Optimization of Nonenzymatic Microwave D-Cleavage and Disulfide Bond Cleavage
نویسنده
چکیده
A nonenzymatic digestion technique allows proteins to be well suited for collision-induced dissociation tandem mass spectrometry. This method utilizes microwaves and Dithiothreitol (DTT) to selectively cleave at aspartic acid (D) and disulfide bonds. This microwave digestion technique is reproducible and produces peptides with a shortened sequence length. Insulin I is used in this study to optimize the disulfide bond cleavage, and α -lactalbumin is used as a test-piece for the combined D-cleavage and disulfide bond cleavage technique. The digested samples in this study are analyzed using Matrix Assisted Laser Desorption (MALDI). Through optimization with pH, time, temperature and DTT concentration, a spectrum of ideal parameters for these techniques was found.
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