Fig. 2.

UAG translation in Thg1 in M. acetivorans. (A) SDS-solubilized MaThg1 mutant Pyl142Trp purified from E. coli (rTrp) and extracts of M. acetivorans expressing His-tagged Thg1 (Pyl) were analyzed by anti-His immunoblot. (B) Deconvolution of Thg1 protein purified from M. acetivorans analyzed by ESI-TOF MS. (C) MS/MS spectrum of peptide 137–148 with a Pyl at position 142 (m/z of 500.5³⁺). The location where the precursor ion is indicated by a solid diamond. Observed fragment ions (b and y) were consistent with the following McLafferty diagram: N F/V A S/O G Y Y/A/L/R where O indicates a Pyl residue.