Question

Sanger’s reagent is used for the identification of:
A) N-terminal of peptide chain
B) C-terminal of peptide chain
C) Side chain of amino acids
D) Molecular weight of the peptide chain
E) Number of amino acids in peptide chain

Answer 1

Hint: To solve this we must know that Sanger’s reagent is also known as 1-fluoro-2,4-dinitrobenzene or dinitrofluorobenzene. It is abbreviated as DNBF. It is named after the scientist Frederick Sanger who first used it to detect free amino acids in insulin. Sanger’s reagent can be helpful for the sequencing of proteins.

Complete step-by-step answer:
We know that Sanger’s reagent is also known as 1-fluoro-2,4-dinitrobenzene or dinitrofluorobenzene. It is abbreviated as DNBF. It is named after the scientist Sanger who used it to detect free amino acids in insulin.

Sanger’s reagent is prepared by the reaction of 1-chloro-2,4-dinitrobenzene with potassium fluoride in nitrobenzene. Sanger’s reagent appears as solid yellow coloured crystals.Sanger’s reagent is used for determining the N-terminal amino acid in polypeptide chains, in particular insulin. Sanger’s reagent reacts with amino groups in amino acids to produce dinitrophenyl amino acids. These dinitrophenyl amino acids are stable under acid hydrolysis conditions that break peptide bonds.

The structure of Sanger’s reagent is as follows:

Thus, Sanger’s reagent is used for the identification of N-terminal of peptide chain.

Thus, the correct option is (A) N-terminal of peptide chain.

Note: The pressure applied to a pure solvent so that it does not pass into the given solution by osmosis is known as the osmotic pressure. Remember to calculate the van’t Hoff factor correctly. van’t Hoff factor is the number of ions a compound can form when dissolved in water.