Deuteration and Macromolecular Crystallisation (DEMAX)

Deuteration of biomolecules is achieved by culturing cells under deuterated conditions, harvesting the cell paste, and then processing or extracting the desired products. Deuterated products can include polysaccharides, proteins, lipids, and DNA/RNA. In some cases the extracted materials can be used for the derivation of other deuterated biomolecules. DEMAX will support cell paste production from a number of organisms (yeast, certain algal strains, bacteria), protein purification using liquid chromatography, some characterisation (DLS, SDS-PAGE, UV/Vis, thermal stability) and deuterium incorporation if feasible. For other types of biomaterials, molecules are purified using basic chemical methods: solvent extraction, chromatographic purification (FPLC, HPLC) and their purity/composition is analysed using standard methods (such as gas chromatography (GC) with flame ionisation, GC-mass spec, and NMR).

Small angle scattering, spin echo, reflectometry, and protein crystallography are fast growing areas in soft matter and life science that have a need for these kinds of materials. For protein crystallography there is an enormous benefit to using deuterated proteins. Not only does deuteration boost the signal-to-noise ratio, it also allows for much smaller (~10 times) crystal volumes required. These labeled biomaterials can be fully, partially or selectively deuterated, as required for a particular experiment.

Chemical deuteration of small molecules can be achieved through a range of methods, and the modification of deuterated molecules using synthetic chemistry techniques allows a broad range of deuterated molecules to be synthesised. The ESS chemical deuteration laboratory is equipped to produce and modify a range of deuterated small molecules including lipids, surfactants and monomers.

ESS also focuses on the development of new techniques for deuteration chemistry, including enzyme-catalysed synthesis of challenging small molecules, and the chemical or enzymatic modification of biologically-produced materials.

Large crystals (at least 0.1–0.5 mm³) are required for successful neutron protein crystallography experiments. Most crystals that are able to grow to 200-300 microns without explicit effort and often can be coaxed to larger sizes. This requires detailed knowledge of protein properties, the right approach, and tools. Using larger crystals offers additional advantages: higher quality data, higher resolution data, faster data collection times, and they are easier to manipulate. So, while ESS flux and beam characteristics will lower the required size, it is still advantageous to maximise the crystal volume. DEMAX will offer integrated support for protein production to large crystal growth. Included is access to an Opticrys dialysis crystallization device, Oryx8 screening robot, microbatch and macrobatch support, large volume vapor diffusion set-ups, and a variety of temperature-controlled incubators for temperature-ramping experiments.