Pseudohyphae formation in Candida glabrata due to CO2 exposure

Abstract

BACKGROUND AND PURPOSE Formation of pseudohyphae is considered a virulence factor inCandidaspecies. Generally,Candida glabratagrows as budding yeast cells; however, reports illustrated thatC. glabratacould form pseudohyphal cells in response to some stimuli. In this study, we provided insight into the ability ofC. glabratain forming pseudohyphal cells under different levels of carbon dioxide (CO2). MATERIALS AND METHODS Candida glabrata reference strain (ATCC 90030) was used in this study. Yeast samples were cultured on Sabouraud dextrose broth (SDB) medium and incubated under 3%, 5%, and 10% CO2levels for 24, 48 and 72 h. Control cultures were prepared without CO2pressure for three days. The possibility of pseudohyphae and mycelium formation inC. glabratawas investigated. RESULTS The results of this study revealed that the most branching filament-like cells were obtained at high CO2pressure (10%) after 72 h. After three days of low CO2pressure (3%), only yeast and budding cells were observed without any pseudohyphae formation. CONCLUSION CO2could act as a stimulus and induced formation of pseudohyphae inCandida glabratayeast cells.