Featured Research

from universities, journals, and other organizations

Scientists Reinvent DNA As Template To Produce Organic Molecules

Date:
August 23, 2004
Source:
Harvard University
Summary:
By piggybacking small organic molecules onto short strands of DNA, chemists at Harvard University have developed an innovative new method of using DNA as a blueprint not for proteins but for collections of complex synthetic molecules.

CAMBRIDGE, Mass. -- By piggybacking small organic molecules onto short strands of DNA, chemists at Harvard University have developed an innovative new method of using DNA as a blueprint not for proteins but for collections of complex synthetic molecules. The researchers will report on the prolific technique, dubbed "DNA-templated library synthesis," this week on the web site of the journal Science.

"The basic structures of proteins and nucleic acids seem limited when compared with the structures that can be created using modern synthetic chemistry, and yet this very modest set of protein and nucleic acid building blocks has given rise to the incredible complexity and diversity of living systems," says David R. Liu, associate professor of chemistry and chemical biology at Harvard. "We're interested in marrying fundamental features of biomolecules with synthetic organic chemistry in order to apply techniques such as translation, selection, and amplification to molecules beyond those found in cells and organisms."

Liu and his colleagues attached organic molecules to single DNA strands, each containing 10 DNA bases (A, C, G, or T). When two DNA strands with complementary sequences (A matches T, G matches C) spontaneously bond together, their associated organic molecules undergo a chemical reaction to generate a product. As a result, the DNA strands essentially serve as a miniature, sequence-programmable assembly line for products of chemical synthesis.

Because the resulting synthetic compounds are linked to DNA, techniques long used to screen and amplify the genetic mainstay can now be applied. Molecules can be "selected" for desired functional properties, and the survivors of these selections can then be copied using the polymerase chain reaction (PCR).

The application of DNA-templated synthesis has enabled a collection of DNA strands to be transformed into a corresponding collection of sequence-programmed small macrocyclic molecules with potentially interesting chemical and biological properties. A single member of the collection survived a selection on the basis of its ability to bind to a protein target, and the DNA encoding the survivor was amplified by PCR and sequenced to reveal its identity.

Liu's team found that small molecules bound to DNA can react to form larger products even when the DNA bases used to zip together the small molecules are far apart on a DNA template. This means that a template strand of 30 DNA bases, complementary to Liu's DNA codes for three different organic molecules, can encode three separate chemical reactions, leading to the multistep DNA-programmed synthesis of relatively complex cyclic products.

Chemical synthesis occurs very differently in laboratories and in cells. Chemists typically work with molecules that react to form products when they randomly collide at high concentrations. By contrast, biomolecules are found within cells at concentrations that are often a million times lower than the concentrations of molecules in laboratory reactors. In nature, the reactions between these highly dilute molecules are directed by enzymes that selectively bring certain biological reactants together. Liu and his colleagues are now using DNA as a similar type of intermediary to bring together synthetic small molecules that are otherwise too dilute to react, allowing minute quantities of sparse molecules to behave as denser mixtures when assembled together by DNA base pairing.

"We recognized that in order to apply such an approach to as many synthetic molecules as possible, we'd have to use a different type of template than an enzyme," Liu says. "The natural and robust zipping up of complementary DNA strands is a simple way to bring molecules at low concentrations together without having to develop an entirely new class of enzymes for each different type of molecule."

The 10-base DNA strands used by Liu's team are large enough to be stable at room temperature and in theory can encode thousands of individual small organic molecules.

Liu's co-authors are Zev J. Gartner, Brian N. Tse, Rozalina Grubina, Jeffrey B. Doyon, and Thomas M. Snyder, all of Harvard's Department of Chemistry and Chemical Biology. Their work was funded by the National Institute of General Medical Sciences at the National Institutes of Health, the Office of Naval Research, the Arnold and Mabel Beckman Foundation, the Searle Scholars Foundation, the Alfred P. Sloan Foundation, and fellowships from Bristol-Myers Squibb and the National Science Foundation.


Story Source:

The above story is based on materials provided by Harvard University. Note: Materials may be edited for content and length.


Cite This Page:

Harvard University. "Scientists Reinvent DNA As Template To Produce Organic Molecules." ScienceDaily. ScienceDaily, 23 August 2004. <www.sciencedaily.com/releases/2004/08/040820083639.htm>.
Harvard University. (2004, August 23). Scientists Reinvent DNA As Template To Produce Organic Molecules. ScienceDaily. Retrieved April 25, 2014 from www.sciencedaily.com/releases/2004/08/040820083639.htm
Harvard University. "Scientists Reinvent DNA As Template To Produce Organic Molecules." ScienceDaily. www.sciencedaily.com/releases/2004/08/040820083639.htm (accessed April 25, 2014).

Share This



More Matter & Energy News

Friday, April 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Next Stop America for France's TGV?

Next Stop America for France's TGV?

Reuters - Business Video Online (Apr. 24, 2014) General Electric keeps quiet on reports it's in talks to buy French turbine and train maker Alstom. Ivor Bennett reports on what could be an embarrassing rumour for the French government, with business-friendly reforms proving a hard sell. Video provided by Reuters
Powered by NewsLook.com
Raw: Obama Plays Soccer With Japanese Robot

Raw: Obama Plays Soccer With Japanese Robot

AP (Apr. 24, 2014) President Obama briefly played soccer with a robot during his visit to Japan on Thursday. The President has been emphasizing technology along with security concerns during his visit. (April 24) Video provided by AP
Powered by NewsLook.com
Obama Encourages Japanese Student-Scientists

Obama Encourages Japanese Student-Scientists

AP (Apr. 24, 2014) President Obama spoke with student innovators in Japan and urged them to take part in increased opportunities for student exchanges with the US. (April 24) Video provided by AP
Powered by NewsLook.com
UN Joint Mission Starts Removing Landmines in Cyprus

UN Joint Mission Starts Removing Landmines in Cyprus

AFP (Apr. 23, 2014) The UN mission in Cyprus (UNFICYP) led a mine clearance demonstration on Wednesday in the UN-controlled buffer zone where demining operations are being conducted near the Cypriot village of Mammari. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins