Recent Advances in Beta-Alanine Production via Enzymatic Catalysis and Microbial Whole-Cell Catalysis.

Beta-alanine, a naturally occurring non-proteinogenic beta-amino acid, is widely used in delaying fatigue, enhancing exercise performance, and alleviating hyperuricemia. It also serves as a three-carbon platform for the synthesis of various high-value compounds, thus showing extremely broad market prospects. However, the practical application of beta-alanine is severely limited by the harsh reaction conditions and abundant by-products in chemical synthesis, as well as the low endogenous content and complex biosynthetic pathway. Recently, advances have been made in the one-pot, one- or two-step production of beta-alanine using genetically engineered recombinant enzymes, and in the microbial synthesis of beta-alanine via whole-cell biocatalysis. These advances are based on a series of attempts, including the enzymatic conversion to beta-alanine using 1,3-diaminopropane (DAP), L-aspartate (L-Asp), fumarate, or 3-aminopropionitrile as substrates, and the whole-cell biosynthesis of beta-alanine by regulating metabolic flux from carbon sources (e.g., glucose, oil, and glycerol) to L-Asp-the precursor for beta-alanine synthesis catalyzed by L-aspartate-α-decarboxylase (ADC). This study provides a rational theoretical basis and valuable practical references for the future industrial application of beta-alanine.