1887

Abstract

(Zygomycota) is a facultative saprobe that is a pathogen of many insect species. Almost 2000 expressed sequence tag (EST) cDNA clones were sequenced to analyse gene expression during growth on insect cuticle. Sixty percent of the ESTs that could be clustered into functional groups (⩽10) had their best hits among fungal sequences. These included chitinases and multiple subtilisins, trypsin, metalloprotease and aspartyl protease activities with the potential to degrade host tissues and disable anti-microbial peptides. Otherwise, compared to the ascomycete entomopathogen , produced many fewer types of hydrolases (e.g. no phospholipases), antimicrobial agents, toxic secondary metabolites and no ESTs with putative roles in the generation of antibiotics. Instead, produced a much higher proportion of ESTs encoding ribosomal proteins and enzymes of intermediate metabolism that facilitate its rapid growth. These results are consistent with having adapted a modification of the saprophytic ruderal-selected strategy, using rapid growth to overwhelm the host and exploit the cadaver before competitors overrun it. This strategy does not preclude specialization to pathogenicity, as produces the greatest complexity of proteases on insect cuticle, indicating an ability to respond to conditions in the cuticle.

Loading

Article metrics loading...

/content/journal/micro/10.1099/mic.0.26252-0
2003-07-01
2019-10-22
Loading full text...

Full text loading...

/deliver/fulltext/micro/149/7/mic1491893.html?itemId=/content/journal/micro/10.1099/mic.0.26252-0&mimeType=html&fmt=ahah

