The crystal structure of the extracellular domain of the LDL receptor (LDL-R) was determined in a MAD experiment using 12-tungstophosphate clusters as anomalous scatterers. While useful for phasing, the tungsten clusters rendered the crystals radiation-sensitive and non-isomorphous and profoundly altered the diffraction data, causing complications. The work is presented as a case study for phasing a medium-sized protein (700 residues) at low resolution (4 Å) with multiple non-isomorphous crystals containing 31 W atoms in the asymmetric unit.
Rudenko, G., Henry, L., Vonrhein, C., Bricogne, G., & Deisenhofer, J. (2003). ’MAD’ly phasing the extracellular domain of the LDL receptor: A medium-sized protein, large tungsten clusters and multiple non-isomorphous crystals. In Acta Crystallographica - Section D Biological Crystallography (Vol. 59, pp. 1978–1986). https://doi.org/10.1107/S0907444903021383