Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Researchers build synthetic membrane channels out of DNA: Nanotech structures mimic nature's way of tunneling through cell walls

This 3-D print shows the structure of a functional synthetic membrane channel constructed through DNA nanotechnology -- that is, using DNA molecules as programmable building materials for custom-designed, self-assembling nanometer-scale structures. This DNA-based membrane channel consists of a needle-like stem 42 nanometers long with an internal diameter of just two nanometers, partly sheathed by a barrel-shaped cap. A ring of cholesterol units around the edge of the cap helps the device "dock" to a lipid membrane while the stem sticks through it, forming a channel that appears capable of behaving like a biological ion channel. The device is formed by 54 double-helical DNA domains on a honeycomb lattice.

Credit: Dietz Lab, TU Muenchen; copyright TU Muenchen
This 3-D print shows the structure of a functional synthetic membrane channel constructed through DNA nanotechnology -- that is, using DNA molecules as programmable building materials for custom-designed, self-assembling nanometer-scale structures. This DNA-based membrane channel consists of a needle-like stem 42 nanometers long with an internal diameter of just two nanometers, partly sheathed by a barrel-shaped cap. A ring of cholesterol units around the edge of the cap helps the device "dock" to a lipid membrane while the stem sticks through it, forming a channel that appears capable of behaving like a biological ion channel. The device is formed by 54 double-helical DNA domains on a honeycomb lattice.

Credit: Dietz Lab, TU Muenchen; copyright TU Muenchen

Abstract:
As reported in the journal Science, physicists at the Technische Universitaet Muenchen (TUM) and the University of Michigan have shown that synthetic membrane channels can be constructed through "DNA nanotechnology." This technique employs DNA molecules as programmable building materials for custom-designed, self-assembling, nanometer-scale structures. The researchers present evidence that their nature-inspired nanostructures may also behave like biological ion channels. Their results could mark a step toward applications of synthetic membrane channels as molecular sensors, antimicrobial agents, and drivers of novel nanodevices.

Researchers build synthetic membrane channels out of DNA: Nanotech structures mimic nature's way of tunneling through cell walls

Munich, Germany | Posted on November 20th, 2012

Over the past three decades, researchers have advanced DNA nanotechnology from an intriguing idea to an emerging technology, with a toolbox of methods and a portfolio of nanometer-scale objects designed to demonstrate its potential. What's new here is the claim that DNA nanotech can be used to mimic one of the most widespread and important nanomachines in nature.

To wall off the insides of cells from the outside world, organisms in all three domains of life use the same kind of barrier: an impermeable membrane made from two layers of lipid molecules. Such membranes can also be found within cells, for example encapsulating the nucleus, and even surrounding many kinds of viruses. And to mediate between the different environments on either side of this universal barrier, nature provides a common type of passageway. Membrane channels are tube-like structures made of proteins, which pierce the barriers and regulate the two-way exchange of material and information between the inside and outside. Now researchers have demonstrated the first artificial membrane channel made entirely of DNA, and its characteristics suggest a number of potential applications. "If you want, for example, to inject something into a cell, you have to find a way to punch a hole into the cell membrane, and this device can do that, at least with model cell membranes," says TUM Prof. Hendrik Dietz, a fellow of the TUM Institute for Advanced Study.

In a shape inspired by a natural channel protein, the DNA-based membrane channel consists of a needle-like stem 42 nanometers long with an internal diameter of just two nanometers, partly sheathed by a barrel-shaped cap. A ring of cholesterol units around the edge of the cap helps the device "dock" to a lipid membrane while the stem sticks through it, forming a channel that appears to function like the real thing. TUM Professor Friedrich Simmel, co-coordinator of the Excellence Cluster Nanosystems Initiative Munich, explains: "We have not tested this yet with living cells, but experiments with lipid vesicles show that our synthetic device will bind to a bilayer lipid membrane in the right orientation, so that the stem both penetrates the membrane and holds at the surface, forming a pore."

Further experiments demonstrated that the resulting pores have electrical conductivity comparable to that of a natural cell wall with ion channels, suggesting that they might be able to act like voltage-controlled gates. The results also suggest that transmembrane current could be tuned by adjusting fine structural details of the synthetic channels. To test one potential application of the DNA nanotech devices, the researchers used them as "nanopores" for several different molecular sensing experiments. These confirmed that it is possible, by observing changes in the electrical characteristics, to record the passage of single molecules through synthetic membrane channels made from DNA. Because this approach allows both geometric and chemical tailoring of the membrane channels, it might offer advantages over two other families of molecular sensors, based on biological and solid-state nanopores respectively.

