A Truly Alive Virus

cyclop writes "Microbiologists are puzzled by the genome sequence of the giant Mimivirus. It seems this virus has even more genes than many bacteria, is able to synthesize its own proteins and therefore is, by definition, alive. 'We are seeing an organism here. There is DNA, RNA and plenty of proteins,' says Didier Raoult, who reports the work in this week's Science."

Comments

Um, no....

[slowtech]

Having DNA coding for a lot of proteins does not make a virus alive. This virus has a lot of DNA (the poxvirii do as well), but that does not mean it has a metabolism. Virii use their host's metabolism to produce proteins.

Whether you think virii are alive or not, there is nothing about this virus that suggests (from the linked PubMed abstract) that this virus is qualitatively different from any other.

Size?

[tod_miller]

I thought the amount of genes didn't matter (could be junk genetics?)

Remember the Macro-virus on Voyager? [IANAT]

I didn't realise that Viruses weren't 'alive'...

Since the 1960s, scientists have argued about whether viruses are living organisms or just a bundle of very large molecules.

aaaah so - definition of life...

Then the truly dumb dumb dumb stuff:

A virus has to hijack another organism's biological machinery to replicate, which it does by inserting its DNA into a host. Bacteria, on the other hand, carry all that they need to reproduce independently, and thus qualify as alive.

Well oil my ovaries, auto-reproduction [there might be a better word for it] here I come! [I am alive right?]

OK I realise they don't mean asexual reproduction is the only way of being able to reproduce on your own.

I guess some /.'ers could only reproduce by infecting someone elses DNA!! :-)

Evolution proof ?

[Jesrad]

This virus is not yet self-reproducting, but I think it might just evolve a bit more and complete that last step. It's a nice demonstration of evolution in action, I think.

Re:Evolution proof ?

[Anonymous Coward]

This virus is not yet self-reproducting, but I think it might just evolve a bit more and complete that last step. It's a nice demonstration of evolution in action, I think.


Perhaps it was once a bacterium which lost its selfreproductivity in a bid to maximize parasitivity.

Re:Evolution proof ?

[Ayaress]

Perhaps it was once a bacterium which lost its selfreproductivity in a bid to maximize parasitivity.

Evolution or not, that would have been my first guess, too, from its size and the volume of its genome. However, if that were the case, you'd expect the genes it does have to be like their equivalents in bacteria, which isn't the case. The cnrs.fr link says that it shares key gene sturctures in common with viruses like smallpox.

An interesting possibility would be that it's actually a sort of "hybrid." A mutation in the protien structure of the viral coat might cause the abnormally large size (a reduction in the bonding angles, perhaps), allowing for the fused genome of the host bacterium and the original virus, along with various key molocules from the bacterium to all be packaged into the virus, instead of just the viral DNA alone.

Hmmm DNA computer template?

[merlin_jim]

Wow this virus is self contained, has 800 kilobase pairs, can replicate its own proteins, uses a circular genome (think of a turing machine tape), and is capable of DNA self-repair, unlike every other organism in the world. And the scientists believe that over 90% of its DNA is actively used throughout its lifecycle.

Sounds like an ideal building block for a genetic computer. I'm half-seriously wondering based on that 90% figure if it is in fact the left over of some pre-historic genetic computer?

There are more mysteries here; the virus has genes common to all cellular life, but it itself is clearly not cellular. Unless this virus is a close relative of some precursor virus that initially combined with a bacteria to from the first nucelied cell, then this is an EXTREMELY improbable occurance.

I mean form follows function, but in this case the form is present but not necessarily the function... parallel evolution doesn't really explain that...

All the same, if I was a genetic computing microbiologist I'd be very interested in this guy...