Crystallization

X-ray crystallography is the method of choice for solving the structure of molecules with the size up to 1 MDa, while most typical systems consist of ordered domain structures from few 100 kDa to peptides and small molecules. Crystallography is the most popular structural biology method in use. The main requirement is that your sample is ordered and pure enough to crystallize. Macromolecular crystallization requires few milligrams of purified protein, and can yield higher resolution structures than any other technique.

The X-ray crystallography unit offers standard and optimized crystallization screens, including lipid phase crystallization of membrane proteins. The unit also jointly organizes the shipment of crystals and data collection at synchrotrons by coordinated Block-Allocation-Group (BAG)-proposals, ESRF and MAXLAB-IV (Kajander, Helsinki) and Diamond (Lehtiö, Oulu) on the national level of Instruct-FI. New in situ crystallization screening is available in-house (Rigaku XtaLAB Syn­ergy-S X-ray Dif­fracto­meter Sys­tem), facilitating rapid evaluation of crystal diffraction.

Robots are key to the expansion of macromolecular crystallography. They can accurately handle nanolitre volumes and perform the crystallization experiments using only 5-10% of the protein volumes required for manual setup. The small drops also equilibrate faster, allowing for quick results.

For each 96-formatted screen, we ask users to provide a minimum volume of 20 ul concentrated (typically 5-20 mg/ml) protein sample. We prepare the sample for crystallization, dispense all crystallization solutions and protein drops on the crystallization plate, seal plates and image the experiment. Users will be able to check the images and the history of each drop by gaining access to PiXray or IceBear software for viewing and scoring crystallization results through any internet browser (firefox, chrome etc).