Viruses: alive or not?

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posted on Aug, 31 2012 @ 11:42 AM
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So I’m gonna discuss something I find particularly fascinating. Probably because I’m gross and like growing things on petri-dishes. So microbiology has become a massive interest for me within the university course I’m studying. But I found out something particularly interesting that could, potentially, make us rethink everything we’ve thought about viruses so far. And I like when things aren’t straight forward. So let’s get on it.

The Case

In 1992, there was a particularly nasty outbreak of pneumonia in Bradford, England. Looking for the cause, they found an amoeba growing in a water tower. This amoeba was Acanthamoeba polyphaga and was believed to be a gram-positive bacterium after initial gram staining techniques. They named it (pretty unimaginatively) Bradfordcoccus and shoved it in a fridge.

In 2003, the sample was sent to the Université de la Méditerranée in Marsielle which is one of the greatest microbiology research centres in the world and they did some tests. Mainly, they put some RNA to join to the bacterium.

And they found that it wasn’t a bacterium.

It was, in fact, a virus. The biggest virus any one had ever come across. The fella who found it named it ‘Mimi’, short for mimicking virus – for its bacteria-impersonating properties - (and in homage to the name of a bacterium that his father told him a story about when he was a kid).

The Virus

Now, Mimi is fairly complex. Okay, very complex. The biggest virus we’d ever found until 2010 when Mamavirus took that crown, and still the most complex.

See, we think of viruses as something simple. The infection mechanism is impressive, but viruses aren’t what we class as ‘alive’. (Classification of life is something along the lines of MRS GREN as popularly taught in early education; movement, respiration, sensitivity, growth, reproduction, excretion and nutrition)).They have to infect something else in order to reproduce themselves, can move but they’re lacking the respiration, nutrition, excretion parts and therefore aren’t classed as ‘alive’.

So I said Mimi was huge, but let’s put it in context. The rhinovirus, which gives you that cold that you might be snuffling away on right now, is around 30nm in diameter. So is poliovirus. Varicella zoster virus, the thing that gave you chickenpox as a kid (or as an adult if you were really unlucky) is 150-200nm in diameter. H1N1, the virus everyone is terrified of at the moment is around 120nm. And human immunodeficiency virus is also about 120nm. These are classed as large for a virus. (Consider a nanometre is 10^-9 of a metre)

So think about Mimi again. Because this virus has a capsid of 400-500nm in diameter, with fibres spreading out from it extending 750nm. She’s a monster.

Mimi has around 1.2million base pairs in a double stranded genome. Polio’s genome is 7500 nucleotides. We managed to decode the genome and found potentially 911 sequences that could code for proteins. Human influenza codes 11. For a virus, she’s incredible.

But it doesn’t even stop there because there were proteins in there that we were interested in due to similarities to genomes we could recognise. Mimi has genes that relate to translation, metabolic pathways, DNA repair and protein folding. All of the kind of things you would expect in a living organism. Mimi still lacks ribosomes and therefore needs a host to carry out translation, but the genes are there and she’s caused a lot of excitement. Because we could have an indication that this virus is alive. And that could change microbiology as we know it.

Now, woah, we’ll hold our horses here because it’s never been proven. In fact, no one really knows quite what to make of these viruses. Maybe the virus simply picked the genes up from horizontal gene transfer in the past or maybe it lost some genes when it became host-dependent. Just the fact they’re there is incredible enough.

That’s not all, though. Because Mimi (and Mama) have other indications of life. In 2008 something else was discovered inside an Acanthamoeba. Roughly 50nm long and multiplying in amoebas where the Mamavirus (the newly crowned biggest virus in the world) was present, step up Sputnik. The first satellite virophage ever discovered.

Virophage literally means ‘virus’ and ‘eat’. This virophage is basically preying upon another virus in order to reproduce. Sputnik gets inside the Mamavirus, hijacks the proteins and translates itself whilst at the same time causing Mama to produce ineffective copies of itself and preventing death of the amoeba.

Why?

Everything is in a state of balance in life. Or at least it should be. We, as humans, upset this balance by being ‘clever’ (or destructive?) and changing our surroundings to suit us rather than the other way around. The best theory scientists have to explain this is as follows.

