Development of Congenic Mutants and Genetic Analysis of Virulence in Cryptococcus Neoformans

Abstract

Cryptococcus neoformans strains were isolated from clinical source taken from the University of Benin Teaching Hospital (UBTH) and environmental source taken from New Benin Market.  Two strains were selected; clinical isolate 4832 and environmental isolate NBM5. They were determined to be of two different mating types, due to differences in their susceptibility to the antifungal agent fluconazole. In order to check the involvement of mating type locus in the virulence of C. neoformans, congenic mutants were developed. Based on genetic analysis, the mating type locus in synergy with other loci influence the virulence in C. neoformans. Genetic recombination in this organism unfolds the reality of horizontal gene transfer in C. neoformans which could also apply to other organisms. In conclusion, most resistance of microbial organism to antibiotics could be as a result of the genetic recombination following selection.