For specific projects nation-wide, NORSTRUCT can offer competence and technical services for 3D structure determination. The services are offered free of charge for all academic users. This will include preliminary testing of suitability for structure determination, crystallisation, and X-ray data collection and analysis using local or synchrotron radiation sources. For delivery of protein samples, see checklist.


Specific service tasks offered by NORSTRUCT:

Preliminary tests
• DLS - testing aggregation and oligomerization (DLS: Dynamic Light Scattering)
• DLS - testing microheterogenety
• DLS - testing temperature dependency



Crystallization experiments
• Robotic crystallization trials with up to 5 different standard crystallization screening kits
• Optimization of conditions based on screens
X-ray testing of crystals
• Diffraction quality tests with conventional X-ray sources
• Diffraction quality tests using synchrotron sources
• Tests of cryogenic conditions


Data collection
• Data collection using conventional X-ray sources on well-behaving crystals.
• Data collection using synchrotron sources on well-behaving crystals
• Integration and processing of the diffraction data

The capacity for these services is high, and we foresee that we will be able to serve all the needs in Norway.

However, when a native data set is obtained from routine procedures as indicated above, the NORSTRUCT service is ended for that particular protein. If NORSTRUCT is to continue with structure determination, or when a much more thorough investigation has to be carried out for the preliminary tests or for obtaining crystals, this must be in collaboration with NORSTRUCT.

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For collaboration projects NORSTRUCT can solve the three dimensional structure e.g. by

Molecular replacement if structural homologues are known

Perform heavy atoms soaks with the crystal or use Se-Met protein and thereafter collect:

- High multiplicity single wavelength anomalous dispersions (SAD) data at the absorption edge of the heavy atom.
- Multiple wavelength anomalous dispersion (MAD) data at and around the absorption edge of the heavy atom.
- Or use the Multiple isomorphous replacement (MIR) method to solve the structure.

After the structure has been solved, structural comparison can be performed.

Often the protein structure can be used to explain the biochemical behavior of the protein like:

melting temperature

protein stability

catalytic temperature optimum