The Identification of Hexa-, Hepta- and Octoglutamates as the Polyglutamyl Forms of Folate Found throughout the Growth Cycle of Yeast

Abstract

Four p-aminobenzoate (p-AB)-requiring strains of Saccharomyces cerevisiae were studied. All strains grew vigorously on a completely defined medium only when supplemented with 0.025% yeast extract. Strains transferred to fresh media with 14C p-AB removed 80% of the label in 18 h. Most of the label was recovered as heptaglutamate with the remainder in hexa- and octofolate polyglutamates. DEAE-cellulose chromatography was used to separate the components.