Do Prions Exist?

nygdan - here's a reference I recently found that I've been meaning to follow up on - it might be a totally unrelated red herring - but I suspect it relates to the fact that prions mutate into new strains in response to environmental change, as well as on exposure to different cells.



Occurrence of mutagens in canned foods.
Mutat Res. 1984 Nov-Dec;141(3-4):131-4. Krone CA, Iwaoka WT.
Mutagens are shown to be present in a variety of commercially heat-processed foods. Since these substances are not present in the unheated raw material, it appears that they are produced during processing. Canned salmon and beef broth showed the highest mutagenicity while other canned beef and fish products yielded lower but detectable levels. These findings are significant not only because of the large proportion of the food supply which is processed by canning, but also because the mutagens in these foods exhibit chemical behaviors and Salmonella strain specificity similar to mutagens in grilled foods which have been shown to be mammalian carcinogens.
PMID: 6392876

Originally posted by Nygdan

Originally posted by thermopolis
THE ENTIRE FOOD CHAIN is already infected. Fish, Veggies, MILK.

This should be trivially easy to demonstrate then, especially since the claim is that they pellet so easily. A centrifuge is not a particularly hard to get peice of equipment. Surely someone who beleives this can demonstrate it, or indeed, any professor with immuno-assay techniques can do this.

While I've not worked with prions per se... I have spun enough stuff in a centrifuge to know what's realistic and what's not. First off... yes, a centrifuge is easy to get. However, in order to spin down proteins, you need to be spinning really fast... really, really fast. That's the realm of ultracentrifuges, which aren't hard to come by either by are orders of magnitude more expensive than run of the mill units.

Let me put it to you this way... My Ph.D. work was on a HUGE protein, significantly bigger than a prion. There is no way it would have been practical for me to pellet that protein in an ultracentrifuge. Assuming you actually could pellet proteins in a realistic, workable protocol, if you don't have pure protein to start, you're pretty much going to get a big mess. So the argument is somewhat circular, you need pure protein to pellet in an ultracentrifuge, but you can isolate by pelleting...

The immunoassay thing is true more-or-less... the biggest thing is the availability of antibodies. I don't know if there are any commercial antibodies available for these things... probably are, but that's the critical thing. Also ELISA's are not the most sensitive assays in the world... I am not sure what kind of 'titer' is present in TSE affected samples, but realistically, if it's less than femtomolar concentrations... ELISA is probably going to generate more false positives than it's worth.

nygdan, mattison - where are you getting this "pelleting" business? My research says misfolded proteins aggregate, or clump together. Ie., if you used a process to create a smooth mixture, but got a lumpy mess instead, then most likely the proteins misfolded and aggregated.

Just semantics?

Originally posted by soficrow
nygdan, mattison - where are you getting this "pelleting" business? My research says misfolded proteins aggregate, or clump together. Ie., if you used a process to create a smooth mixture, but got a lumpy mess instead, then most likely the proteins misfolded and aggregated.

Just semantics?

Actually, I was kind of commenting on Nygdan's post... though I can't say for sure how 'pelleting' became an issue. I was merely offering my personal perspective on isolation and 'pelleting' of proteins.

Misfolded proteins often do aggregate... the aggregation of function of the overall hydrophobicity of the protein. Aggregation occurs as hydrophobic regions of a protein interact to escape aqueous or charged environments. Membrane proteins, which have a lot of hydrophobic residues tend to clump together more than cytoplasmic proteins. Though... misfolding doesn't necessarily imply aggregation.

As I understand it, prions clump together not as a function of misfolding per se, but as a function of both intermolecular and intramolecular electrostatic interactions between beta strand residues, ie: it's thermodynamically stable for them to clump together.

Originally posted by mattison0922

ie: it's thermodynamically stable for them to clump together.

Would you say that prions are more "stable" than normal proteins?

Originally posted by soficrow
Mutagens are shown to be present in a variety of commercially heat-processed foods.

I don't know if its relevant or not but it sure is disturbing!

