Pantoate-beta-alanine ligase, also known as panthotenate synthetase, catalyzes the formation of (R)-pantothenate from pantoate and beta-alanine which is the last step of pantothenate biosynthesis. The reaction is Mg2+-dependent.
Pantothenate (vitamin B5) is a key precursor of the 4-phosphopantetheine moiety of coenzyme A (CoA) and the acyl carrier protein (ACP) which are essential for cell growth. Microorganisms and plants synthesize pantothenate, while animals obtain this nutrient from their diet. The pantothenate-biosynthetic pathway offers a potential target for the design of new drugs against microbial pathogens.