Reaction catalyzed by RING-type E3 ubiquitin transferase (2.3.2.27)

	[E2 ubiquitin-conjugating enzyme Ube2B]-S-ubiquitinyl-L-cysteine	+		[acceptor protein]-L-lysine	=		[E2 ubiquitin-conjugating enzyme Ube2B]-L-cysteine	+		[acceptor protein]-N6-ubiquitinyl-L-lysine
	[E2 ubiquitin-conjugating enzyme Ube2B]-S-ubiquitinyl-L-cysteine	+		[acceptor protein]-L-lysine	=		[E2 ubiquitin-conjugating enzyme Ube2B]-L-cysteine	+		[acceptor protein]-N6-ubiquitinyl-L-lysine