[Assuming you actually could pellet proteins in a realistic, workable protocol, if you don't have pure protein to start, you're pretty much going to get a big mess.

I wouldn't think that it'd actually've worked, however the original poster did seem to be saying that it happens all the time, that you can just blend up a steak, centrifuge it, and you get an anomalous clumpy layer that is prions. Seemed surprising to me. I probably shouldn't've said pelleting either, I had just done a lab where we used bacteria with plasmids bearing a cancer gene, and in the end we 'pelleted' the bacteria out of suspension. Not entirely sure if the term should be used out of that context actually.

Originally posted by soficrow

Originally posted by mattison0922

ie: it's thermodynamically stable for them to clump together.

Would you say that prions are more "stable" than normal proteins?

Well, that HAS to be my assumption. Their stability is somewhat unprecedented... not to many proteins can take the kind of harsh treatment that prions can.

The native (correctly folded) form is most likely the version that has the lowest 'activation energy,' ie: the native state is easier to get to, but significantly less stable relative to the prion form. Apparently, in the absence of mutations, other misfolded proteins, or other as yet to be identified factors, the native conformation is the preferred energy minima. However, via some mechanism (IMO, probably nucleation), the native proteins can be induced to adopt this more difficult to attain, but significantly more stable conformation.

So bottom line: Native state easier to attain, more difficult to keep.
Misfoled 'prion' state more difficult to attain, but incredibly stable once it's assumed.

Originally posted by Nygdan
I probably shouldn't've said pelleting either, I had just done a lab where we used bacteria with plasmids bearing a cancer gene, and in the end we 'pelleted' the bacteria out of suspension. Not entirely sure if the term should be used out of that context actually.

The term 'Pelleting' is totally appropriate in this context. Supernatant and Pellet are pretty much universal centrifuge jargon.

You're not likely to hear too much about pelleting proteins though... mostly because of the impractical nature of the process.

[edit on 15-11-2005 by mattison0922]

Can I redirect your thread thermopolis? Please?

Here's my hypothesis - quick and dirty.

The premises: An infectious prion called "a-smooth muscle actin" (ASMA) is epidemic. Underlying ASMA infection is present in all modern disease, notably chronic disease, which is epidemic. ASMA can infect virtually any life form on the planet via actin proteins in cell membranes or cytoskeletons. At this point, ASMA and its various strains contaminate nearly everything natural and man-made.

The questions: How did ASMA become so widespread? What is the original source?

The Hypothesis:

Originally, ASMA mutated in part from a retrovirus called tobacco mosaic virus (TMV) contaminating the free cigarettes distributed to US troops in WWI. The mutation occurred in the presence of the first ever mass vaccinations, also given to WWI troops. The vaccines were contaminated with scrapie from sheep products used in the manufacturing process, resulting in a TMV/scrapie ASMA strain developing in smokers. The 1918 bird flu evolved very quickly from the original TMV/scrapie strain of ASMA, which hitchhiked on an already present influenza virus.

Also note: New strains of TMV related retroviruses also are epidemic in the plant world, and now infect a wide variety of different plants.

TMV is correlated with actin and myosin. Myosin is an actin-based molecular motor.

Correlation of tobacco mosaic virus with myosin and actin. Dokl Akad Nauk SSSR. 1953 Oct 1;92(4):851-3. RYZHKOV VL, LOIDINA GI. PMID: 13116901

Tobacco mosaic virus movement protein associates with the cytoskeleton in tobacco cells. Plant Cell. 1995 Dec;7(12):2101-14. McLean BG, Zupan J, Zambryski PC. Department of Plant Biology, University of California-Berkeley 94720-3102, USA. PMID: 8718621
www.plantcell.org...

Quick picks, also of interest:

How many phenotypes from one genotype? The case of Prion diseases.

"The usual assumption, namely that the underlying biochemical reactions in an organism tend to a unique steady-state, is shown to be not always correct. There are certain pathway mechanisms (e.g. positive feedback) which allow the system to exists in two alternative stable steady states. This bistability implies that environmental perturbations can switch the system from either state to the other. Such a switch takes place at the metabolic level and hence a single genotype can display two different, alternative, phenotypes without involving any changes in gene expression. The infective transmission of Scrapie-type diseases is explained here by such a mechanism involving protein-only changes."

