FLO8 deletion leads to decreased adhesion and virulence with downregulated expression of EPA1 , EPA6 , and EPA7 in Candida glabrata

Background The Candida glabrata does not develop into a pathogenic hiphal form; however, it has become the second most common pathogen of fungal infections in humans, partly because of its adhesion ability and virulence. Objectives The present study aimed to determine whether Flo8, a transcription factor that plays an important role in the virulence and drug resistance in Candida albicans , has a similar role in C. glabrata . Methods We constructed FLO8 null strains of a C. glabrata standard strain and eight clinical strains from different sources, and a FLO8 complemented strain. Real-time quantitative PCR, biofilm formation assays, hydrophobicity tests, adhesion tests, Caenorhabditis elegans survival assay, and drug-susceptibility were then performed. Results Compared with the wild-type strains, the biofilm formation, hydrophobicity, adhesion, and virulence of the FLO8 -deficient strains decreased, accompanied by decreased expression of EPA1 , EPA6 , and EPA7 . On the other hand, it showed no changes in antifungal drug resistance, although the expression levels of CDR1 , CDR2 , and SNQ2 increased after FLO8 deletion. Conclusions These results indicated that Flo8 is involved in the adhesion and virulence of C. glabrata , with FLO8 deletion leading to decreased expression of EPA1 , EPA6 , and EPA7 and decreased biofilm formation, hydrophobicity, adhesion, and virulence.