Rapid evolution of an adaptive multicellular morphology of Candida auris during systemic infection

Abstract

Candida auris has become a serious threat to public health. The mechanisms of how this fungal pathogen adapts to the mammalian host are poorly understood. Here we report the rapid evolution of an adaptive C. auris multicellular aggregative morphology in the murine host during systemic infection. C. auris aggregative cells accumulate in the brain and exhibit obvious advantages over the single-celled yeast-form cells during systemic infection. Genetic mutations, specifically de novo point mutations in genes associated with cell division or budding processes, underlie the rapid evolution of this aggregative phenotype. Most mutated C. auris genes are associated with the regulation of cell wall integrity, cytokinesis, cytoskeletal properties, and cellular polarization. Moreover, the multicellular aggregates are notably more recalcitrant to the host antimicrobial peptides LL-37 and PACAP relative to the single-celled yeast-form cells. Overall, to survive in the host, C. auris can rapidly evolve a multicellular aggregative morphology via genetic mutations.

Going fishing: how to get what you want from a fungal genetic screen

“…Therefore, when we started to investigate C. auris, our focus was to identify mutants that were unable to adhere to surfaces ( 2 ). Another major focus was on mutants that showed altered morphology, as multiple aggregating strains have been isolated from patients ( 3 – 5 ); screening for altered morphology was the focus of two recent insertional mutagenesis screens ( 6 , 7 ). In other fungi, the interesting biological phenomena and topics of screens range from identifying regulators of sex and meiosis ( 8 ), defining essential genes ( 9 – 11 ), identifying kinases that regulate morphogenesis ( 12 ), determining modulators of host immune responses ( 13 – 15 ), or identifying new potential avenues for antifungal therapies ( 16 – 19 ), to name a few.…”