References

  1. Aisen, P., Enns, C. & Wessling-Resnick, M. ( 2001; ). Chemistry and biology of eukaryotic iron metabolism. Int J Biochem Cell Biol 33, 940–959.[CrossRef]
    [Google Scholar]
  2. Altschul, S. F., Madden, T. L., Schaffer, A. A., Zhang, J., Zhang, Z., Miller, W. & Lipman, D. J. ( 1997; ). Gapped blast and psi-blast: a new generation of protein database search programs. Nucleic Acids Res 17, 3389–3402.
    [Google Scholar]
  3. Aquino-Pinero, E. E. & Rodriguez del Valle, N. ( 1997; ). Different protein kinase C isoforms are present in the yeast and mycelium forms of Sporothrix schenckii. Mycopathologia 138, 109–115.[CrossRef]
    [Google Scholar]
  4. Benny, G. L., Humber, R. A. & Morton, J. B. ( 2001; ). Zygomycota: Zygomycetes. In The Mycota 7A, pp. 113–146. Edited by D. J. McLaughlin, E. G. McLaughlin & P. A. Lemke. Berlin, Heidelberg: Springer.
  5. Berbee, M. L. & Taylor, J. W. ( 2001; ). Fungal molecular evolution: gene trees and geologic time. In The Mycota 7A, pp. 229–245. Edited by D. J. McLaughlin, E. G. McLaughlin & P. A. Lemke. Berlin, Heidelberg: Springer.
  6. Clark, S. J., Templeton, M. D. & Sullivan, P. A. ( 1997; ). A secreted aspartic proteinase from Glomerella cingulata: purification of the enzyme and molecular cloning of the cDNA. Microbiology 143, 1395–1403.[CrossRef]
    [Google Scholar]
  7. Cooke, R. C. & Rayner, A. D. M. ( 1984; ). Ecology of Saprotrophic Fungi. London: Longman.
  8. Evans, H. C. ( 1989; ). Mycopathogens of insects of epigeal and aerial habitats. In Insect–Fungus Interactions, pp. 205–238. Edited by N. Wilding, N. M. Collins, P. M. Hammond & J. F. Webber. London: Academic Press.
  9. Freimoser, F. M., Screen, S., Baga, S., Hu, G. & St. Leger R. J. ( 2003; ). Expressed sequence tag (EST) analysis of two subspecies of Metarhizium anisopliae reveals a plethora of secreted proteins with potential activity in insect hosts. Microbiology 149, 239–247.[CrossRef]
    [Google Scholar]
  10. Garnier, A., Berredjem, A. & Botton, B. ( 1997; ). Purification and characterization of the NAD-dependent glutamate dehydrogenase in the ectomycorrhizal fungus Laccaria bicolor (Maire) orton. Fungal Genet Biol 22, 168–176.[CrossRef]
    [Google Scholar]
  11. Gray, G. L., Hayenga, K., Cullen, D., Wilson, L. J. & Norton, S. ( 1986; ). Primary structure of Mucor miehei aspartyl protease: evidence for a zymogen intermediate. Gene 48, 41–53.[CrossRef]
    [Google Scholar]
  12. Hajek, A. E. ( 1997; ). Ecology of terrestrial fungal entomopathogens. Adv Micro Ecol 15, 193–249.
    [Google Scholar]
  13. Heintzen, C., Loros, J. J. & Dunlap, J. C. ( 2001; ). The PAS protein vivid defines a clock-associated feedback loop that represses light input, modulates gating, and regulates clock resetting. Cell 104, 453–464.[CrossRef]
    [Google Scholar]
  14. Huang, X. & Madan, A. ( 1999; ). CAP3: a DNA sequence assembly program. Genome Res 9, 868–877.[CrossRef]
    [Google Scholar]
  15. Humber, R. A. ( 1984; ). Foundations for an evolutionary classification of the Entomophthorales (Zygomycetes). In Fungus–Insect Relationships: Perspectives in Ecology and Evolution, pp. 166–183. Edited by Q. Wheeler & M. Blackwell. New York: Columbia University Press.
  16. Iwanaga, S. & Kawabata, S. ( 1998; ). Evolution and phylogeny of defense molecules associated with innate immunity in horseshoe crab. Front Biosci 3, 973–984.
    [Google Scholar]
  17. Jensen, A. B., Gargas, A., Eilenberg, J. & Rosendahl, S. ( 1998; ). Relationships of the insect-pathogenic order Entomophthorales (Zygomycota, Fungi) based on the phylogenetic analysis of small ribosomal sequences (SSU rDNA). Fungal Genet Biol 24, 325–334.[CrossRef]
    [Google Scholar]
  18. Joshi, L. & St. Leger, R. J. ( 1999; ). Cloning, expression, and substrate specificity of MeCPA, a zinc carboxypeptidase that is secreted into infected tissues by the fungal entomopathogen Metarhizium anisopliae. J Biol Chem 274, 9803–9811.[CrossRef]
    [Google Scholar]
  19. Leoni, L., Ciervo, A., Orsi, N. & Visca, P. ( 1996; ). Iron-regulated transcription of the pvdA gene in Pseudomonas aeruginosa: effect of Fur and PvdS on promoter activity. J Bacteriol 178, 2299–2313.
    [Google Scholar]
  20. Meierjohann, S., Walter, R. D. & Muller, S. ( 2002; ). Glutathione synthetase from Plasmodium falciparum. Biochem J 363, 833–838.[CrossRef]
    [Google Scholar]
  21. Papierok, B. ( 1986; ). Some noteworthy biological problems within the genus Conidiobolus. In Fundamental and Applied Aspects of Invertebrate Pathology, pp. 197–200. Edited by R. A. Samson, J. M. Vlak & D. Peter. Wageningen: Foundation of the Fourth International Colloquium of Invertebrate Pathology.
  22. Pirozynski, K. A. & Hawksworth, D. L. ( 1988; ). Coevolution of fungi with plants and animals: introduction and overview. In Coevolution of Fungi with Plants and Animals, pp. 1–29. Edited by K. A. Pirozynski & D. L. Hawksworth. London: Academic Press.
