Scientists Have Sequenced Proteins by Using Specific Proteases to "Clip

Essay

Scientists have sequenced proteins by using specific proteases to "clip" a purified protein preparation between two specific amino acids,thus forming a number of moderately sized fragments; they have used acid hydrolysis to produce smaller fragments.Each fragment can then be sequenced by breaking the moderate fragments into dipeptides that are easily sequenced.The fragments below are obtained after the initial enzymatic cleavages.Can you deduce the sequence of the original polypeptide? (HINT: the original cleavages at specific locations differ depending on which proteolytic enzyme was used to create each fragment; this causes an overlap in the fragments' sequences.)The final polypeptide should have 18 amino acid residues.