Featured Research

from universities, journals, and other organizations

Newly Found DNA Catalysts Cleave DNA With Water Molecule

Date:
August 25, 2009
Source:
University of Illinois at Urbana-Champaign
Summary:
Better tools for manipulating DNA in the laboratory may soon be possible with newly discovered deoxyribozymes (catalytic DNA) capable of cleaving single-stranded DNA, researchers say.

Better tools for manipulating DNA in the laboratory may soon be possible with newly discovered deoxyribozymes (catalytic DNA) capable of cleaving single-stranded DNA, say Scott Silverman and other researchers at the University of Illinois.
Credit: Photo by L. Brian Stauffer

Better tools for manipulating DNA in the laboratory may soon be possible with newly discovered deoxyribozymes (catalytic DNA) capable of cleaving single-stranded DNA, researchers at the University of Illinois say.

The deoxyribozymes accomplish the DNA cleavage with the sequence-selectivity and site-selectivity required for a practical catalyst, the researchers say.

"Our work suggests that deoxyribozymes have significant potential as sequence-specific DNA cleavage reagents," said chemistry professor Scott Silverman. "The hope is that we can take this fundamental advance and develop the ability to use DNA as a practical catalyst to cleave double-stranded DNA."

Silverman, postdoctoral research associate Madhavaiah Chandra and graduate student Amit Sachdeva report their discovery in a paper accepted for publication in Nature Chemical Biology.

The researchers discovered the new deoxyribozymes while searching for artificial sequences of DNA that could cleave proteins. The newly found catalysts function in a fashion similar to restriction enzymes, although to date by cleaving only single-stranded DNA.

Restriction enzymes, which allow scientists to cut and paste portions of double-stranded DNA, are the fundamental catalysts of molecular biology.

Each restriction enzyme, however, has a limited number of DNA sequences it can cut. Consequently, only a few percent of arbitrarily chosen DNA sequences can be cut by commercially available restriction enzymes.

Like natural restriction enzymes, the new catalysts are both sequence-specific and site-specific. "This means we can target a particular sequence, and we know we will cut at only one site within that sequence," Silverman said. "By appropriately picking the recognition and enzyme regions of the catalyst, we should be able to cut many more DNA sequences than is possible with current restriction enzymes."

The new DNA catalysts require two metal ions – manganese and zinc – to carry out their catalysis, "which is intriguing, because many natural protein-based nucleases (which cleave DNA) similarly require two metal ions," Silverman said. "One or both of the metals are presumably involved in the chemical mechanism by which our DNA catalyst achieves hydrolysis of the DNA backbone."

DNA hydrolysis is a very challenging chemical reaction, much more difficult to perform than the cleavage of a strand of RNA, Silverman said. In cleaving DNA, a water molecule must be brought in for the breaking reaction to occur. Also, both the DNA and the catalyst must be arranged appropriately in three-dimensional space.

How all of this happens with the DNA catalysts is not yet clear. Silverman's research group continues to probe the structure and mechanism of the catalysts, along with identifying and characterizing catalysts with different recognition sites.

"So far, we have achieved cleavage of single-stranded DNA targets," Silverman said. "The next big step is to cleave double-stranded DNA targets."

The National Institutes of Health, the Defense Threat Reduction Agency, and the David and Lucile Packard Foundation funded the work.


Story Source:

The above story is based on materials provided by University of Illinois at Urbana-Champaign. Note: Materials may be edited for content and length.


Cite This Page:

University of Illinois at Urbana-Champaign. "Newly Found DNA Catalysts Cleave DNA With Water Molecule." ScienceDaily. ScienceDaily, 25 August 2009. <www.sciencedaily.com/releases/2009/08/090816170925.htm>.
University of Illinois at Urbana-Champaign. (2009, August 25). Newly Found DNA Catalysts Cleave DNA With Water Molecule. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2009/08/090816170925.htm
University of Illinois at Urbana-Champaign. "Newly Found DNA Catalysts Cleave DNA With Water Molecule." ScienceDaily. www.sciencedaily.com/releases/2009/08/090816170925.htm (accessed September 17, 2014).

Share This



More Plants & Animals News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

AFP (Sep. 16, 2014) Since the arrival of Ebola in Ivory Coast, Ivorians have been abandoning their pets, particularly monkeys, in the fear that they may transmit the virus. Duration: 00:47 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