Studies on the Group F Antigen of Lactobacilli: Antigenicity and Serological Specificity of Teichoic Acid Preparations Knox, K. W. and Hewett, Merilyn J. and Wicken, A. J.,, 60, 303-313 (1970), doi = https://doi.org/10.1099/00221287-60-3-303, publicationName = Microbiology Society, issn = 1350-0872, abstract= SUMMARY: The membrane glycerol teichoic acid of group F lactobacilli (e.g. Lactobacillus fermenti) has been identified as the group antigen. The most active preparations, obtained by phenol extraction, reacted readily with antisera and were antigenic when injected into rabbits with Freund's adjuvant. The products obtained by the action of trichloracetic acid were separable into a high molecular weight fraction, which reacted well with antiserum but was not a very effective antigen, and a low molecular weight fraction which was not antigenic and reacted weakly with group antisera. Specificity of the group antigen depends primarily on galactose with glucose being a minor contributor. However, the ability of galactose and glucose to inhibit the precipitin reaction differs considerably with different antisera. Teichoic acids from other strains of L. fermenti cross-reacted with the group antisera to varying extents but preparations from L. casei strains reacted only weakly., language=, type=