Identification of poly-gamma-glutamyl chain lengths in folates of Bacillus subtilis

Abstract

Bacillus subtilis strains 168 met ile leu and 23 thy contain folates which differ from one another in the number of glutamyl residues. The folate species were identified by reductive cleavage to the corresponding p-aminobenzoylglutamyl poly-gamma-glutamates and chromatography on diethylaminoethyl-cellulose. Pteroyltriglutamate is the predominant folate type, accounting for 86 to 88% of the total. Pteroyltetraglutamate is the only other type present in appreciable quantities, accounting for 5 to 6% of the total folates. Pteroyldiglutamate and pteroylpentaglutamate are present in small amounts, accounting for 1 to 3% and 1% of the total folates, respectively. Strain 168 met ile leu contains a very small amount of pteroylmonoglutamate (less than 0.5% of the total folates), but the other strain contains none.