Navigation Links
Rensselaer scientists unlock some key secrets of photosynthesis
Date:7/2/2012

Troy, N.Y. New research led by chemists in the Baruch '60 Center for Biochemical Solar Energy Research at Rensselaer Polytechnic Institute is seeking to detail the individual steps of highly efficient reactions that convert sunlight into chemical energy within plants and bacteria.

In a paper published in the recent edition [DOI:10.1039/C2EE21210B] of the Royal Society of Chemistry journal, Energy & Environmental Science, the scientists led by K. V. Lakshmi, Rensselaer assistant professor of chemistry and chemical biology and scientific lead at the Baruch '60 Center have provided important information on a specific portion of the photosynthetic process called photosystem II. It has been a major challenge to directly observe the individual steps of the solar water-splitting reaction that takes place in photosystem II, Lakshmi said. This finding provides new foundational research into how plants efficiently convert energy from the sun and could help inform the development of a new, highly robust, and more efficient generation of solar-energy technologies.

Lakshmi was joined in the research by Rensselaer students Sergey Milikisyants, Ruchira Chatterjee, and Christopher Coates, as well as Faisal H.M. Koua and Professor Jian-Ren Shen of Okayama University in Japan. The research is funded by the Office of Basic Energy Sciences, U.S. Department of Energy.

"The photosynthetic system of plants is nature's most elaborate nanoscale biological machine," said Lakshmi. "It converts light energy at unrivaled efficiency of more than 95 percent compared to 10 to 15 percent in the current man-made solar technologies. In order to capture that efficiency in solar energy technology, we must first tackle the basic science of photosynthesis by understanding the chemistry behind its ultra-efficient energy conversion process in nature."

The new research focuses on the first of two photochemical reactions that plants use to convert solar energy into chemical energy that takes place within photosystem II. Specifically, the researchers studied the binding and activation of the substrate water molecules in the catalytic site of photosystem II. Photosystem II is a protein complex in plants and cyanobacteria that uses photons of light to split water molecules. This is known as the solar oxidation of water. The protons and electrons resulting from this split are then used by the plant to fuel the remaining systems in the photosynthetic process that transforms light into chemical energy.

"Photosystem II is the engine of life," Lakshmi said. "It performs one of the most energetically demanding reactions known to mankind, splitting water, with remarkable ease and efficiency."

One of the difficulties in studying photosystem II is that conventional methods have not yet been able to deeply probe the photosystem II complex, according to Lakshmi, and the mechanism of the photochemical reactions must be fully understood before bio-inspired technologies that mimic the natural processes of photosynthesis can effectively be developed.

In the new research, the scientists investigated the catalytic site of photosystem II, referred to as the oxygen-evolving complex. This is part of the system that breaks down the water. It does so in five distinct stages. Only the first two of these stages have been investigated in any detail, according to Lakshmi, because the remaining stages are relatively unstable and quickly change.

To understand the more unstable stages of the process, scientists need advanced scientific tools that can probe these complex systems at the atomic level. For this research, Lakshmi and her colleagues trapped three different species of photosystem II in one of the more unstable stages of the process the third stage in the oxygen-evolving complex called photochemical S2 intermediate by using low-temperature illumination of photosystem II. They then analyzed the system using an advanced spectroscopic technique called two-dimensional hyperfine sub-level correlation spectroscopy.

The tool detects the weak magnetic interactions in the catalytic site to uncover the structure and activation of the substrate water molecules in the S2 intermediate of photosystem II. The technology, found in few labs in the world, according to Lakshmi, identified four important groups of hydrogen atoms arising from substrate water molecules within the oxygen-evolving complex. This is a significant step in determining the fate of the water molecules in the solar water oxidation reaction that occurs within photosystem II, Lakshmi said.

"Water is a very stable molecule and it takes four photons of light to split water," she said. "This is a challenge for chemists and physicists around the world as the four-photon reaction has very stringent requirements."


'/>"/>

Contact: Mary Martialay
martim12@rpi.edu
518-276-2146
Rensselaer Polytechnic Institute
Source:Eurekalert

Related biology news :

1. Scripps Research Institute Scientists Develop Alternative to Gene Therapy
2. Scientists urge new approaches to plant research
3. Scientists warn Brazils environmental leadership at risk
4. UCSB scientists compile first study of potential for tsunamis in northwestern California
5. Disappearing grasslands: ASU scientists to study dramatic environmental change
6. SFU scientists engage Science in fisheries debate
7. Hulk smash? Maybe not anymore: scientists block excess aggression in mice
8. UCLA scientists discover how key enzyme involved in aging, cancer assembles
9. Scientists reconstruct pre-Columbian human effects on the Amazon Basin
10. Scientists tie DNA repair to key cell signaling network
11. Top young Latin-American scientists named Pew Biomedical Fellows
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/6/2017)... 2017 RAM Group , Singaporean ... breakthrough in biometric authentication based on a ... to perform biometric authentication. These new sensors are based ... by Ram Group and its partners. This sensor will ... chains and security. Ram Group is a next ...
(Date:4/13/2017)... UBM,s Advanced Design and Manufacturing event in ... and evolving technology through its 3D Printing and Smart ... the expo portion of the event and feature a ... on trending topics within 3D printing and smart manufacturing. ... will take place June 13-15, 2017 at the Jacob K. ...
(Date:4/11/2017)... 2017 NXT-ID, Inc. (NASDAQ:   NXTD ... the appointment of independent Directors Mr. Robin D. Richards ... of Directors, furthering the company,s corporate governance and expertise. ... Gino Pereira , Chief ... to their guidance and benefiting from their considerable expertise as ...
Breaking Biology News(10 mins):
(Date:8/21/2017)... ... August 20, 2017 , ... Brian ... (JBO) starting 1 January 2018. The journal is published by SPIE, the international ... on the use of modern optical technology for improved health care and biomedical ...
(Date:8/21/2017)... Boston, MA (PRWEB) , ... August 21, 2017 ... ... healthcare consulting firm is utilizing its extensive experience with Health Economics and Outcomes ... on Electronic Health Record data. In 2014, US healthcare spending exceeded $3.0 trillion ...
(Date:8/18/2017)... (PRWEB) , ... August 18, 2017 , ... ... Lithography Equipment for the Semiconductor, MEMS, and Microfluidics Industries, announces the new Model ... specifications found more often in automated production mask aligners. OAI has already received ...
(Date:8/16/2017)... ... August 16, 2017 , ... ... and Electrospraying line of nanofiber and nanoparticle fabrication instruments ... the lab to fully automated pilot plants and equipment for industrial manufacturing. ...
Breaking Biology Technology: