Kinases are turned on or off by phosphorylation (sometimes by the kinase itself - cis-phosphorylation/autophosphorylation), by binding of activator proteins or inhibitor proteins, or small molecules, or by controlling their location in the cell relative to their substrates.
enzyme | Continuous erythropoietin receptor activator | Tissue plasminogen activator | Enzyme inhibition | enzyme inhibition | Restriction enzyme | Enzyme inhibitor | enzyme inhibitor | Enzyme Commission number | Enzyme | Constitutive enzyme | Adaptive enzyme | Tissue Plasminogen Activator | Phospholipase cleavage sites. Note that an enzyme that displays both PLA1 and PLA2 activities is called a ''Phospholipase B | Enzyme Records | Enzyme activator | APC/C activator protein CDH1 |