1887

Abstract

Among species of the heterobasidiomycetous yeasts, is the only serious pathogen that causes fatal infections in both immunocompromised as well as immunocompetent patients. Three phenotypic characteristics, including growth at 37 °C, extracellular polysaccharide capsule and laccase activity, of are known to play major roles in the pathogenicity of the fungus. Several genes involved in polysaccharide capsule formation, as well as the gene encoding a laccase, have previously been cloned and characterized. To analyse the presence of these virulence factors in other heterobasidiomycetous yeasts, numerous species of heterobasidiomycetous yeasts were screened for the presence of laccase activity and a polysaccharide capsule. Species exhibiting laccase activity and possessing a glucuronoxylomannan (GXM) capsule were screened for homologues of both the gene and the gene of . Southern blots of genomic DNA from GXM capsule-producing species exhibited no discernible hybridization to the DNA sequence except for the two varieties of and . Although discernible, the hybridization band observed with the DNA of was faint. Oligonucleotide primers constructed using the gene sequence also failed to yield PCR products from DNAs of these yeasts except for the two varieties of . These results, coupled with the absence of a homologue in the database, suggested the gene to be unique to was the only species besides that possessed a capsule and expressed strong laccase activity on various media containing phenolic compounds. A homologue was isolated from while it was not detected in the species producing beige to faint tan colonies on media with phenolic compounds. Compared to the sequence of four serotypes of , the homologue of showed the highest homology to that of serotype B/C strains and the lowest homology to that of serotype A strains.

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2001-08-01
2024-04-27
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References

