1887

Abstract

Chlorate-resistant, highly branched (colonial) mutants and auxotrophic mutants were used to study the nuclear distribution, morphology and growth of heterokaryons of the Quorn myco-protein fungus, A3/5. The results showed that for several complementary homokaryons, even a strong selective pressure was insufficient to maintain heterokaryons in a ‘balanced’ condition (i.e. exhibiting a wild-type or near wild-type phenotype). Furthermore, the margins of heterokaryotic colonies generally contained nuclei from only one of the parental homokaryons, indicating imperfect nuclear mixing within the mycelium. These observations suggest that recessive, colonial mutants may appear during Quorn myco-protein production following shear-induced separation of hyphal fragments which contain a sufficiently high ratio of colonial : wild-type nuclei for the colonial phenotype to be expressed.

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1996-03-01
2021-04-21
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References

  1. Adams G., Johnson N., Leslie J. F., Hart L. P. 1987; Heterokaryons of Gibberella zeae following hyphal anastomosis or protoplast fusion. Exp Mycol 11:339–353
    [Google Scholar]
  2. Barratt R. W., Garnjobst L. 1949; Genetics of a colonial microconidiating mutant strain of Neurospora crassa . Genetics 34:351–369
    [Google Scholar]
  3. Beadle G. W., Coonradt V. L. 1944; Heterocaryosis in Neurospora crassa . Genetics 29:291–308
    [Google Scholar]
  4. Bowden R. L., Leslie J. F. 1992; Nitrate-nonutilizing mutants of Gibberella zeae (Fusarium graminearum) and their use in determining vegetative compatibility. Exp Mycol 16:308–315
    [Google Scholar]
  5. Correll J. C., Klittich C. J. R., Leslie J. F. 1987; Nitrate nonutilizing mutants of Fusarium oxysporum and their use in vegetative compatibility tests. Phytopathology 77:1640–1646
    [Google Scholar]
  6. Cove D. J. 1976; Chlorate toxicity in Aspergillus nidulans: the selection and characterisation of chlorate resistant mutants. Heredity 36:191–203
    [Google Scholar]
  7. Jinks J. L. 1952; Heterokaryosis: a system of adaptation in wild fungi. Proc Roy Soc B 140:83–99
    [Google Scholar]
  8. Klittich C. J. R., Leslie J. F. 1988; Nitrate reduction mutants of Fusarium moniliforma (Gibberella fujikuroi). Genetica 118:417–423
    [Google Scholar]
  9. Miller J. J. 1946; Cultural and taxonomic studies on certain Fusaria. I. Mutations in culture. Can J Res 24(C):188–212
    [Google Scholar]
  10. Pittenger T. H., Atwood K. C. 1954; The relation of growth rate to nuclear ratio in Neurospora heterokaryons. Genetics 39:987–988
    [Google Scholar]
  11. Puhalla J. E. 1984; A visual indicator of heterokaryosis in Fusarium oxysporum from celery. Can J Bot 62:540–545
    [Google Scholar]
  12. Puhalla J. E., Spieth P. T. 1983; Heterokaryosis in Fusarium moniliforma . Exp Mycol 7:328–335
    [Google Scholar]
  13. Sanchez L. E., Leary J. V., Endo R. M. 1976; Heterokaryosis in Fusarium oxysporum f. sp. lycopersici . J Gen Microbiol 93:219–226
    [Google Scholar]
  14. Toth K. F., Lacy M. L. 1991; Comparing vegetative compatibility and protein banding patterns for identification of Fusarium oxysporum f. sp. apii race 2. Can J Microbiol 37:669–674
    [Google Scholar]
  15. Trinci A. P. J. 1969; A kinetic study of the growth of Aspergillus nidulans and other fungi. J Gen Microbiol 57:11–24
    [Google Scholar]
  16. Trinci A. P. J. 1972; Culture turbidity as a parameter of mould growth. Trans Brit Mycol Soc 58:467–473
    [Google Scholar]
  17. 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
    [Google Scholar]
  18. Trinci A. P. J. 1992; Myco-protein - a twenty-year overnight success story. Mycol Res 96:1–13
    [Google Scholar]
  19. Trinci A. P. J. 1994; Evolution of the Quorn® myco-protein fungus, Fusarium graminearum A3/5. The 1994 Marjory Stephenson Prize Lecture. Microbiology 140:2181–2188
    [Google Scholar]
  20. Vogel H. J. 1956; A convenient growth medium for Neurospora (Medium N). Microb Genet Bull 13:42–44
    [Google Scholar]
  21. Wiebe M. G., Trinci A. P. J. 1991; Dilution rate as a determinant of mycelial morphology in continuous culture. Biotech Bioeng 38:75–81
    [Google Scholar]
  22. Wiebe M. G., Robson G. D., Cunliffe B., Trinci A. P. J., Oliver S. G. 1991; Appearance of morphological (colonial) mutants in glucose-limited, continuous flow cultures of Fusarium graminearum . Mycol Res 95:1284–1288
    [Google Scholar]
  23. Wiebe M. G., Robson G. D., Trinci A. P. J., Oliver S. G. 1992; Characterisation of morphological mutants generated spontaneously in glucose-limited continuous flow cultures of Fusarium graminearum A3/5. Mycol Res 96:555–562
    [Google Scholar]
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