The given question involves the reaction of a tetrapeptide, Ala-Val-Phe-Met, with Sanger's reagent, which is 1-fluoro-2,4-dinitrobenzene (FDNB). Here’s the step-by-step explanation:
- Understanding Sanger’s reagent: Sanger's reagent is used to identify the N-terminal amino acid of a peptide. It reacts with the free amino group of the N-terminal residue.
- Reaction with Ala-Val-Phe-Met: In the tetrapeptide Ala-Val-Phe-Met, Alanine (Ala) is the N-terminal amino acid. When reacted with FDNB, it forms a dinitrophenyl (DNP) derivative at its N-terminal.
- Hydrolysis of the DNP-peptide: Upon hydrolysis of the DNP-tetrapeptide, all peptide bonds are cleaved, and the individual amino acids are released. The DNP group remains attached to the N-terminal amino acid, alanine.
- Resulting in DNP-Ala: After hydrolysis, the specific product formed is 2,4-dinitrophenyl-alanine (DNP-Ala), along with free Val, Phe, and Met.
Therefore, among the given options, the correct answer is the one where the DNP group is attached to alanine.
correctly represents the product of the reaction between Ala-Val-Phe-Met with Sanger's reagent followed by hydrolysis.
Important Questions from Peptides
Partial hydrolysis of a pentapeptide yields all possible tripeptides and dipeptides. The dipeptides that are obtained upon hydrolysis are given below.
Val-Ala, Gln-His, Phe-Val and Ala-GlnThe total number of tripeptides obtained that contain 'Ala' as one of the amino acids is ________ (in integer).
A tetrapeptide, made up of natural amino acids, has alanine as the N-terminal residue which is coupled to a chiral amino acid. Upon complete hydrolysis, the tetrapeptide gives glycine, alanine, phenylalanine and leucine. The number of possible sequences of the tetrapeptide is ____________
- The structure of the dipeptide Ala-Pro derived from the natural amino acids is
