Featured Research

from universities, journals, and other organizations

Photosynthesis mechanism: Tofu-like crystalline catalysts for producing clean energy

Date:
September 18, 2013
Source:
Okayama University
Summary:
New research demystifies the reaction mechanisms of photosynthesis. The findings may lead to the development of methods for producing an unlimited source of clean energy.

The catalytic core for photosynthetic water-splitting.
Credit: Image courtesy of Okayama University

Research by Professor Jian-Ren Shen at Okayama University demystifies the reaction mechanisms of photosynthesis and the findings may lead to the development of methods for producing an unlimited source of clean energy.

Professor Jian-Ren Shen is recognized for his pioneering research on clarifying the fundamental reaction mechanism that governs photosynthetic water splitting, a process with fundamental importance in understanding how oxygenic photosynthetic organisms, such as plants, use energy from sunlight, water, and CO2 to survive.

"I first started research on photosynthetic proteins in the beginning of my doctorate project," says Shen. "Our findings published in 2011 were based on x-ray diffraction experiments of large, high quality single crystal of so-called 'photosystem II' (PS II) at Japan's SPring-8 synchrotron radiation facility at Harima. The ability to produce large sized, single crystals of PS II, an extremely large membrane-protein complex, was critical for determining the crystalline structure of this protein complex to a resolution of 1.9 Angstroms. These results are the culmination of 20 years of my life spent on the development and improvement of the process to produce such large crystals."

Professor Shen's initial research on photosynthesis was focused on clarifying the effects of air pollution on plants. The objectives of this research necessitated clarification of the fundamental mechanism underlying photosynthesis, which in turn required the production of a high quality crystal of PS II. "After many years of exhaustive experiments and uncountable failures, we eventually succeeded in producing large, 'tofu-like' single crystals of PS II with dimensions of 0.7 x 0.4 x 0.1 mm," explains Shen. "This was a major breakthrough that led to the ultra-high resolution analysis of PS II."

Recent reports on the crystallographic analysis of PS II can be traced back to the early 2000s but the results yielded only 'fuzzy' images because of imperfections in the samples. In contrast the 2011 findings by Shen and colleagues yielded unprecedented images of the core of the PS II protein, showing the existence of cubic-core of four manganese atoms, five oxygen atoms, and a calcium atom, which constitutes the heart of plant life (Science 2011, 334, 1630).

"This cubic structure of Mn4CaO5 acts as a catalyst for the water splitting reaction induced by sunlight," explains Shen. "These results have many important practical applications including the possibility of synthesizing artificial catalyst to dissociate water into oxygen and hydrogen to produce electricity in fuel cells, for example."

Indeed there is increasing interests in 'artificial photosynthesis' for the production of energy. But Professor Shen says that his group will focus on basic research on the reaction mechanism of PS II. "Our next goal is to clarify the so-called 'intermediate structure' of PS II," says Shen. "To do so we require even higher resolution x-ray diffraction experiments at both space and time levels. We are planning to use the SACLA X-ray Free Electron Laser (XFEL) facility in SPring-8 to achieve this. This will enable us to look at the movement of atoms during photosynthesis."


Story Source:

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


Journal Reference:

  1. Yasufumi Umena, Keisuke Kawakami, Jian-Ren Shen, Nobuo Kamiya. Crystal structure of oxygen-evolving photosystem II at a resolution of 1.9 . Nature, 2011; 473 (7345): 55 DOI: 10.1038/nature09913

Cite This Page:

Okayama University. "Photosynthesis mechanism: Tofu-like crystalline catalysts for producing clean energy." ScienceDaily. ScienceDaily, 18 September 2013. <www.sciencedaily.com/releases/2013/09/130918130207.htm>.
Okayama University. (2013, September 18). Photosynthesis mechanism: Tofu-like crystalline catalysts for producing clean energy. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2013/09/130918130207.htm
Okayama University. "Photosynthesis mechanism: Tofu-like crystalline catalysts for producing clean energy." ScienceDaily. www.sciencedaily.com/releases/2013/09/130918130207.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

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
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Car Market on the Rebound?

Europe's Car Market on the Rebound?

Reuters - Business Video Online (July 23, 2014) Daimler kicks off a round of second-quarter earnings results from Europe's top carmakers with a healthy set of numbers - prompting hopes that stronger sales in Europe will counter weakness in emerging markets. Hayley Platt reports. Video provided by Reuters
Powered by NewsLook.com
9/11 Commission Members Warn of Terror "fatigue" Among American Public

9/11 Commission Members Warn of Terror "fatigue" Among American Public

Reuters - US Online Video (July 22, 2014) Ten years after releasing its initial report, members of the 9/11 Commission warn of the "waning sense of urgency" in combating terrorists attacks. Mana Rabiee reports. Video provided by Reuters
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