Metabolic Engineering of Microbial Chassis Cells for d-Pantothenate Production: A Review.

d-Pantothenate (DPA), an essential functional compound, has experienced increasing market demand due to its widespread applications across the pharmaceutical, cosmetic, and animal feed industries. While numerous microbial classic strains have been engineered for DPA synthesis via microbial fermentation as an alternative to conventional chemoenzymatic synthesis, a comprehensive analysis of the metabolic engineering strategies employed for these microbial chassis cells for DPA production remains absent. This review systematically delineates the DPA metabolic pathway, encompassing β-alanine and pantoate metabolic modules, the regulatory network, and transport systems, and highlights the main regulatory mechanisms of operons and genes involved in the DPA biosynthesis pathway. The current research status in metabolic engineering strategies for manipulating DPA-producing strains is summarized and analyzed to elucidate the current trends and insights for further engineering. Finally, current challenges and future perspectives for the sustainable production of DPA are discussed, and guidelines for reducing production costs are proposed.