The conversion of (R)-pantoate to (R)-4'-phosphopantothenate is part of the pathway leading to biosynthesis of 4'-phosphopantetheine, an essential cofactor of coenzyme A and acyl-carrier protein. In bacteria and eukaryotes this conversion is performed by condensation with beta-alanine, followed by phosphorylation (EC 6.3.2.1 and EC 2.7.1.33, respectively). In archaea the order of these two steps is reversed, and phosphorylation precedes condensation with beta-alanine.
