1887

Abstract

The basidiomycete yeast is a cause of significant morbidity and mortality in immunocompromised hosts throughout the world. The sporadic nature of the infection and the limited empirical evidence for direct human-to-human transmission have led to the belief that infections in humans are predominantly caused by the inhalation of basidiospores from environmental sources. Therefore, analysing the structure of environmental populations of can significantly increase our understanding of its ecology, evolution and epidemiology. Decaying wood is a rich source of organic and inorganic compounds and is known to be a suitable ecological niche for many micro-organisms, including . However, relatively little is known about the population structure of sampled from decaying wood. In this study, we analysed samples of var. colonizing decaying wood in tree hollows of nine tree species in five geographical locations (Delhi, Bulandshahar, Hathras, Amritsar and Amrouli) in north-western India. Multilocus sequence typing was conducted using five gene fragments for each of 78 isolates. All isolates belonged to mating type . Population-genetic analyses identified no evidence for significant differentiation among populations belonging to either different geographical areas or different host tree species. Interestingly, despite the lack of mating type strains in our survey, we found unambiguous evidence for recombination in our population analyses. Our results are consistent with the hypothesis of long-distance dispersal and recombination in environmental populations of this species in India.

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2008-05-01
2024-10-03
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References

  1. Agapow P.-M., Burt A. 2001; Indices of multilocus linkage disequilibrium. Mol Ecol Notes 1:101–102
    [Google Scholar]
  2. Avise J. C. 1994 Molecular Markers, Natural History and Evolution New York: Chapman & Hall;
    [Google Scholar]
  3. Barker F. K., Lutzoni F. M. 2002; The utility of the incongruence length difference test. Syst Biol 51:625–637
    [Google Scholar]
  4. Bennett J. E., Kwon-Chung K. J., Howard D. H. 1977; Epidemiologic differences among serotypes of Cryptococcus neoformans . Am J Epidemiol 105:582–586
    [Google Scholar]
  5. Campbell L. T., Currie B. J., Krockenberger M., Malik R., Meyer W., Heitman J., Carter D. 2005; Clonality and recombination in genetically differentiated subgroups of Cryptococcus gattii . Eukaryot Cell 4:1403–1409
    [Google Scholar]
  6. Casadevall A., Perfect J. R. 1998 Cryptococcus neoformans Washington, DC: ASM Press;
    [Google Scholar]
  7. Casadevall A., Steenbergen J. N., Nosanchuk J. D. 2003; Ready-made virulence and dual use virulence factors in pathogenic environmental fungi – the Cryptococcus neoformans paradigm. Curr Opin Microbiol 6:332–337
    [Google Scholar]
  8. Faith D. P. 1991; Cladistic permutation tests for monophyly and nonmonophyly. Syst Zool 40:366–375
    [Google Scholar]
  9. Farris J. S., Källersjö M., Kluge A. G., Bult C. 1994; Testing significance of incongruence. Cladistics 10:315–319
    [Google Scholar]
  10. Fraser J. A., Giles S. S., Wenink E. C., Geunes-Boyer S. G., Wright J. R., Diezmann S., Allen A., Stajich J. E., Dietrich F. S. other authors 2005; Same-sex mating and the origin of the Vancouver Island Cryptococcus gattii outbreak. Nature 437:1360–1364
    [Google Scholar]
  11. Galtier N., Gouy M., Gautier C. 1996; SeaView and phylo_win, two graphic tools for sequence alignment and molecular phylogeny. Comput Appl Biosci 12:543–548
    [Google Scholar]
  12. Goddard M. R., Godfray H. C. J., Burt A. 2005; Sex increases the efficacy of natural selection in experimental yeast populations. Nature 434:636–640
    [Google Scholar]
  13. Jensen J. L., Bohonak A. J., Kelley S. T. 2005; Isolation by distance, web service v.3.14. BMC Genet 6:13
    [Google Scholar]
  14. Keller S. M., Viviani M. A., Esposto M. C., Cogliati M., Wickes B. L. 2003; Molecular and genetic characterization of a serotype A MAT a Cryptococcus neoformans isolate. Microbiology 149:131–142
    [Google Scholar]
  15. Kidd S. E., Guo H., Bartlett K. H., Xu J., Kronstad J. W. 2005; Comparative gene genealogies indicate that two clonal lineages of Cryptococcus gattii in British Columbia resemble strains from other geographical areas. Eukaryot Cell 4:1629–1638
    [Google Scholar]
  16. Kwon-Chung K. J. 1975; A new genus, Filobasidiella , the perfect state of Cryptococcus neoformans . Mycologia 67:1197–1200
    [Google Scholar]
  17. Kwon-Chung K. J. 1976; Morphogenesis of Filobasidiella neoformans , the sexual state of Cryptococcus neoformans . Mycologia 68:821–833
    [Google Scholar]
  18. Kwon-Chung K. J., Bennett J. E. 1978; Distribution of α and a mating types of Cryptococcus neoformans among natural and clinical isolates. Am J Epidemiol 108:337–340
    [Google Scholar]
  19. 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]
  20. Lazera M. S., Pires F. D., Camillo-Coura L., Nishikawa M. M., Bezerra C. C., Trilles L., Wanke B. 1996; Natural habitat of Cryptococcus neoformans var. neoformans in decaying wood forming hollows in living trees. J Med Vet Mycol 34:127–131
    [Google Scholar]
