Polysaccharides of marine diatoms with special reference to Chaetoceros species
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The alkali-soluble polysaccharides of the cell wall from 7 different marine diatoms were shown to contain the monosaccharides rhamnose, fucose, galactose, mannose and xylose. The relative amounts of rhamnose and fucose varied widely from one species to another, from the very rhamnose-rich Chaetoceros affinis to Thalassiosira gravida, where no rhamnose was found. All Chaetoceros species were found to have a high content of rhamnose. Also the proportion of mannose to galactose varied widely from species to species. The observed change in monomer composition from the logarithmic to the stationary growth phase is explained by assuming the alkali-soluble fraction to be a mixture of polysaccharides. The soluble, extracellular polysaccharides from 4 of the diatoms were also investigated. The products from C. affinis and C. curvisetus were homogeneous and composed of only 3 monomers: rhamnose, fucose and galactose. The extracellular polysaccharide composition in all species investigated was quite different from the composition of the cellular alkali-soluble fraction. The ecological aspects of these soluble polysaccharides may prove of considerable interest.
KeywordsPolysaccharide Xylose Galactose Growth Phase Mannose
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- Allan, G.G., J. Lewin and P.G. Johnson: Marine polymers. IV. Diatom polysaccharides. Botanica mar. 15, 102–108 (1972)Google Scholar
- Coombs, J. and B.E. Volcani: Studies on the biochemistry and fine structure of silica shell formation in diatoms. Silicon-induced metabolic transients in Navicula pelliculosa (Breb.) Hilse. Planta 80, 264–279 (1968a)Google Scholar
- —: Studies on the biochemistry and fine structure of silica shell formation in diatoms. Chemical changes in the wall of Navicula pelliculosa during its formation. Planta 82, 280–292 (1968b)Google Scholar
- Ford, C.W. and E.E. Percival: Carbohydrates of Phaeodactylum tricornutum. J. chem. Soc. 7042–7046 (1965)Google Scholar
- Hecky, R.E., K. Mopper, P. Kilham and E.T. Degens: The amino acid and sugar composition of diatom cell-walls. Mar. Biol. 19, 323–331 (1973)Google Scholar
- Medcalf, D.G., J.H. Brannon, J.R. Scott, J. Lewin, G.G. Allan and G.E. Norris: Polysaccharides from microscopic red algae and diatoms. Proc. int. Seaweed Symp. (8, Bangor 1974). (In press)Google Scholar
- — and B.E. Volcani: Studies on the biochemistry and fine structure of silica shell formation in diatoms. III. The structure of the cell wall of Phaeodactylum tricornutum Bohlin. J. Ultrastruct. Res. 21, 182–193 (1968)Google Scholar
- Smestad, B., A. Haug and S. Myklestad: Production of carbohydrate by the marine diatom Chaetoceros affinis var. willei (Gran) Hustedt. III. Structural studies of the extracellular polysaccharide. Acta chem. scand. (B) 28 662–666 (1974)Google Scholar
- ——: Structural studies of the extracellular polysaccharide produced by the diatom Chaetoceros curvisetus Cleve. Acta chem. scand. (B) 29, 337–340 (1975)Google Scholar