1887

Abstract

The role of selectable strain variations in the development of pathogen strategies was examined using lines of isolated from homopteran (isolate 549) or coleopteran (isolate 808) hosts. Conidia of strain 549 germinated in either alanine, glucose, cyclic AMP or the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX). The non-metabolizable glucose analogues, 3--methylglucose and 6-deoxyglucose, did not allow germination by themselves but stimulated germination when added to IBMX. By contrast, 2-deoxyglucose (dGlc) blocked germination on glucose or IBMX and inhibited hyphal growth on other carbon sources including alanine and glycerol. Conidia of strain 808 germinated rapidly in alanine but responded slowly to glucose or IBMX in the medium and were resistant to the growth inhibitory effects of dGIc. Radioactive dGIc was taken up by conidia of strains 549 and 808 at similar rates and was recovered mainly as 2-deoxyglucose 6-phosphate. Competition experiments utilizing both strains demonstrated that glucose, dGIc and 3--methylglucose were transported by the same system. Fructose was much less able than glucose to inhibit uptake of dGIc indicating that fructose is taken up by a different transport system than that for glucose. It is unlikely, therefore, that the resistance of strain 808 to dGIc is explained by reduced sugar transport compared with strain 549 but that strains 549 and 808 differ in the regulation of carbon metabolism with some systems in strain 808 showing resistance to the catabolite-repressing effects of glucose. Apparently, catabolite repression is subdivided into different segments as glucose inhibited the derepression of a number of catabolite repressible enzymes in strain 808, including the pathogenicity determinant protease Pr1. The same effect was produced by dGIc but not by 3--methylglucose, indicating that the trigger for catabolite repression occurs at the level of transport-associated glucose phosphorylation. A comparative study of 26 isolates indicated that most lines from coleopteran hosts were dGIc resistant and germinated poorly on glucose. Conversely, isolates germinating well on glucose (mostly from hemipteran and lepidopteran hosts) were dGIc susceptible.

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1994-07-01
2022-01-20
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References

