Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rensselaer Scientists Unlock Some Key Secrets of Photosynthesis

03.07.2012
Research on the Water Oxidation Reaction in Plants and Bacteria Helps Solve an Important Piece of the Solar Energy Conversion Puzzle; Represents a Major Step Toward a New Generation of Photovoltaics
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.”

The article published in the Royal Society of Chemistry journal Energy & Environmental Science can be found at: http://pubs.rsc.org/en/content/articlelanding/2012/ee/c2ee21210b

The Baruch ’60 Center for Biochemical Solar Energy Research is an integrated research and education program at Rensselaer that was inaugurated in October 2008 under the auspices of President Shirley Ann Jackson and Thomas R. Baruch ’60, a member of the Rensselaer Board of Trustees. Researchers at the center are working to develop the next generation of solar technology by studying one of the most powerful energy-converting machines in world — plants. Researchers use sophisticated new technologies and techniques that are being developed at the Baruch ’60 Center to understand the energy-converting power of plants and develop new technologies that mimic this extremely efficient natural system.

Published July 2, 2012
Contact: Mary L. Martialay
Phone: (518) 276-2146
E-mail: martim12@rpi.edu

Mary Martialay | EurekAlert!
Further information:
http://www.rpi.edu

More articles from Life Sciences:

nachricht Researchers target protein that protects bacteria's DNA 'recipes'
21.08.2018 | University of Rochester

nachricht Protein interaction helps Yersinia cause disease
21.08.2018 | Schwedischer Forschungsrat - The Swedish Research Council

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: It’s All in the Mix: Jülich Researchers are Developing Fast-Charging Solid-State Batteries

There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.

The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Air pollution leads to cardiovascular diseases

21.08.2018 | Ecology, The Environment and Conservation

Researchers target protein that protects bacteria's DNA 'recipes'

21.08.2018 | Life Sciences

A paper battery powered by bacteria

21.08.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>