9873210 wrote:stevensfo wrote:9873210 wrote:stevensfo wrote: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