X-ray diffraction data of CpsORN

Oligoribonuclease (ORN) is a 3 -5 exoribonuclease for small RNA molecules, important in RNA degradation and re-utilisation. However, there is no structural information on the ligand-binding form of ORNs.

In this study, the crystal structures of oligoribonuclease from Colwellia psychrerythraea strain 34H (CpsORN) were determined in four different forms: unliganded-structure, thymidine 5 -monophosphate p-nitrophenyl ester (pNP-TMP)-bound, two separated uridine-bound, and two linked uridine (U-U)-bound forms. The crystal structures show that CpsORN is a tight dimer, with two separated active sites and one divalent metal cation ion in each active site.