Reference no: EM132439911

Problem: Determine the primary structure of a polypeptide that generates the following data with treatments as shown:

a) Acid Hydrolysis: arg, asp, 2 cys, gly, ile, leu, lys, met, phe, pro, ser

b) One round of Edman's degradation: leu and ser

c) Carboxypeptidase A: asp

d) DTT+ iodoacetic acid followed by trypsin digestion: dipeptide made of arg and ser, dipeptide made of asp and met, a hexapeptide made up of cys, gly, ile, leu, phe, pro, and a dipeptide made of cys and lys.

e) DTT+ 2-bromoethylamine followed by trypsin digestion renders a dipeptide made of arg and ser, a dipeptide made of asp and met, free cys, free lys and two tripeptides, one cys, gly, and leu and the other ile, phe, and pro. (2- bromoethylamine puts a + charge on cys, making it sensitive to trypsin digestion.

f) Chymotrypsin has no effect. ( Recognize that chymotrypsin cannot facilitate the hydrolysis of a peptide bond on the C- side of an aromatic if pro is involved in that bond)

g) Pepsin gives a nonapeptide ( arg, asp, 2 cys, gly, leu, lys, met, ser) and a tripeptide (ile, phe, pro)