Preliminary Studies on a Hyphaforming Mutant of Cryptococcus Neoformans

Mechanisms of unisexual mating in Cryptococcus neoformans

“…Based on this discovery and the observations of C. neoformans cells in pseudohyphal or hyphal form (Freed et al, 1971;Gazzoni et al, 2009;Lurie and Shadomy, 1971;Shadomy and Utz, 1966;Staib et al, 1977;Williamson et al, 1996), Kwon-Chung hypothesized that C. neoformans was a heterothallic basidiomycete, capable of mating with a sexually compatible partner to complete the sexual cycle ( Fig. 1) (Kwon-Chung, 1975).…”

“…Hyphal formation was documented in some a isolates in the absence of an opposite mating partner even before the traditional aa mating was discovered (Erke and Schneidau, 1973;Shadomy and Utz, 1966). Several early investigations demonstrated that hyphal production occurs in haploid strains of C. neoformans and is induced by environmental factors identical to those conducive for bisexual mating, such as nitrogen starvation and dehydration (Erke, 1976;Erke and Schneidau, 1973;Lin et al, 2005;Shadomy and Utz, 1966;Wickes et al, 1996).…”

Unusual morphologies of Cryptococcus spp. in tissue specimens: report of 10 cases

“…have also been reported in a subcutaneous, erythematous nodule 17 . In 1971, a murine model study demonstrated hyphae-formation in 11 strains of this yeast 21,22 . Interestingly, BAVA et al 2 concluded that the pseudohyphae should be considered a virulence factor and that great immunological deficit and further clinical evolution will better enable the fungal cells to produce atypical forms instead of the conventional yeast forms.…”

Fungal Morphogenesis

“…During the context of infection, this fungus grows within the human host almost exclusively in a budding, yeast-like form. Detailed histopathological studies have shown that hyphal forms are rarely encountered during human C. neofor-mans infections, with elongated fungal morphologies observed only as rare variants among clinical strains (Baker and Haugen 1955;Shadomy and Utz 1966). In addition to the typical yeast-cell budding dynamics, other morphological events are required for specific aspects of C. neoformans pathogenesis.…”