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prion article list

Mutations in actin or actin-binding proteins have been found to cause several human diseases, ranging from hypertrophic cardiomyopathy to immunodefiencies such as Wiskott-Aldrich syndrome.

Effect of Self-Association on the Structural Organization of Partially Folded Proteins: Inactivated Actin

Regulation of gene expression by actinomycin D and other compounds which change the conformation of DNA.
Arch Biochem Biophys. 1969 Oct;134(1):34-41. Schwochau ME, Hadwiger LA. PMID: 5345595

Correlation of amino acid sequence and conformation in tobacco mosaic virus. Biophys J. 1968 Jan;8(1):29-39. Schiffer M, Edmundson AB. PMID: 5641402

Actin' Like Actin? Trends in Cell Biology 6:208-212. Mullins, R.D., Kelleher, J.F. and Pollard, T.D. (1996) [mullinslab.ucsf.edu...]More on actin from MullinsLab[/url]

I believe the first cross over occurred in Stanlyville with the duplication of the Polio vaccine. The "base" was chimp blood, tons and tons of chimp blood. Anyone who recieved that vaccine (over 1 million) could become a "breeding" ground for various mutated virus including "Ebola", Marburg and even HIV..........all from the same region near Stanleyville.

Prions have been around for aeons in "cooked" meats but in small quantities. It's almost like uranium in the earth, harmless until concentrated into a central mass.

When high speed centrifuge became "normal" equipment in biolabs prions became a byproduct of research that no one understood the implication.

"Critical mass" was reached because as you are aware prions can not be "killed" there is no nucleus, just amino acids in a misfolded chain that transfers its DNA in a yet unknow manner. It appears they reproduce much faster that anyone ever thought. Anywhere animal parts were fed to new 'stock" concentrated them throughout the food chain.

Soficrow, wasn't the 1918 flu strain considered a swine flu virus rather than a "bird flu" virus' and if so, couldn't the strain have mutated into a particularly lethal form to humans via people eating swine which had previoyusly eaten corpses on the battlefields in France? Cross over mutations would be expected in such a scenario, although of course this is all hypothetical at this point in time, as you note.

The 1918 bird flu evolved very quickly from the original TMV/scrapie strain of ASMA

Wait, what? The bird flu comes from that? Thats an interesting hypothesis, what do you see as being evidence that would refute it?

Originally posted by Nygdan

The 1918 bird flu evolved very quickly from the original TMV/scrapie strain of ASMA

Wait, what? The bird flu comes from that? Thats an interesting hypothesis, what do you see as being evidence that would refute it?

DNA evidence from the original strain would refute or support the hypothesis. Which is unavailable as it is defined as a "select agent." Apparently the controls may be loosened, but we have no assurance that the info will be either complete or accurate.

Also, DNA analysis of all major chronic diseases, to determine the presence of ASMA or track the evolution of new strains - also made unavailable around 2002, under the Bioterrorism Act.

Originally posted by thermopolis
I believe the first cross over occurred in Stanlyville with the duplication of the Polio vaccine. The "base" was chimp blood, tons and tons of chimp blood. Anyone who recieved that vaccine (over 1 million) could become a "breeding" ground for various mutated virus including "Ebola", Marburg and even HIV..........all from the same region near Stanleyville.

I agree that the SV40 contamination created a whole new raft of never-before-seen mutations. HIV-AIDS being only one example.

BUT - fibromuscular dysplasia (FMD) was acknowledged officially in 1938 in the USA - and FMD is the part of the disease process where ASMA uses the vascular and immune systems to spread through the body.

Plenty of other mutations occurred before the SV40/polio vaccine contamination. More important, the ASMA prion was spreading for a good 50 years before that event - and helps explain why and how so many new diseases arose from exposure to one single pathogen.

