A Superstar Enzyme is Ready for Its Close-Up in a New Generation of Synthetic Solar Fuel Catalysts

A Superstar Enzyme is Ready for Its Close-Up in a New Generation of Synthetic Solar Fuel Catalysts

The blueprints for a key enzyme have been revealed by a Yale-led team of chemists, and the blueprints could contain design principles for a new generation of synthetic solar fuel catalysts.

Cryo-electron microscopy was used on a microorganism called Synechocystis to get an extreme close-up picture of Photosystem II, the enzyme in photosynthesis that uses water as a solar fuel, allowing researchers to observe how the enzyme works.

Researchers from the University of California-Riverside, Boston College, and City University of New York collaborated on the study, which was published in the journal Proceedings of the National Academy of Sciences.

Photosynthesis is the process by which plants and certain microorganisms, such as Synechocystis, use sunlight to synthesize food from carbon dioxide and water, while also releasing oxygen into the atmosphere.

Photosystem II is a key enzyme in photosynthesis, as it oxidizes water molecules, removing their electrons for use as fuel.

By studying Photosystem II from Synechocystis, scientists have long sought ways to mimic this process in order to create more efficient solar fuel catalysts.

It’s been difficult for scientists to understand the results of their experiments without a clear picture of Photosystem II’s molecular structure in Synechocystis.

Photosytem II from Synechocystis was captured in an “immature” stage, before the enzyme was capable of water oxidation, in previous work led by Yale.

The researchers were able to gain a better understanding of how the enzyme is constructed as a result of their efforts.

The researchers were able to see the enzyme in Synechocystis in its mature, active form, complete with all of the protein subunits and activity present during water oxidation, in the new study.

The study, which was made possible by cryo-electron microscopy technology at Yale’s West Campus, provides one of the most detailed looks at Photosystem II in Synechocystis ever achieved.

“We can see, small-molecule co-factors, and water molecules that are used in the mechanism of water oxidation at this resolution,” said Brudvig, the Benjamin Silliman Professor of Chemistry in the Faculty of Arts and Sciences and director of Yale’s West Campus’ Energy Sciences Institute.

Brudvig is the corresponding author of the study.

“We can even see the contribution of individual protons in some cases,” Brudvig added.

The researchers say they’ll be able to make small changes to Photosystem II from Synechocystis, such as changing individual amino acids, to see how those changes affect the enzyme’s function.

Summary of the Brinkwire News