Environmental pH modulates biofilm formation and matrix composition in <i>Candida albicans</i> and <i>Candida glabrata</i>

<i>Candida</i> species are fungal opportunistic pathogens capable of colonizing and infecting various human anatomical sites, where they have to adapt to distinct niche-specific pH conditions. The aim of this study was to analyse the features of <i>Candida albicans</i> and <i>Candida glabrata</i> biofilms developed under neutral and vaginal acidic (pH 4) conditions. <i>C. albicans</i> produced thicker and more filamentous biofilms under neutral than under acidic conditions. On the other hand, the formation of biofilms by <i>C. glabrata</i> was potentiated by the acidic conditions suggesting the high adaptability of this species to the vaginal environment. In general, both species developed biofilms containing higher amounts of matrix components (protein and carbohydrate) under neutral than acidic conditions, although the opposite result was found for one <i>C. glabrata</i> strain. Overall, this study contributes to a better understanding of the modulation of <i>C. albicans</i> and <i>C. glabrata</i> virulence by specific pH conditions.