Description: Catalyzes the condensation of nicotinamide with 5-phosphoribosyl-1-pyrophosphate to yield nicotinamide mononucleotide, an intermediate in the biosynthesis of NAD. It is the rate limiting component in the mammalian NAD biosynthesis pathway. (www.uniprot.org) Produced in E.coli as a single, non-glycosylated, polypeptide chain containing His tag and having 511 amino acids.