Crystallisation of Macromolecules
The crystallisation of proteins is a bottleneck in the structural determination by X-ray diffraction. Since the crystallisation of proteins is a multi-factorial process that depends on the interplay of several independent parameters, such as temperature, protein concentration, crystallisation agent concentration, pH and the presence and nature of impurities or additives, it is usually necessary to carry out crystallisation screenings to determine the optimal crystallisation conditions. At the Crystallisation Factory we offer two main techniques for the screening of crystallisation conditions of single proteins and macromolecular complexes: vapour diffusion and counter diffusion.
Nanodrop crystallisation robot (Hamilton Instruments). It allows the setting up of crystallisation screens by the sitting drop vapour diffusion method and consists of the following components: a) a Microlab Star Plus equipment with a dual arm system with 8-channels (1000 µl), a Co-Re-96 Head (300 µl), a Co-re Grip, a nanopipettor, an iSwap arm and a thermo-sealer; b) screen_developer dedicated software, which comes with pre-programmed software methods for the design of refinement screens.
Counter diffusion Crystallisation kits (Triana Scienc & Tech). The more advanced counter diffusion kits of the market (GCB-Domino) allow a complete screening of the phase diagram taking advantage of the full potential of the counter diffusion technique.
All crystallisation screenings include the analysis of the concentration and quality of the protein or complex in terms of purity and homogeneity by SDS PAGE. Additionally, all the crystallisation experiments are followed by optical microscopy after 24 hours, 3 days, 1 week and 3 weeks.
1) For those who do not know where to start their crystallisation experiment, we have designed three packs of crystallisation screenings according to the technique employed:
Screening Pack of crystallisation by vapour diffusion (30 µL of sample): This pack is based on the sitting drop vapour diffusion technique and includes three plates of 96 crystallisation conditions each.
Screening Pack of crystallisation by counter diffusion (12 µL of sample): This pack is based on the counter diffusion technique and includes an exhaustive screening of concentrations of 36 conditions.
Combined Screening Pack of crystallisation (28 µL of sample): This pack combines 24 conditions by the counter diffusion technique and three plates of 96 conditions each by the vapour diffusion technique.
2) For those who know exactly what kind of screenings of crystallisation would like to run, we offer a variety of crystallisation plates based on the vapour diffusion technique:
Crystallisation plates: It is possible to select any number of desired plates.
3) Alternatively, you can contact us and we will advise you on the best choice for your protein or protein complex.