Figure 2

Speciation of Se in shoots of A. thaliana over-producing SMT. (A) Arabidopsis thaliana smt2-9 HCl extract injected onto a reverse phase C8 column, eluted with water:methanol (99:1 v/v) containing 0.1% TFA, and fractions analyzed for Se using ICP-MS with 83% recovery of injected Se. (B) Mass spectrum collected in the region of peak 1–3 from the chromatogram shown in Figure 2A, revealing the expected [M+H]⁺ m/z = 184 and [M+H-NH₃]⁺ m/z = 167 for MeSeCys, as well as the expected Se isotopic signature. (C) Mass spectrum collected in the region of peak 4 from chromatogram shown in Figure 2A, revealing the expected ion m/z = 313 for γGluMeSeCys, as well as the expected Se isotopic signature. (D) Arabidopsis thaliana smt2-9 HCl extract injected onto a reverse phase C8 column, eluted with water:methanol (99:1 v/v) containing 0.1% HFBA, and fractions analyzed for Se using ICP-MS with 55% recovery of injected Se.