The KIF Prize 2021 is awarded to Christina Kjær from Aarhus University
Congratulations on being awarded the KIF Prize 2021!
You are a postdoctoral researcher at the Department of Physics and Astronomy at Aarhus University, and in a sense, you are just starting your career as a scientist. In their motivation, the prize committee have emphasized how impressed they are with your scientific contributions at such an early stage. Would you please tell us about your research and some of your results so far?
Thank you! I am very honored to receive this award!
In my research, I study the absorption and fluorescence by large molecular ions isolated in gas phase – preferable biomolecules important in biological processes, such as the light-harvester in green plants (chlorophyll) or the molecule responsible for light-emission from fireflies (oxyluciferin). These biomolecules are often located in protein pockets where interactions with the surrounding environment (amino acids or single water molecules) tune the transition energy (color) and the ability to fluoresce. By studying the biomolecules isolated in the gas phase, I obtain knowledge about the intrinsic properties and deduce the effect of the microenvironment. I have used this approach to study isolated chlorophyll. First, to establish the intrinsic transition energy (color) and subsequently to identify interactions in the protein that tune the color.
Taking a light-emitting species out of the protein pocket can significantly reduce or even turn off the fluorescence, which unfortunately makes it impossible to establish the “intrinsic” color of the emitted light. However, the fluorescence can in some cases be turned on by cooling of the biomolecule. Recently, I have constructed a unique instrument (LUNA2) for fluorescence measurements on isolated and cold ions in vacuo, which enables us to study fluorescence from a wider range of biomolecules and protein biochromophores.
Where have you studied and which positions have you held before your current one?
I studied at the Department of Physics and Astronomy at Aarhus University (AU) both for my master’s and PhD degree. During my PhD I spent over three months at the Department of Chemistry at Melbourne University which was an educative and very fun experience. Also, I have visited Bar-Ilan University in Israel to do experiments. After I obtained my PhD degree in 2019, I was a postdoc in the group of Lars H. Andersen also at AU and now I am in the group of Steen Brøndsted Nielsen at AU.
What was your motivation to pursue a career in physics and how did you choose the field you are now specialized in?
My motivation to study physics was based on a general interest in science that expanded through high school where I had excellent teachers in both chemistry and physics. I was fascinated by the fact that some parts of physics are just hard to grasp and that drew me in. I liked the challenge! Soon after I started at the university, I realized that I wanted to do more experimental work, so I did some minor experimental projects in a handful of different laboratories. I found the experiments on interactions between biomolecules and visible light particularly interesting and returned to this field for my master’s thesis project. I was happy with the work and my team so when I was offered to continue as a PhD student, I happily accepted.
One of the purposes of the KIF prize is to help identify and highlight female physicists as role models. Have you yourself had role models or mentors? If so, what inspiration did you get from them?
During the last 10+ years, I have met many talented fellow students, teachers and researchers who have all inspired me. One of them is my PhD supervisor with whom I have had a long and fruitful collaboration. Early on, he believed in me to be capable of solving problems or managing tasks that I myself doubted that I could do. I learned that often my doubts were unfounded and even when I found myself struggling, I managed to find a solution along the way. This has given me the courage to plunge into uncharted territories without second thoughts.
At what age did your interest in science start and what prompted it?
I was always a curious child who challenged my parents with questions like why is the sky blue? or what are rainbows made of?
What advice would you give to other young people (in particular women and minorities) who dream of pursuing a career in science?
Go for it! In my experience, teamwork and idea development thrive when team members have different backgrounds and skillsets, so do not be discouraged if you do not fit into the typical scientist archetype.