Other conceivable applications remain to be investigated. One notion is to imitate the action of viruses or phages, breaking through the cell walls of targeted bacteria to kill them. In gene therapy, synthetic membrane channels might be used as nano-needles to inject material into cells. Such channels could also be used in basic studies of cell metabolism. Another idea is to harness the so-called ion flux — which in cell membranes moves material in and out through the channel — to drive sophisticated nanodevices inspired by other natural mechanisms. "We might be able to mimic natural ion pumps, transport proteins, and rotary motors like the enzyme responsible for synthesizing ATP," says Dietz. "I love that idea. That's what keeps me running."
###

This work was supported by the German Research Foundation (DFG) via the TUM Institute for Advanced Study, Excellence Clusters NIM (Nanosystems Initiative Munich) and CIPSM (Center for Integrated Protein Science Munich), and SFB 863; by the Federal Ministry of Education and Research (BMBF, Grant 13N10970); by the European Research Council (Dietz, Starting Grant GA256270); and by the National Institutes of Health (Mayer, Grant 1R01GM081705).

Original publication:

Martin Langecker*, Vera Arnaut*, Thomas G. Martin*, Jonathan List, Stephan Renner, Michael Mayer, Hendrik Dietz°, and Friedrich C. Simmel°. Synthetic lipid membrane channels formed by designed DNA nanostructures. Science, vol. 338, issue 6109, pp. 932-936. DOI: 10.1126/science.1225624 (* equal contribution authors; ° co-corresponding authors)

####

About Technische Universitaet Muenchen
Technische Universitaet Muenchen (TUM) is one of Europe's leading universities. It has roughly 480 professors, 9000 academic and non-academic staff, and 31,000 students. It focuses on the engineering sciences, natural sciences, life sciences, medicine, and economic sciences. After winning numerous awards, it was selected as an "Excellence University" in 2006 and 2012 by the Science Council (Wissenschaftsrat) and the German Research Foundation (DFG). The university's global network includes an outpost with a research campus in Singapore. TUM is dedicated to the ideal of a top-level research-based entrepreneurial university.

For more information, please click here

Contacts:
Patrick Regan

49-892-891-0515

Prof. Hendrik Dietz
Technische Universitaet Muenchen
Physics Dept., Walter Schottky Institute / ZNN
Am Coulombwall 4a
85748 Garching, Germany
Tel: +49 89 289 11615

Web: bionano.physik.tu-muenchen.de/

Prof. Friedrich Simmel
Technische Universitaet Muenchen
Physics Dept., Walter Schottky Institute / ZNN
Am Coulombwall 4a
85748 Garching, Germany
Tel: +49 89 289 11611

Web: www.e14.ph.tum.de

Copyright © Technische Universitaet Muenchen

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Physicists solve quantum tunneling mystery: ANU media release: An international team of scientists studying ultrafast physics have solved a mystery of quantum mechanics, and found that quantum tunneling is an instantaneous process May 27th, 2015

Nanotechnology identifies brain tumor types through MRI 'virtual biopsy' in animal studies: If results are confirmed in humans, tumor cells could someday be diagnosed by MRI imaging and treated with tumor-specific IV injections; new NIH grant will fund future study May 27th, 2015

Who needs water to assemble DNA? Non-aqueous solvent supports DNA nanotechnology May 27th, 2015

Controlled Release of Anticorrosive Materials in Spot by Nanocarriers May 27th, 2015

Molecular Machines

One step closer to a single-molecule device: Columbia Engineering researchers first to create a single-molecule diode -- the ultimate in miniaturization for electronic devices -- with potential for real-world applications May 25th, 2015

UCLA nanoscientists are first to model atomic structures of three bacterial nanomachines: Cryo electron microscope enables scientists to explore the frontiers of targeted antibiotics April 21st, 2015

Advances in molecular electronics: Lights on -- molecule on: Researchers from Dresden and Konstanz succeed in light-controlled molecule switching April 20th, 2015

Designer's toolkit for dynamic DNA nanomachines: Arm-waving nanorobot signals new flexibility in DNA origami March 27th, 2015

