E1 mediated ubiquitin activation

Stable Identifier
Reaction [transition]
Homo sapiens
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Ubiquitin is activated in an ATP-dependent manner, catalyzed by E1 ubiquitin-activating enzymes. In the first step of ubiquitin activation, the E1 enzyme binds ATP, Mg+2 and ubiquitin, and catalyses ubiquitin C-terminal acyl-adenylation (Ubiquitin-AMP). In the second step, the catalytic cystine in the E1 attacks the ubiquitin-adenylate (Ub-AMP) to form the activated ubiquitin-E1 thioester-bonded complex and an AMP leaving group. The intermediate reaction involving the formation of the ubiquitin-AMP complex is not represented here.

Literature References
PubMed ID Title Journal Year
19352404 Ubiquitin-like protein activation by E1 enzymes: the apex for downstream signalling pathways

Schulman, BA, Harper, JW

Nat Rev Mol Cell Biol 2009
16595681 Pleiotropic effects of ATP.Mg2+ binding in the catalytic cycle of ubiquitin-activating enzyme

Tokgöz, Z, Bohnsack, RN, Haas, AL

J Biol Chem 2006
18662542 Structural insights into E1-catalyzed ubiquitin activation and transfer to conjugating enzymes

Lee, I, Schindelin, H

Cell 2008
Participant Of
Catalyst Activity
Catalyst Activity
ubiquitin-protein transferase activity of Ubiquitin activating E1 enzymes [cytosol]
Physical Entity
Orthologous Events
Cross References
Target Pathogen
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