe

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