Prions have been around for aeons in "cooked" meats but in small quantities. It's almost like uranium in the earth, harmless until concentrated into a central mass.

When high speed centrifuge became "normal" equipment in biolabs prions became a byproduct of research that no one understood the implication.

"Critical mass" was reached because as you are aware prions can not be "killed" there is no nucleus, just amino acids in a misfolded chain that transfers its DNA in a yet unknow manner. It appears they reproduce much faster that anyone ever thought. Anywhere animal parts were fed to new 'stock" concentrated them throughout the food chain.

All true. Which highlights the complexity of complexity theory.

Seriously though, while bio-experimentation is a critical factor - it is not the only factor, nor the only critical factor. And don't forget, the presence of proteins and the use of centrifuges are common to many manufacturing processes.

There is no doubt that ASMA started spreading in the early 1900's. IMO - the TMV/scrapie hypothesis may explain ASMA's origins.


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Originally posted by michaelanteski
Soficrow, wasn't the 1918 flu strain considered a swine flu virus rather than a "bird flu" virus'

QUOTE:

"Scientists have reconstructed the genetic code of the deadly 1918 "Spanish flu," which swept the globe and killed an estimated 20 to 40 million people. Among their findings: The 1918 virus strain developed in birds and was similar to the "bird flu" that today has spurred fears of another worldwide epidemic."




Sorry - forgot to credit quote.



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[edit on 16-11-2005 by soficrow]

Also, from the BBC:


QUOTE:


1918 killer flu 'came from birds'

"The Spanish flu virus that killed up to 50 million people in 1918-19 was probably a strain that originated in birds, research has shown.

US scientists have found the 1918 virus shares genetic mutations with the bird flu virus now circulating in Asia."



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Originally posted by michaelanteski
Soficrow, wasn't the 1918 flu strain considered a swine flu virus rather than a "bird flu" virus' and if so, couldn't the strain have mutated into a particularly lethal form to humans via people eating swine which had previoyusly eaten corpses on the battlefields in France? Cross over mutations would be expected in such a scenario, although of course this is all hypothetical at this point in time, as you note.

Try this............original source of H1N1.......swine flu

Here is something I never saw coming. Venus is the source of 55 viral outbreaks?

www.ebicom.net...

Originally posted by thermopolis
Here is something I never saw coming. Venus is the source of 55 viral outbreaks?

www.ebicom.net...

I did. Am working on a script where aliens deny liability and culpability for prions.

The "alien protein" gambit is Plan C - totally predictable. Plan A is "Prions don't exist." Plan B is blame prions on the terrorists.

So what's the truth? My hypothesis #2: ASMA is the grandaddy prion - now an out of control corporate destabilization bioweapon, released via cigarettes and vaccines in 1915.


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Originally posted by soficrow

Originally posted by thermopolis
Here is something I never saw coming. Venus is the source of 55 viral outbreaks?

www.ebicom.net...

I did. Am working on a script where aliens deny liability and culpability for prions.

The "alien protein" gambit is Plan C - totally predictable. Plan A is "Prions don't exist." Plan B is blame prions on the terrorists.

So what's the truth? My hypothesis #2: ASMA is the grandaddy prion - now an out of control corporate destabilization bioweapon, released via cigarettes and vaccines in 1915.


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OK here is the truth about prions..........

Prions is to western civilization as LEAD pipes was to Rome. It is a product of a failed technology that some suspect but the "Gov" knows it is too dispersed throughout the "empire" to stop.

My "personal" research indicates that specific mal-formed amino acids dating back to the start of the use of electromagnetic energy is the original source of prions. Electromagnetic fields have directly and originally caused mutations is natural DNA chains that became the "soup" of virus "enhancments". The man in his wisdom began to "tweek" this soup into bioweapons. H1N1 was the first manipulated bioweapon. Marburg Germany biolab began in the late 1800's. The first spanish flu outbreak was in Ft Riley Kansas with "soldiers" returning from germany.

???????? Interesting isn't it............

Now we have "marburg" version of Ebola............