Pathogenic budding yeasts isolated outside of clinical settings

• Published in: FEMS yeast research 2019-05, Vol.19 (3), p.1
• Main Authors: Opulente, Dana A, Langdon, Quinn K, Buh, Kelly V, Haase, Max A B, Sylvester, Kayla, Moriarty, Ryan V, Jarzyna, Martin, Considine, Samantha L, Schneider, Rachel M, Hittinger, Chris Todd
• Format: Article
• Language: English
• Subjects: BASIC BIOLOGICAL SCIENCES; Candida - isolation & purification; Candida - pathogenicity; Candida albicans; Candida glabrata; Candida tropicalis; Candidiasis; Commensals; ecology; Environmental aspects; Fruit - microbiology; Health; Infection; Microbial Sensitivity Tests; Mycoses; Opportunist infection; pathogen; Pathogenic microorganisms; Pathogens; Physiological aspects; Pichia - isolation & purification; Plants (Organisms); Plants - microbiology; Saccharomycetales - classification; Saccharomycetales - isolation & purification; Saccharomycetales - pathogenicity; Setting (Literature); Soil Microbiology; Species; United States; wild yeasts; Yeast; Yeasts (Fungi)
• ISSN: 1567-1356; 1567-1364; 1567-1364
• DOI: 10.1093/femsyr/foz032

ABSTRACT Budding yeasts are distributed across a wide range of habitats, including as human commensals. However, under some conditions, these commensals can cause superficial, invasive, and even lethal infections. Despite their importance to human health, little is known about the ecology of these opportunistic pathogens, aside from their associations with mammals and clinical environments. During a survey of approximately 1000 non-clinical samples across the United States of America, we isolated 54 strains of budding yeast species considered opportunistic pathogens, including Candida albicans and Candida (Nakaseomyces) glabrata. We found that, as a group, pathogenic yeasts were positively associated with fruits and soil environments, whereas the species Pichia kudriavzevii (syn. Candida krusei syn. Issatchenkia orientalis) had a significant association with plants. Of the four species that cause 95% of candidiasis, we found a positive association with soil. These results suggest that pathogenic yeast ecology is more complex and diverse than is currently appreciated and raises the possibility that these additional environments could be a point of contact for human infections. Here we describe the isolation of more than 50 strains of budding yeast opportunistic pathogens from natural settings, suggesting that they have more complex ecology than is currently appreciated.