  1. Allen K.E., McNally M.T., Lowendorf H.S., Slayman C.W., Free S.J. Deoxyglucose-resistant mutants of Neurospora crassa isolation, mapping, and biochemical characterization. J Bacteriol 1989; 171:53–58
    [Google Scholar]
  2. Beullens M., Mbonyi K., Geerts L., Gladines D., Detremerie K., Jans A.W.H., Thevelein J.M. Studies on the mechanism of the glucose-induced cAMP signal in glycolysis of glucose repression mutants of the yeast Saccharowyces cerevisiae. Eur J Biochew 1988; 172:227–231
    [Google Scholar]
  3. Bourret J.A. Glucose transport by germinating Pilobolus longipes spores. Exp Mycol 1985; 9:48–55
    [Google Scholar]
  4. Bourret J.A. The mechanism by which 2-deoxyglucose inhibits glucose-induced activation of Pilobolus longipes spores. Exp Mycol 1987; 11:307–316
    [Google Scholar]
  5. Dillon R.J., Charnley A.K. Initiation of germination in conidia of the entomopathogenic fungus, Metarhitfuw anisopliae. Mycol Res 1990; 94:299–304
    [Google Scholar]
  6. Eraso P., Gancedo J.M. Use of glucose analogues to study the mechanism of glucose-mediated cAMP increase in yeast. FEBS Lett 1985; 191:51–54
    [Google Scholar]
  7. Gancedo J.M. Carbon catabolite repression in yeast. Eur J Biochew 1992; 206:297–313
    [Google Scholar]
  8. Johnson M., Carlson M. Regulation of carbon and phosphate utilization. In The Molecular and Cellular Biology of the Yeast Saccharowyces 1992 Cold Spring Harbor Laboratory: Cold Spring Harbor Laboratory Press; pp 193–282
    [Google Scholar]
  9. Kirimura K., Sarangbin S., Rugsaseel S., Usami S. Citric acid production by 2-deoxyglucose-resistant mutant strains of Aspergillus niger. Appl Microbiol Biotechnol 1992; 36:573–577
    [Google Scholar]
  10. Kratky Z., Biely P., Bauer S. Mechanism of 2-deoxy-D-glucose inhibition of cell wall polysaccharide and glycoprotein biosynthesis in Saccharowyces cerevisiae. Eur J Biochew 1975; 54:459–467
    [Google Scholar]
  11. Moore D. Effects of hexose analogues on fungi: mechanisms of inhibition and resistance. New Phytologist 1981; 87:487–515
    [Google Scholar]
  12. Pall M.L. Adenosine 3',5'-phosphate in fungi. Microbiol Rev 1981; 45:462–480
    [Google Scholar]
  13. Schuddemat J., Van Den Broek P.J.A., Van Steveninck J. The influence of ATP on sugar uptake mediated by the constitutive glucose carrier of Saccharowyces cerevisiae. Biochiw Biophys Acta 1988; 937:81–87
    [Google Scholar]
  14. St Leger R.J., Charnley A.K., Cooper R.M. Cuticle-degrading enzymes of entomopathogenic fungi: synthesis in culture on cuticle. J Invertebr Pathol 1986a; 48:85–95
    [Google Scholar]
  15. St Leger R.J., Charnley A.K., Cooper R.M. Enzymatic characterization of entomopathogens with the API ZYM system. J. Invertebr Pathol 1986b; 48:375–376
    [Google Scholar]
  16. St Leger R.J., Durrands P.K., Cooper R.M., Charnley A.K. Regulation of production of proteolytic enzymes by the entomopathogenic fungus Metarhiafuw anisopliae. Arch Microbiol 1988; 150:13–416
    [Google Scholar]
  17. St Leger R.J., Roberts D.W., Staples R.C. Novel GTP-binding proteins in plasma membranes of the fungus Metarhivpuw anisopliae. Biochew Biophys Res Coww 1989a; 164:562–566
    [Google Scholar]
  18. St Leger R.J., Roberts D.W., Staples R.C. Calcium and calmodulin-mediated protein synthesis and protein phosphorylation during germination, growth and protease production by Metarhifum anisopliae. J Gen Microbiol 1989b; 135:2141–2154
    [Google Scholar]
  19. St Leger R.J., Laccetti L.B., Staples R.C., Roberts D.W. Protein kinases in the entomopathogenic fungus Metarhifuw anisopliae. J Gen Microbiol 1990a; 136:1401–1411
    [Google Scholar]
  20. St Leger R.J., Butt T.M., Staples R.C., Roberts D.W. Second messenger involvement in differentiation of the entomopathogenic fungus Metarhifiuw anisopliae. J Gen Microbiol 1990b; 136:1779–1789
    [Google Scholar]
  21. St Leger R.J., Roberts D.W., Staples R.C. Electrophoretic detection of multiple protein kinases in the entomopathogenic fungus Metarhf iuw anisopliae. Arch Microbiol 1990c; 154:518–520
    [Google Scholar]
  22. St Leger R.J., Roberts D.W., Staples R.C. A model to explain differentiation of appressoria by germlings of Metarhisfuw anisopliae. J Invertebr Pathol 1991; 57:299–310
    [Google Scholar]
  23. St Leger R.J., May B., Allee L., L, Frank D.C., Roberts D.W. Genetic differences in allozymes and in formation of infection structures among isolates of the entomopathogenic fungus Metarhipiuw anisopliae. J Invertebr Pathol 1992; 60:89–101
    [Google Scholar]
  24. Thevelein J.M., Beullens M. Cyclic AMP and the stimulation of trehalase activity in the yeast Saccharowyces cerevisiae by carbon sources, nitrogen sources and inhibitors of protein synthesis. J Gen Microbiol 1985; 131:3199–3209
    [Google Scholar]
  25. Van Mulders R.M., Van Laere A.J. Cyclic AMP, trehalose and germination of Phycowyces blakesleeanus spores. J. Gen Microbiol 1984; 130:540–547
    [Google Scholar]
  26. Zimmermann F.K., Scheel I. Mutants of Saccharowyces cerevisiae resistant to carbon catabolite repression. Mol and Gen Genet 1977; 154:75–82
    [Google Scholar]
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