Metalloenzyme

Part of speech: noun

Definitions

1. A biological catalyst that contains one or more metal ions integral to its structure and function; an enzyme whose activity depends on metal cofactors; a protein molecule that facilitates chemical reactions by coordinating metal ions within its active site
2. An enzyme protein incorporating metal ions which are essential for catalytic activity; a metal-dependent biological catalyst facilitating specific chemical transformations; a metalloenzyme is a protein structure that binds metals to drive enzymatic reactions
3. A specialized enzyme that requires metal ions bound within its structure to perform catalysis; a biologically active protein coordinating metal cofactors critical for reaction facilitation; a catalyst in living organisms which relies on metal components for its function

Etymology: "Metalloenzyme" is a compound built from two parts: "metallo-", a combining form from Latin "metallum" (itself borrowed from Ancient Greek "métallon", meaning mine or metal), and "enzyme". The enzyme half is the more recent piece: "enzyme" was coined in German by Wilhelm Kühne in 1877 from Greek roots meaning "in leaven" (en zymē), a reference to yeast fermentation, and it was adopted into English shortly afterwards. The metal half reaches English through Latin, where "metallum" referred to a mine and then to the metal extracted from it. Its prefixed form, "metallo-", became a standard scientific combining form in the nineteenth and twentieth centuries, used to join a metal to a named substance or process. Joining the two gives a term for a protein whose catalytic activity depends on a metal ion held in its structure.

Synonyms: metal enzyme, metal-containing enzyme