Enzymes that Transfer the ADP-Ribose group of NAD or NADP to Proteins or other small molecules. Transfer of ADP-Ribose to Water (i.e., Hydrolysis) is catalyzed by the NADases. The mono(ADP-Ribose)Transferases Transfer a single ADP-Ribose. Poly(ADP-ribose) Polymerases Transfer multiple units of ADP-Ribose to protein targets, building Poly Adenosine Diphosphate Ribose in linear or branched chains.