A protein ' X ' with molecular weight of $70,000 \mathrm{u}$, on hydrolysis gives amino acids. One of these amino acid is

JEE Main · 2023 · 31 Jan 2023 · Shift 1 · Biomolecules

A protein ' X ' with molecular weight of

70, 000 u

, on hydrolysis gives amino acids. One of these amino acid is

(A)(see structure)
(B)(see structure)
✓ Correct
(C)(see structure)
(D)(see structure)

Answer: (B)

Solution

Proteins are polymers of

α

-amino acids, in which the amino group is on the carbon next to the carboxyl group. Of the structures shown, only the one with

- N H_{2}

on the

α

-carbon,

(CH X_{3}) 2 C H - C H 2 - C H (N H 2) - C O O H

, is an

α

-amino acid and can come from hydrolysis of a protein. The amino acid is leucine.

JEE Main · 2023 · 31 Jan 2023 · Shift 1 · Single correct option

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