JEE Main · 2023 · 08 Apr 2023 · Shift 1 · Biomolecules

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Sulphur (S) containing amino acids from the following are:
(a) isoleucine
(b) cysteine
(c) lysine
(d) methionine
(e) glutamic acid

(A)a, d
(B)b, d✓ Correct
(C)b, c, e
(D)a, b, c

Answer: (B)

Solution

Only two amino acids contain sulfur: cysteine (with a thiol group

- SH

) and methionine (with a thioether group

- S - CH_{3}

). Isoleucine, lysine, and glutamic acid do not contain sulfur.

JEE Main · 2023 · 08 Apr 2023 · Shift 1 · Single correct option

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