Reaction catalyzed by adenylate dimethylallyltransferase (2.5.1.27)

		+		AMP	=			+
	1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate	+		AMP	=		diphosphate	+		N6-(4-hydroxy-3-methyl-2-(E)-butyl)adenosine 5'-phosphate