1,3-propanediol

1,3-Propanediol is a versatile three-carbon diol that is widely used as an industrial chemical and serves as a building block for the production of materials such as adhesives, coatings, and antifreeze [363].

Although native microbial production of 1,3-propanediol commonly relies on glycerol as a carbon substrate, metabolic engineering has enabled its de novo biosynthesis from glucose. One strategy involved integrating a heterologous glycerol biosynthesis pathway from Saccharomyces cerevisiae with the glycerol-to-1,3-propanediol pathway from Klebsiella pneumoniae, thereby enabling 1,3-propanediol production from glucose. In addition, a non-natural pathway for the conversion of L-homoserine to 1,3-propanediol has been developed through the coordinated optimization of aspartate transaminase (AspC from Escherichia coli), pyruvate decarboxylase (Pdc from Zymomonas mobilis), and alcohol dehydrogenase (YqhD from E. coli) [363].