Nicotinate phosphoribosyltransferase

In enzymology, a nicotinate phosphoribosyltransferase is an enzyme that catalyzes the chemical reaction


 * nicotinate D-ribonucleotide + diphosphate $$\rightleftharpoons$$ nicotinate + 5-phospho-alpha-D-ribose 1-diphosphate

Thus, the two substrates of this enzyme are nicotinate D-ribonucleotide and diphosphate, whereas its two products are nicotinate and 5-phospho-alpha-D-ribose 1-diphosphate.

This enzyme belongs to the family of glycosyltransferases, specifically the pentosyltransferases. The systematic name of this enzyme class is nicotinate-nucleotide:diphosphate phospho-alpha-D-ribosyltransferase. Other names in common use include niacin ribonucleotidase, nicotinic acid mononucleotide glycohydrolase, nicotinic acid mononucleotide pyrophosphorylase, and nicotinic acid phosphoribosyltransferase. This enzyme participates in nicotinate and nicotinamide metabolism.

Structural studies
As of late 2007, 7 structures have been solved for this class of enzymes, with PDB accession codes, , , , , , and.