Featured Research

from universities, journals, and other organizations

Fake Photosynthesis? Test-Tube System In Science Paper Sheds Light On The Oxygen We Breathe, UD Prof Says

Date:
March 8, 1999
Source:
University Of Delaware
Summary:
A test-tube photosynthesis system--described in the March 5 issue of Science--mimics a metal cluster that helps green plants harness sunlight to turn water into oxygen, says University of Delaware chemist Arnold L. Rheingold, a coauthor of the journal article, who analyzed the Yale University invention.

A test-tube photosynthesis system--described in the March 5 issue of Science--mimics a metal cluster that helps green plants harness sunlight to turn water into oxygen, says University of Delaware chemist Arnold L. Rheingold, a coauthor of the journal article, who analyzed the Yale University invention.

Related Articles


"We owe our lives to oxygen, and virtually all of the oxygen we breathe is produced by plants and some bacteria, through photosynthesis," says Rheingold, one of the world's 10 most frequently cited chemists. "Yet, our understanding of photosynthesis has been limited by its complexity. This relatively simple, artificial system should shed light on how life-giving oxygen is produced on Earth, which points to our origins and how the atmosphere evolved on our planet."

A UD professor of chemistry and biochemistry, Rheingold doesn't foresee any immediate practical uses for fake photosynthesis. In industrial settings, oxygen can already be mass-produced by fractionating liquid air, he notes. But, he adds, "Next-generation solar power will require more efficient water-splitting techniques," so the artificial photosynthesis system may suggest new strategies for converting sunlight into electricity. And, he says, such fundamental knowledge enhances our appreciation of the natural world.

Rheingold teamed up with UD graduate student Louise M. Liable-Sands to precisely map the molecular structure of the test-tube photosynthesis system, developed by Yale graduate student Julian Limburg, lead author of the Science article, with graduate student John S. Vrettos and Profs. Robert H. Crabtree and Gary W. Brudvig.

"I doubt there's a commercial need for the Yale oxygen-making factory," Rheingold says. "But, it may allow us to understand how our planet came to have oxygen. The early environment on Earth was quite inhospitable. The evolution of photosynthetic plants created oxygen and completely changed the atmosphere on our planet. That's an amazing process. Now, we can more fully explore it!"

Mimicking Nature's magic tricks

To change water into one of its constituent elements, dioxygen (O2), the Yale research team needed a catalyst to trigger the reaction. Their solution was a metal-based, "dioxygen-evolving complex (OEC)"--essentially, a metal cluster of two manganese atoms activated by bleach-which serves as the basis of the Photosystem II (PSII).

The synthetic, metal cluster is patterned after a naturally occurring, four-manganese cluster involved in plant functions, says Rheingold, who describes his X-Ray Crystallography Laboratory as "the Supreme Court of chemistry," where researchers worldwide send samples to be deciphered.

The natural protein is highly complex, Rheingold says, and "it would be hard to use a leaf to make oxygen in the lab." So, the Yale scientists painstakingly developed a simpler, synthetic version, which Rheingold describes as "an individual work of art."

When they identified a synthetic complex that seemed to turn water into oxygen, the Yale scientists sent their crystals to Rheingold, who determined the extent to which they resembled their natural cousins. In Rheingold's lab, a single crystal, when bombarded by a beam of X-rays, produced a pattern of scattered beams related to the arrangement of atoms in the molecules in the crystal. Using a computer, the UD researchers could then position the atoms to create a color-coded "map" of the molecular architecture of the Yale sample, Rheingold explains.

To understand X-ray crystallography, he says, "Think of a mirrored disco ball, hanging over a dance floor, reflecting spots of light onto the surrounding walls." Mapping the spots reveals the shape of the disco ball. Similarly, diffracted X-rays can be analyzed to determine a material's structure.

In the case of the metal cluster in the Yale photosynthesis system, he says, "It was a bit of a miracle that we were able to determine the structure because of the inherent weakness of the reflections of this crystal. The structure was solved largely because of the persistence of my graduate student."

###

UD web site - http://www.udel.edu/arcade/arnrhein.htm

Yale web site - http://www.chem.yale.edu/~brudvig/


Story Source:

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


Cite This Page:

University Of Delaware. "Fake Photosynthesis? Test-Tube System In Science Paper Sheds Light On The Oxygen We Breathe, UD Prof Says." ScienceDaily. ScienceDaily, 8 March 1999. <www.sciencedaily.com/releases/1999/03/990308055632.htm>.
University Of Delaware. (1999, March 8). Fake Photosynthesis? Test-Tube System In Science Paper Sheds Light On The Oxygen We Breathe, UD Prof Says. ScienceDaily. Retrieved November 23, 2014 from www.sciencedaily.com/releases/1999/03/990308055632.htm
University Of Delaware. "Fake Photosynthesis? Test-Tube System In Science Paper Sheds Light On The Oxygen We Breathe, UD Prof Says." ScienceDaily. www.sciencedaily.com/releases/1999/03/990308055632.htm (accessed November 23, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Sunday, November 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

AFP (Nov. 21, 2014) Toyota presented its hydrogen fuel-cell compact car called "Mirai" to US consumers at the Los Angeles auto show. The car should go on sale in 2015 for around $60.000. It combines stored hydrogen with oxygen to generate its own power. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
Google Announces Improvements To Balloon-Borne Wi-Fi Project

Google Announces Improvements To Balloon-Borne Wi-Fi Project

Newsy (Nov. 21, 2014) In a blog post, Google said its balloons have traveled 3 million kilometers since the start of Project Loon. Video provided by Newsy
Powered by NewsLook.com
Raw: Paralyzed Marine Walks With Robotic Braces

Raw: Paralyzed Marine Walks With Robotic Braces

AP (Nov. 21, 2014) Marine Corps officials say a special operations officer left paralyzed by a sniper's bullet in Afghanistan walked using robotic leg braces in a ceremony to award him a Bronze Star. (Nov. 21) Video provided by AP
Powered by NewsLook.com
British 'Bio-Bus' Is Powered By Human Waste

British 'Bio-Bus' Is Powered By Human Waste

Buzz60 (Nov. 21, 2014) British company GENeco debuted what its calling the Bio-Bus, a bus fueled entirely by biomethane gas produced from food scraps and sewage. Jen Markham explains. Video provided by Buzz60
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:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

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