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:4/15/2016)... , April 15, 2016  A new partnership ... more accurate underwriting decisions in a fraction of ... competitively priced and high-value life insurance policies to ... With Force Diagnostics, rapid testing (A1C, ... data readings (blood pressure, weight, pulse, BMI, and ...
(Date:4/13/2016)... CHICAGO , April 13, 2016  IMPOWER physicians ... are setting a new clinical standard in telehealth ... By leveraging the higi platform, IMPOWER patients can ... weight, pulse and body mass index, and, when they ... quick and convenient visit to a local retail location ...
(Date:3/29/2016)... , March 29, 2016 ... "Company") LegacyXChange "LEGX" and SelectaDNA/CSI Protect are pleased to ... ink used in a variety of writing instruments, ensuring ... of originally created collectibles from athletes on LegacyXChange will ... analysis of the DNA. Bill Bollander ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... ... June 24, 2016 , ... Researchers at the Universita ... miRNAs in people with peritoneal or pleural mesothelioma. Their findings are the subject of ... now. , Diagnostic biomarkers are signposts in the blood, lung fluid or tissue ...
(Date:6/23/2016)... 23, 2016   Boston Biomedical , an ... designed to target cancer stemness pathways, announced that ... Orphan Drug Designation from the U.S. Food and ... cancer, including gastroesophageal junction (GEJ) cancer. Napabucasin is ... inhibit cancer stemness pathways by targeting STAT3, and ...
(Date:6/23/2016)... 23, 2016 Houston Methodist Willowbrook Hospital ... Sports Association to serve as their official health ... Methodist Willowbrook will provide sponsorship support, athletic training ... association coaches, volunteers, athletes and families. ... Sports Association and to bring Houston Methodist quality ...
(Date:6/23/2016)... -- The Biodesign Challenge (BDC), a university competition that asks ... systems and biotechnology, announced its winning teams at the ... York City . The teams, chosen ... MoMA,s Celeste Bartos Theater during the daylong summit. Keynote ... of architecture and design, and Suzanne Lee , ...
Breaking Biology Technology: