Question

Which of the following is not optically active?
1. Glycine
2. Alanine
3. Serine
4. All of the above

Answer 1

Correct Answer - Option 3 : Serine

The correct answer is Serine.

• Serine
  • Serine is not optically active.
  • It is a non-essential amino acid present in our human body.
  • Serine is present and functionally important in different types of proteins.
  • This compound is one of the naturally occurring proteinogenic amino acids.
  • Only the L-stereoisomer comes out naturally in proteins.
  • It is not essential to the human diet, since it is synthesized in the body from other metabolites, including glycine.
  • Serine was first acquired from silk protein, a particularly rich source, in 1865 by Emil Cramer.

• Glycine
  • Glycine is an amino acid that has a single hydrogen atom as its side chain.
  • It is the simplest amino acid, having the chemical formula NH2‐CH2‐COOH.
  • Glycine is one of the proteinogenic amino acids.
• Alanine
  • Alanine is an α-amino acid that is consumed in the biosynthesis of proteins.
  • It contains an amine group and a carboxylic acid group, both adjacent to the central carbon atom which also carries a methyl group side chain.