Navigation Links
Designer piercings: New membrane pores with DNA nanotechnology
Date:11/4/2013

A new way to build membrane-crossing pores, using Lego-like DNA building blocks, has been developed by scientists at UCL, in collaboration with colleagues at the University of Cambridge and the University of Southampton.

The approach provides a simple and low cost tool for synthetic biology and the technique has potential applications in diagnostic devices and drug discovery. The research is featured in the current issue of the journal Angewandte Chemie.

Membrane pores are the gateways controlling the transport of essential molecules across the otherwise impermeable membranes that surround cells in living organisms. Typically made from proteins, pores of different sizes control the flow of ions and molecules both and in and out of the cell as part of an organism's metabolism.

Our understanding of membrane pores comes both from the study of both natural pores, and from equivalent structures built in the lab by synthetic biologists. But synthetic proteins are notoriously difficult to handle due to the complex and often unpredictable ways in which their structures can fold. Even minor protein misfolding changes a protein's properties, meaning that building synthetic pores out of proteins can be risky and time-consuming.

A more straightforward approach is so-called 'rational engineering' using Lego-like DNA building blocks. Although generally known as life's genetic code, DNA strands, which are chemically much simpler than proteins, are far easier and more predictable to work with than proteins. As such they are a useful material for building nanoscale structures in the lab.

"DNA is a construction material that follows very simple rules", said Dr Stefan Howorka (UCL Chemistry). "New nanostructures can be easily designed using a computer programme, and the elements fit together like Lego bricks. So we can build more or less whatever we like."

Using this approach, the team built a tiny tube measuring just 14 nanometres along and 5.5 nanometres across (around 10,000 times smaller than the width of a human hair). This formed the main part of their artificial nanopore. However, to insert the tube into a cell membrane, a key challenge had to be addressed: the water-soluble DNA-based structure will not embed itself into the greasy membrane which is composed of lipids.

To overcome this, the scientists chemically attached to the DNA tube two large anchors, made of molecules which have a natural affinity for lipids. These structures were then able to embed the tube into the membrane. These structures, which are based on naturally derived porphyrins, were designed by a group led by Dr Eugen Stulz (University of Southampton).

"Porphyrin molecules have ideal characteristics for our purposes," Stulz explains. "They are a strong membrane anchor, which locks the nanopore securely into the lipid membrane. In addition, they are fluorescent, which means they are easy to see and study. This makes them superior to other technologies."

The pores were characterised with electrical and fluorescence measurements in collaboration with Dr Ulrich Keyser (Cavendish Laboratory, Cambridge).

The simplicity of self-assembling a structure with only two anchors (previous studies used 26 or even 72 such anchors) greatly streamlines the design and synthesis of nanopores.

"In future, this new process will enable us to tailor DNA nanopores for a much wider range of applications than are currently possible," Keyser says.

The ability to create synthetic channels through lipid membranes enables numerous applications in the life sciences. In the first instance, DNA nanopores are of great interest for biosensing, such as rapid DNA analysis.

But tailored pores can also be expected to aid the development of new drugs. Prototype drugs are typically designed to affect a biological target, but are not engineered to cross the cell membrane. Self-assembled pores provide a route for drugs to pass into cells, allowing for much faster pre-clinical screening for activity.


'/>"/>

Contact: Clare Ryan
clare.ryan@ucl.ac.uk
44-020-310-83846
University College London
Source:Eurekalert

Related biology news :

1. Molecular biology: Designer of protein factories exposed
2. Finland to lead the way as a designer of cellulose-based products
3. Designer bacteria may lead to better vaccines
4. Biologists engineer algae to make complex anti-cancer designer drug
5. University of Albertas designer compounds inhibit prion infection
6. African scientist, designer partner to fashion anti-malaria garment that wards off bugs
7. Super-thin membranes clear the way for chip-sized pumps
8. Researchers capture images of open channel that moves proteins across cell membranes
9. Study: Acidity can change cell membrane properties
10. How bacteria integrate autotransporters into their outer membrane
11. Photosynthesis: Membranes in tight corners
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/21/2016)... British Columbia , June 21, 2016 /PRNewswire/ ... appointed to the new role of principal product ... been named the director of customer development. Both ... NuData,s chief technical officer. The moves reflect NuData,s ... teams in response to high customer demand and ...
(Date:6/9/2016)... , June 9, 2016  Perkotek an innovation leader in attendance control systems is ... log work hours, for employers to make sure the right employees are actually signing ... http://photos.prnewswire.com/prnh/20160609/377486LOGO ... ... ...
(Date:6/2/2016)... The Department of Transport Management (DOTM) ... million US Dollar project, for the , Supply ... Enrolment, and IT Infrastructure , to ... implementation of Identity Management Solutions. Numerous renowned international vendors participated ... was selected for the most compliant and innovative ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... ... June 24, 2016 , ... Researchers at the Universita ... miRNAs in people with peritoneal or pleural mesothelioma. Their findings are the subject of ... now. , Diagnostic biomarkers are signposts in the blood, lung fluid or tissue ...
(Date:6/23/2016)... 2016 /PRNewswire/ - FACIT has announced the creation ... biotechnology company, Propellon Therapeutics Inc. ("Propellon" or "the ... a portfolio of first-in-class WDR5 inhibitors for the ... WDR5 represent an exciting class of therapies, possessing ... for cancer patients. Substantial advances have been achieved ...
(Date:6/23/2016)... 2016  The Prostate Cancer Foundation (PCF) is pleased to announce ... cures for prostate cancer. Members of the Class of 2016 were selected from ... Read More About the Class of 2016 PCF Young Investigators ... ... ...
(Date:6/23/2016)... ... 23, 2016 , ... STACS DNA Inc., the sample tracking software company, today ... Laboratory, has joined STACS DNA as a Field Application Specialist. , “I am ... and COO of STACS DNA. “In further expanding our capacity as a scientific integrator, ...
Breaking Biology Technology: