UV radiation damage-induced phasing (UVRIP)

The UVRIP method has been developed recently at EMBL-Grenoble by Raimond Ravelli and coworkers [1]. It is based on specific structural changes of cystines containing protein crystals, which is due to the irradiation with highly-intensive ultraviolet (UV) radiation. The structural changes can be used to work out a MIR-like phasing scheme [2], which can lead to precise experimental phase information. Therefore a native dataset is collected and compared with a dataset collected after the UV-irradiation of the same crystal.
We think that this method has a considerable potential as an alternative way of experimental phasing. However, due to the novelty of this method the success rate for UVRIP phasing for real-life proteins has to be determined. Thats why we are offering interested academic users the appliance of our UVRIP instrumentation and the assistance of our beamline support staff, who will provide support during the experiment as well as for the data evaluation.

Fig. 1: UV-Laser setup



Fig. 2: Protein crystal under UV-irradiation



Fig. 3: UVRIP experimental electron density at 1.7σ in blue and difference density map Fbefore-Fafter (+8σ green, -8σ red) of thaumatin at 1.4 Å resolution. The refined thaumatin structure model is shown as well.