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.

"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 July 25, 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 July 25, 2014).

Share This




More Matter & Energy News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. Video provided by TheStreet
Powered by NewsLook.com
Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
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