Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Photonoic Crystal Biosensors Detect Protein-DNA Interactions

24.09.2008
Scientists at the University of Illinois have developed a new class of disposable, microplate-based optical biosensors capable of detecting protein-DNA interactions.

Based on the properties of photonic crystals, the biosensors are suitable for the rapid identification of inhibitors of protein-nucleic acid and protein-protein interactions.

“Protein-DNA interactions are essential for fundamental cellular processes such as transcription, DNA damage repair and apoptosis,” said Paul Hergenrother, a professor of chemistry and an affiliate of the university’s Institute for Genomic Biology. “Screening for compounds that inhibit particular kinds of protein-DNA binding is a very important step in drug development.”

Developed by Brian Cunningham, a U. of I. professor of electrical and computer engineering, the photonic crystal biosensors consist of a low-refractive-index polymer grating coated with a film of high-refractive-index titanium oxide, attached to the bottom of a standard 384-well microplate. Each well functions as a tiny test tube with a biosensor in the bottom.

“First, we selectively attach a biomolecule, such as DNA, to the bottom of each well. Then we see how that biomolecule interacts with other molecules, including drugs,” said Cunningham, who also is affiliated with the university’s Beckman Institute, Micro and Nanotechnology Laboratory, and Institute for Genomic Biology.

By examining the light reflected from the photonic crystal, the researchers can tell when molecules are added to, or removed from, the crystal surface. The measurement technique can be used, for example, in a high-throughput screening mode to rapidly identify molecules and compounds that prevent DNA-protein binding.

The researchers demonstrated the new technology by examining two very different protein-DNA interactions. The first was the bacterial toxin-antitoxin system MazEF, which binds to DNA in a sequence-specific manner and is thought to be responsible for the maintenance of resistance-encoding plasmids in certain infectious bacteria. The second was the human apoptosis-inducing factor (AIF), a protein that binds to chromosomal DNA in a DNA-sequence-independent manner.

The photonic crystal biosensor technology was further utilized in a screen for inhibitors of the AIF-DNA interaction, and through this screen aurin tricarboxylic acid was identified as the first in vitro inhibitor of AIF.

“Aurin tricarboxylic acid displayed about 80 percent inhibition of AIF-DNA binding,” Hergenrother said. “Aurin tricarboxylic acid was the only compound to exhibit significant inhibition out of approximately 1,000 compounds screened.”

While the photonic crystal biosensor was demonstrated only for protein-DNA interactions, analogous experiments with protein-RNA interactions, and protein-protein interactions are also possible, Cunningham said. “We also could grow cancer cells on the photonic crystal surface, and see how different drugs affect cell growth.”

The researchers describe their work in the journal ACS Chemical Biology. With Cunningham and Hergenrother, the paper’s co-authors are graduate student and lead author Leo Chan, and graduate students Maria Pineda and James Heeres.

The work was funded by the National Institutes of Health.

Editor’s note: To reach Brian Cunningham, call 217-265-6291; bcunning@illinois.edu

James E. Kloeppel | University of Illinois
Further information:
http://www.illinois.edu

More articles from Physics and Astronomy:

nachricht Physics boosts artificial intelligence methods
19.10.2017 | California Institute of Technology

nachricht NASA team finds noxious ice cloud on saturn's moon titan
19.10.2017 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>