InterPro domain: IPR041525

Nicotinate phosphoribosyltransferase ( 2.4.2.11 ) is the rate-limiting enzyme that catalyses the first reaction in the NAD salvage synthesis [ 1 ]. Members in this family can be split into two further subfamilies represented in IPR006405 and IPR006406 . Members in IPR006405 have a different (longer) spacing of several key motifs and have an additional C-terminal domain of up to 100 residues. However, one argument suggesting that this family represents the same enzyme is that no species has a member of both subfamilies. Another is that the gene encoding this protein is located near other NAD salvage biosynthesis genes in Nostoc and in at least four different Gram-positive bacteria.

Nicotinamide phosphoribosyl transferase (NAMPT) catalyses the condensation of nicotinamide with 5-phosphoribosyl-1-pyrophosphate to yield nicotinamide mononucleotide, an intermediate in the biosynthesis of NAD [ 2 , 3 ]. NAMPT is also known as pre-B cell colony-enhancing factor (PBEF) or visfatin.

1. Biosynthesis and recycling of nicotinamide cofactors in mycobacterium tuberculosis. An essential role for NAD in nonreplicating bacilli. J. Biol. Chem. 283, 19329-41
2. Nicotinamide phosphoribosyltransferase (Nampt): a link between NAD biology, metabolism, and diseases. Curr. Pharm. Des. 15, 20-8
3. Nampt: linking NAD biology, metabolism and cancer. Trends Endocrinol. Metab. 20, 130-8