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Hello Twim team,
After reading the Pasteur lecture.
It seems that the idea of using the Pseudomonas aer, "coal & septicemia" came from a demonstration that the "bactericidie" in the blood from animal with anthrax ("sang charbonneux") was the only origin of the disease.
It was a point of contention in the fight against the last supporters of the spontaneous generation.
When use the "sang charbonneux" from death animals collected at a rendering facility was shown to kill rabbit, but without the presence of the bactericidie in the rabbit blood.
Pasteur was able to demonstrate that was due to contamination of the corps blood between the time of death & the collection, by the "virions" causing "septicemie". And that's was causing the destruction of the "coal virulence" (virulence charbonneuse). For him it was of therapeutic interest, but it seems he has never used it on human (only on guineapigs).
He has developed instead the vaccination against anthrax by selection of an attenuated variant.
By the way fun coincidence with Michael remarque to Elio about the LON & E coli turning to snakes.
In the same lecture Pasteur also observed that outside of the blood in septicemia killed guinea pigs, the bactericidies form long snake like filament "creeping, sinuous, and separating the blood cells as a snake separate the grass in the bushes".
I have never been as excited about a podcast as I was when I saw the title of the latest episode of TWIM (#51, Cave science with Hazel Barton), and it definitely did not disappoint! I listened to it twice right away. I'm trying to specialize in metagenomics, and I love caves and caving. If someone had asked me to design my dream TWIM, it would have been exactly like this. I had actually thought about suggesting the antibiotic resistance in cave microbes -paper for discussion, but I didn't think anyone else would find it interesting - probably because I come from a country with no proper caves, where you only get blank stares when you mention caving. Thank you so much for this episode!
I also have a question. Dr. Barton mentioned they have tried to do 454 sequencing, but apparently they haven't published anything about that yet? Do any of you know of any sequencing-based cave microbiome papers, particularly about "normal" karst caves? I've been unable to find anything on my own.
Thank you once more for the most awesome podcast episode ever,
(your subway-driving fan from Finland)
[I asked Hazel. She wrote:]
Yeah, unfortunately we've done a ton, but the papers aren't done.
Here's some good references though:
Making a living while starving in the dark: metagenomic insights into the energy dynamics of a carbonate cave. Ortiz et al, ISME J, 2013 (1-14).
Life in the dark: metagenomic evidence that a microbial slime community is driven by inorganic nitrogen metabolism. Tetu et al, ISME J, 2013(7), 1227-1236
One of the other podcasts I listen to is CBC Radios' Quirks and Quarks. I find it always interesting, and often profound.
The segment I was just blown away by was this one: http://www.cbc.ca/quirks/2014/03/15/2014-03-15-1/.
It put together many of the keywords I have heard from your podcasts, and added a new one- "host-defence peptides".
It even made me consider what are "biofilms", a term I have heard you use but never thought significant.
So. as something different, would you consider reviewing this radio segment as you do a paper? You could bring into the discussion regular papers that are relevant, too.
And, a final question, what ARE biofilms and what are their significance?
Thanks for doing what you do (even though I understand 25% of it).
Dear Dr. Racaniello,
In your latest TWIM (#72?), I heard you wonder out loud why a virus such as polio managed just fine without virulence whereas one such as norovirus seemed to relish it.
Might the answer have something to do with the work of Dr. Graham Rook at University College, London? His Old Friends hypothesis (a re-formulated hygiene hypothesis) distinguishes between microbes that inhabited hunter-gatherer hominids before we lived in cities (like hepatitis A and H/ pylori, which protect against allergies/asthma/autoimmune diseases) and those more recently evolved to infect humans living in sufficient population densities to support epidemics (like measles, which does NOT protect against a/a/a).
Maybe virulence evolved as an adaptation to crowds?
Just a thought,
P.S. My mother's family has the name Ianiello, which means--maybe 500 years ago or so--our families may have known each other. Just another thought.