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JEE Main · 2023 · 29 Jan 2023 · Shift 2 · Biomolecules

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Following tetrapeptide can be represented as
(F, L, D, Y, I, Q, P are one letter codes for amino acids)
  1. (A)FIQY
  2. (B)FLDY✓ Correct
  3. (C)YQLF
  4. (D)PLDY

Answer: (B)

Solution

Reading the chain from the free amino end towards the free carboxyl end, the first residue bears a benzyl side chain and is phenylalanine, the second bears an isobutyl side chain and is leucine, the third bears a carboxymethyl side chain and is aspartic acid, and the fourth bears a para-hydroxybenzyl side chain and is tyrosine. Written with the one-letter codes in this order, the tetrapeptide is FLDY.
Structure Phenylalanine
Phenylalanine
Structure Leucine
Leucine
Structure Aspartic acid
Aspartic acid
Structure Tyrosine
Tyrosine

JEE Main · 2023 · 29 Jan 2023 · Shift 2 · Single correct option

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