Molecular Nanotechnology

One step closer to a single-molecule device: Columbia Engineering researchers first to create a single-molecule diode -- the ultimate in miniaturization for electronic devices -- with potential for real-world applications May 25th, 2015

Nature inspires first artificial molecular pump: Simple design mimics pumping mechanism of life-sustaining proteins found in living cells May 19th, 2015

Feynman Prize Winners Announced! April 26th, 2015

Surface matters: Huge reduction of heat conduction observed in flat silicon channels April 23rd, 2015

Self Assembly

Engineering Phase Changes in Nanoparticle Arrays: Scientists alter attractive and repulsive forces between DNA-linked particles to make dynamic, phase-shifting forms of nanomaterials May 25th, 2015

Scientists Use Nanoscale Building Blocks and DNA 'Glue' to Shape 3D Superlattices: New approach to designing ordered composite materials for possible energy applications April 23rd, 2015

Advances in molecular electronics: Lights on -- molecule on: Researchers from Dresden and Konstanz succeed in light-controlled molecule switching April 20th, 2015

Carnegie Mellon chemists create tiny gold nanoparticles that reflect nature's patterns April 9th, 2015

Nanomedicine

New electronic stent could provide feedback and therapy — then dissolve May 27th, 2015

Arrowhead to Present at Jefferies 2015 Healthcare Conference May 27th, 2015

Seeing the action: UCSB researchers develop a novel device to image the minute forces and actions involved in cell membrane hemifusion May 27th, 2015

Nanotechnology identifies brain tumor types through MRI 'virtual biopsy' in animal studies: If results are confirmed in humans, tumor cells could someday be diagnosed by MRI imaging and treated with tumor-specific IV injections; new NIH grant will fund future study May 27th, 2015

Sensors

Technology for Tomorrow’s Market Opportunities and Challenges: LetiDays Grenoble Presents the Possibilities: June 24-25 Event Includes Focus on IoT-Augmented Mobility and Leti’s Latest Results on Silicon Technologies, Sensors, Health Applications and Smart Cities May 27th, 2015

This Slinky lookalike 'hyperlens' helps us see tiny objects: The photonics advancement could improve early cancer detection, nanoelectronics manufacturing and scientists' ability to observe single molecules May 23rd, 2015

Record high sensitive Graphene Hall sensors May 21st, 2015

Graphene enables tunable microwave antenna May 15th, 2015

Discoveries

Advance in quantum error correction: Protocol corrects virtually all errors in quantum memory, but requires little measure of quantum states May 27th, 2015

New electronic stent could provide feedback and therapy — then dissolve May 27th, 2015

Seeing the action: UCSB researchers develop a novel device to image the minute forces and actions involved in cell membrane hemifusion May 27th, 2015

Physicists solve quantum tunneling mystery: ANU media release: An international team of scientists studying ultrafast physics have solved a mystery of quantum mechanics, and found that quantum tunneling is an instantaneous process May 27th, 2015

Announcements

Physicists solve quantum tunneling mystery: ANU media release: An international team of scientists studying ultrafast physics have solved a mystery of quantum mechanics, and found that quantum tunneling is an instantaneous process May 27th, 2015

Nanotechnology identifies brain tumor types through MRI 'virtual biopsy' in animal studies: If results are confirmed in humans, tumor cells could someday be diagnosed by MRI imaging and treated with tumor-specific IV injections; new NIH grant will fund future study May 27th, 2015

Who needs water to assemble DNA? Non-aqueous solvent supports DNA nanotechnology May 27th, 2015

Controlled Release of Anticorrosive Materials in Spot by Nanocarriers May 27th, 2015

Research partnerships

Supercomputer unlocks secrets of plant cells to pave the way for more resilient crops: IBM partners with University of Melbourne and UQ May 21st, 2015

Taking control of light emission: Researchers find a way of tuning light waves by pairing 2 exotic 2-D materials May 20th, 2015

Efficiency record for black silicon solar cells jumps to 22.1 percent: Aalto University's researchers improved their previous record by over 3 absolute percents in cooperation with Universitat Politècnica de Catalunya May 18th, 2015

Organic nanoparticles, more lethal to tumors: Carbon-based nanoparticles could be used to sensitize cancerous tumors to proton radiotherapy and induce more focused destruction of cancer cells, a new study shows May 18th, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project