Discrimination between Candida albicans and Other Pathogenic Species of the Genus Candida by Their Differential Sensitivities to Toxins of a Panel of Killer Yeasts

The differential sensitivities to toxins produced by a short panel of four killer yeasts allowed discrimination between 91 strains of the yeast Candida albicans and 223 non-C. albicans Candida strains. One hundred percent of C. albicans isolates exhibited negative results to the toxin panel, while 100% of non-C. albicans cultures gave well-defined and reproducible positive results to at least one of the four killer toxins. Among C. albicans strains only 96 and 87% gave germ tube (GT)- and chlamydospore-positive results, respectively. In addition a few GT-false-positive strains were detected among non-C. albicans isolates. Susceptibility to the toxin panel is apparently expressed more consistently than either GT or chlamydospore production and may constitute a promising basis for a new simple and easy-to-use procedure for routine discrimination between the species C. albicans and other species of the genus Candida.