Fungal iron-dependent respiratory pathways and ergosterol biosynthesis

Fungal iron-dependent respiratory pathways and ergosterol biosynthesis represent a critical metabolic network essential for the survival and virulence of pathogenic fungi, particularly under the iron-limited conditions of the human host. This network includes the mitochondrial electron transport chain (respiration) and the ergosterol biosynthetic pathway, both of which rely heavily on iron-containing cofactors such as heme and iron-sulfur clusters. The transcription factor HapX, in association with the CCAAT-binding complex (CBC), serves as the master regulator of these pathways, repressing them during iron starvation to prioritize iron for essential cellular functions. Therapeutic strategies targeting this network include the use of iron mimetics like gallium, which inactivates iron-dependent enzymes by replacing iron, and iron chelators that induce lethal iron deficiency. Because these pathways are vital for fungal growth and are distinct from human metabolic regulation in their response to iron stress, they are considered high-priority targets for the development of novel antifungal agents.

Other names

Iron-dependent metabolismHapX-regulated pathwaysFungal iron-consuming pathwaysIron-responsive metabolic network

Disruption of iron-dependent enzymatic activity through iron substitution by mimetics (e.g., Gallium) or iron depletion by chelators, and transcriptional regulation of these pathways by the HapX/CBC complex in response to iron availability.