Facilitates the combination of p-aminobenzoate and 2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine diphosphate to form 7,8-dihydropteroate.
Facilitates the conversion of 6-hydroxymethyl-dihydropterin to 2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine diphosphate.