Determination of Trx-Ac-Var-1 and Ac-Var-1 Mass

The molecular mass and homogeneity of recombinant Trx-Ac-Var-1 and the active Ac-Var-1 peptide were determined using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). For the Trx-Ac-Var-1, a linear time-of-flight mode was performed and for the acid-digested Ac-Var-1 peptide both linear and reflector mode was performed for high resolution using Applied Biosystems/MDS SCIEX 4800 MALDI TOF/TOF™ Analyzer (Waltham, MA, USA). The samples were run in positive detection mode using alpha-cyano-4-hydroxycinnamic acid as the matrix. Internal mass calibration of the instrument with known standards was used.