homochiraliteetin

Homochirality refers to a system where all chiral molecules present exhibit the same chirality. Chirality is a property of molecules that are non-superimposable on their mirror images, much like a left hand and a right hand. These mirror image forms are called enantiomers. In a homochiral system, only one of these enantiomers is present, or one enantiomer is significantly in excess over the other.

The concept of homochirality is particularly important in biology and biochemistry. Life on Earth is overwhelmingly homochiral. For example, all amino acids used in proteins are L-amino acids, and all sugars used in nucleic acids (like DNA and RNA) are D-sugars. This uniformity is thought to have arisen early in the evolution of life, providing a stable and specific molecular framework for complex biological processes.

The origin of this widespread homochirality is still a subject of active research and debate. Several hypotheses exist, including theories involving extraterrestrial seeding of chiral molecules or autocatalytic amplification of chirality on early Earth. Understanding homochirality is crucial for fields like synthetic chemistry, particularly in the development of pharmaceuticals, where the specific enantiomer of a drug can have vastly different biological effects, including therapeutic efficacy and toxicity.