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A couple little "Sputnik" viruses seen as green blobs infect part of the bigger mamavirus, which is the big red blob.  (Source: La Scola, B. et al. Nature doi:10.1038/nature07218 (2008)

Big viruses may be an integral, and perhaps living, part of the ocean plankton ecosystem which impacts both the entire ocean and the global climate.   (Source: J. SCHMALTZ/NASA)
Looks like viruses can catch colds just like the rest of us

One of the fundamental questions in science is "what is life?", a question particularly pertinent of late with the search for signs of life on Mars and the advances in developing synthetic life in a lab.  Scientists have devised many complex answers to the question, but basically most scientists would agree that a "living" creature must be able to produce a variety of useful structural units (proteins), carry a genetic code (DNA), and reproduce.

Following this definition of life, viruses typically met the latter two tests, but failed the first as they only produced a few structural or protective proteins to encase themselves.  This was a primary justification in classing them as nonliving.  However, recent discoveries have troubled this comfortable notion of the solid boundary between life and nonlife.  First, a variety of parasitic bacteria have been discovered, many of which lack the key protein enzymes needed to survive outside their host -- another bacteria.

Also, giant viruses have been discovered, which in addition to infection related proteins, make a variety of other proteins which help it carry out other processes.  On a level of complexity they can surpass the microbacteria, but they're clearly related to other much smaller viruses.

Now a new piece of evidence supporting that viruses may be somewhat "alive" has been added -- viruses can catch a virus. 

The discovery began more than a decade prior when researchers found a massive parasite in an amoeba from a cooling tower in Bradford, UK.  The little creature was frozen, as it was thought to be run-of-the-mill parasitic bacteria.  However, upon closer inspection, years later the scientists recognized it as a virus, with a gigantic genome, capable of encoding over 900 proteins.  The virus was named Acanthamoeba polyphaga mimivirus (for mimicking microbe).  It was over three times bigger than any previous virus. 

The discovery brought great excitement to some nontraditional biologists who had long believed viruses to be living.  Says Eugene Koonin of the National Center for Biotechnology Information in Bethesda, Maryland, "It was the cause of great excitement in virology.  It crossed the imaginary boundary between viruses and cellular organisms."

Now Professor Koonin, Jean-Michel Claverie, a virologist at the CNRS UPR laboratories and Didier Raoult at CNRS UMR, made an even more shocking discovery.  The team in 2003 discovered an even bigger virus.  They named this one mamavirus.

The shocker came when they found that a smaller virus with just 21 genes was associated with the new mega-virus and was infecting it.  While the main virus infected the amoeba, hijacking the amoeba's enzymes and structure to make a protein factory, the tiny virus, which researchers named "Sputnik" set to work hijacking this factory and making copies of itself.

The result was the mamavirus got more than just a bad cold -- it produced fewer and deformed mamaviruses, effectively making it less infective.  This relationship of a viral parasite sickening a host is one only expected by something living, further evidence that the big viruses might be "alive".

Says Jean-Michel Claverie on the mamavirus, "There’s no doubt this is a living organism.  The fact that it can get sick makes it more alive."

Mr. Koonin adds, "It infects this factory like a phage infects a bacterium.  It’s doing what every parasite can — exploiting its host for its own replication."

Intriguingly the little virus has genes similar to those used by the mamavirus and mimiviruses for reproduction.  This leads some researchers to speculate the virus could have been created by a failed reproduction by the big viruses.  This also supports the idea of the big viruses as being alive, as a prevalent theory for the origin of viruses was that they came from misreplicated bacterial DNA.  Further the little virus can transform genes between big viruses, similar to horizontal-gene-transfer in bacteria.

The new finding may have a big impact on global biology.  In plankton blooms genetic sequences have been found similar to those in the big viruses.  These blooms may be teaming with big viruses, which would likely have been destroyed by sample collectors' bacterial filters.  By impacting the life and death of plankton the big viruses could impact not only ocean nutrient cycles, but the global climate itself. 

Curtis Suttle, an expert in marine viruses at the University of British Columbia in Vancouver states, "These viruses could be major players in global systems.  I think ultimately we will find a huge number of novel viruses in the ocean and other places.  It emphasizes how little is known about these organisms — and I use that term deliberately."

The full study on the topic of large plankton viruses can be viewed here, while the study on the mamavirus can be viewed here.



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RE: More evidence
By wgbutler on 8/8/2008 10:01:13 AM , Rating: 2
Yeah, I was wondering how long it would take for the anti-Christian comments to start showing up. It's interesting that JonnyDough singled out Christianity in his attack when in fact three of the world's major religions (Judiasm, Islam) basically all have the same belief. In fact, Christianity got its beliefs on creation directly from Judaism. So why doesn't JonnyDough say, "if any JEW has a better explanation" etc etc, hmmm??

At any rate, people who want to belief that the universe somehow created itself with all the constants in physics precisely fine-tuned to support life, and after that lightning struck a mud puddle billions of years ago and created all life on earth are more than welcome to believe that way, as far as I'm concered. I think its pretty stupid personally.


RE: More evidence
By William Gaatjes on 8/8/2008 7:03:48 PM , Rating: 2
Well, I am sure at some point in the past there was some truth to the original scripts. But every single religious book has been rewritten to the needs of the ones in charge centuries ago. And every religion after that partially copied the religions known at the time. And the jews in ancient times had many relegions, not one unified religion.
At that time there where many tribes fighting with eachother.

Religion is a very powerfull tool. And it is not as if humans where not intelligent 2000 years ago or way more back in time.
Good understanding of the human psyche has been around for ages. Religion can give hope. But that hope can be abused. And that is what happening at any day in time.
Hope gives us drive...

You might want to do some research into physics. You will find that the seeds of life are not created 6000 years ago.
You will find out that the seeds of life and being/soul whatever you might call it did not enter our universe during the big bang. It is our universe. But it is not as you wil find in the holy books. No man like god figure we resemble. Just a drive to exist and to be. That's it...


RE: More evidence
By JonnyDough on 8/9/2008 7:39:50 AM , Rating: 2
The reason I picked on Christianity is because it is the largest politically and majority backed religion in the U.S. One can discount all religions that are based on God. The ones based purely on faith are the easiest to discount. Anyone can have faith on anything, and if it's emotion driven (i.e. Catholic fear and guilt) then it's easily explained as well.

At any rate, people who decide to explain the origins of life with a made up "sun God" like Jesus himself should be thrown into Hell, provided we ever find out just where the hell Hell actually is...

The only clue I have is from a 2,000 year old book written by political leaders under persecution. It seems to be in the center of the earth...something about a hot pit. Interestingly enough, some early Christians were known to throw people into fiery pits that didn't agree with their religion. Hmm.

From a scientific standpoint what you described with lightning and all that sounds more believable than a God that will damn you to hell for not believing in him, yet he is our creator and loves us. Oh, and he's all powerful and all knowing and all seeing but his temple needs our money. Sue me for trying to be logical instead of basing my theories on unprovable old superstitions and claiming them as fact.


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