Identification of ALS1 gene from ALS gene family and Als1 protein of Candida albicans strains isolated from different soft lining materials and acrylic surfaces

The aim of this study was to investigate the differences of ALS1 gene expression in C. albicans cells isolated from different softlining materials, and acrylic surfaces, and to investigate the role of Als1 protein in adhesion to these surfaces. For this purpose; six C. albicans strains isolated from four patients with complete dentures, and two patients without dentures were used. The differences of ALS1 gene expression patterns were evaluated before and after these strains contacted with acrylic resin (Acron Duo) and softlining materials (Visco Gel, Ufi Gel P, Mollosil, Molloplast B) in-vitro using RT-PCR. In addition, differences in protein expression levels of these C. albicans strains were investigated with Western blot and flow cytometry analyses also. Thereby, the expression of gene encoding Als1 protein (Als1p) that is responsible from adhesion mechanism and protein existence on the cell surface were evaluated simultaneously. Results obtained form RT-PCR and Western blot analyses showed that ALS1 and Als1p expression levels were changed in C. albicans strains after exposure to different denture materials. Quantitative investigation with flow cytometry showed that material depended protein expression levels were different. Minimum Als1p expression was obtained from strains contacted with acrylic resin. Protein expression levels in softlining materials were higher than in acrylic resin. Results obtained from Visco Gel and Molloplast B were similar and showed lowest Als1p expression level when softlining materials were compared to each other. Room temperature vulcanized silicone based softlining materials Mollosil and Ufi Gel P showed higher expression than the other two softlining materials. However, there were no significant differences between average Als1p expression levels in softlining materials. With these findings, it was concluded that ALS1 and Als1p expression were affected from the type of denture material at different levels, and Als1p affects the adhesion to restorative materials as it affects the adhesion to epithelial and endothelial cells. Keywords: Candida albicans, ALS1, adhesion, softlining materials