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Lakeshore
An author of no particular popularity

Jay Lake
Date: 2007-05-21 19:54
Subject: [links] Link salad, lite snack edition
Security: Public
Tags:funny, links, photos, science, tech, weird
Japanese scientists use bacteria to store data — I used this conceit in my novella "The Murasaki Doctrine" (in Greetings From Lake Wu) as well as my unpublished novel The Murasaki Doctrine.

Hours of Darkness — A collection of nighttime and low light photography. Having been present at a total eclipse of the sun, I think it would be intensely cool to travel to eclipses to photograph people, animals, buildings and landscape during totality.

Incident at Toshi StationStar Wars fan film...sort of...about the perils of parking your Imperial walker at the mall.
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User: dsgood
Date: 2007-05-22 04:52 (UTC)
Subject: (no subject)
The basic idea of using genetic material to store information was first used that I know of by Philip K. Dick in "The Preserving Machine" (1953).
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User: ex_frankwu
Date: 2007-05-22 06:20 (UTC)
Subject: (no subject)
Yeah, well, the idea of storing information in DNA is all well and good, except for, well, the bad mutations. DNA which actually encodes things (proteins, binding sites where other proteins bind) has a sequence which is generally "conserved" (doesn't change from generation to generation, because chances are, if it changes, that's bad). But DNA that doesn't encode for anything (and it'd be hard to tweak a sequence of information you're storing to encode anything - like having it pull double duty - like asking a set of information to be tell an award-winning story AND be a useful computer program) - DNA that doesn't encode anything tends to accumulate mutations, at a rate of 1 per one million replications. Thus, if you have a sequence of 1 million basepairs, if you copy it several times, you'll average one mutation every time you copy it. (I may be recalling the mutation rate wrong - it may actually be 1 in 10 million.) Bacteria reproduce at a rate of once every 20 min (under ideal conditions), so you pretty quickly build up mutations where you don't want them. (The E. coli genome, which is pretty average, FYI, is about 4.5 billion basepairs).

So... over a million years, you're likely to have accumulated lots of mutations in your original sequence.

Of course... there are bacteria that could conceivably survive over 1 million years. Bacillus (gram-positive rods) bacteria, in the absence of food and water, form endospores, which are kind of like inert seeds - the endospores are impervious to burning, boiling, etc. (some have been found viable afte centuries - bacillus species include things like Bacillus subtilis, a common soil bacteria, and Bacillus anthracis, which causes anthrax). So... you could load your DNA sequence into bacillus bacteria and just dry them out - if you freeze-dried them, you'd have a pretty good chance that at least some (you'd only need one) would survive after a million years. (A vial of bacteria contains a lot - 10 x 10^8 bacteria per ml - even if your death rate was 99.99999% there would still be enough left to grow more (all you need is one).
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