Reaction catalyzed by HECT-type E3 ubiquitin transferase (2.3.2.26), RING-type E3 ubiquitin transferase (2.3.2.27), RBR-type E3 ubiquitin transferase (2.3.2.31)

	[E2 ubiquitin-conjugating enzyme]-S-ubiquitinyl-L-cysteine	+		[acceptor protein]-L-lysine	=		[E2 ubiquitin-conjugating enzyme]-L-cysteine	+		[acceptor protein]-N6-ubiquitinyl-L-lysine
	[E2 ubiquitin-conjugating enzyme]-S-ubiquitinyl-L-cysteine	+		[acceptor protein]-L-lysine	=		[E2 ubiquitin-conjugating enzyme]-L-cysteine	+		[acceptor protein]-N6-ubiquitinyl-L-lysine