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Shadpool t1_irlyr8w wrote

Reply to comment by joozwa in What lifeform has the shortest genetic sequence? by teafuck

Viruses have no need to metabolize. They use the host’s guanosine/adenosine triphosphate to power itself. Environmental adaptations such as erosions by the river are passive changes, whereas the intake of ATP/GTP by the virus is active and deliberate.

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Algorythmis t1_irlyxef wrote

Do they power themselves though? Aren't there viruses that barely shove their RNA into the host and wait for things to happen?

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Cassius_Corodes t1_irmi8m0 wrote

I personally don't see it much different to eating an animal. You are just taking someone else's energy and materials and using it for your ends. I feel the divide is mostly due to our own bias to somehow see how we get our energy and materials as somehow more worthy.

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AedemHonoris t1_irnbnat wrote

Deliberately though. When an animal (collection of interworking and specialized eukaryotic cells) eats, it is doing so based on very specific chemical and physical signals. It's not that viruses are worthy, it's that they are aimless and directionless in their "existence". A prokaryote moving towards chemical signals and changing gene expression to consume nutrients to further purposefully divide is not the same a virus that happens to have the right configuration of proteins and genetic information to attach randomly to whatever has the correct antigen to allow for assimilation and replication.

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joozwa t1_irmlex1 wrote

Virus is a handful of molecules that in a certain environment tend to react physico-chemically as the chemical structure and properties of molecules dictate. If you deem it as an "active and deliberate" you'd have to consider every chemical reaction as active and deliberate. By this definition, a catalytic converter in your car is alive.

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AedemHonoris t1_irnay9e wrote

I think the biggest thing is viruses don't react to their environment in how prokaryotes and eukaryotes do. The latter can change gene expression to interact with their environment and even move deliberately (bacteria moving towards chemical signals and then changing membrane proteins to interact with their environment). Viruses just float around, like how atoms flow with little direction and can interact with what's around them the same as 2 hydrogen molecules can interact with an oxygen molecule.

I don't consider viruses or prions alive anymore than I do proteins or atoms.

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joozwa t1_irnisdx wrote

Indeed, there's much more going on in biological systems than just merely a replication. There's both anabolic and catabolic reactions, and compartmentalization allowing for these reactions in the first place. There are different receptors acting as an input signals that influence the aforementioned reactions. Viruses lack all of that, including arguably even replication, which they can't do by their own. There's not even any spectrum here - viruses don't have any biochemistry, and even the simplest bacteria or archea exhibit all of the processes mentioned.

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se_nicknehm t1_irmafq5 wrote

seems like viruses only have a highly specialized 'environment' they need to live in and have a very short individual lifespan

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Solesaver t1_irnox24 wrote

>They use the host’s...

No they don't. That would imply that they did something. A host encounters a virus and makes copies of it. The virus does nothing. We do everyone a disservice every time we imply a virus has any agency.

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