konvertase

Konvertase, often translated as convertase in English, is a general term for enzymes that catalyze the conversion of a substrate into another molecule, frequently by proteolytic processing that activates a precursor protein. In molecular biology, the term often refers to proprotein konvertases, a family of subtilisin-like serine proteases that activate a wide range of peptide hormones, receptors, and viral glycoproteins by cleaving their inactive precursors at specific sites.

Most well-known are the proprotein konvertases of the PCSK family. They require calcium and function in the secretory pathway, from the endoplasmic reticulum through the Golgi to secretory granules, cleaving substrates at basic residues, commonly at motifs such as R-X-(K/R)-R, to generate mature protein forms.

Key members include furin (PCSK3), PC1/3 (PCSK1), PC2 (PCSK2), PC4, PC5/6, PC7, and PACE4 (PCSK6). Furin processes many substrates, including growth factors and viral envelope proteins; PC1/3 and PC2 activate numerous neuropeptides and hormones; PCSK9 regulates the LDL receptor and cholesterol homeostasis.

Clinical and research relevance: dysregulation of konvertase activity is associated with developmental disorders, cancer progression, and metabolic diseases. Therapeutic approaches target konvertases, such as PCSK9 inhibitors used to lower LDL cholesterol, and experimental furin inhibitors pursued for antiviral and anticancer strategies. Ongoing work covers substrate specificity, tissue expression, and regulation by cofactors and intracellular trafficking.