Natural heterozygosity in Candida albicans

Publisher Website
Google Scholar
Abstract
C. albicans clinical isolates (16) were subjected to UV radiation and the survivors tested for auxotrophy. Six isolates displayed strongly biased auxotroph spectra: 3 yielded methionine auxotrophs, 2 yielded isoleucinevaline and adenine auxotrophs and one yielded lysine auxotrophs. Evidence that auxotrophs arise by segregation from naturally occurring heterozygous states is presented. The remaining isolates yielded few or no auxotrophs in an arbitrary sample (> 2500) of survivors of irradiation. C. albicans evidently is diploid, although aneuploidy (2n + i) cannot be rigorously excluded. The possible utility of heterozygosity as a marker in epidemiological studies and a rationale for the frequent occurrence of heterozygosity are discussed.