Perseverance looks for life

[stevensfo]

However, having a fertile imagination, I wonder if it's possible for protein chains to play a role in storing info. There are long structural protein strands like keratin and collagen that have similar structures to DNA. Maybe on some planets, an organism uses these?

It's pretty easy to dream up schemes that can store information*. It's a bit harder to find schemes that are stable, but not too stable.
The really hard part is the mechanisms for transcription, replication and other metabolism. DNA does not replicate, cells replicate.**

* For example alternating ethylene and propylene in poly-whatever. A bit of information is stored in the presence or absence of the methyl side group. Methylation is used to store epigenetic information in DNA.

** Labs can also replicate, but is that a good basis for life?

Which may be a good model for the early earth in which RNA was the store of information and slowly switched to DNA while retaining the cell's ability to divide the DNA molecules into two new cells.

To be honest, I can't remember anything about methylation of DNA, but it's been 40 years!

Ethylene and Propylene are just ethanol (booze) and propanol (rubbing alcohol/car ice spray) with extra double carbon bonds. Don't see them having much impact on life, apart from a form of anti freeze.


Steve

You missed the "poly" part. Polyethylene and polypropylene are large alkanes with no double bonds. The names are from the manufacturing process not the chemical structure. You can encode a lot of information in the branching structure of a large alkane.

Thanks. Something else to look into while avoiding the in-laws!
Steve

[9873210]

Thanks. Something else to look into while avoiding the in-laws!
Steve

Just so I don't lead you too far down a garden path.

A search on polyethylene, alkanes etc. will turn up a lot of organic chemistry about plastics. This may be good background. Probably not too much about mixing ethylene and propylene monomers in the same polymer, but there's probably something on that since it's the sort of thing organic chemists did in the 20th Century.

It probably won't turn up much on information storage in these plastics.

I didn't invent this, but IIRC I heard it as a throwaway example during a lecture that you could store information in almost anything, in particular in any polymer built from two or more different monomers that can be in arbitrary order (which includes DNA, RNA, proteins and a lot of other long chain organic molecules.

It's like saying you can store a lot of information using chalk on the side of a barn, if the barn is big enough and you have enough chalk. Or by building the barn with red and yellow bricks to form a bar code.

Of course if you want a rabbit hole to avoid the in-laws this is as good as any.

[XFool]

I didn't invent this, but IIRC I heard it as a throwaway example during a lecture that you could store information in almost anything...

It's like saying you can store a lot of information using chalk on the side of a barn, if the barn is big enough and you have enough chalk. Or by building the barn with red and yellow bricks to form a bar code.

https://www.nasa.gov/sites/default/files/atoms/files/mars-perseverance-parachute-coding-activity.pdf

[odysseus2000]

I didn't invent this, but IIRC I heard it as a throwaway example during a lecture that you could store information in almost anything...

It's like saying you can store a lot of information using chalk on the side of a barn, if the barn is big enough and you have enough chalk. Or by building the barn with red and yellow bricks to form a bar code.

https://www.nasa.gov/sites/default/files/atoms/files/mars-perseverance-parachute-coding-activity.pdf

Yes, but it’s the life expectancy of the stored information which tells you how good of an archive one has.

Surprising seemingly fragile media in the right conditions such as the Dead Sea scrolls existed in can last over 2000 years, unless of course they are another fake.

Regards,

[ursaminortaur]

Thanks. Something else to look into while avoiding the in-laws!
Steve

Just so I don't lead you too far down a garden path.

A search on polyethylene, alkanes etc. will turn up a lot of organic chemistry about plastics. This may be good background. Probably not too much about mixing ethylene and propylene monomers in the same polymer, but there's probably something on that since it's the sort of thing organic chemists did in the 20th Century.

It probably won't turn up much on information storage in these plastics.

I didn't invent this, but IIRC I heard it as a throwaway example during a lecture that you could store information in almost anything, in particular in any polymer built from two or more different monomers that can be in arbitrary order (which includes DNA, RNA, proteins and a lot of other long chain organic molecules.

It's like saying you can store a lot of information using chalk on the side of a barn, if the barn is big enough and you have enough chalk. Or by building the barn with red and yellow bricks to form a bar code.

Of course if you want a rabbit hole to avoid the in-laws this is as good as any.

But for life you need not just to store information but to

1). Be able to extract the information and use it to construct and maintain a phenotype which with our form of life is done via proteins.
2). Be able to replicate that information.

[odysseus2000]

There is apparently at least one immortal species on Earth:

https://www.science.org.au/curious/eart ... ve-forever

The creature can effectively reverse time & become young again.

If this analysis is correct then being able to make copies of one’s self & reproduce is not a universal definition of what is needed.

There are other things like yeast that can essentially shut down & stay shut down for very long time periods in very hostile environments & then if suitable conditions return it can come back to life.

There are examples of bacteria that can live inside a nuclear reactor, where I imagine having a robust map of what the bacteria should look like is essential for the relentless repair operations.

Regards,