Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Nanotechnology: Probing for interactions: Nanoparticles offer insights into interactions between single-stranded DNA and their binding proteins

Schematic illustration showing the mechanism used to probe interactions between single-stranded DNA (ssDNA) and single stranded DNA-binding protein (SSB)
Copyright : 2011 ACS
Schematic illustration showing the mechanism used to probe interactions between single-stranded DNA (ssDNA) and single stranded DNA-binding protein (SSB)

Copyright : 2011 ACS

Abstract:
Double-stranded DNA must disentangle itself into single strands during replication or repair to allow functional molecules to bind and perform their various operations. Cellular proteins specifically bind to single-stranded DNA to prevent their premature recombination. Unfortunately, detailed studies of these DNA-protein interactions have been hindered by the need for expensive instrumentation and time-consuming labelling techniques. Yen Nee Tan at the A*STAR Institute of Materials Research and Engineering and co-workers1 have now developed a convenient method to characterize the interactions between single-stranded DNA and their binding proteins.

Nanotechnology: Probing for interactions: Nanoparticles offer insights into interactions between single-stranded DNA and their binding proteins

Singapore | Posted on November 28th, 2011

The researchers used the optical properties of gold nanoparticles to probe the mechanism of protein-DNA binding. When the nanoparticles were well dispersed in solution, they yielded a bright red color, but when aggregated, the solution changed to blue. Tan and co-workers discovered that when single-stranded DNA and its binding protein were both present in the solution, coupled with a salt that stimulates nanoparticle aggregation, the DNA remained red in color, indicating that the DNA-protein complexes had bound with the nanoparticles through electrosteric stabilization forces. In contrast, when the protein or single-stranded DNA was introduced alone in the salt solution, there was a greater shift to the blue-grey color, indicating nanoparticle aggregation (see image).

"The greatest challenge in this work was to determine the optimum conditions for single-stranded DNA to bind with its binding protein to form complexes that confer the highest stability to gold nanoparticles from salt-induced aggregation," says Tan.

The researchers attribute binding of the nanoparticles and the DNA-protein complexes to the presence of sulphur-containing groups in the protein, which are known to create strong bonds with gold. The protein molecules alone are smaller in molecular size than the protein-DNA complexes, leading to a less effective steric stabilization of the nanoparticles.

Tan and co-workers showed that there was a minimum length of DNA sequence under which the binding protein-DNA adhesion mechanism could operate. They found that the binding protein had a preference for binding to specific chemical units (bases) which make up DNA, and were able to spot DNA sequence variations, called single nucleotide polymorphisms (SNPs), even at the extreme ends of the molecule which are difficult to identify. Double-stranded DNA with SNPs cannot bind together so closely. The binding protein can thus attach to the dissociated single-stranded DNA to form protein-DNA complexes, offering sites to which gold nanoparticles can adhere.

"We plan to further develop this assay into a hassle-free genotyping assay to detect SNPs in real biological samples containing long genomic DNA," says Tan.

The A*STAR-affiliated researchers contributing to this research are from the Institute of Materials Research and Engineering

####

For more information, please click here

Contacts:
Lee Swee Heng

Copyright © The Agency for Science, Technology and Research (A*STAR)

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 Links

Institute of Materials Research and Engineering:

Research article in Analytical Chemistry

Related News Press

News and information

New solar power material converts 90 percent of captured light into heat: SunShot Project aims to make solar cost competitive October 29th, 2014

Tiny carbon nanotube pores make big impact October 29th, 2014

Microrockets fueled by water neutralize chemical and biological warfare agents October 29th, 2014

Nanosafety research – there’s room for improvement October 29th, 2014

Chemistry

A new cheap and efficient method to improve SERS, an ultra-sensitive chemical detection technique October 28th, 2014

Iranian, Malaysian Scientists Study Nanophotocatalysts for Water Purification October 23rd, 2014

Could I squeeze by you? Ames Laboratory scientists model molecular movement within narrow channels of mesoporous nanoparticles October 21st, 2014

Non-Toxic Nanocatalysts Open New Window for Significant Decrease in Reaction Process October 19th, 2014

Nanomedicine

'Electronic skin' could improve early breast cancer detection October 29th, 2014

Tiny carbon nanotube pores make big impact October 29th, 2014

Molecular beacons shine light on how cells 'crawl' October 27th, 2014

New nanodevice to improve cancer treatment monitoring October 27th, 2014

Discoveries

New solar power material converts 90 percent of captured light into heat: SunShot Project aims to make solar cost competitive October 29th, 2014

Tiny carbon nanotube pores make big impact October 29th, 2014

Microrockets fueled by water neutralize chemical and biological warfare agents October 29th, 2014

Nanoparticles Display Ability to Improve Efficiency of Filters October 28th, 2014

Announcements

New solar power material converts 90 percent of captured light into heat: SunShot Project aims to make solar cost competitive October 29th, 2014

Tiny carbon nanotube pores make big impact October 29th, 2014

Microrockets fueled by water neutralize chemical and biological warfare agents October 29th, 2014

Nanosafety research – there’s room for improvement October 29th, 2014

Nanobiotechnology

Tiny carbon nanotube pores make big impact October 29th, 2014

Molecular beacons shine light on how cells 'crawl' October 27th, 2014

Breakthrough in molecular electronics paves the way for DNA-based computer circuits in the future: DNA-based programmable circuits could be more sophisticated, cheaper and simpler to make October 27th, 2014

NYU Researchers Break Nano Barrier to Engineer the First Protein Microfiber October 23rd, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE