Research group leader: Fredrik Westerlund, Associate Professor
In Fredrik Westerlund’s group, we focus on using modern nanotechnology for studies of single molecules, with main focus on DNA. Modern nanotechnology and single molecule techniques have revolutionized biophysics, and potential applications in diagnostics and medicine are becoming more and more realistic.
The DNA activities of the Westerlund group can be divided into two main research areas:
In the first we use and continue to improve an optical DNA mapping assay developed in our lab. By combining a fluorescent molecule and a molecule that only binds to AT-basepairs we form a barcode along the DNA that reflects the underlying sequence. To reveal the barcode, the DNA is stretched in the nanofluidic channels. This assay allows for fast identification and characterization of large pieces of DNA. Our current main focus is to use the assay to identify and characterize bacterial plasmids that carry genes coding for antibiotic resistance.
In the second we are using the nanochannels to study DNA-protein interactions. We have developed a lipid-based passivation scheme that allows for long time imaging of DNA-protein complexes in a way previously not possible. This opens up the possibility to investigate any DNA-binding protein that affects the physical properties of DNA. We have used this lipid-passivation of nanochannels to study both proteins that form filaments on DNA and proteins that compact DNA. Current focus is devoted to DNA-protein systems that are difficult to characterize with traditional single molecule techniques that are hampered by for example, the attachment of the DNA ends to beads or surfaces.
We are also interested in applying the nanofluidic concept to research areas beyond stretching DNA, and have recently started a collaborative project where we use the nanochannels to study biologically relevant particles such as exosomes and viruses. The nanochannels are in this project used as a parallelized nano-flowcytometer, and keep the particles in focus making it possible to observe them for extended times allowing to detect faint signals.
Furthermore, we have recent interest in using the nanochannels as a reactor in liquid-phase heterogeneous catalysis. In this project the nanochannels serve as a means of exposing the particles to controlled amounts of chemicals, to mix reagents close to the particle of interest, as well as to focus the products of the reaction for downstream analysis.
We urge potential summer students, master thesis students, PhD students and postdocs that are interested to work in the lab to contact Fredrik Westerlund, firstname.lastname@example.org!
The research is sponsored by the European Research Council, the Swedish Research Council, The Swedish Child Cancer Foundation, The Swedish Cancer Foundation, and Knut and Alice Wallenbergs Stiftelse.