Gtpase

Part of speech: noun

Definitions

1. An enzyme that binds and hydrolyzes guanosine triphosphate (GTP), involved in signaling and molecular switches in cells
2. A protein that acts as a molecular switch by cycling between active GTP-bound and inactive GDP-bound states to regulate cellular processes
3. A GTP-binding enzyme that controls various biological activities by converting GTP to GDP, thus influencing cell function and communication

Etymology: GTPase is a compound of "GTP," the abbreviation for guanosine triphosphate, the nucleotide that cells use as an energy carrier, and "-ase," the suffix chemists attach to enzyme names. The name was built in the twentieth century, when biochemists were working out how the cell's signalling machinery switches on and off, so no ancient or classical source lies behind it. The "-ase" ending itself was coined in the nineteenth century, by analogy with "diastase," the first enzyme to be isolated, in 1833, from malt. The word describes the job of these enzymes: they split GTP into GDP and inorganic phosphate, releasing energy that drives a switch. Many GTPases act as molecular on-off toggles, flipping between an active state when bound to GTP and an inactive state when bound to GDP. Because so many of them regulate growth, division and transport inside cells, the term became a standard label across molecular biology.

Synonyms: GTP hydrolase, GTPase enzyme, GTPase protein, molecular switch enzyme, GTP-binding enzyme