Cell wall polysaccharides of red algae include the commercially important carrageenans and agarocolloids as well as cellulose, xylans, mannans, and complex heteropolysaccharides. Due in part to the commercial significance of these compounds and their derivatives as gelling, emulsifying, and sizing agents, much is known of the chemistry of these polymers from selected organisms. Relatively little is known, however, about the taxonomic distribution of these and related natural products among major groups of the red algae (Rhodophyta). Drs. Gretz and Sommerfeld are undertaking an extensive chemical survey to address this problem. Cell wall polysaccharides are also potentially useful biochemical markers that may be valuable in the assessment of natural evolutionary affinities between algal groups. Efforts in this project will be directed toward biochemical analysis of cell walls of "key" groups in the Erythropeltidales, Compsopogonales, Rhodochaetales, Achrochaetiales, Nemaliales, Batrachospermales, and Bonnemaisonales using modern techniques such as methylation analysis (gas chromatography/mass spectrometry), nuclear magnetic resonance and x-ray diffraction analysis. In addition to the scientific information generated and the potential for discovery of sources of novel natural products, this project is designed to encourage undergraduate students to participate in original research. Students will be exposed directly to the application of the scientific method and to modern analytical techniques and apparatus, which will stimulate their interest in careers in science.