dimethylarginine and alpha-cyano-4-hydroxycinnamate

We report a method to detect the presence of dimethylarginines on proteins. Peptides with dimethylarginines were hydrolyzed in acid. The hydrolysates were subjected to matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometric analysis using a mixture of alpha-cyano-4-hydroxycinnamic acid and nitrocellulose as matrix. Both asymmetric omega-N(G),N(G)-dimethylarginine and symmetric omega-N(G),N(G')-dimethylarginine give a clear signal at m/z 203. Recombinant Sbp1p modified by Hmt1p in vivo were isolated by affinity chromatography followed by electrophoresis on a polyacrylamide gel and subjected to acid hydrolysis. MALDI-TOF analysis of the acid hydrolysates confirmed the presence of dimethylarginines. The detection limit of the method is estimated at approximately 1pmol of protein.

Topics: Animals; Arginine; Blood Proteins; Collodion; Coumaric Acids; Fish Proteins; Protein Hydrolysates; Protein-Arginine N-Methyltransferases; Repressor Proteins; Saccharomyces cerevisiae Proteins; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization