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DNA as Construction Equipment
vivekb writes "Scientists at Ruhr University in Germany are using DNA to assemble microscopic structures. They attached matched DNA strands to construction materials, and use the DNA as an highly selective bonding agent. So far, basic polyhedra have been manufactured using gold spheres. The BBC presents this article. The paper is entitled Self-Assembly of Trisoligonucleotidyls. "
This is actually pretty cool.
I don't know about you guys (and girls, no sexism here), but I start thinking about other events where a discovery has led to an unexpected area of application; liquid crystals, teflon, microwaves... can anyone think of more examples? Let's hear it for abstract knowledge!
Hopefully, this will give nanotech a leg up. Using DNA for the actual enzymes and whatnot seems a little bulky to me, but you could probably use the technique to build the nanotech "factories" that are going to assemble the actual nanobots. I imagine von Neumann machines could be built with this as well... DNA is good at self-replication too =)
// Eärendil
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Paranoia is simply reality on a finer scale.
I can see it now! Micro-Lego(TM)! And it'll reproduce too! Get more for your buck, with Micro-Lego(TM)!
"There are more important things than stopping terrorism. Upholding the Constitution is one of them." - Ars Forumer.
We need people with a good overview of the field to make informed comment and separate the wheat from the chaff in areas such as biotech, which is outside of the sphere of competence of many inorganic materials-based nanotech experts.
How about creating a website devoted to such analysis? It could be a valuable resource.
"The question of whether machines can think is no more interesting than [] whether submarines can swim" - Dijkstra
The problem with building things at the nanometer scale is putting them together. We can make individual wires, transistors, bearings, shafts etc. out of atoms, but we can't put them together...
You really can't get out some tweasers and squint a bit to make a machine that will fit inside a cells nucleus.
These biotech guys have one way of organising the construction process. It is much easier to use DNA to drag prefabricated components together than to use pure chemistry to build them on site. (You need selectivity to make sure this bit gets made or put here, and not there.)
Unfortunately, I don't think this will work. DNA is just too big for the parts they are making at the moment. (The parts are made chemically - so they can only be a few hundred atoms or so before the yield drops off.) The way around this is to make successively smaller machines that can build yet smaller machines, and so on. The problem is that I don't see anyone with the blueprints for a universal constructor.
"Would you like a cold drink with that Sir? Yes, yes, for the sake, of the future, of all mankind, I will have, a sm
2. Kiedrowski is one of the guys who's research led to the discovery of rybozymes - self-modifying, RNA-based molecules, which can even in a certain way replicate themselves. RNA research is much more promissing at this point than DNA research - RNA molecules tend to have a much more complicated structure and sometimes carry enzymatic activities. It is now a widely accepted view that the life started with self-replicating and self-encoding RNA molecules. For the difference between DNA and RNA molecules only one oxygene atom is responsible, lacking in DNA (therefore, deoxyribonucleic acid). He re is an abstract of an article by Kiedrowski about self-replicating molecules.
3. Both DNA and RNA are prone to enzymes called nucleases. RNA is especially fragile - it is enough to touch the cap of a propylene tube containing RNA sample with a bare finger - and there goes a week of your research, because there are plenty of RNases (enzymes digesting RNA) on your fingers. DNA is much more stable, but still you have to store it in -20 in a buffer containing EDTA, a chemical which binds to metall iones, which are necessary for DNases to work (RNases are very hard to get rid off: boiling, cleaning with ethanol doesn't help).
4. This is an abstract of the research report written by Kiedrowski himself. English translation is lower down the page.
5. As for "velcro" properties of DNA for constructing nanobots, I have a better proposition - there is a type of synthetic molecules, which are called "peptide-nucleic acids" (PNAs). In this molecules, instead of the riboze (which is a sugar) and phosphoric acid residues, the "spine" of a moleucle consists of a pseudopeptide. In fact, PNAs are not acidic - and this is very important. When two single strand DNA molecules bind, they have to overcome the negative charge they bear. In fact, to make them do it, you have to provide sufficient salt concentration in the solution where the binding (hybridization) takes place. PNAs are not acidic => have no charge at all => can even bind in water. And they are much more stable than other nucleic acids. On this page you can find many sources of information about PNAs.
6. There are much better sources of easy-to-read, but scientifically sound articles about current research in biology and other fields - Nature Science Update - a very good site for a start, updated daily.
Regards,
January
P.S. When /. posts a reference to an article about computers, it is usually worth reading. When /. posts a reference to an article about biotech, don't bother.
Isn't the "there are things Man was not meant to know" spiel getting just a wee bit old? They said it about electricity for crying out loud...
I personally find these types of articles very interesting. Granted, they impart a Diamond Age feeling, but I think that is more of a sign of Neal Stephenson's insight rather than just sci-fi hype. (Comsat?)
The fact is nanotechnology is making great strides lately, even if only in terms of public perception(or media hype, whatever). That in itself is good. The more people become aware of what could be, the more likely people are going to start funding/supporting nanotech so that it will be. This is all relevant to Slashdot because nanotech will change computing drastically once it arrives in full force.
Since when was computing the domain of silicon only? Keep it coming.
Scarpa
oh shoo /.
disregard this
i'm just fiddling with
;-)
"I want peace on earth and good will toward men." "We're the U.S. government. We don't do that sort of thing!!"