A chance to explore the hottest research topic in St. Louis

A public outreach session introduces current research in photosynthesis through short talks, videos and demonstrations

By Diana Lutz

St. Louis is known for its plant science, but few of us know what is going on in the labs we drive by on the way to work. Now is our chance to find out.

The International Society of Photosynthesis Research, meeting this August in St. Louis, is offering an afternoon of talks and demonstrations about the original “green” chemistry invented by bacteria and plants and its relevance to our energy future.

Intended for teachers, students and the public, “Photosynthesis in Our Lives” will take place from 3-5 p.m. Aug. 11 in the Park View room at the Hyatt Regency St. Louis at The Arch.

Learn about the latest research, see algae balls turn water purple and watch leaves mysteriously float and sink. The event is free, but reservations are encouraged. RSVP to: http://parc.wustl.edu/outreachRSVP by Aug. 7.

What are scientists working on and why?
Robert Blankenship, PhD, the Lucille P. Markey Distinguished Professor of Arts & Sciences at Washington University in St. Louis and moderator of “Photosynthesis in Our Lives,” said he handpicked three internationally renowned scientists who are particularly engaging speakers to deliver 15-minute talks about photosynthesis and its relevance to the global energy crisis.

First up is Richard Cogdell of the University of Glasgow in the United Kingdom, who will speak about how plants (and some bacteria) grab the energy in sunlight. By way of introduction, here is Cogdell being interviewed for MicrobeWorld, the Youtube channel of the American Society for Microbiology.

Richard Cogdell explains why he finds photosynthesis interesting. The complete interview can be found at MicrobeWorld: http://www.youtube.com/watch?v=eLW0RWxAH60. Used with permission.

Next up is Gary Brudvig of Yale University, who will explain how a plant splits water molecules, producing oxygen. As he will explain, oxygen is a waste product — for the purposes of photosynthesis, at any rate — which the plants dump into the atmosphere. Humans and animals rely on the oxygen produced by plants.

The last speaker, Richard Sayre of Los Alamos National Laboratory, will jump to the ultimate goal of studying photosynthesis, which is to engineer alternative energy sources that can compete economically with fossil fuels. Sayre, who is chief technology officer for Phycal Inc., an algal biofuels company in which the Department of Energy has invested $50 million, will discuss the challenges of this critically important endeavor.

What’s happening in leading St. Louis labs?
Following the talks, the audience will be introduced to two local Energy Frontier Research centers, research centers focused on photosynthesis that were established by the U.S. Department of Energy’s Office of Science in August 2009. These are the Photosynthetic Antenna Research Center (PARC) at Washington University and the Center for Advanced Biofuel Systems (CABS) at the Donald Danforth Plant Center.

Demonstrations and experiments
Then comes the fun part. A video will introduce experiments PARC has designed to engage students in photosynthetic research, four of which will be set up around the room. 


Tucker Robnett, foreground, 6 of Laddonia, learns how to make algae beads from microalgae with the help of Terry Woodford-Thomas, the director of science education at the Donald Danforth Plant Science Center in St. Louis.

One demonstration, for example, will show how balls of algae change the color of a buffer as they photosynthesize. When carbon dioxide is dissolved in the water, it forms carbonic acid, turning the solution red. When photosynthesis is in high gear and carbon dioxide is being withdrawn from the water to make carbohydrate, the solution changes from red to magenta to deep purple.

A second experiment uses leaves rather than a buffer solution as an indicator. Disks punched out of leaves normally float but when the air spaces between cells are loaded with carbon dioxide (by adding sodium bicarbonate to the water), the leaf becomes heavy enough to sink. Then as the leaves begin to photosynthesize, oxygen is released into the interiors, causing them to become more buoyant and to rise.


Here, high school teachers use a spectroradiometer to see the amount of light of each color given off by different sources, such as fluorescent, incandescent and LED bulbs and, by putting the radiometer beneath a plant leaf, determine which colors the leaf absorbs.

Like many of his fellow scientists, Blankenship, the director of PARC at Washington University, thinks that children will need to be prepared to continue to solve the energy crisis, one of the top global issues today and in the future. “This guiding principle,” he said, “makes us committed to offering comprehensive energy education programs for children, teachers and the public.”

Diana Lutz
Senior Science Editor
(314) 935-5272