Endorphins were isolated from the pituitary gland in 1976. They are potent pain relievers. -Endorphin is a

Question:

Endorphins were isolated from the pituitary gland in 1976. They are potent pain relievers. β-Endorphin is a polypeptide containing 32 amino acid residues. Digestion of b-endorphin with trypsin gave the following fragments:
Lys
Gly-Gln
Asn-Al-His-Lys
Asn-Ala-Ile-Val-Lys
Tyr-Gly-Gly-Phe-Leu-Met-Thr-Ser-Glu-Lys
Ser-Gln-Thr-Pro-Leu-Val-Thr-Leu-Phe-Lys
Using this information only, what is the C-terminal amino acid of b-endorphin?
Treatment with cyanogen bromide gave the hexapeptide
Tyr-Gly-Gly-Phe-Leu-Met
and a 26 amino acid fragment. With this information, what is the N-terminal amino acid of β-endorphin?
Digestion of β-endorphin with chymotrypsin gave, among other fragments, a 15-unit fragment identified as
Leu-Met-Thr-Ser-Glu-Lys-Ser-Gln-Thr-Pro-Leu-Val-Thr-Leu-Phe
You should now be able to locate 22 of the 32 amino acid units. Write out as much as you can of the sequence. What further information do you need to complete the sequence?