BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Amino acid isoleucine and threonine contain two chiral carbons.

Detailed explanation-2: -These two amino acids, isoleucine and threonine, have in common the fact that they have two chiral centers.

Detailed explanation-3: -Isoleucine is one of the two proteinogenic amino acids which contain a second chiral carbon atom beside the amino group-bearing -C (Bouveault and Locquin, 1905).

Detailed explanation-4: -In the case of isoleucine and threonine, both chiral centers must be inverted to generate the mirror image amino acids d-isoleucine and d-threonine.

Detailed explanation-5: -Threonine has two chiral centers and therefore four possible stereoisomers.