Journal of Applied Phycology

, Volume 8, Issue 4–5, pp 275–281 | Cite as

Response of an exopolysaccharide-producing heterocystous cyanobacterium to changes in metabolic carbon flux

  • Roberto De Philippis
  • Claudio Sili
  • Massimo Vincenzini


The response of the exopolysaccharide-producing heterocystous cyanobacteriumCyanospira capsulata to changes in metabolic carbon flux was investigated to estimate the potential for improvement of the exopolysaccharide (EPS) yield. Carbon flux was altered by transferring the organism either to an argon atmosphere or to medium containing the nitrogen assimilation inhibitors L-methionine-D,L-sulfoximine (MSX), O-diazoacetyl-L-serine (AZAS) or D,L-7-azatryptophan (AZAT), or by adding glyoxylate, known to stimulate carbon metabolism. When carbon flux was modified by interfering with nitrogen metabolism, the concentration of total carbohydrates exceeded that of the control culture only in Ar- or AZAS-treated cell suspensions, but this difference was mainly due to enhancement of the quantity of bound carbohydrates. On the other hand, when carbon flux was modified by a single addition of glyoxylate (30 mM) or by daily additions of 10 mM glyoxylate without interfering with nitrogen metabolism, carbohydrate release into the medium was stimulated markedly; after 5 days of growth in the presence of the organic compound, the concentration of EPS was 43 % higher than in the control culture. The results demonstrate that, with enhanced carbon flux, the excess carbon is preferentially channeled byC. capsulata cells into the synthesis of an overflow product like EPS, whereas, with mere diversion of carbon flux from the process of nitrogen assimilation, the synthesis of carbon reserves is more heavily favoured.

