A cassette recorder for the particle accelerator

A group led by TH Lübeck researcher Prof. Dr. Manfred Rößle has a new rehearsal environment for the ESRF (European Synchrotron Radiation Facility) developed, the largest electron synchrotron in Europe. In the future, users of the ID29 beam at the ESRF will be able to do the so-called Blotting tape drive from TH Lübeck use to obtain snapshot-like films of protein structures.

“The starting point for our experiment is serial crystallography,” says Mia Lahey-Rudolph, who led the study. “The atomic structure of proteins can be examined with this structural-biological method,” she explains. The high-resolution protein structure can tell researchers something about how these biomolecules work. This not only provides new insights into biology, but can also, for example, Basis for the development of tailor-made medicines form.

An important tool for analyzing the atomic structure of proteins is X-ray crystallography, in which a protein crystal is scanned with a bright X-ray beam. The crystal diffracts the X-rays in a characteristic way and thus creates a diffraction pattern. If all viewing angles of the crystal are recorded, the internal structure of the crystal and calculate the three-dimensional fold of the protein.

For most biomolecules, however, being crammed into a crystal is an unnatural state. The smaller a crystal, the more intense the X-ray light has to be to produce useful diffraction images.

“Another sticking point in these investigations is how the samples with the microcrystals get to the radiation source,” explains Mia Lahey-Rudolph. Together with Suna Precision, the researchers at the TH Lübeck constructed a device that is reminiscent of a cassette recorder “Blotting Tape Drive”. In this tape drive, a perforated polymer belt remains in constant motion and is continuously fed with fresh microcrystals, while a second belt scrapes off the solution liquid in front of the X-ray interaction zone, so that quasi-naked crystals are irradiated. “Our goal is to study time-resolved structural changes induced by light activation, ligand mixing or pH jumps in the crystallized proteins very quickly and with a high signal-to-noise ratio,” explains Mia Lahey-Rudolph, a scientist at the TH Luebeck.

Thanks to funding from the TH Lübeck, the research team Federal Ministry of Education and Research get the opportunity to improve the measurement setup in cooperation with the ESRF. The ESRF is based in Grenoble, France and attracts researchers from all over the world at.