But imagine this didn’t occur and we had a normal food chain of plant < herbivore < carnivore. Now, if there are a lot of plants, the herbivores will move in and eat the plants and the balance will be restored. If there are a lot of herbivores and they’re eating off the plants, they’ll die but so will the plants. So the carnivores come along to eat the herbivores. Too many carnivores and the herbivore numbers are kept down but the carnivores will also starve; but this is good for the plants. Etc.

Now, starvation isn’t the only reason for death. Disease is also prevalent. So bacteria can affect plant numbers, herbivore numbers and carnivore numbers, causing weakness and death by natural selection. But this can mean bacteria numbers are overgrown and they’re not as easy to kill – living off little and possessing the ability to survive harsh conditions and adapt and reproduce quickly.

And so along comes the bacteriaphage virus, and this keeps down some of the numbers of bacteria by hijacking it to reproduce numbers of itself. But then, if there are too many viruses, something needs to be introduced naturally (not by Dettol) to kill the virus, and what better than a virophage?

Alive?

Now this doesn’t answer the question of whether or not this makes a virus more living than we have previously believed.

The lack of metabolism is what first caused scientists to think they weren’t, but defining ‘alive’ is a lot harder than the simple thing that’s taught in school. We can see things as alive that may lack one or two of the characteristics and things as dead that may possess some. So this complicates things.

Viruses can evolve (look at colds and flu – they change on at least a yearly basis. Remember, you can’t catch the same cold twice, but how many people have experienced more than one in a single winter?) and passing on their genetic information to offspring plays a major part in evolution. Now how many things that aren’t alive evolve? Just one? And that’s a virus.

But on the other hand, viruses could do none of the criteria for living without a host to bring it about.




posted on Aug, 31 2012 @ 11:42 AM
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So what about tapeworms? Tapeworms are long worms that live in your digestive tract, absorbing nutrients as food is being digested and growing the tail in segments, each with its own digestive tract and a reproductive tract, which can eventually break off into “eggs” or “immature tapeworms” that are excreted in the faeces and can be passed on. They themselves have male and female reproductive parts and there’s an argument that what we see as ‘one’ tapeworm is in fact a colony and true asexual reproduction is rare. But this is off the point. They reproduce independently, but, without the host for the nutrients, it wouldn’t manage to and it would die. The only difference between a tapeworm as a parasite and a virus as a parasite is that the worm has the capability to metabolise on its own once it has the nutrients that we provide it.

And so we’re back to metabolism. Which seems to be becoming the main sticking point for arguing that a virus could be seen as living.

But the question is whether our definition is wrong or whether the virus itself isn’t alive and is something different? In which case – what is it? Just a virus? Should it have a classification all of its own?

Or, should the Mimi and Mama viruses themselves have their own classification away from other viruses? Because it’s these guys who have the extra things in them blurring the line, not every single one of the viruses that we’ve ever discovered.

Although I doubt that a virus will be discovered to be ‘living’ or a definitive definition of life will come about in the near future because, really, other than people like me who are interested it’s not one of the pressing matters in the world like now, it’s an interesting debate to consider and one I’m pretty sure I’ll keep annoying people in the pub with for years to come.

Thanks for reading!
Ay

References

www.nature.com...
www.virology.ws...
serc.carleton.edu...
en.wikipedia.org...
www.freerepublic.com...
• Michael Brooks – 13 Things That Don’t Make Sense



posted on Aug, 31 2012 @ 11:50 AM
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Basically, there is no universal definition that I'm aware of which encompasses, and only so, what we generally perceive to be living. There's a grey area where we will simply disagree from observer to observer. Viruses fall into that category.

My question is: how does non-life give way to life? ...the extension being: at what point does non-life become living? We don't have a good answer for these questions.



posted on Aug, 31 2012 @ 11:53 AM
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Viruses are composed of a complex sugar delivery capsule and within is a RNA strand which seeks to bind to the polymerase within the cell membrane for replication and production.

