Ubiquitin Protein Ligase

**Semantic type:** Amino Acid, Peptide, or Protein|Enzyme

**Definition:** Ubiquitin protein ligase enzymes catalyze the formation of a covalent peptide bond between the carboxy-terminal glycine of ubiquitin proteins and lysine alpha-amino group of other proteins. This typically marks proteins for either nonlysosomal proteasomal degradation or targeted transport. Ubiquitination requires sequential action of an activating enzyme, a conjugating enzyme, and a ligase.

**Synonyms:** - Ubiquitin Protein Ligase Complex