Fig. 9.

ESI-MS spectra of the hGrx-1 tryptic peptide DCIGGCSDLVSLQQSGELLTR obtained from a Grx-1/EdAG mixture (50 μM Grx-1+1 mM EdAG) incubated for 24 h at 37 °C in PBS, pH 7.4 and in presence of 250 μM TCEP. The observed molecular weight indicates that the peptide contains two carbamidomethyl derivatives (CAM) of the cys residues as a result of reaction with iodoacetamide. The result was confirmed by high mass accuracy MS/MS data (not shown).