The human pathobiont Malassezia furfur secreted protease Mfsap1 regulates cell dispersal and exacerbates skin inflammation

Significance Our skin is the primary exposure site of external microbiota, including the dominant fungus, Malassezia. The continual exchange of communication molecules between the microbes and the host enables host immune system sensing and response to the microbiota and vice versa. Here, we show that a Malassezia secretory protease causes increased inflammation in barrier-compromised skin and has important roles in enabling a planktonic cellular state that can potentially aid in colonization. Malassezia secretory proteases alter their external environment through proteolytic cleavage of extracellular host and microbial proteins, and control Malassezia cell adhesion. Taken together, our study shows these ubiquitous fungal proteases can be beneficial in healthy individuals but become virulence factors in individuals with a compromised skin barrier.