We need to talk about Candida tropicalis: Virulence factors and survival mechanisms

Candida tropicalis is a notable species of the Candida genus representing an impressive epidemiology in tropical regions, especially in South America and Asia, where India already presents the species as the first in Candida epidemiology. Candida tropicalis has also shown a worrying antifungal resistance profile in recent years. It is essential to highlight that each pathogenic species of the Candida genus has a particular biology; however, Candida virulence factors are almost entirely based on studies with C. albicans. The intrinsic resistance of C. krusei to some azoles, the intrinsic osmotolerance of C. tropicalis, and the multidrug resistance of C. auris are just a few examples of how the biology of each Candida species is unique. Despite being a phylogenetically close species, C. tropicalis can support 15% NaCl, antagonistically metabolize and signal N-acetylglucosamine, encode 16 reported ALS genes, and other specificities discussed here compared to C. albicans. It is essential to clarify the details of the C. tropicalis infectious process, including identifying the participating secreted enzyme(s), the factors responsible for tissue damage, and the mechanisms underlying the morphogenesis and tolerance signaling pathways. In this review, we thoroughly assembled what is known about the main virulence factors of C. tropicalis, highlighting the missing pieces to stimulate further research with C. tropicalis and other non-Candida albicans species.