Question

What are the products from treatment of the following peptide with trypsin? (Table of protease recognition sites) Leu-Val-Ala-Arg-Phe-Val-Ala-Leu-Lys-Gly-Arg-Pro-Asp

a) Leu-Val-Ala-Arg
b) Phe-Val-Ala-Leu
c) Lys-Gly-Arg-Pro
d) Asp

Answer 1

Upon treatment with trypsin, the peptide sequence provided would be cleaved into the following products: Leu-Val-Ala-Arg, Phe-Val-Ala-Leu, Lys-Gly-Arg-Pro, and Asp, due to trypsin's specificity for lysine and arginine residues.

Step-by-step explanation:

The student's question pertains to the activity of trypsin on a specific peptide sequence. Trypsin is a protease that cleaves peptides at the carboxyl side of lysine and arginine except when either is followed by proline. Given the peptide sequence Leu-Val-Ala-Arg-Phe-Val-Ala-Leu-Lys-Gly-Arg-Pro-Asp, trypsin treatment would result in the following products:

• Leu-Val-Ala-Arg
• Phe-Val-Ala-Leu
• Lys-Gly-Arg-Pro
• Asp

Each product is generated because trypsin cleaves after the arginine and lysine residues present in the sequence, unless the next residue is proline.