Ubiquitin-protein ligase

In enzymology, an ubiquitin-protein ligase is an enzyme that catalyzes the chemical reaction


 * ATP + ubiquitin + protein lysine $$\rightleftharpoons$$ AMP + diphosphate + protein N-ubiquityllysine

The 3 substrates of this enzyme are ATP, ubiquitin, and protein lysine, whereas its 3 products are AMP, diphosphate, and protein N-ubiquityllysine.

This enzyme belongs to the family of ligases, specifically those forming carbon-nitrogen bonds as acid-D-amino-acid ligases (peptide synthases). The systematic name of this enzyme class is ubiquitin:protein-lysine N-ligase (AMP-forming). This enzyme is also called ubiquitin-activating enzyme. This enzyme participates in 3 metabolic pathways: ubiquitin mediated proteolysis, parkinson's disease, and huntington's disease.

Structural studies
As of late 2007, 75 structures have been solved for this class of enzymes, with PDB accession codes, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , and.