An overview of engineering microbial production of nicotinamide mononucleotide

As the human body gradually ages, the cellular level of NAD⁺ will decline, which has been found to be related to a variety of age-related diseases. As a precursor of NAD⁺, NMN is able to effectively promote the synthesis of NAD⁺ with no significant side effects. Microbial production of NMN holds the potential to lower the production cost and facilitate its wide application. In this review, based on the metabolic pathway of NAD⁺, we summarize recent advances of metabolic engineering strategies for NMN biosynthesis. An outlook for future optimization to improve NMN production is also discussed.