Page 32 - Rappaport Institute Magazine 2024

MOLECULAR MICROBIOLOGY
Daniel Kornitzer, PhD Professor of Microbiology
PhD, 1991 – The Hebrew University of Jerusalem, Israel
Virulence factors of the common fungal pathogen
Candida albicans
Pathogenic microbes have evolved a large array of adaptations that allow them to survive and proliferate in the human host environment. The laboratory is focusing on Candida albicans, a commensal organism of human epithelia that also constitutes the most common systemic fungal pathogen. Systemic Candida infections are increasingly prevalent among immunosuppressed patients. While investigating its ability to extract iron from host proteins, we have identified a network of specialized Candida cell surface heme-binding proteins that capture heme from the host and transfer it across the cell wall to the cell membrane. A new class of transmembrane proteins mediate internalization and utilization of host heme. We anticipate that molecular understanding of the factors required for Candida albicans virulence will ultimately lead to new ways to combat fungal infection.
Selected Publications
ˆ Roy, U. et al., eLife 80604 (2022) Ferric reductase-related proteins mediate fungal heme acquisition
ˆ Andrawes, N. et al., PLOS Genetics 18: e1010390 (2022) Regulation of heme utilization and homeostasis in Candida albicans
ˆ Nasser, L. et al., Nature Microbiology 1:16156 (2016) Structural basis of haem-iron acquisition by fungal pathogens
ˆ Kuznets, G. et al., PLOS Pathogens 10(10): e1004407 (2014) A relay network of extracellular heme-binding proteins drives C. albicans iron acquisition from hemoglobin
Grants and Awards
Israel Science Foundation
ISF-NRF (Singapore) joint program US-Israel Binational Science Foundation Italy-Israel Ministry of Science collaboration
danielk@technion.ac.il
Daniel Kornitzer Lab
Frp1 is a membrane protein that is necessary for internalization of host heme into the cell. GFP-tagged Frp1 is localized mainly in the endoplasmic reticulum and the vacuole in the absence of heme in
the environment (left), but relocalizes to the plasma membrane within 10 min of exposure to heme (right).