PSI Thesis Medal 2021 for pioneering Structural Biology at SwissFEL

The Paul Scherrer Institut is committed to scientific excellence and strongly fosters interdisciplinary research. In this spirit the PSI Thesis Medal 2021 was awarded to Dr. Petr Skopintsev from the Laboratory of Biomolecular Research at the Division of Biology and Chemistry for his pioneering experiments at the new Swiss X-ray Free Electron Laser (SwissFEL) large-scale research facility. Within an interdisciplinary team of scientists, he used time-resolved serial femtosecond X-ray crystallography (TR-SFX) to obtain structures of excited protein intermediate states at precise time points after activation to elucidate their function.

The winners of the 2020 and 2021 PSI thesis medals, Dr. Ivana Belosevic and Dr. Petr Skopintsev, with Christian Rüegg, PSI director, and Marco Stampanoni, head of the PSI research commission.

In his doctoral thesis, Petr Skopintsev focused on the KR2 (Krokinobacter Rhodopsin 2) protein, a light-driven sodium pump. Because outward pumping of Na+ can silence neuronal signaling, KR2 is considered a next-generation tool for optogenetics, a method enabling the use of light to control cellular activities (see also award of a related ERC Synergy grant in the Bio Division). In particular, Petr was intrigued by the KR2 sodium pumping mechanism as it was long debated whether such a mechanism would even exist, since Na+ was supposed to be electrostatically repulsed from a positively charged retinal chromophore base. Petr characterized the structural changes from the earliest photochemical reactions in the femtosecond range up to the biological pumping cycle concluding in the milliseconds. After initial tests at the Swiss Light Source (SLS), the work continued during the very first user run at the SwissFEL and resulted in several publications including papers in the journals “Science” and “Nature”. In his future research, Petr will focus on the structural dynamics of CRISPR-based gene editing by joining the lab of the recent Nobel Laureate Jennifer Doudna. We congratulate Petr for the well-deserved award and wish him continued success in the future.