Reaction catalyzed by E1 ubiquitin-activating enzyme (6.2.1.45)
ATP
+
+
[ubiquitin-activating protein UBE1]-L-cysteine
=
AMP
+
+
[ubiquitin-activating protein UBE1]-S-ubiquitinyl-L-cysteine
ATP
+
ubiquitin
+
[ubiquitin-activating protein UBE1]-L-cysteine
=
AMP
+
diphosphate
+
[ubiquitin-activating protein UBE1]-S-ubiquitinyl-L-cysteine
