Catalyzes the condensation of iminoaspartate with dihydroxyacetone phosphate to form quinolinate. dihydroxyacetone phosphate + iminosuccinate = H(+) + 2 H2O + phosphate + quinolinate Binds 1 [4Fe-4S] cluster per subunit. Cofactor biosynthesis; NAD(+) biosynthesis; quinolinate from iminoaspartate: step 1/1. Was identified as a high-confidence drug target. Belongs to the quinolinate synthase family. Type 2 subfamily.