This is sort of like the question when does a zygote becomes life....at what point does enough of these infected cells work together to be classified as life..?


I am not a doctor dammit
but i will offer my nonesensical opinion
edit on 31-8-2012 by MDDoxs because: (no reason given)



posted on Aug, 31 2012 @ 12:03 PM
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reply to post by Ayana
 


If it is not alive then what are they doing when they say they kill a virus?

I don't understand much of what you said, but it seems that the type of parasite that can be dormant until the correct carrier comes along is like a virus and of course it is alive?



posted on Aug, 31 2012 @ 12:06 PM
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reply to post by Char-Lee
 


That's a good point. We use "kill" as a broad term, but it's not possible to kill something that's not alive so we can't kill viruses, but it's still possible to destroy one.

That's another point that I could have added in but didn't actually think about.




posted on Aug, 31 2012 @ 12:06 PM
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Of course most biologist claim they're not, but here is my reasoning to why they are. Their classifications as to why they're not living, such as the viruses' ability to sustain homeostasis, that's where I think the definition falls apart. In order for you, a human, to sustain homeostasis you must be in an environment where the body can do so. That is of course the earth. Without our environment none of us could undergo homeostasis. The same applies to viruses. Alone they're dormant, but in the right environment, such as the human body, they too can engage in homeostasis. So basically, virii and humans are one in the same. Furthermore, I would wager humans are a virus on the earth.



posted on Aug, 31 2012 @ 12:07 PM
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reply to post by MDDoxs
 


Nah, again, it's something we don't really understand and so we can't really classify. In scientific terms you tend to be told that a virus isn't alive but a lot of evidence is to the contrary. I'd quite like someone just to go, look, it's alive/not alive. Then I wouldn't spend so much of my time dwelling on it.

In fact, I could be that person!





posted on Aug, 31 2012 @ 12:10 PM
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reply to post by PatriotAct
 


Well yeah, exactly. Everything flourishes in the right environment and a virus will adapt to it's environment the same as everything else. The main issue is the fact that the virus itself can't metabolise. But considering mitochondria are considered to be 'foreign' organelles inside of us anyway you could argue at one point the cells we were weren't alive and something else caused us to come alive the way we cause viruses to come alive.



posted on Aug, 31 2012 @ 12:11 PM
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Woo Microbiology!!!



posted on Aug, 31 2012 @ 12:13 PM
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reply to post by Ayana
 


Agreed.

Again not being an expert i can only offer my opinion. My opinion is that Viruses as we know them are not alive, but a result of them can cause future growths and trigger evolutionary changes which in turn can become some form of life.

I to agree that they share many similar characteristics with life such as their need to reproduce, but i guess it could be a matter of context. Are you looking at the individual virus vessel, or the larger mechanism as a whole.

My example.

Our brains have many nurons, on their own they dont really do that much except for producing a electrical impulse, but together our nurons give our bodies life and in conjuction with one another it forms a conciousness.

Is it the same for Viruses who knows


EDIT: THis almost becomes a philosophical question. Will robots be termed alive in the future when they can directly replicate our bodily functions and so forth.

I can feel my mind expanding
edit on 31-8-2012 by MDDoxs because: (no reason given)



posted on Aug, 31 2012 @ 12:13 PM
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Viruses are just itsy bitsy little moon landers that were created by mother nature to control the population of people. They could be engineered robotic devices made by aliens also.



posted on Aug, 31 2012 @ 12:14 PM
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reply to post by luciddream
 


They are the coolest things EVER! Hahaha. It's just such a brilliant control mechanism for something that has no real way of control.

Since you have a BSc: Do you think every virus has a virophage that we just haven't discovered yet or just the big ones like I mentioned? I'd love to do some digging and try to find out, but it's pretty difficult. We only do pathogenic stuff and replication and life cycles and that in our course.

Ah, I love microbiology so much. I'm a pharmacy student but every year we do a module on microbiology and I wish we got to do more of it! Everyone else hates it but I proper love growing stuff like that.



posted on Aug, 31 2012 @ 12:16 PM
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reply to post by luciddream
 


I bet that is an interesting job sometimes. To see how the smallest of lifeforms react to different situations. I suppose it could get boring if you let it also.



posted on Aug, 31 2012 @ 12:18 PM
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I was always taught that virus's are a sort of starting life form (much like an amoeba sort of level). It is the crossroads of a living being meets self replicating organic machines of nature.