Key words

Cyanobacteria Cyanospira capsulata exopolysaccharide production carbon flux glyoxylate azaserine azatryptophan methionine-sulfoximine 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Arad SM, Friedman OD, Rotem A (1988) Effect of nitrogen on polysaccharide production in aPorphyridium sp. Appl. envir. Microbiol. 54: 2411–2414.Google Scholar
  2. Arad SM, Lerental YB, Dubinsky O (1992) Effect of nitrate and sulfate starvation on polysaccharide formation inRhodella reticulata. Biores. Technol. 42: 141–148.Google Scholar
  3. Bergman B (1980) Stimulation of nitrogenase activity and photosynthesis in some cyanobacteria by glyoxylate. Physiol. Pl. 49: 398–404.Google Scholar
  4. Bergman B (1986) Glyoxylate induced changes in the carbon and nitrogen metabolism of the cyanobacteriumAnabaena cylindrica. Plant. Physiol. 80: 698–701.Google Scholar
  5. Bennet A, Bogorad L (1973) Complementary chromatic adaptation in a filamentous blue-green alga. J. Cell Biol. 58: 419–435.PubMedGoogle Scholar
  6. Cesaro A, Liut G, Bertocchi C, Navarini L, Urbani R (1990) Physicochemical properties of the exocellular polysaccharide fromCyanospira capsulata. Int. J. biol. Macromol. 12: 79–84.PubMedGoogle Scholar
  7. De Philippis R, Sili C, Tassinato G, Vincenzini M, Materassi R (1991) Effects of growth conditions on exopolysaccharide production byCyanospira capsulata. Biores. Technol. 38: 101–104.Google Scholar
  8. De Philippis R, Sili C, Vincenzini M (1992) Glycogen and poly-β-hydroxybutyrate synthesis inSpirulina maxima. J. gen. Microbiol. 138: 1623–1628.Google Scholar
  9. De Philippis R, Margheri MC, Pelosi E, Ventura S (1993) Exopolysaccharide production by a unicellular cyanobacterium isolated from a hypersaline habitat. J. appl. Phycol. 5: 387–394.Google Scholar
  10. Dubois M, Gilles KA, Hamilton JK, Rebers PA, Smith F (1956) Colorimetric method for determination of sugars and related substances. Analyt. Chem. 28: 350–356.Google Scholar
  11. Ernst A, Böger P (1985) Glycogen accumulation and the induction of nitrogenase activity in the heterocyst-forming cyanobacteriumAnabaena variabilis. J. gen. Microbiol. 131: 3147–3153.Google Scholar
  12. Fresnedo O, Serra JL (1992) Effect of nitrogen starvation on the biochemistry ofPhormidium laminosum (Cyanophyceae). J. Phycol. 28: 786–793.Google Scholar
  13. Kroen WK, Rayburn WR (1984) Influence of growth status and nutrients on extracellular polysaccharide synthesis by the soil algaChlamydomonas mexicana (Chlorophyceae). J. Phycol. 20: 253–257.Google Scholar
  14. Lapasin R, Pricl S, Bertocchi C, Navarini L, Cesaro A, De Philippis R (1992) Rheology of culture broths and exopolysaccharide ofCyanospira capsulata at different stages of growth. Carbohydr. Polym. 17: 1–10.Google Scholar
  15. Panoff JM, Priem B, Morvan H, Joset F (1988) Sulphated exopolysaccharides produced by two unicellular strains of cyanobacteria,Synechocystis PCC 6803 and 6714. Arch. Microbiol. 150: 558–563.Google Scholar
  16. Parson TR, Strickland JDH (1963) Discussion of spectrophotometric of marine plant pigments, with revised equations for ascertaining chlorophylls and carotenoids. J. mar. Res. 21: 155–163.Google Scholar
  17. Preiss J, Romeo T (1989) Physiology, biochemistry and genetics of bacterial glycogen synthesis. Adv. microb. Physiol. 30: 183–238.PubMedGoogle Scholar
  18. Ramos JL, Madueno F (1986) Induction of increase in the heterocyst frequency ofAnabaena sp. strain ATCC33047. Effect on ammonium photoproduction. FEMS Microbiol. Lett. 36: 73–76.Google Scholar
  19. Rippka R, Deruelles J, Waterbury JB, Herdman M, Stanier RY (1979) Genetic assignments, strain histories and properties of pure culture of cyanobacteria. J. gen. Microbiol. 111: 1–61.Google Scholar
  20. Rogerson AC (1979) Modifiers of heterocyst repression and spacing and formation of heterocysts without nitrogenase in the cyanobacteriumAnabaena variabilis. J. Bact. 140: 213–219.PubMedGoogle Scholar
  21. Stevens SE, Jr, Balkwill DL, Paone DAM (1981) The effects of nitrogen limitation on the ultrastructure of the cyanobacteriumAgmenellum quadruplicatum. Arch. Microbiol. 130: 204–212.Google Scholar
  22. Sudo H, Burgess JG, Takemasa H, Nakamura N, Matsunaga T (1995) Sulfated exopolysaccharide production by the halophilic cyanobacteriumAphanocapsa halophytia. Curr. Microbiol. 30: 219–222.Google Scholar
  23. Turner GL, Gibson AH (1980) Measurement of nitrogen fixation by indirect means. In Bergerson FI (ed.), Methods for Evaluating Biological Nitrogen Fixation. Wiley & Sons, New York, 111–138.Google Scholar
  24. Van Rijn J, Shilo M (1986) Nitrogen limitation in natural populations of cyanobacteria (Spirulina andOscillatoria spp.) and its effect on macromolecular synthesis. Appl. envir. Microbiol. 52: 340–344.Google Scholar
  25. Vincenzini M, De Philippis R, Ena A, Florenzano G (1986) Ammonia photoproduction byCyanospira rippkae cells ‘entrapped’ in dyalisis tube. Experientia 42: 1040–1043.Google Scholar
  26. Vincenzini M, De Philippis R, Sili C, Materassi R (1990) Studies on exopolysaccharide release by diazotrophic batch cultures ofCyanospira capsulata. Appl. Microbiol. Biotechnol. 34: 392–396.Google Scholar
  27. Vincenzini M, De Philippis R, Sili C, Materassi R (1993) Stability of molecular and rheological properties of the exopolysaccharide produced byCyanospira capsulata cultivated under different growth conditions. J. appl. Phycol. 5: 539–541.Google Scholar
  28. Zarrouk C (1966) Contribution a l'étude d'une cyanophycée. Influence de divers facteurs physique et chimique sur la croissance et la photosynthèse deSpirulina maxima (Sech. et Gardner) Geitler. Ph. D. Thesis. University of Paris, France.Google Scholar

Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • Roberto De Philippis
    • 1
    • 2
  • Claudio Sili
    • 1
    • 2
  • Massimo Vincenzini
    • 1
    • 2
  1. 1.Dipartimento di Scienze e Tecnologie Alimentari e MicrobiologicheUniversità degli StudiFirenzeItaly
  2. 2.Centro di Studio dei Microrganismi Autotrofi, CNRFirenzeItaly

Personalised recommendations