Abstract
When Leuconostoc mesenteroides NCDO 523 was grown in MRS browth, electron microscopy of cells fixed in the presence of ruthenium red showed that the cell wall was covered with a thin layer of filamentous material. When MRS-grown cells were resuspended in the same medium supplemented with 3.6% sucrose, this surface coat doubled in thickness and a number of radial thickenings appeared within it. After 3 h the filamentous component of the surface coat had disappeared leaving only the radial projections. The progressive accumulation of polymer to produce a capsule visible by light microscopy was observed in only about 20% of the population. In this minority of cells, a dense globular dextran composed of fibrillar and particulate elements was always produced in the initial stages of synthesis. After 18 h, the dextran capsule was generally composed of an inner globular and outer fibrillar layer. It appeared that the outer layer was derived from the globular dextran of the capsule by a process of dispersion.
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Baird, J. K., Longyear, V. M. C., Ellwood, D. C.: Water insoluble and soluble glucans produced by extracellular glycosyltransferases from Streptococcus mutants. Microbios 8, 143–150 (1973)
Craig, A. S.: Sodium borohydride as an aldehyde blocking reagent for electron microscope histochemistry. Histochemistry 42, 141–144 (1974)
Ebert, K. H., Schenk, G.: Mechanisms of biopolymer growth: The formation of dextran and levan. Advanc. Enzymol. 30, 179–221 (1968)
Guggenheim, B., Schroeder, H. E.: Biochemical and morphological aspects of extracellular polysaccharides produced by cariogenic streptococci. Helv. odont. Acta 11, 131–152 (1967)
Jeanes, A., Haynes, W. C., Wilham, C. A., Rankin, J. C., Melvin, E. H., Austin, M. J., Cluskey, J. E., Fisher, B. E., Tsuchiya, H. M., Rist, C. E.: Characterization and classification of dextrans from ninety-six strains of bacteria. J. Amer. chem. Soc. 76, 5041–5052 (1954)
Jeanes, A., Wilham, C. A.: Dextran triacetates. J. Amer. chem. Soc. 74, 5339–5341 (1952)
Lohmar, R.: Evidence of new linkages in dextrans. J. Amer. chem. Soc. 74, 4974 (1952)
Luft, J. H.: Ruthenium red and violet. II. Fine structural localization in animal tissues. Anat. Rec. 171, 369–415 (1971)
de Man, J. C., Rogosa, M., Sharpe, M. E.: A medium for the cultivation of lactobacilli. J. appl. Bact. 23, 130–135 (1960)
McCabe, M. M., Smith, E. E.: Origin of the cell-associated dextransucrase of Streptococcus mutants. Infect. Immun. 7, 829–838 (1973)
Muller, L. L., Jacks, T. J.: Rapid chemical dehydration of samples for electron microscopic examinations. J. Histochem. Cytochem. 23, 107–110 (1975)
Nalbandian, J., Freedman, M. L., Tanzer, J. M., Lovelace, S. M.: Ultrastructure of mutants of Streptococcus mutans with reference to agglutination, adhesion and extracellular polysaccharide. Infect. Immun. 10, 1170–1179 (1974)
Neely, W. B.: Dextran: Structure and synthesis. Advanc. Carbohydr. Chem. 15, 341–369 (1960)
Neely, W. B., Nott, J.: Dextransucrase, an induced enzyme from Leuconostoc mesenteroides. Biochemistry 1, 1136–1140 (1962)
Sidebotham, R. L.: Dextrans. Advanc. Carbohydr. Chem. 30, 371–444 (1974)
Smith, E. E.: Biosynthetic relation between the soluble and insoluble dextrans produced by Leuconostoc mesenteroides NRRL B-1299. FEBS Lett 12, 33–37 (1970)
Thiéry, J. P.: Mise en évidence des polysaccharides sur coupes fincs en microscopie électronique. J. Microsc. (Paris) 6, 987–1018 (1967)
Wilham C. A., Alexander, B. H., Jeanes, A.: Heterogeneity in dextran preparations. Arch. Biochem. 59, 61–75 (1955)
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Brooker, B.E. Surface coat transformation and capsule formation by Leuconostoc mesenteroides NCDO 523 in the presence of sucrose. Arch. Microbiol. 111, 99–104 (1976). https://doi.org/10.1007/BF00446555
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DOI: https://doi.org/10.1007/BF00446555