A Review on β-alanine Biosynthesis

β-alanine is the only non-proteogenic β-amino acid found in nature and is a precursor for important molecules biosynthesis in many organisms. Specifically, it is a precursor for pantothenate in microorganisms, and a component of the dipeptides anserine and carnosine in mammals. Furthermore, β-alanine plays a role in insect exoskeleton formation and is part of plant environmental stress response. Apart from its natural role in organisms, β-alanine has applications in nutrition, pharmaceuticals, chemical synthesis, and construction fields. Due to its health-promoting benefit, β-alanine is increasingly being used by athletes to augment exercise performance and endurance. Moreover, it is a precursor for the synthesis of pamidronate sodium, balsalazide, and other drugs in the pharmaceutical industry. Additionally, β-alanine has been proposed as an intermediate to industrially relevant nitrogen-containing compounds. Traditionally, β-alanine has been produced through harsh chemical synthesis routes which often yield unwanted by-products. Recently, β-alanine production is moving towards relatively environmental- friendly whole-cell biosynthesis providing an attractive alternative that enables enantiomerically pure compound production. Some bio-based methods, however, are limited by enzyme inhibition, low stoichiometric yield, and expensive production cost. Hence, the purpose of this work is to review the recent significant attempts at addressing the limitations of β-alanine production.