Balancing act: thiol-based redox regulation drives fungal pathogenesis

Cells must maintain an equilibrium between external and internal sources of oxidation while also employing endogenously generated reactive species to support intracellular signaling and proliferation. This balancing act is crucial for fungal pathogens, as their survival depends on the skillful coordination of attack and defense mechanisms to overcome stressors encountered in the hostile host environment. In this review, we examine recent findings on the contributions of small-molecule and protein thiols to fungal pathogenesis, and place this information in the context of the thiol-based redox systems that support the response to oxidative stress in fungal pathogens of humans. The emerging view is that small molecules and thiol-active proteins/enzymes maintain a redox balance during infection thereby avoiding irreversible oxidative damage and ultimately supporting fungal growth and pathogenesis.