Morphologically Structured Models

  • Jens Nielsen
  • John Villadsen

Abstract

In Chapters 2 and 4, we specified the stoichiometry and kinetics for the metabolism of individual cells, and it was assumed that all the cells in a culture have the same metabolism; i.e., the cell population was assumed to be completely homogeneous. This assumption is reasonable for most unicellular bacterial cultures (see also the discussion in Chapter 6), but for yeasts and filamentous microorganisms cellular segregation in the culture may have a serious impact on the overall performance of the culture. Thus in yeast cultures there is a difference in the cellular metabolism of mother and daughter cells (see Section 5.2), and in filamentous microorganisms there is a significant variation in the metabolism of the individual cells in the multicellular structures that make up the filaments (see Section 5.3). To describe these cultures correctly it is necessary to consider a morphological variation of the individual cells. Therefore a metabolic model for each individual morphological form is combined with a model for the population of morphological forms, i.e., a morphologically structured model. The theoretical concepts governing the interactions among different morphological forms of the same strain of a given microorganism can also be used to determine the behavior of so-called mixed populations. A mixed cell population could consist of the wild-type strain and several genetically engineered variants of the microorganism, but heterogeneous cultures of very different microorganisms are also included in the discussion of mixed populations in Section 5.4. In the first section of the chapter, a framework for morphologically structured models will be introduced.

