proenzyme

noun

The inactive or nearly inactive precursor of an enzyme, converted into an active enzyme by proteolysis.

noun

Any one of a class of proteins that are converted, in the normal course of cellular metabolism, into one or more active enzymes; also called zymogen. The conversion usually is due to a specific cleavage of a peptide bond by another enzyme, or may be due to acid.

noun

Any inactive precursor of an enzyme that is converted to an enzyme by proteolysis; a zymogen

noun

any of a group of compounds that are inactive precursors of enzymes and require some change (such as the hydrolysis of a fragment that masks an active enzyme) to become active