  1. Abercrombie M. J., Jons J. K. N., Perry M. B. 1960; The polysaccharides of Cryptococcus laurentii (Y1401). Can J Chem 38:2007–2014 [CrossRef]
    [Google Scholar]
  2. Battacharjee A. K., Kwon-Chung K. J., Glaudemans C. P. J. 1978; The structure of the capsular polysaccharide from Cryptococcus neoformans serotype D. Carbohydr Res 73:183–192
    [Google Scholar]
  3. Boekhout T., Theelen B., Diaz M., Fell J. W., Hop W. C. J., Abeln C. A., Dromer F., Meyer W. 2001; Hybrid genotypes in the pathogenic yeast Cryptococcus neoformans . Microbiology 147:891–907
    [Google Scholar]
  4. Chang Y. C., Kwon-Chung K. J. 1994; Complementation of a capsule-deficient mutation of Cryptococcus neoformans restores its virulence. Mol Cell Biol 14:4912–4919
    [Google Scholar]
  5. Chang Y. C., Kwon-Chung K. J. 1998; Isolation of the third capsule-associated gene, CAP60 , required for virulence in Cryptococcus neoformans . Infect Immun 66:2230–2236
    [Google Scholar]
  6. Chang Y. C., Kwon-Chung K. J. 1999; Isolation, characterization and localization of a capsule associated gene, CAP10 , of Cryptococcus neoformans . J Bacteriol 181:5636–5643
    [Google Scholar]
  7. Chang Y. C., Penoyer L. A., Kwon-Chung K. J. 1996; The second capsule gene of Cryptococcus neoformans, CAP64 , is essential for virulence. Infect Immun 64:1977–1983
    [Google Scholar]
  8. Cherniak R., Jones R. G., Slodki M. E. 1988; Type-specific polysaccharide of Cryptococcus neoformans . n.m.r.-spectral study of a glucuronomannan chemically derived from a Tremella mesenterica exopolysaccharide. Carbohydr Res 182:227–239 [CrossRef]
    [Google Scholar]
  9. Diaz M. R., Boekhout T., Theelen B., Fell J. W. 2000; Molecular sequence analyses of the intergenic spacer (IGS) associated with rDNA of the two varieties of the pathogenic yeast Cryptococcus neoformans . Syst Appl Microbiol 23:535–545 [CrossRef]
    [Google Scholar]
  10. Feinberg A. P., Vogelstein B. 1983; A technique for radiolabeling DNA restriction endonuclease fragments to high specific activity. Anal Biochem 132:6–13 [CrossRef]
    [Google Scholar]
  11. Fell J. W., Boekhout T., Fonseca A., Scorzetti G., Statzell-Talman A. 2000; Biodiversity and systematics of basidiomycetous yeasts as determined by large subunit rD1/D2 domain sequence analysis. Int J Syst Evol Microbiol 50:1351–1371 [CrossRef]
    [Google Scholar]
  12. Franzot S. P., Salkin I. F., Casadevall A. 1999; Cryptococcus neoformans var. grubii : separate varietal status for Cryptococcus neoformans serotype A isolates. J Clin Microbiol 37:838–840
    [Google Scholar]
  13. Fujimura H., Sakuma Y. 1993; Simplified isolation of chromosomal and plasmid DNA from yeast. BioTechniques 14:538–539
    [Google Scholar]
  14. Giardina P., Cannio R., Martirani L., Marzullo L., Palmieri G., Sannia G. 1995; Cloning and sequencing of a laccase gene from the lignin-degrading Basidiomycete Pleurotus ostreatus . Appl Environ Microbiol 61:2408–2413
    [Google Scholar]
  15. Gueho E., Improvisi L., Christen R., de Hoog G. S. 1993; Phylogenetic relationships of Cryptococcus neoformans and some related basidiomycetous yeasts determined from partial large subunit rRNA sequences. Antonie Leeuwenhoek 63:175–189 [CrossRef]
    [Google Scholar]
  16. Ikeda R., Matsuyama H., Nishikawa A., Shinoda T., Fukazawa Y. 1991; Comparison of serological and chemical characteristics of capsular polysaccharides of Cryptococcus neoformans var. neoformans serotype A and Cryptococcus albidus var. albidus. Microbiol Immunol 35:125–138 [CrossRef]
    [Google Scholar]
  17. Krajden S., Summerbell R. C., Kane J. 7 other authors 1991; Normally saprobic Cryptococci isolated from Cryptococcus neoformans infection. J Clin Microbiol 29:1883–1887
    [Google Scholar]
  18. Kwon-Chung K. J. 1975; Description of a new genus, Filobasidiella , the perfect state of Cryptococcus neoformans . Mycologia 67:1197–1200 [CrossRef]
    [Google Scholar]
  19. Kwon-Chung K. J., Bennett J. E. 1992 Medical Mycology pp 397–446 Philadelphia: Lea & Febiger;
    [Google Scholar]
  20. Kwon-Chung K. J., Polacheck I., Popkin T. J. 1982; Melanin-lacking mutants of Cryptococcus neoformans and their virulence for mice. J Bacteriol 150:1414–1421
    [Google Scholar]
  21. Kwon-Chung K. J., Wickes B. L., Stockman L., Roberts G. D., Ellis D., Howard D. H. 1992; Virulence, serotype, and molecular characteristics of environmental strains of Cryptococcus neoformans var . gattii . Infect Immun 60:1869–1874
    [Google Scholar]
  22. Kwon-Chung K. J., Chang Y. C., Bauer R., Swann E. C., Taylor J. W., Goel R. 1995; The characteristics that differentiate Filobasidiella depauperata from Filobasidiella neoformans . Stud Mycol 38:67–79
    [Google Scholar]
  23. Mikuni J., Morohoshi N. 1997; Cloning and sequencing of a second laccase gene from the white-rot fungus Coriolus versicolor . FEMS Microbiol Lett 155:79–84 [CrossRef]
    [Google Scholar]
  24. Nakamura Y., Kano R., Watanabe S., Hasegawa A. 2000; Molecular analysis of CAP59 gene sequences from five serotypes of Cryptococcus neoformans . J Clin Microbiol 38:992–995
    [Google Scholar]
  25. Oberwinkler F. 1987; Heterobasidiomycetes with ontogenetic yeast-stages – systematics and phylogenetic aspects. Stud Mycol 30:61–74
    [Google Scholar]
  26. Peláez F., Martı́nez M. J., Martı́nez A. T. 1995; Screening of 68 species of basidiomycetes for enzymes involved in lignin degradation. Mycol Res 99:37–42 [CrossRef]
    [Google Scholar]
  27. Perry C. R., Smith M., Britnell C. H., Wood D. A. 1993; Identification of two laccase genes in the cultivated mushroom Agaricus bisporus . J Gen Microbiol 139:1209–1218 [CrossRef]
    [Google Scholar]
  28. Polacheck I., Hearing V. I., Kwon-Chung K. J. 1982; Biochemical studies of phenoloxidase and utilization of catecholamines in Cryptococcus neoformans . J Bacteriol 150:1212–1220
    [Google Scholar]
  29. Rhodes J. C., Polacheck I., Kwon-Chung K. J. 1982; Phenoloxidase activity and virulence in isogenic strains of Cryptococcus neoformans . Infect Immun 36:1175–1184
    [Google Scholar]
  30. Salas S. D., Bennett J. E., Kwon-Chung K. J., Perfect J. R., Williamson P. R. 1996; Effect of the laccase gene, CNLAC1 , on virulence of Cryptococcus neoformans . J Exp Med 184:377–386 [CrossRef]
    [Google Scholar]
  31. Slodki M. E. 1966; Hydrolysis products from an extracellular Tremella polysaccharide. Can J Microbiol 12:495–499 [CrossRef]
    [Google Scholar]
  32. Staib F. 1962; Cryptococcus neoformans and Guizotia abyssinica (Syn. G. oleifera D.C.). Z Hyg 148:466–475 [CrossRef]
    [Google Scholar]
  33. Swann E. C., Taylor J. W. 1993; Higher taxa of Basidiomycetes: an 18S rRNA gene perspective. Mycologia 85:923–936 [CrossRef]
    [Google Scholar]
  34. Swinne-Desgain D. 1976; Cryptococcus neoformans in the crops of pigeons following its experimental administration. Sabouraudia 14:313–317 [CrossRef]
    [Google Scholar]
  35. Varma A., Kwon-Chung K. J. 1991; Rapid method to extract DNA from Cryptococcus neoformans . J Clin Microbiol 30:2960–2967
    [Google Scholar]
  36. Williamson P. R. 1994; Biochemical and molecular characterization of the diphenol oxidase of Cryptococcus neoformans : identification as a laccase. J Bacteriol 176:656–664
    [Google Scholar]
  37. Xu J. P. 2000; Multiple gene genealogies reveal recent dispersion and hybridization in the human pathogenic fungus Cryptococcus neoformans . Mol Ecol 9:1497–1481
    [Google Scholar]
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