Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Water drop holds a trillion computers

22.11.2001


Devices with DNA software may one day be fitted into cells.


DNA has problem-solving power.



"If you wear the right glasses, a lot of what you see inside the cell is computation," says Ehud Shapiro of the Weizmann Institute in Rehovot, Israel. Now Shapiro and his colleagues have turned the computational power of biological molecules to their own ends1.

The researchers have built a machine that solves mathematical problems using DNA as software and enzymes as hardware. A trillion such biomolecular machines - working at more than 99.8% accuracy - can fit into a drop of water.


Computers with DNA input and output have been made before, but they involved a laborious series of reactions, each needing human supervision. The new automaton requires only the right molecular mix.

It’s too early to say whether biomolecular nanomachines will ever become practical. Optimists, including the new machine’s inventors, envision them screening libraries of DNA sequences, or even lurking inside cells where they would watch for trouble or synthesize drugs.

The new invention is "an interesting proof of principle", says Martyn Amos, a bioinformatics researcher at the University of Liverpool, UK. Amos questions whether molecular automata could ever do anything complex enough to be useful, but thinks they may find applications inside cells.

"DNA computing needs to establish its own niche, and I don’t think that lies in competing with traditional silicon devices," says Amos. Biological computers would be better suited to biological problems, such as sensors within organisms or drug delivery, he believes.

"In 10 years this sort of computational device may be yielding applications that people pay money for," Amos says.

Already Shapiro has patented a design for a molecular computer that can perform any calculation. "If you look at the mechanisms of a cell, you could easily create a universal computer," he says. "We don’t need to teach the cell new tricks, we just need to put the existing tricks together in the right order."

Cut and paste

The new molecular computer’s input is a DNA strand. Its letters represent a string of binary symbols - ones and zeroes. The machine answers questions such as whether the input contains an even number of ones.

The computer’s hardware is two enzymes. One cuts the DNA strands when it recognizes a specific sequence of letters, another sticks DNA snippets back together again. The cutting enzyme makes incisions a few bases shy of its ’recognition sequence’. So its cuts create a range of different DNA molecules, depending on what surrounds the recognition site.

The researchers program each problem by designing DNA software molecules that bind only to a subset of the slices of input DNA. Each software molecule contains a recognition site for the cutting enzyme, and some other DNA letters that determine where on the shortened input molecule the next cut occurs.

The enzymes chomp their way along an input molecule until the calculation is complete - like an early computer processing data encoded on a paper tape. Finally, the joining enzyme attaches one of two output DNA molecules, ending the sequence of reactions and representing the answer to the initial question - yes or no, for example.

"It works better than anything I’ve seen, by far," comments Eric Baum, a computer scientist at the NEC Research Institute, Princeton, New Jersey. Baum is sceptical whether DNA computers will ever become useful. "But this is a step in the right direction," he says.

References

  1. Benenson, Y. et al. Programmable and autonomous computing machine made of biomolecules. Nature, 414, 430 - 434, (2001).

JOHN WHITFIELD | © Nature News Service
Further information:
http://www.nature.com/nsu/011122/011122-11.html

More articles from Information Technology:

nachricht Underwater acoustic localization of marine mammals and vehicles
23.11.2017 | IMDEA Networks Institute

nachricht NASA CubeSat to test miniaturized weather satellite technology
10.11.2017 | NASA/Goddard Space Flight Center

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Underwater acoustic localization of marine mammals and vehicles

23.11.2017 | Information Technology

Enhancing the quantum sensing capabilities of diamond

23.11.2017 | Physics and Astronomy

Meadows beat out shrubs when it comes to storing carbon

23.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>