What are optically active amino acids?

Amino acids (except for glycine, R =H below), all contain a tetrahedral carbon (asterisk), with 4 different substituents, meaning that tetrahedral C is chiral. read more

Chirality is important in context of ordered phases as well, for example the addition of a small amount of an optically active molecule to a nematic phase (a phase that has long range orientational order of molecules) transforms that phase to a chiral nematic phase (or cholesteric phase). read more

The rest of the 20 most common amino acids are optically active existing as both D and L stereoisomers. Naturally occurring amino acids that are incorporated into proteins are, for the most part, the levorotary (L) isomer. read more