Epimerases

Part of speech: noun

Definitions

1. An enzyme that catalyzes the conversion of one epimer to another, facilitating the change in configuration around a specific stereocenter in a molecule
2. A type of enzyme responsible for altering the stereochemistry of a compound, particularly affecting the arrangement of atoms at a chiral center
3. A biochemical catalyst that facilitates the interconversion of epimers, which are stereoisomers differing at one specific carbon atom

Etymology: Epimerases are enzymes, and the word is a chain of coinages built from Greek pieces. The core is "epimer," a term for molecules that differ from one another only in the arrangement around a single carbon atom. "Epimer" combines Greek "epi-" (upon, over) with "meros" (part), so the idea is a part sitting over or beside another. The "-ase" ending, borrowed from the name of the first enzyme ever identified, "diastase," marks the word as an enzyme name. Its ancestry runs through "diastase," itself built from Greek "dia" (through, apart) and "stasis" (standing), which was adopted into English in the nineteenth century. Because "epimerase" is a modern scientific coinage, it has no classical use behind it: the Greeks who made "meros" and "epi" never encountered these molecules. The plural form simply adds "-s" to the English noun, so "epimerases" names more than one such enzyme.

Synonyms: isomerases, enzymes, epimerizing enzymes