You might have been told never to kick somebody when they’re down, but the fungus Candida albicans certainly won’t waste an opportunity. It usually lives harmlessly within our gut, but can invade the tissues of patients with weakened immune defences, such as those suffering from HIV, causing fatal infections. Pictured, the fungi are extending projections known as hyphae (shown in green) into cells of the intestine (in red, nuclei shown in blue). However, they have a weakness we could use to fight back: Candida cells can’t invade without a functional vacuole. This cellular compartment is used to degrade waste products, and must be kept acidic by the action of a proton pump. Cells in which the pump was inactivated no longer caused fatal infections in mice; these results suggest that developing drugs that affect the pH of the vacuole may be a promising route towards fighting the fungus.
Written by Emmanuelle Briolat
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