It is the goal of this project to determine the structure and microdynamic behavior of antigenic bacterial cell wall polysaccharides, primarily through the application of carbon-13 NMR spectroscopy. Under current investigation are: 1) N. Meningitidis serogroups B and C capsular polysaccharides and the immunologically cross-reactive (to serogroup C) E. Coli strains, Bos-12, MT-411, and NT 67; 2) H. Influenza type b, polysaccharides and their immunologically cross-reactive E. Coli strains, Easter and 89; 3) The Pneumococcus C polysaccharides; 4) "pathogenic" E. coli strains.