  23. Roberts, D. W. & Humber, R. A. ( 1981; ). Entomogenous fungi. In Biology of Conidial Fungi, pp. 201–236. London: Academic Press.
  24. Royet, J., Bouwmeester, T. & Cohen, S. M. ( 1998; ). Notchless encodes a novel WD40-repeat-containing protein that modulates Notch signaling activity. EMBO J 17, 7351–7360.[CrossRef]
    [Google Scholar]
  25. Schumacher, M. M., Enderlin, C. S. & Selitrennikoff, C. P. ( 1997; ). The osmotic-1 locus of Neurospora crassa encodes a putative histidine kinase similar to osmosensors of bacteria and yeast. Curr Microbiol 34, 340–347.[CrossRef]
    [Google Scholar]
  26. Sirakova, T. D., Markaryan, A. & Kolattukudy, P. E. ( 1994; ). Molecular cloning and sequencing of the cDNA and gene for a novel elastinolytic metalloproteinase from Aspergillus fumigatus and its expression in Escherichia coli. Infect Immun 62, 4208–4218.
    [Google Scholar]
  27. St. Leger, R. J. & Screen, S. E. ( 2000; ). In vitro utilization of mucin, lung polymers, plant cell walls and insect cuticle by Aspergillus fumigatus, Metarhizium anisopliae and Haematonectria haematococca. Mycol Res 104, 463–471.[CrossRef]
    [Google Scholar]
  28. St. Leger, R. J. & Screen, S. E. ( 2001; ). Prospects for strain improvement of fungal pathogens of insects and weeds. In Fungal Biocontrol Agents: Progress, Problems and Potential, pp. 219–238. Edited by T. M. Butt, C. Jackson & N. Morgan. Wallingford: CABI.
  29. St. Leger, R. J., Charnley, A. K. & Cooper, R. M. ( 1986; ). Cuticle-degrading enzymes of entomopathogenic fungi: synthesis in culture on cuticle. J Invertebr Pathol 48, 85–95.[CrossRef]
    [Google Scholar]
  30. St. Leger, R. J., Charnley, A. K. & Cooper, R. M. ( 1987; ). Characterization of cuticle-degrading proteases produced by the entomopathogen Metarhizium anisopliae. Arch Biochem Biophys 253, 221–232.[CrossRef]
    [Google Scholar]
  31. St. Leger, R. J., Durrands, P. K., Cooper, R. M. & Charnley, A. K. ( 1988; ). Regulation of production of proteolytic enzymes by the entomopathogenic fungus Metarhizium anisopliae. Arch Microbiol 150, 413–416.[CrossRef]
    [Google Scholar]
  32. St. Leger, R. J., Bidochka, M. J. & Roberts, D. W. ( 1994; ). Isoforms of the cuticle-degrading Pr1 proteinase and production of a metalloproteinase by Metarhizium anisopliae. Arch Biochem Biophys 313, 1–7.[CrossRef]
    [Google Scholar]
  33. St. Leger, R. J., Joshi, L., Bidochka, M. J. & Roberts, D. W. ( 1996; ). Construction of an improved mycoinsecticide overexpressing a toxic protease. Proc Natl Acad Sci U S A 93, 6349–6354.[CrossRef]
    [Google Scholar]
  34. St. Leger, R. J., Joshi, L. & Roberts, D. W. ( 1997; ). Adaptation of proteases and carbohydrases of saprophytic, phytopathogenic and entomopathogenic fungi to the requirements of their ecological niches. Microbiology 143, 1983–1992.[CrossRef]
    [Google Scholar]
  35. St. Leger, R. J., Nelson, J. O. & Screen, S. E. ( 1999; ). The entomopathogenic fungus Metarhizium anisopliae alters ambient pH, allowing extracellular protease production and activity. Microbiology 145, 2691–2699.
    [Google Scholar]
  36. Stefani, R. M. & Gomes, S. L. ( 1995; ). A unique intron-containing hsp70 gene induced by heat shock and during sporulation in the aquatic fungus Blastocladiella emersonii. Gene 152, 19–26.[CrossRef]
    [Google Scholar]
  37. Sterling, D., Reithmeier, R. A. F. & Casey, J. R. ( 2001; ). A transport metabolon: functional interaction of carbogenic anhydrase II and chloride/bicarbonate exchangers. J Biol Chem 276, 47886–47894.
    [Google Scholar]
  38. Tonukari, N. J., Scott-Craig, J. S. & Walton, J. D. ( 2000; ). The Cochliobolus carbonum SNF1 gene is required for cell wall-degrading enzyme expression and virulence on maize. Plant Cell 12, 237–248.[CrossRef]
    [Google Scholar]
  39. Voigt, K. & Woestermeyer, J. ( 2001; ). Phylogeny and origin of 82 zygomycetes from all 54 genera of the Mucorales and Mortierellales based on combined analysis of actin and translation elongation factor EF-alpha genes. Gene 270, 113–120.[CrossRef]
    [Google Scholar]
  40. Weinberg, E. D. ( 1999; ). The role of iron in protozoan and fungal infectious disease. J Euk Microbiol 46, 231–238.[CrossRef]
    [Google Scholar]
  41. Wu, G. S., Shortt, B. J., Lawrence, E. B., Leon, J., Fitzsimmons, K. C., Levine, E. B., Raskin, I. & Shah, D. M. ( 1997; ). Activation of host defense mechanisms by elevated production of H2O2 in transgenic plants. Plant Physiol 115, 427–435.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/mic.0.26252-0
Loading
/content/journal/micro/10.1099/mic.0.26252-0
Loading

Data & Media loading...

Supplements

vol. 149 , part 7, pp. 1893-1900

A table of ESTs of with significant blast hits in the NCBI protein database is available as an Acrobat PDF file.



PDF
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error