Phenotypic switch Candidozyma auris (Candida auris) modulates biofilm formation and virulence genes SAP5 and ALS5 in mono- and co-culture environments with Staphylococcus aureus.

Candidozyma auris (formerly Candida auris) (C. auris), an emerging multidrug-resistant fungal pathogen, forms biofilms as a virulence factor. This study aimed to determine the effect of phenotypic switch on C. auris biofilm formation and virulence gene expression in mono- and co-culture with Staphylococcus aureus. Phenotypic switching was induced by prolonged incubation, and biofilms were developed in RPMI-1640, YEPD, SDB, and BHIYE. The biofilm biomass and total cell count were measured. SAP5 and ALS5 gene expression was quantified using qPCR. The 4th switched generation mono-culture biofilm in BHIYE produced the highest biomass (3.34 ± 0.08) and total cell count (5.66 ± 0.03 log10 cells mL-1). In addition, SAP5 and ALS5 expression peaked in the 2nd switched generation mono-culture by 10.43 ± 0.44-fold and 4.764 ± 0.01-fold, respectively. Co-culture biofilms exhibited significantly higher ALS5 expression in selected switched generations compared to unswitched C. auris (p < 0.05). In conclusion, phenotypic switching enhanced biofilm formation and modulated the expression of SAP5 and ALS5 in C. auris.