Featured Research

from universities, journals, and other organizations

How nitrous oxide is decomposed: Researchers identify structure of enzyme that breaks down potent greenhouse gas

Date:
August 22, 2011
Source:
Karlsruhe Institute of Technology
Summary:
Nitrous oxide is a harmful climate gas. Its effect as a greenhouse gas is 300 times stronger than that of carbon dioxide. Nitrous oxide destroys the ozone layer. In industrial agriculture, it is generated on excessively fertilized fields when microorganisms decompose nitrate fertilizers. Decomposition of nitrous oxide frequently is incomplete and strongly depends on environmental conditions. Researchers have now identified the structure of the enzyme that decomposes nitrous oxide and the decomposition mechanism.

Nitrous oxide (N2O) is a harmful climate gas. Its effect as a greenhouse gas is 300 times stronger than that of carbon dioxide. Nitrous oxide destroys the ozone layer. In industrial agriculture, it is generated on excessively fertilized fields when microorganisms decompose nitrate fertilizers. Decomposition of nitrous oxide frequently is incomplete and strongly depends on environmental conditions. Researchers from Freiburg, Constance, and KIT have now identified the structure of the enzyme that decomposes nitrous oxide and the decomposition mechanism.

Their results are published in the journal Nature.

The study demonstrated that the N2O-reductase enzyme possesses active centers made up of four copper atoms and two sulfur atoms. "Surprisingly, we found that microbiologists all over the world have assumed an incorrect structure so far," explains Professor Oliver Einsle, group leader at the Institute of Organic Chemistry and Biochemistry of the University of Freiburg. Scientists have assumed a single sulfur atom only and have not been able to completely identify the nitrous oxide decomposition mechanism. Based on the new data, the reaction sequence of the enzyme can be modeled much better. Future investigations are to provide further details and help understand which influence environmental conditions have on the process.

"It was of decisive importance that all steps of our investigation were executed in the absence of air oxygen," emphasizes Walter G. Zumft, retired professor of Karlsruher Institute of Technology. In contact with oxygen, parts of the enzyme react and the enzyme changes its structure. Together with Dr. Anja Pomowski from the University of Freiburg, the bacteria were cultivated under an oxygen-free atmosphere, the enzymes were isolated on a large scale, crystallized, and the structure was analyzed using X-rays. The team of four authors was completed by Professor Peter Kroneck from the University of Constance.

"The current study provides interesting and complementary insight into the nitrogen cycle," says Dr. Ralf Kiese from the KIT Institute of Meteorology and Climate Research. Nitrous oxide and nitrogen production on fields, pastures, and in forests depends on a multitude of often opposing effects. Last year, a KIT study demonstrated that animal husbandry may lead to less nitrous oxide unter certain conditions (doi:10.1038/nature08931). Detailed knowledge of microbial processes and their dependence on environmental conditions might help to better model the nitrous oxide contribution to the climate. In the long term, it might even be feasible to use the knowledge in order to prevent nitrous oxide from being released into the atmosphere, for example, by additives in fertilizers that preserve the functioning of N2O-reductase or by optimized processes in sewage treatment plants.


Story Source:

The above story is based on materials provided by Karlsruhe Institute of Technology. Note: Materials may be edited for content and length.


Journal References:

  1. Anja Pomowski, Walter G. Zumft, Peter M. H. Kroneck, Oliver Einsle. N2O binding at a [4Cu:2S] copper–sulphur cluster in nitrous oxide reductase. Nature, 2011; DOI: 10.1038/nature10332
  2. Benjamin Wolf, Xunhua Zheng, Nicolas Brόggemann, Weiwei Chen, Michael Dannenmann, Xingguo Han, Mark A. Sutton, Honghui Wu, Zhisheng Yao, Klaus Butterbach-Bahl. Grazing-induced reduction of natural nitrous oxide release from continental steppe. Nature, 2010; 464 (7290): 881 DOI: 10.1038/nature08931

Cite This Page:

Karlsruhe Institute of Technology. "How nitrous oxide is decomposed: Researchers identify structure of enzyme that breaks down potent greenhouse gas." ScienceDaily. ScienceDaily, 22 August 2011. <www.sciencedaily.com/releases/2011/08/110822091605.htm>.
Karlsruhe Institute of Technology. (2011, August 22). How nitrous oxide is decomposed: Researchers identify structure of enzyme that breaks down potent greenhouse gas. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2011/08/110822091605.htm
Karlsruhe Institute of Technology. "How nitrous oxide is decomposed: Researchers identify structure of enzyme that breaks down potent greenhouse gas." ScienceDaily. www.sciencedaily.com/releases/2011/08/110822091605.htm (accessed April 17, 2014).

Share This



More Earth & Climate News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Great British Farmland Boom

The Great British Farmland Boom

Reuters - Business Video Online (Apr. 17, 2014) — Britain's troubled Co-operative Group is preparing to cash in on nearly 18,000 acres of farmland in one of the biggest UK land sales in decades. As Ivor Bennett reports, the market timing couldn't be better, with farmland prices soaring over 270 percent in the last 10 years. Video provided by Reuters
Powered by NewsLook.com
Small Reactors Could Be Future of Nuclear Energy

Small Reactors Could Be Future of Nuclear Energy

AP (Apr. 17, 2014) — After the Fukushima nuclear disaster, the industry fell under intense scrutiny. Now, small underground nuclear power plants are being considered as the possible future of the nuclear energy. (April 17) Video provided by AP
Powered by NewsLook.com
Change of Diet Helps Crocodile Business

Change of Diet Helps Crocodile Business

Reuters - Business Video Online (Apr. 16, 2014) — Crocodile farming has been a challenge in Zimbabwe in recent years do the economic collapse and the financial crisis. But as Ciara Sutton reports one of Europe's biggest suppliers of skins to the luxury market has come up with an unusual survival strategy - vegetarian food. Video provided by Reuters
Powered by NewsLook.com
How Mt. Everest Helped Scientists Research Diabetes

How Mt. Everest Helped Scientists Research Diabetes

Newsy (Apr. 15, 2014) — British researchers were able to use Mount Everest's low altitudes to study insulin resistance. They hope to find ways to treat diabetes. Video provided by Newsy
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:

More Coverage


Climate Change and Ozone Destruction Hastened With Nitrous Oxide Used in Agriculture

Aug. 15, 2011 — Researchers have discovered a new binding site for nitrous oxide (N2O). Nitrous oxide reductase, an enzyme containing copper, plays a key role in the biochemical process by ... read more
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