Question

Sulphur containing amino acid is

• A. Methionine
• B. Cystine
• C. Cysteine
• D. All the above

Answer 1

The correct option is D All the above

The proteins are made up of amino acids. The amino acids are linked together by peptide bonds to form a protein.

Methionine is the sulphur containing amino acid. It has C${}_5$H${}_{11}$NO${}_2$S. It helps in the initiation of the protein synthesis.

Cystine is a dimer which is obtained by oxidation of cysteine. The molecular formula is C${}_6$H${}_{12}$N${}_2$O${}_4$S${}_2$.

Cysteine is a semi essential protein. Serine acts as a precursor and the sulfur is derived from methionine. The molecular formula is C${}_3$H${}_7$NO${}_2$S.

So, the correct answer is option D.