Keywords

Specific Growth Rate Dilution Rate Morphological Form Apical Compartment Spontaneous Oscillation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Bailey, J. E. and Ollis, D. F. (1986). Biochemical Engineering Fundamentals, 2d. ed., McGraw-Hill, New York.Google Scholar
  2. Bartnicki-Garcia, S. (1973). “Fundamental aspects of hyphal morphogenesis,” Svmp. Soc. Gen. Microbiol. 23, 245–267.Google Scholar
  3. Bartnicki-Garcia, S. (1990). “Role of vesicles in apical growth and a new mathematical model of hypha morphogenesis,” In Tip Growth in Plant and Fungal Cells, I.B. Heath ed., Academic Press, San Diego.Google Scholar
  4. Caldwell, I. Y. and Trinci, A. P. J. (1973). “The growth unit of the mould Geotrichum candidum, ” Arch. Mikrobiol. 88,1–10.PubMedCrossRefGoogle Scholar
  5. Cazzador, L. (1991). “Analysis of oscillations in yeast continuous cultures by a new simplified model,” Bull. Math. Biol. 5, 685–700.Google Scholar
  6. Cazzador, L. and Mariani, L. (1988). “A simulation program based on a structured population model for biotechnological yeast processes,” Appl. Microbiol. Biotechnol. 29, 198–202.CrossRefGoogle Scholar
  7. Cazzador, L. and Mariani, L. (1990). “A two compartment model for the analysis cf spontaneous oscillations in s. cerevisiae, ” Abstract book (European Congress on Biotechnology, Copenhagen) 5, 342.Google Scholar
  8. Cazzador, L., Mariani, L., Martegani, E., and Alberghina, L. (1990). “Structured segregated models and analysis of self-oscillating yeast continuous culture,” Bioproc. Eng. 5, 175–180.CrossRefGoogle Scholar
  9. Fiddy, C. and Trinci, A. P. J. (1976). “Mitosis, septation, branching and the duplication cycle in Asper-gillus nidulans, ” J. Gen. Microbiol. 97, 169–184.PubMedGoogle Scholar
  10. Frandsen, S. (1993). Dynamics of Saccharomyces Cerevisiae in Continuous culture, Ph.D. thesis, Technical University of Denmark, Lyngby.Google Scholar
  11. Hjortso, M. A. and Nielsen, J. (1994). “A conceptual model of autonomous oscillations in microbial cultures,” Chem. Eng. Sci. 49, 1083–1095.CrossRefGoogle Scholar
  12. Martegani, E., Porro, D., Ranzi, B. M. and Alberghina, L. (1990). “Involvement of a cell size control mechanism in the induction and maintenance of oscillations in continuous cultures of budding yeast,” Biotechnol. Bioneg. 36, 453–459.CrossRefGoogle Scholar
  13. Matsumura, M., Imanaka, T., Yoshida, T., and Tagushi, H. (1981). “Modelling of Cephalosporin C production and application to fed-batch culture,” J. Ferment. Technol. 59, 115–123.Google Scholar
  14. Megee, R. D., Kinishita, S., Fredrickson, A. G., and Tsuchiya, H. M. (1970). “Differentiation and product formation in molds,” Biotechnol. Bioeng. 12, 771–801.PubMedCrossRefGoogle Scholar
  15. Metz, B. and Kossen, N. W. F. (1977). “The growth of molds in the form of pellets-a literature review,” Biotechnol. Bioeng. 19, 781–799.CrossRefGoogle Scholar
  16. Munch, T. (1992). Zellzyklusdynamik von Saccharomyces Cerevisiae in Bioprozessen, Ph.D. thesis, ETH, Zürich.Google Scholar
  17. Nestaas, E. and Wang, D. I. C. (1983). “Computer control of the penicillin fermentation using the filtration probe in conjugation with a structured process model,” Biotechnol. Bioeng. 25,781–796.PubMedCrossRefGoogle Scholar
  18. Nielsen, J. (1992). “Modelling the growth of filamentous fungi,” Adv. Biochem. Eng. Biotechnol. 46, 187–223.PubMedGoogle Scholar
  19. Nielsen, J. (1993). “A simple morphologically structured model describing the growth of filamentous microorganisms,” Biotechnol. Bioeng. 41, 715–727.PubMedCrossRefGoogle Scholar
  20. Nielsen, J. and Villadsen, J. (1992). “Modelling of microbial kinetics,” Chem. Eng. Sci. 47, 4225–4270.CrossRefGoogle Scholar
  21. Packer, H. L., Keshavarz-Moore, E., Lilly, M. D., and Thomas. C. R. (1992). “Estimation of cell volume and biomass of Penicillium chrysogenum using image analysis,” Biotechnol. Bioeng. 39, 384–391.PubMedCrossRefGoogle Scholar
  22. Porro, D., Martegani, E., Ranzi, B. M., and Alberghina, L. (1988). “Oscillations in continuous cultures of budding yeast: A segregated parameter analysis,” Biotechnol. Bioeng. 32, 411–417.PubMedCrossRefGoogle Scholar
  23. Prosser, J. I. and Tough, A. J. (1991). “Growth mechanisms and growth kinetics of filamentous micro-organisms,” Crit. Rev. Biotechnol. 10, 253–274.PubMedCrossRefGoogle Scholar
  24. Riesenberg, D. and Bergter, F. (1979). “Dependence of macromolecular composition and morphology of Streptomyces hygroscopicus on specific growth rate,” Z. Allgemeine Mikrobiol. 19, 415–430.CrossRefGoogle Scholar
  25. Robinson, P. M. and Smith, J. M. (1979). “Development of cells and hyphae of Geotrichum candidum in chemostat and batch culture,” Proc. Br. Mycol. Soc. 72, 39–47.CrossRefGoogle Scholar
  26. Sonnleitner, B. and Käppeli, O. (1986). “Growth of Saccharomyces Cerevisiae is controlled by its limited respiratory capacity: Formulation and verification of a hypothesis,” Biotechnol. Bioeng. 28, 927–937.PubMedCrossRefGoogle Scholar
  27. Strässle, C., Sonnleitner, B., and Fiechter, A. (1988). “A predictive model for the spontaneous synchronization of Saccharomyces Cerevisiae grown in continuous culture I. Concept,” J. Biotechnol. 7, 299–318.CrossRefGoogle Scholar
  28. Strässle, C., Sonnleitner, B., and Fiechter, A. (1989). “A predictive model for the spontaneous synchronization of Saccharomyces Cerevisiae grown in continuous culture II. Experimental verification,” J. Biotechnol. 9, 191–208.CrossRefGoogle Scholar
  29. Trinci, A. P. J. (1974). “A study of the kinetics of hyphal extension and branch initiation of fungal mycelia,” J. Gen. Microbiol. 81, 225–236.PubMedGoogle Scholar
  30. Trinci, A. P. J. (1984). “Regulation of hyphal branching and hyphal orientation,” in The Ecology and Physiology of the Fungal Mycelium, D. H. Jennings and A. D. M. Rayner, eds., Cambridge University Press, Cambridge, UK.Google Scholar
  31. Yang, H., King, R., Reichl, U., and Gilles, E. D. (1992a). “Measurement and simulation of the morpho-logical development of filamentous microorganisms,” Biotechnol. Bioeng. 39, 44–48.PubMedCrossRefGoogle Scholar
  32. Yang, H., King, R., Reichl, U., and Gilles, E. D. (1992b). “Mathematical model for apical growth, septation, and branching of mycelial microorganisms,” Biotechnol. Bioeng. 39, 49–58.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • Jens Nielsen
    • 1
  • John Villadsen
    • 1
  1. 1.Technical University of DenmarkLyngbyDenmark

Personalised recommendations