processive

Processive is an adjective used mainly in biology and linguistics to describe a property of systems that can carry out multiple catalytic or semantic steps without releasing the substrate or resetting.

In biochemistry and molecular biology, a processive enzyme or motor performs successive catalytic cycles while bound to its substrate. For nucleic acid polymerases, processivity is the average number of nucleotides added per binding event, with higher processivity allowing long stretches of DNA or RNA to be synthesized before the enzyme dissociates. Processivity is often enhanced by structural features that hold the substrate in the active site or by accessory elements such as sliding clamps in DNA replication, which encircle the nucleic acid and retain the polymerase on the template. Processive enzymes contribute to the efficiency and speed of cellular processes like DNA replication and transcription, while non-processive enzymes must repeatedly rebind to continue catalysis, reducing throughput.

In motor proteins, processivity refers to the ability of a molecular motor to take multiple steps along a track, such as microtubules or actin filaments, before detaching. Highly processive motors can move long distances without dissociating, whereas less processive motors frequently detach, affecting intracellular transport efficiency.

In linguistics, processivity describes how a verb treats the action as a continuous process that affects a direct object, influencing event structure and interpretation. Processive and non-processive classifications help describe cross-linguistic verb behavior and syntax.

See also: sliding clamp, motor protein, enzyme processivity.