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bioRxiv · 10.64898/2026.04.12.718001

iCNG99: a validated genome-scale metabolic model of Cryptococcus neoformans strain H99

Abstract

Cryptococcus neoformans is a ubiquitous environmental fungus that can also cause life-threatening infections in immunocompromised individuals. As a competent pathogen, Cryptococcus needs to reprogram its metabolism to adapt to the drastic differences between environmental niches and host niches. A well-curated genome-scale metabolic model (GEM) is a powerful tool to facilitate the investigation of the metabolic resilience of an organism. Here we reconstructed and validated iCNG99, a GEM for C. neoformans reference strain H99, and evaluated its predictive performance across 43 growth conditions and gene essentiality benchmarks. The model achieved high confidence essential gene prediction (precision = 0.77) and recapitulated pathways targeted by clinically available antifungals. Integration with transcriptomic and metabolomic data enabled iCNG99 to capture condition-specific metabolic adaptations and to identify candidate vulnerabilities in drug tolerance, revealing metabolic adaptations associated with survival within host conditions and drug susceptibility. Together, iCNG99 provides a systems-level computational platform for investigating C. neoformans metabolism and for prioritizing antifungal vulnerabilities.

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Feng, C., Hu, P., Zhu, Y., Ke, W., Gao, X., Ding, C., Zhai, B., Wang, L., Dai, Z.. 2026-04-15. iCNG99: a validated genome-scale metabolic model of Cryptococcus neoformans strain H99. https://doi.org/10.64898/2026.04.12.718001

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