Recycling of bacterial NAD catabolism products.

<p>Reactions described in this study, numbered from 1 to 3, are catalyzed by: 1) NMN deamidase (PncC); 2) NMN adenylyltransferase of the NadM family; 3) ADPR pyrophosphatase. In several bacterial species PncC and NadM occur in fused forms with COG1058 ADPRP and Nudix ADPRP, respectively, as discussed in this work. Abbreviations: Nm, nicotinamide; NMN, nicotinamide mononucleotide; NaMN, nicotinate mononucleotide; NaAD, nicotinate adenine dinucleotide.