The Life Sciences Group operates/develops user platforms that aim to enhance the quality, scope and throughput of neutron scattering studies of the structure and dynamics of biological systems. Key issues of importance are deuterium labelling, which is of primary importance to small-angle neutron scattering (SANS) studies, neutron protein crystallography, elastic incoherent neutron scattering (EINS), and neutron reflection. Other important activities are the optimisation of sample preparation procedures and the crystallogenesis requirements for large crystal.
The ability to exchange hydrogen by its heavier (and more strongly scattering) deuterium (2H or D) isotope in a way that is usually highly isomorphous offers a completely unique scope to neutron scattering studies of the structure and dynamics of biological systems in essential all relevant sample habits. Such a capability requires a range of in vivo and in vitro techniques that very difficult to maintain and develop at the laboratories of many user groups, given that the methods not easy to deploy on a one-off basis. They need continuity of expertise, economies of scale, and continuous methodology development that is driven by a combination of pressures from emerging new capabilities at the neutron facilities themselves as well as from the scientific priorities of the user communities that operate them.
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The Deuteration Laboratory (D-Lab) is run as a user platform and is part of the Life Sciences Group. It allows users in the area of life sciences and structural biology to seek tailor-made deuterated biomolecules in support of neutron scattering (D22, D11), protein crystallopgraphy (LADI-III, D19), Dynamics (IN13, IN16) and reflectometry (D17, FIGARO).
Access to the platform is by a rapid electronic peer-review system. Applicants should contact dlab-proposals@ before submitting proposals to discuss technical feasibility. ill.eu
Note that acceptance of a proposal to use the deuteration lab facility does not imply automatic allocation of neutron beamtime although the beamtime committee will be informed of the outcome of the deuteration proposal.
For neutrons, the full exploitation of protein crystallography is still strongly restrained by crystal size. Given the fluxes available at the most powerful neutron sources, this will always be a challenging aspect in delivering the huge potential that neutrons have for biological crystallography. The crucial developments for macromolecular deuteration that have occurred in the past and in dedicated facilities have resulted in a reduction of the crystal volumes needed by a factor of ~10. Macromolecular deuteration and the constant upgrades of dedicated instruments have had a very strong impact in the field of NMX (neutron macromolecular crystallography). Instruments such as LADI-III, D19 at ILL (Grenoble, France), and BIODIFF at FRM-II (Garching, Germany), are amongst the best diffractometers of their type in the world.
By the very nature of crystallisation, there is no empirical reason why conditions could not be identified that allow crystal growth to be extended. It should be a matter of putting sufficient emphasis on rational approaches for the systematic exploration of growth conditions in relation to the specific phase diagrams, but it remains a real challenge. The D-Lab team can be contacted for advice on large crystal growth of protein samples for crystallography applications.