The multifunctional folic acid synthesis fas gene of Pneumocystis carinii appears to encode dihydropteroate synthase and hydroxymethyldihydropterin pyrophosphokinase.
Volpe F., Dyer M., Scaife JG., Darby G., Stammers DK., Delves CJ.
We describe the cloning of a multifunctional folic acid synthesis (fas) gene from Pneumocystis carinii. The nucleotide sequence contains an open reading frame interrupted by three introns, that encodes a protein of 740 amino acids with an Mr of 97,278. The predicted Fas protein has homology to two enzyme domains, dihydropteroate synthase and 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase, both of which are involved in folate synthesis, and at least one other region of unknown function.