2.4.2.19 nicotinate-nucleotide diphosphorylase (carboxylating); quinolinate phosphoribosyltransferase (decarboxylating); quinolinic acid phosphoribosyltransferase; QAPRTase; NAD+ pyrophosphorylase; nicotinate mononucleotide pyrophosphorylase (carboxylating); • • •