  21. Lin X., Hull C. M., Heitman J. 2005; Sexual reproduction between partners of the same mating type in Cryptococcus neoformans . Nature 434:1017–1021
    [Google Scholar]
  22. Lin X., Huang J. C., Mitchell T. G., Heitman J. 2006; Virulence attributes and hyphal growth of C. neoformans are quantitative traits and the MATα allele enhances filamentation. PLoS Genet 2:e187
    [Google Scholar]
  23. Lin X., Litvintseva A. P., Nielsen K., Patel S., Floyd A., Mitchell T. G., Heitman J. 2007; α AD α hybrids of Cryptococcus neoformans : evidence of same-sex mating in nature and hybrid fitness. PLoS Genet 3:1975–1990
    [Google Scholar]
  24. Litvintseva A. P., Marra R. E., Nielsen K., Heitman J., Vilgalys R. J., Mitchell T. G. 2003; Evidence of sexual recombination among Cryptococcus neoformans serotype A isolates in sub-Saharan Africa. Eukaryot Cell 2:1162–1168
    [Google Scholar]
  25. Litvintseva A. P., Thakur R., Vilgalys R., Mitchell T. G. 2006; Multilocus sequence typing reveals three genetic subpopulations of Cryptococcus neoformans var. grubii (serotype A), including a unique population in Botswana. Genetics 172:2223–2238
    [Google Scholar]
  26. Loftus B. J., Fung E., Roncaglia P., Rowley D., Amedeo P., Bruno D., Vamathevan J., Miranda M., Anderson I. J. other authors 2005; The genome of the basidiomycetous yeast and human pathogen Cryptococcus neoformans . Science 307:1321–1324
    [Google Scholar]
  27. Maynard-Smith J., Smith N. H., O'Rourke M., Spratt B. G. 1993; How clonal are bacteria?. Proc Natl Acad Sci U S A 90:4384–4388
    [Google Scholar]
  28. Nei M. 1972; Genetic distance between populations. Am Nat 106:283–292
    [Google Scholar]
  29. Nielsen K., Cox G. M., Wang P., Toffaletti D. L., Perfect J. R., Heitman J. 2003; Sexual cycle of Cryptococcus neoformans variety grubii and virulence of congenic a and α isolates. Infect Immun 71:4831–4841
    [Google Scholar]
  30. Randhawa H. S., Kowshik T., Khan Z. U. 2003; Decayed wood of Syzygium cumini and Ficus religiosa living trees in Delhi/New Delhi metropolitan area as natural habitat of Cryptococcus neoformans . Med Mycol 41:199–209
    [Google Scholar]
  31. Randhawa H. S., Kowshik T., Khan Z. U. 2005; Efficacy of swabbing versus a conventional technique for isolation of Cryptococcus neoformans from decayed wood in tree trunk hollows. Med Mycol 43:67–71
    [Google Scholar]
  32. Reimão J. Q., Drummond E. D., Terceti M. de. S., Lyon J. P., Franco M. C., de Siqueira A. M. 2007; Isolation of Cryptococcus neoformans from hollows of living trees in the city of Alfenas, MG. Brazil. Mycoses 50:261–264
    [Google Scholar]
  33. Swofford D. L. 1996; Phylogenetic inference. In Molecular Systematics pp 407–514 Edited by Hill D., Moritz C., Mable B. Sunderland, MA: Sinauer Associates;
    [Google Scholar]
  34. Thompson J. D., Gibson T. J., Plewniak F., Jeanmougin F., Higgins D. G. 1997; The clustal_x–Windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucleic Acids Res 24:4876–4882
    [Google Scholar]
  35. Tintelnot K., Lemmer K., Losert H., Schar G., Polak A. 2004; Follow-up of epidemiological data of cryptococcosis in Austria, Germany and Switzerland with special focus on the characterization of clinical isolates. Mycoses 47:455–464
    [Google Scholar]
  36. Weir B. S. 1996 Genetic Data Analysis II Sunderland: Sinauer;
    [Google Scholar]
  37. Weismann A. 1904 The Evolution Theory 2 vols Translated from the 1904 2nd German edition by J. A. Thomson & M. R. Thomson London: Edward Arnold;
    [Google Scholar]
  38. Wright S. 1938; Size of population and breeding structure in relation to evolution. Science 87:430–431
    [Google Scholar]
  39. Xu J. 2005a; Cost of interacting with sexual partners in a facultative sexual microbe. Genetics 171:1597–1604
    [Google Scholar]
  40. Xu J. 2005b Evolutionary Genetics of Fungi UK: Horizon Bioscience;
    [Google Scholar]
  41. Xu J., Mitchell T. G. 2003; Comparative gene genealogical analyses of strains of serotype AD identify recombination in populations of serotypes A and D in the human pathogenic yeast Cryptococcus neoformans . Microbiology 149:2147–2154
    [Google Scholar]
  42. Xu J., Mitchell T. G., Vilgalys R. 1999; PCR-restriction fragment length polymorphism (RFLP) analyses reveal both extensive clonality and local genetic differentiation in Candida albicans . Mol Ecol 8:59–73
    [Google Scholar]
  43. Xu J., Vilgalys R., Mitchell T. D. 2000; Multiple gene genealogies reveal recent dispersion and hybridization in the human pathogenic fungus Cryptococcus neoformans . Mol Ecol 9:1471–1481
    [Google Scholar]
  44. Xue C., Tada Y., Dong X., Heitman J. 2007; The human fungal pathogen Cryptococcus can complete its sexual cycle during a pathogenic association with plants. Cell Host Microbe 1:263–273
    [Google Scholar]
  45. Yan Z., Li X., Xu J. 2002; Geographic distribution of mating type alleles of Cryptococcus neoformans in four areas of the United States. J Clin Microbiol 40:965–972
    [Google Scholar]
  46. Yan Z., Hull C. M., Sun S., Heitman J., Xu J. 2007; The mating type - specific homeodomain genes SXI1α and SXI2a coordinately control uniparental mitochondrial inheritance in Cryptococcus neoformans . Curr Genet 51:187–195
    [Google Scholar]
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