Uridine as a new scavenger for synchrotron-based structural biology techniques.
Crosas, E., Castellvi, A., Crespo, I., Fulla, D., Gil-Ortiz, F., Fuertes, G., Kamma-Lorger, C.S., Malfois, M., Aranda, M.A., Juanhuix, J.(2017) J Synchrotron Radiat 24: 53-62
- PubMed: 28009546 
- DOI: https://doi.org/10.1107/S1600577516018452
- Primary Citation of Related Structures:  
5L9J, 5LA5, 5LA8, 5LAF, 5LAG, 5LAN - PubMed Abstract: 
Macromolecular crystallography (MX) and small-angle X-ray scattering (SAXS) studies on proteins at synchrotron light sources are commonly limited by the structural damage produced by the intense X-ray beam. Several effects, such as aggregation in protein solutions and global and site-specific damage in crystals, reduce the data quality or even introduce artefacts that can result in a biologically misguiding structure. One strategy to reduce these negative effects is the inclusion of an additive in the buffer solution to act as a free radical scavenger. Here the properties of uridine as a scavenger for both SAXS and MX experiments on lysozyme at room temperature are examined. In MX experiments, upon addition of uridine at 1 M, the critical dose D 1/2 is increased by a factor of ∼1.7, a value similar to that obtained in the presence of the most commonly used scavengers such as ascorbate and sodium nitrate. Other figures of merit to assess radiation damage show a similar trend. In SAXS experiments, the scavenging effect of 40 mM uridine is similar to that of 5% v/v glycerol, and greater than 2 mM DTT and 1 mM ascorbic acid. In all cases, the protective effect of uridine is proportional to its concentration.
Organizational Affiliation: 
ALBA Synchrotron, Carrer de la llum 2-26, 08290 Cerdanyola del Vallès, Barcelona, Spain.