Skip to main content
. Author manuscript; available in PMC: 2013 May 1.
Published in final edited form as: Plant Biol (Stuttg). 2011 Nov 25;14(3):420–427. doi: 10.1111/j.1438-8677.2011.00513.x

Fig. 6.

Fig. 6

Tandem mass spectrum of a triple-charged precursor ion with mass per charge ratio (m/z) of 754.5048, observed during the LC-MS/MS analysis of the tryptic digest of spot 16 (see Fig. 4). Database searching identified this spectrum as corresponding to the peptide spanning residues 80–98 of the small Ras-related GTP binding protein of Brachypodium (theoretical mass of the triple protonated peptide would be 754.6821; measured mass error −0.18 Da). Fragment ions labelled as yn are C-terminal fragment ions, where the number corresponds to the number of amino acids present. Ions labelled as bn are N-terminal ions containing the indicated number of amino acids. The fragments observed are annotated on the peptide sequence as angled marks. Amino acids in the sequence are indicated using their one-letter abbreviations: C*, carbamidomethyl cysteine; M*, oxidised methionine; MH2-SOCH42+, side-chain loss of oxidised methionine from precursor ion.