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Biolistic Transformation of a Fluorescent Tagged Gene into the Opportunistic Fungal Pathogen Cryptococcus neoformans
07:32

Biolistic Transformation of a Fluorescent Tagged Gene into the Opportunistic Fungal Pathogen Cryptococcus neoformans

Published on: March 19, 2015

Long-distance dispersal and recombination in environmental populations of Cryptococcus neoformans var. grubii from

Sanjay S Hiremath1, Anuradha Chowdhary2, Tusharantak Kowshik2

  • 1Center for Environmental Genomics, Department of Biology, McMaster University, Hamilton, ON L8S 4K1, Canada.

Microbiology (Reading, England)
|May 3, 2008
PubMed

Insights

Environmental Cryptococcus neoformans var. grubii populations in decaying wood in India show evidence of recombination, suggesting long-distance dispersal. This study analyzed 78 isolates, finding no significant genetic differentiation across geographical or host tree species.

Area of Science:

  • Mycology
  • Population Genetics
  • Environmental Microbiology

Background:

  • Cryptococcus neoformans causes significant disease in immunocompromised individuals globally.
  • Infections are primarily acquired through inhalation of environmental spores, making environmental population studies crucial for understanding its ecology and epidemiology.
  • Decaying wood is a known niche for C. neoformans, but its population structure in this habitat is poorly understood.

Purpose of the Study:

  • To investigate the population structure of Cryptococcus neoformans var. grubii in decaying wood environments in north-western India.
  • To assess genetic differentiation among C. neoformans populations based on geographical location and host tree species.
  • To explore the extent of recombination within environmental C. neoformans populations.

Main Methods:

  • Sampling of C. neoformans var. grubii from decaying wood in tree hollows across five locations in India.
  • Multilocus sequence typing (MLST) using five gene fragments for 78 isolates.
  • Population-genetic analyses to evaluate genetic differentiation and recombination.

Main Results:

  • All 78 analyzed isolates belonged to mating type alpha.
  • No significant genetic differentiation was observed among populations from different geographical areas or host tree species.
  • Unambiguous evidence for recombination was detected, despite the absence of mating type a strains in the sampled population.

Conclusions:

  • Environmental populations of C. neoformans var. grubii in India exhibit recombination, supporting a model of long-distance dispersal.
  • The findings contribute to understanding the ecology and epidemiology of C. neoformans in its environmental reservoir.
  • Further research into the mechanisms of dispersal and recombination in environmental fungal populations is warranted.

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