kinase
Noun: An enzyme that catalyzes the transfer of a phosphate group from a high-energy donor molecule (such as ATP) to a specific substrate. This process, called phosphorylation, is a fundamental mechanism for regulating the activity of proteins and other molecules within a cell.
Kinases are critical for controlling cellular processes. They are often described in the context of the molecule they modify. * Tyrosine kinase is an important target for some cancer drugs. * The researcher studied the kinase responsible for activating the metabolic enzyme. * Phosphorylation by a specific kinase can turn a protein on or off.
- Kinase cascade / signaling pathway: A series of sequential kinase reactions where one activated kinase phosphorylates and activates the next kinase in the pathway, amplifying a cellular signal.
- The MAP kinase cascade is essential for transmitting growth signals to the nucleus.
- Kinase inhibitor: A type of drug or molecule that blocks the activity of a specific kinase, often used in targeted cancer therapies.
- The patient was treated with a novel kinase inhibitor.
- Phosphokinase: A less common synonym for kinase.
- Protein kinase: A specific and major class of kinases that phosphorylate proteins.
- Phosphatase: An enzyme that performs the reverse reaction of a kinase; it removes a phosphate group from a molecule (dephosphorylation).
- Phosphotransferase
The provided reference context ("an enzyme that catalyzes the conversion of a proenzyme to an active enzyme") describes a specific and narrower function of some kinases. The primary and broader definition in biochemistry is an enzyme that catalyzes phosphorylation—the transfer of a phosphate group. The activation of a proenzyme (or zymogen) is one possible consequence of phosphorylation catalyzed by a kinase.
- an enzyme that catalyzes the conversion of a proenzyme to an active enzyme