Orientera exploderande proteinmolekyler

Tidsperiod: 2019-01-01 till 2024-12-31

Projektledare: Carl Caleman

Finansiär: Vetenskapsrådet

Bidragstyp: Bidrag för anställning eller stipendier

Budget: 12 000 000 SEK

Single particle imaging using subpicosecond intense pulses from X-ray lasers has been identified as a path to obtain high-resolution images of proteins or viruses, without the need of crystallization. Avoiding the crystallization step would simplify the structural determination, and provide great progress in the determination of structure of the large and important number of difficult-to-crystallize molecules, such as membrane proteins.A sample exposed to the extreme condition generated by the X-ray laser will undergo ionization leading to electronic redistribution and destruction of the molecular structure. To be able to obtain high-resolution data from X-ray laser biomolecular experiments, the damage process must be understood. By using a velocity map imaging instrument (VMI) and combining it with a angularly-resolved time-of-flight electron spectrometer (an ARToF, developed at our division) we will be able to measure the angular distribution of the ions and electrons ejected from molecules ionized by an XFEL pulse. This will generate information about the electronic and nuclear dynamics, which we will combine with theoretical studies. This has the potential to answer two important questions: i) How do the electronic and atomic dynamics affect the diffracted signal during the X-ray exposure?, and ii) Can the sample orientation be retrieved by studying the angular distribution of the molecular fragments ejected in the explosion caused by the X-ray laser pulse?