X-ray structural analysis

Methods / equipment

Depending on the experimental setup, we use various crystallisation techniques for crystallising our proteins and compounds, e.g.:

• Sitting drop,
• Hanging drop,
• Micro-batch under oil

as well as various executions in line with the respective task, such as

• Co-crystallisation,
• Soaking and
• Seeding

At present, we have approximately 900 different crystallisation conditions which are routinely available and can be used from the nl to µl level.

Equipment
 

• NT8® crystallisation robot
  

At present, we use three different temperatures for the crystallisation processes:

• - 4 °C, 13 °C, and 20 °C

Depending on the experiment, our proteins and compounds’ crystallisation events are analysed using manual or automated inspections.

We manage all experiments using our own LIMS (laboratory information system).

Equipment
 

• ROCK IMAGER® RI 182 (transmitted light, UV, polarisation)
• Leica S Apo stereomicroscope
• Leica M205C stereomicroscope
• 2 Peltier IPP260eco cooled incubators

Based on the initial crystallisation conditions, we optimise conditions to obtain the most suitable crystals for the subsequent data recording.

Moreover, we can also produce specific tailor-made crystallisation screens.

We, e.g., have an automatic dispenser system for these applications.

Equipment
 

• FORMULATOR® 10

First, we determine the suitable measurement conditions for the obtained monocrystals (protein crystals or crystals, small molecules).

Then, we record data sets of X-ray diffraction patterns (diffraction images) in our laboratories or using other measuring instruments.

To protect the samples, this is carried out at cryogenic temperatures (usually 100 Kelvin) but it is also available as an in-situ option at room temperature.

Equipment
 

• XtaLAB Synergy-R single crystal diffractometer (copper rotating anode)
• 4-circle kappa goniometer
• HyPix-6000HE Hybrid Photon Counting (HPC) detector
• Cryostream 800 low temperature system
• XtalCheck-S crystallisation plate adapter for in-situ crystallisation plate screening
  

• Small molecules

The recorded X-ray diffraction data enables us to construct electron density maps using complex mathematical methods. These maps are then interpreted with the help of molecule models and by using various automatic and manual processes.

The generated data can be used to answer concrete questions or to propose further structure-based optimisations of, e.g., biologicals or small molecules. 

• Small molecules
• Biologicals