Long Wavelength MX

The I23 beamline is a unique facility, used for solving the crystallographic phase problem, using the small anomalous signals from sulphur or phosphorus which are present in native protein or RNA/DNA crystals. This is of increased importance for projects where protein labelling to introduce anomalous scatterers is not feasible. In addition, the beamline's wavelength range provides access to the M-edges of elements, with huge anomalous signals offering new opportunities for phasing large molecular complexes.

The unique wavelength range also allows identification and location of lighter atoms of biological relevance such as Cl, K and Ca and assistance with low-resolution model building by locating P or S atom positions.