The research journey

Wachter’s investigations of the enzyme Rubisco activase (Rca) have helped lay the foundation for efforts in metabolic engineering of photosynthesis. Rca works in concert with Rubisco (mentioned above), and under high irradiance, Rca provides continuous support of Rubisco activity. In fact, without this activity, higher plants (e.g. crops) would perish. Under rapidly changing light conditions, Rca assists in balancing the light and dark reactions of photosynthesis.

Rebekka & Mike Salvucci

Rebekka Wachter with collaborator Michael Salvucci in 2012

Wachter, Michael Salvucci (USDA) and Associate Professor Marcia Levitus, also from the School of Molecular Sciences, have been collaborating on this project for many years, with several co-authored, highly-rated publications to their credit. Some years ago, Wachter and Salvucci published the first crystallographic paper on Rca. Subsequently, Wachter and Levitus uncovered the catalytic role of Rca subunit assembly, a regulatory mechanism that has remained enigmatic for many years.

Wachter has also collaborated with Professor William E. Moerner (Stanford, 2014 Nobel laureate in chemistry), applying state-of-the-art single molecule methods to study Rca protein-protein interactions. As a visiting scientist at the Max-Planck Institute of Biochemistry in Martinsried, Germany, in 2015, Wachter worked with renowned experts in the Rubisco field — Manajit Hayer-Hartl and Ulrich Hartl. 

Wachter’s research on GFPs has addressed questions of light capture and energy conversion in fluorescent proteins. This work has led to a more profound understanding of color acquisition by GFPs, laying the foundation for protein engineering and design efforts employed all over the world. Using green-to-red photoconvertible GFPs as a model system, her team has uncovered a direct experimental link between phenotypic change and collective protein motions.

with Marcia Levitus

Rebekka Wachter (right) with Associate Professor Marcia Levitus from the School of Molecular Science in 2018.

In collaboration with S. Banu Ozkan, a physics professor at ASU, they have described a novel evolutionary process which involves the relocation of a rigid anchoring region diagonally across the globular protein fold. This result has provided the basis for proposing a plausible step-by-step mechanism for photoconversion, a process that has remained largely enigmatic for many years. Based on earlier work, Wachter also holds a couple of patents on GFP with Roger Y. Tsien, a UC San Diego 2008 Nobel laureate in chemistry. 

Jenny Green

Clinical associate professor, School of Molecular Sciences