ADP-ribose diphosphatases catalyze the hydrolysis of ADP-ribose (adenosine 5'-diphosphoribose, ADPR) to ribose-5-phosphate and AMP. ADPR is produced enzymatically as part of the turnover of NAD+, cyclic ADPR and poly ADPR. High intracellular levels of ADPR can result in non-enzymatic ADP-ribosylation of proteins, a deleterious process that inactivates enzymes and interferes with recognition processes that rely on enzymatic ADP-ribosylation. Thus, ADP-ribose diphosphatases play an important role in controlling ADPR levels and regulating nucleotide metabolism. (Adapted from
PMID:11323725.)
