Question

Which specific reagent did Sanger use in 1955 to study the structure of insulin?

• A. Ninhydrin
• B. Phenylisothiocyanate
• C. Fluorodinitrobenzene
• D. Biuret Reagent

Hint:

{Sanger’s reagent} = {1-fluoro-2,4-dinitrobenzene (FDNB)}. It is used to identify the {N-terminal amino acid} of proteins.

Answer 1

The Correct Option is C

Concept: Frederick Sanger was the first scientist to determine the complete amino acid sequence of a protein, which was insulin, in 1955. His work was a major milestone in biochemistry and earned him the Nobel Prize in Chemistry. To identify the N-terminal amino acid of insulin, Sanger used a specific chemical reagent called 1-fluoro-2,4-dinitrobenzene (FDNB), also known as Sanger’s reagent.
Step 1: Identify the reagent used by Sanger in studying insulin structure.

• Ninhydrin – Used to detect amino acids.
• Phenylisothiocyanate – Used in Edman degradation.
• Fluorodinitrobenzene – Sanger’s reagent used to identify N-terminal amino acids.
• Biuret Reagent – Used to detect peptide bonds.

Therefore, the reagent used by Sanger to study insulin structure was Fluorodinitrobenzene (FDNB).