Structure of intracellular teichoic acids from group D streptococci

Although considerable attention has been given to the isolation and structure of glycerol teichoic acid and ribitol teichoic acid from bacterial walls (for review see Baddiley, 1962), those that occur in underlying regions of the cell appear to be much more widespread (Armstrong, Baddiley, Buchanan, Carss & Greenberg, 1958; Baddiley & Davison, 1961; A. L. Davison, unpublished work).They have been described for convenience as 'intracellular' teichoic acids, but in the two cases so far studied it is shown that they are probably located in the region between the wall and the protoplast membrane (Hay, Wicken & Baddiley, 1963).They are glycerol phosphate polymers, usually bearing sugar residues, and D-alanine ester groups are always present.Despite the relatively small amounts found in bacteria, and the considerable difficulties encountered during their isolation and purification, structures have been proposed for two found in lactobacilli (Kelemen & Baddiley, 1961; Critchley, Archibald & Baddiley, 1962).The detailed chemical structure of teichoic acids is of particular interest because of their serological reactions (Baddiley & Davison, 1961; Haukenes, Ellwood, Baddiley & Oeding, 1961; Sanderson, Juergens & Strominger, 1961).In streptococci the group D antigen has been identified as the intra- cellular teichoic acid by Wicken, Elliott & Baddiley (1963), who suggested that differences in the serological behaviour of group D antigens from different strains of organism might be a consequence of dif- ferences in their chemical composition.Particular attention was given to Streptococcus faecaUt8 strain 39 and a Streptococcus strain 8191 (N.C.I.B.) which is intermediate in character between S. faecium and S. durans; both organisms are in serological group D and the intracellular teichoic acids are glycerol phosphate polymers containing glucose.The present work shows that the intracellular teichoic acid from strain 39 is a glycerol phosphate polymer with kojibiose [oc-D-glucopyranosyl-(1-+2)-O-D-glucose] in a-glycosidic linkage to glycerol, whereas that from strain 8191 has kojitriose [OC-Dglucopyranosyl-(1-+2)-O-xc-D-glucopyranosyl-(1-+2)-O-D-glucose] in a-glycosidic linkage to glycerol.