Poly (3-hydroxypropionate) (P3HP), a new member of thermoplastic of family polyhydroxyalkanoates (PHAs), has excellent characteristics of biodegradability and biocompatibility. By now no reports can be found about wild-type bacteria that naturally synthesize P3HP, so the main way to produce P3HP is chemical and biological methods. Chemical method by adding high cost 3-HP monomers or their structural analogs as precursors, has the drawbacks of toxicity, low effectiveness and high cost. Biological method using engineered strain may utilize inexpensive and renewable carbon source to produce P3HP and has gradually become more and more popular. We systematically review here the biosynthesis of P3HP research progress. The advantages and disadvantages of biosynthesis pathways of glycerol pathway, malonyl-CoA pathway and β-alanine pathway were analyzed.

As an important platform compound, 3-hydroxypropionic acid (3-HP) can be used as a substrate to synthesize a variety of biological products with commercial potential. The titer of 3-HP by wild-type bacteria is low, which severely limits the large-scale application and production of 3-HP. By modifying the genes related to the metabolic pathway, engineered bacteria using cheap substrates as carbon sources are constructed, the aim of reducing production cost and increasing output is realized. In this paper, the recent progress in the synthesis of 3-HP by metabolic engineering at home and abroad is reviewed. The advantages and disadvantages of glycerol pathway, malonyl-CoA pathway and beta-alanine pathway for synthesis of 3-HP are also summarized and analyzed, and the future development of 3-HP is prospected.
Glycerol ; metabolism ; Industrial Microbiology ; trends ; Lactic Acid ; analogs & derivatives ; biosynthesis ; Metabolic Engineering ; Metabolic Networks and Pathways ; genetics