Structure of intracellular teichoic acids from group D streptococci

Abstract

Intracellular glycerol teichoic acids (group D antigens) were isolated from the cell contents of two streptococcal strains (39 and 8191). They formed complexes with the RNA of the cell and could be sedimented in the ribosomal fraction. A preparation of purified ribo-somes from group A Streptococcus contained teichoic acid. The compounds from both strains were glycerol phosphate polymers in which all or nearly all glycerol units possessed sugar substituents. D-Alanine ester residues were attached to sugar in both compounds, and that from strain 8191 also possessed a small number of L-lysine ester residues. The compound from strain 39 had kojibiose [[alpha]a-D-glucose -(1[forward arrow]2)-D-glu-cose] attached to glycerol, whereas kojitriose occurred in that from strain 8191. Structures (I) and (n) are proposed for the teichoic acids from strain 39 and 8191 respectively; the latter is composed of about 20 glycosylglycerol phosphate units. The possible location of the amino acid ester residues is discussed. It is concluded that differences in the serological properties of these 2 antigens are associated with the chemical differences in their sugar substituents.