A molecule that increases the activity of the enzyme (EN). The activation effect can be characterized by activation degree (AD), maximum activation degree (MAD), activation constant (KA) or half-activating concentration (A05), activation type (ACT) and type of kinetics (KT).
Unlike an absolutely required agent (AR), activators demonstrate limited activation degree.
It is arbitrarily prssumed that the degree of activation (AD) must be more than or equal to 3% of the original activity, in order for the process to be considered activating.