Jeremy Craig, 404-413-1357
ATLANTA — A Georgia State University scientist has found a new way to simulate data in examining processes during photosynthesis, a method which will lead to a better understanding of how plants work.
Gary Hastings, professor of physics, has developed a way to better interpret measurements that investigate the molecular interactions involved in photosynthesis. By using the data provided through Hastings’ method, scientists will be able to more accurately develop a mathematical model of photosynthetic processes in plants.
The research appears in a journal article released Monday in the Proceedings of the National Academy of Sciences.
In photosynthesis, plants capture sunlight and use it to produce carbohydrates used as energy. In the process sunlight is used to transfer electrons across a membrane, Hastings explained. There is a positive terminal on one side of the membrane and a negative terminal on the other.
“Essentially, a plant is a solar-powered battery,” he said. “The process is remarkably efficient, much more so than in artificial materials. The question is: ‘How do electrons get across this membrane with such efficiency?’”
Plants contain pigment molecules, such as chlorophyll and quinone, which give them their colors. In the process of photosynthesis, electrons “hop” from one pigment to the next to get across the membrane. Proteins interact with these pigments, and this gives them special properties allowing them to move electrons quickly and efficiently across the membrane.
“The burning question is, what is it about these protein interactions that modify the properties of the pigments to help get electrons across the membrane? This is really a structural biology question, and everything we do is geared towards understanding how proteins modify these pigment properties,” Hastings said.
The new method Hastings shows in his article provides an approach using numerical, or quantitative, data to describe the results of research using a process called Fourier Transform Infrared (FTIR) spectroscopy. Previously, the norm for the field was to use a more descriptive, or qualitative, approach.
This research, in time, may lead to ways to predict how new plant strains might function more efficiently – something with implications in many fields, including biofuel research.
Hastings’ research was made possible by powerful supercomputing resources at GSU. Hastings and his team used the university’s IBM p5 supercomputer, called URSA, which allowed for the efficient processing of huge calculations in days, instead of the months it would have taken on even the fastest desktop computers.
GSU recently increased its supercomputing power by acquiring an IBM p7-755 supercomputer, named CARINA. It can run calculations at more than 14 trillion calculations per second.
Hastings’ article, “Calculated Vibrational Properties of Pigments in Protein Binding Sites,” appears online in the Proceedings of the National Academy of Sciences, located online at www.pnas.org.
May 17, 2001