Angiotensin II a hormone involved in the regulation of blood

Angiotensin II, a hormone involved in the regulation of blood pressure, is an octapeptide composed of eight different amino acids.

Reaction of angiotensin II with 2,4-dinitrofluorobenzene followed by complete hydrolysis of the peptide gives aspartic acid (Asp) labeled with 2,4-dinitrophenyl (DNP) group.

Angiotensin II is cleaved by chymotrypsin to give two tetrapeptides (peptide X and peptide Y).

Peptide X: Contains arginine (Arg), aspartic acid (Asp), tyrosine (Tyr), and valine (Val); it is cleaved by trypsin into two dipeptides.

Peptide Y: Partial hydrolysis gives phenylalanine (Phe) and the tripeptideIle-His-Pro.

Give the sequence of amino acids in angiotensin II using 3-letter codes for the amino acids (listed below).

Arginine (Arg), Aspartic Acid (Asp), Isoleucine (Ile), Histidine (His), Phenylalanine (Phe), Proline (Pro), Tyrosine (Tyr), Valine (Val)

Please give as detailed of an answer as possible, I have an answer, but am unsure if it is correct! - Thanks!

Solution

Asp-Arg-Val-Tyr-Ile-His-Pro-Phe - His-Leu

Chymotrypsin cleaves the peptide bond when the C terminal is donated by tyrosine,Tryptophan and phenyl alanine.

So the sequence is peptide X Asp-Arg-Val-Tyr

Petide Y is Ile-His-Pro-Phe and His-Leu

The 3 letter codon is