I would say they are alive due to its ability to reproduce and adapt on its own (by on its own meaning we didn't invent it and code it, it naturally evolved to do that. Humans do the same in regards to "infecting" others to reproduce..sperm hits egg and alters egg, etc)



posted on Aug, 31 2012 @ 12:24 PM
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reply to post by SaturnFX
 


Brilliant image



posted on Aug, 31 2012 @ 12:27 PM
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reply to post by Ayana
 





Do you think every virus has a virophage that we just haven't discovered yet or just the big ones like I mentioned?


If i were to compare them to bacteriophage, i would say yes, they have been cleverly hiding as a bacteria, just like how Mamavirus did. I have to adit, Virophage is not a big subject, our lab mainly studied life cycles on T4 bacteriophage and their Lytic and Lysogenic cycles.




i'm a pharmacy student


i actually work in a pharmaceutical lab, in the microbiology section, even tho i'm just an assistant level, i do help the senior microbiologist (damn PhDs!). Sad thing is, i can't really do much clinical research here, so can't really play around like i did in school. The main test they do here is Microbial Limit, Antibiotic Assay and Preservative Challenge, they might sound familiar to you. And the stomach/intestinal flora's reaction to test drugs.
So mainly, Staph, Strepto, Pseudomonas, Ecoli and Salmonella.

Electron Microscope are awesome! Expensive to use but awesome!



posted on Aug, 31 2012 @ 12:30 PM
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Originally posted by rickymouse
reply to post by luciddream
 


I bet that is an interesting job sometimes. To see how the smallest of lifeforms react to different situations. I suppose it could get boring if you let it also.


Biology, and especially Microbiology is fun... i started doing Chemical engineering... but dropped it after first years.. its full of calculation.... no fun...

Working with living things is much more fun,...in chemistry you can expect the result thru a calculation, microbiology, everything is a surprise(to an extent)
!



posted on Aug, 31 2012 @ 12:36 PM
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reply to post by luciddream
 


Coz, yeah, it got me thinking that if certain viruses have them then why wouldn't they exist for all. But viruses themselves are so tiny the virophages on something like, even the rhinovirus would be tiny and I guess, like you said, they're not a big deal so we aren't really looking for them.

Ever think if we could find them and change them like we hijack viruses that we could make some incredible anti-viral medicines though?

Yeah, that's mainly the kind of things we do. We did some aseptics stuff this year in the special lab with the laminar flow cabinets and the whole white suit thing to see if we could manage to transfer some stuff and make solutions up without contaminating them which was kinda cool (but claustrophobic) and we've done a lot of inoculation and growth of plates and incubating things correctly to get identification or gram +ve and -ve stuff and to see the different types. We've done a lot on the microbial limits according to the BP and stuff too. It fascinates me but everyone else seems to find it boring. We did an air sample under the stairs outside of the lab and the amount of fungi we got... Wow, it covered the entire plate and there were so many different types there. I had a field day. Everyone else just found it gross. I was bouncing up and down like a kid at Christmas
. I'm so in the wrong field.

Your job sounds cool though. I've thought about going into that sort of thing once I qualify. Less money, but I think it'd be more interesting than handing out drugs in a shop. Either that or I want to go into psychopharmacology. But I've mentioned that to people and they just make Scarecrow jokes...



posted on Aug, 31 2012 @ 12:42 PM
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reply to post by luciddream
 


I've been studying the interaction of foods and many organic and inorganic chemicals and mineral complexes with the mind and body. I think it's very interesting. Many foods have psychotropic effects and others can cause imbalances that can cause irrational thinking. I have a hunch that the big chemical companies are making people doped up and other medical and pharma entities are spreading rumors to make people overeat certain foods so they create conditions in people so they can profit from fixing them. I can't believe that these organizations don't know about what they are doing, there is so much research counteracting these rumors.





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