Fig. 6

Polar interactions at the binding interface. a The Watson–Crick face of dU7 participates in two H-bonds with Ser61. An additional H-bond with Lys60 is mediated by W4. b The Watson–Crick face of dG11 forms H-bonds with Ile68 and Trp113. c W5 mediates hydrogen bonding between Arg16 and 2Nap-dU14