IADR Abstract Archives
Effect of Candida auris-phenotypic switching on co-aggregation with Staphylococcus aureus.
Objectives: This study aimed to determine the effect of phloxine B induced-phenotypic switching on the co-aggregation of C. auris with Staphylococcus aureus.
Methods: Phenotypic switching of C. auris (ATCC MYA-5002) was induced by inoculating the yeast on a yeast extract peptone dextrose (YEPD) agar containing 5 mg/mL of Phloxine B dye and incubated for five days to produce 1st switching generation. The protocol was repeated until the 4th generation. To determine the effect of phenotypic switching on co-aggregation, C. auris and its switched generations were grown in RPMI-1640, YEPD, Sabouraud dextrose (SD) and brain heart infusion yeast extract (BHIYE) broth. Meanwhile, S. aureus (ATCC 25923) was grown in brain heart infusion (BHI) broth. All microorganisms were standardised in a co-aggregation buffer to 106 cells/mL. Auto-aggregation was determined by measuring the absorbance difference at OD620nm (ΔAbs) between 0 h and 1 h at room temperature of a similar kingdom. In contrast, co-aggregation was determined by combining two kingdoms in the same 2-mL Eppendorf tube.
Results: All BHIYE-grown C. auris had higher auto-aggregation than the other growth media (8.2±0.3% to 9.2±0.1%). Co-aggregation of C. auris with S. aureus exhibited the highest in the 1st generation in BHIYE (12.1±3.4%), followed by the 2nd generation (3.0±0.0%) in the same medium. In addition, decreased ΔAbs% in co-aggregation were observed for the 3rd and 4th switched generations in all growth media compared to the auto-aggregation.
Conclusions: C. auris and switched generations interact antagonistically with S. aureus in planktonic, and the aggregation of the yeast is strain dependent.
Methods: Phenotypic switching of C. auris (ATCC MYA-5002) was induced by inoculating the yeast on a yeast extract peptone dextrose (YEPD) agar containing 5 mg/mL of Phloxine B dye and incubated for five days to produce 1st switching generation. The protocol was repeated until the 4th generation. To determine the effect of phenotypic switching on co-aggregation, C. auris and its switched generations were grown in RPMI-1640, YEPD, Sabouraud dextrose (SD) and brain heart infusion yeast extract (BHIYE) broth. Meanwhile, S. aureus (ATCC 25923) was grown in brain heart infusion (BHI) broth. All microorganisms were standardised in a co-aggregation buffer to 106 cells/mL. Auto-aggregation was determined by measuring the absorbance difference at OD620nm (ΔAbs) between 0 h and 1 h at room temperature of a similar kingdom. In contrast, co-aggregation was determined by combining two kingdoms in the same 2-mL Eppendorf tube.
Results: All BHIYE-grown C. auris had higher auto-aggregation than the other growth media (8.2±0.3% to 9.2±0.1%). Co-aggregation of C. auris with S. aureus exhibited the highest in the 1st generation in BHIYE (12.1±3.4%), followed by the 2nd generation (3.0±0.0%) in the same medium. In addition, decreased ΔAbs% in co-aggregation were observed for the 3rd and 4th switched generations in all growth media compared to the auto-aggregation.
Conclusions: C. auris and switched generations interact antagonistically with S. aureus in planktonic, and the aggregation of the yeast is strain dependent.