Chapter 21, Problem 80P

Determine the amino acid sequence of a polypeptide from the following data:

Complete hydrolysis of the peptide yields Ala, Arg, Gly, 2 Lys, Met, Phe, Pro, 2 Ser, Tyr, and Val, Treatment with Edman's reagent releases PTH-Val.

Carboxypeptidase A releases Ala.

Treatment with cyanogen bromide yields the following two peptides:

1. Ala, 2 Lys, Phe, Pro, Ser, Tyr

2. Arg, Gly, Met, Ser, Val

Treatment with trypsin yields the following three peptides:

l. Gly, Lys, Met, Tyr

2. Ala, Lys, Phe, Pro, Ser

3. Arg, Ser, Val

Treatment with chymotrypsin yields the following three peptides:

1. 2 Lys, Phe, Pro

2. Arg, Gly, Met, Ser, Tyr, Val

3. Ala, Ser