Unique Cell Surface Mannan of Yeast Pathogen <i>Candida auris</i> with Selective Binding to IgG

Abstract

The emerging, multidrug-resistant yeast pathogen <i>Candida auris</i> is responsible for healthcare-associated outbreaks across the globe with high mortality. The rapid spread of <i>C. auris</i> is linked to its successful colonization of human skin, followed by bloodstream infections. We compared glycomics and proteomics of <i>C. auris</i> to closely and distantly related human pathogenic yeasts, <i>C. haemulonii</i> and <i>C. albicans</i>, with the aim to understand the role of cell surface molecules in skin colonization and immune system interactions. <i>Candida auris</i> mannan is distinct from other pathogenic <i>Candida</i> species, as it is highly enriched in β-1,2-linkages. The experimental data showed that <i>C. auris</i> surface mannan β-1,2-linkages were important for the interactions with the immune protein IgG, found in blood and in sweat glands, and with the mannose binding lectin, found in the blood. <i>Candida auris</i> mannan binding to IgG was from 12- to 20-fold stronger than mannan from the more common pathogen <i>C. albicans</i>. The findings suggest unique <i>C. auris</i> mannan could be crucial for the biology and pathogenesis of this emerging pathogen.