ASU Research E-Magazine: Popeye Power for the Future

Remember Popeye, the squinty-eyed cartoon sailor with bulging forearms and a corncob pipe? Popeye always had a ready solution when he needed an infusion of instant energy.

He simply gobbled down a can of spinach.

Earlier this year, ASU scientists combined biology and electronics to create the world’s first bionic photosynthetic energy system. They used an enzyme of spinach to get the job done. The researchers built a cell-like machine that mimics biological photosynthesis, the process that powers all green plants on Earth.

ASU chemists Ana Moore, Devens Gust, and Thomas Moore reported their work in the April 2 issue of the international journal Nature. They developed their system with assistance from ASU postdoctoral researchers Gali Steinberg-Yfrach and Edgardo Durantini, and with Jean-Louis Rigaud of the Curie Institute in Paris, France.

The new system duplicates a plant’s ability to capture energy from sunlight and harnesses this energy for human manipulation. The scientists built an artificial membrane-based system that uses light to power the production of adenosine triphosphate (ATP). ATP is the carrier of chemical energy in all living organisms.

To mimic nature’s biological engine, the scientists devised a chemical system that pumps protons across a membrane from the outside of a cell to the inside. The pumping action creates an imbalance in proton concentration across the membrane. As a result, the protons flow through a protein and generate biological energy.

“Our focus was on how to capture solar energy and convert it to a useful form in the same way that photosynthesis does,” Gust explains. “We are tying to see how far we can go in mimicking the way photosynthetic bacteria convert light energy into ATP chemical potential. Living organisms have been doing this for billions of years. But this is the first time humans have been able to get it to work.”

The technology has potential ramifications that rival the way 1960s semiconductor research at Stanford University led to the birth of the Bay Area’s Silicon Valley. “The photosynthesis research at ASU could help to drive the 21st century economy of central Arizona,” says Jonathan Fink, ASU’s interim vice provost for research.

The Moores, Gust, and dozens of ASU students have experimented with artificial photosynthesis for 20 years. During the past 18 months, they have validated the ability to copy the process of capturing light energy, the first step in developing an artificial power system. —Dennis Durband