Research group
Structural dynamics of aqueous solutions (SDAQS)
In the group we are interested in understanding role of water in chemical and biophysical processes from a statistical physics perceptive. We study the structural dynamics of aqueous solutions, including nanoparticles, organic molecules and proteins in supercooled and glassy states.
We combine state of the art experiments at X-ray facilities with high performance computing data analysis techniques and molecular dynamics simulations to reach a deeper mechanistic insight.
Our experiments involve the use and development of coherent scattering techniques at large scale X-ray facilities such as synchrotrons, such as the MAX IV, and X-ray free-electron lasers (XFELs) like the European XFEL. We specialize in X-ray Photon Correlation Spectroscopy (XPCS) and time-resolved X-ray Scattering as methods for following structural dynamics in solutions, using hard X-rays. In addition, we develop X-ray compatible sample environments and employ in-house setups such as dynamic light scattering, X-ray diffraction and IR spectroscopy.
The scientific objective of this RAC consortium is to use advanced X-ray methods in order to study the dynamics of proteins in crowded environments, in condensates and during phase transitions on their relevant length and time scales.
The inside of a cell is packed with proteins, RNA, and other biomolecules. Researchers have discovered that this crowding in the cell results in a kind of condensate of biomolecules, like small molecular droplets, which appear to be important for the cell’s function
PRISMAS – PhD Research and Innovation in Synchrotron Methods and Applications in Sweden – is a new doctoral
programme training the next generation of leading synchrotron experts.
Resolving and controlling the biomolecular condensation mechanism is essential for understanding cellular function, as well as for treating aggregation diseases and facilitate the formulation of future protein-based drugs and materials.
Dynamical heterogeneities (DyHes) emerge in liquids upon cooling, when molecules form regions with distinct slow and fast dynamics. Even though DyHes are ubiquitous across research fields, they have so far eluded direct experimental observation.
Researchers uncover how glycerol, a common cryoprotectant, manipulates water's behavior at extremely low temperatures to prevent ice formation. The study, published in Nature Communications, provides a deeper understanding of the complex interplay between glycerol and water, with profound implications for cryopreservation – the science of preserving biological materials at ultra-low temperatures. This is an international research effort, led by Stockholm University (SU), in collaboration with Pohang University of Science and Technology (Republic of Korea), RIKEN SPring-8 Center (Japan) and Brooklyn College of the City University of New York (USA).
Anita Girelli is a new fellow in the Marie Skłodowska-Curie Actions program from the European Commission in 2024. Originally from Verona in Italy, Anita came to Fysikum in 2022 to start her first postdoc with Foivos Perakis. The way from Italy to Sweden was not always straight forward. For one, Anita took some time to fall in love with physics— I always liked math but at my first contact with physics, I thought it was weird and boring.
Foivos Perakis was born and raised in Athens, Greece. Already at high school he was attracted to math, physics or computer science. During his studies at the Physics department at the University of Crete, he took the opportunity to study as an ERASMUS student at the University of Amsterdam. Later on, Foivos did his PhD in University of Zurich and a postdoc at Stanford. In 2016 he moved to Sweden as a researcher at Fysikum. He was appointed as an assistant professor in 2019 and a Wallenberg Fellow in 2023. His research group focuses on liquid-liquid transitions and proteins in crowded and cryogenic environments.
Proteins carry out a wide range of important functions in our bodies. Knowledge about how they move around and through the crowded environments of our cells and tissues is key to understanding how they perform these crucial functions. Experiments exploring protein dynamics, however, often use samples that do not reflect the crowded and complex environments of the cell. At the European X-ray Free Electron laser (XFEL), scientists carried out X-ray photon correlation spectroscopy experiments to measure the nanoscopic structural dynamics of protein solution samples. The results, reported in Nature Communications open up the unique possibility of studying collective dynamics in protein solutions with high concentration, which is particularly interesting in the context of intracellular transport in eukaryotic cells and in drug design.
