摘要:
The newly discovered S-geranylated 2-thiouridines (geS2U) (Dumelin et al., 2012) and 2-selenouridines (Se2U) were recently shown to be synthesized by a single enzyme (selenouridine synthase, SelU) through two distinct pathways using the same 2-thiouridine substrate (S2U); however, no clear catalytic mechanism was proposed. We suggest that S-geranyl-2-thiouridine is an intermediate of the SelU-catalyzed conversion of S2U to Se2U. The successful chemical transformation of S2U -> geS2U -> Se2U is demonstrated here as an initial approximation of the intracellular pathway. The structure of Se2U was confirmed by spectroscopic methods, which included, for the first time, Se-77 NMR data (delta 354 ppm). (C) 2014 Elsevier Inc. All rights reserved.