title: The Toxicity of a Novel Antifungal Compound Is Modulated by Endoplasmic Reticulum-Associated Protein Degradation Components.
abstract: In a search for new antifungal compounds, we screened a library of 4,454 chemicals for toxicity against the human fungal pathogen Aspergillus fumigatus. We identified sr7575, a molecule that inhibits growth of the evolutionary distant fungi A. fumigatus, Cryptococcus neoformans, Candida albicans, and Saccharomyces cerevisiae but lacks acute toxicity for mammalian cells. To gain insight into the mode of inhibition, sr7575 was screened against 4,885 S. cerevisiae mutants from the systematic collection of haploid deletion strains and 977 barcoded haploid DAmP (decreased abundance by mRNA perturbation) strains in which the function of essential genes was perturbed by the introduction of a drug resistance cassette downstream of the coding sequence region. Comparisons with previously published chemogenomic screens revealed that the set of mutants conferring sensitivity to sr7575 was strikingly narrow, affecting components of the endoplasmic reticulum-associated protein degradation (ERAD) stress response and the ER membrane protein complex (EMC). ERAD-deficient mutants were hypersensitive to sr7575 in both S. cerevisiae and A. fumigatus, indicating a conserved mechanism of growth inhibition between yeast and filamentous fungi. Although the unfolded protein response (UPR) is linked to ERAD regulation, sr7575 did not trigger the UPR in A. fumigatus and UPR mutants showed no enhanced sensitivity to the compound. The data from this chemogenomic analysis demonstrate that sr7575 exerts its antifungal activity by disrupting ER protein quality control in a manner that requires ERAD intervention but bypasses the need for the canonical UPR. ER protein quality control is thus a specific vulnerability of fungal organisms that might be exploited for antifungal drug development.
authors.affiliation: Institut Pasteur, Unité des Aspergillus, Département Mycologie, Paris, France.
authors.forename: Shriya
authors.initials: S
authors.lastname: Raj
authors.affiliation: Department of Pathology & Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio, USA.
authors.forename: Karthik
authors.initials: K
authors.lastname: Krishnan
authors.affiliation: Department of Pathology & Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio, USA.
authors.forename: David S
authors.initials: DS
authors.lastname: Askew
authors.affiliation: Institut Pasteur, Unité de Chimie et Biocatalyse, Département de Biologie Structurale et Chimie, Paris, France CNRS UMR3523, Paris, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Helynck
authors.affiliation: Centre d'Etudes et de Recherche sur le Médicament de Normandie, EA4258, UFR des Sciences Pharmaceutiques, University of Caen Basse-Normandie, Caen, France.
authors.forename: Peggy
authors.initials: P
authors.lastname: Suzanne
authors.affiliation: Centre d'Etudes et de Recherche sur le Médicament de Normandie, EA4258, UFR des Sciences Pharmaceutiques, University of Caen Basse-Normandie, Caen, France.
authors.forename: Aurélien
authors.initials: A
authors.lastname: Lesnard
authors.affiliation: Centre d'Etudes et de Recherche sur le Médicament de Normandie, EA4258, UFR des Sciences Pharmaceutiques, University of Caen Basse-Normandie, Caen, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Rault
authors.affiliation: Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Mycologie, Paris, France INRA USC2019, Paris, France.
authors.forename: Ute
authors.initials: U
authors.lastname: Zeidler
authors.affiliation: Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Mycologie, Paris, France INRA USC2019, Paris, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: d'Enfert
authors.affiliation: Institut Pasteur, Unité des Aspergillus, Département Mycologie, Paris, France jean-paul.latge@pasteur.fr helene.munier-lehmann@pasteur.fr cosmin.saveanu@pasteur.fr.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Latgé
authors.affiliation: Institut Pasteur, Unité de Chimie et Biocatalyse, Département de Biologie Structurale et Chimie, Paris, France CNRS UMR3523, Paris, France jean-paul.latge@pasteur.fr helene.munier-lehmann@pasteur.fr cosmin.saveanu@pasteur.fr.
authors.forename: Hélène
authors.initials: H
authors.lastname: Munier-Lehmann
authors.affiliation: Institut Pasteur, Unité de Génétique des Interactions Macromoléculaires, Département Génomes et Génétique, Paris, France CNRS UMR3525, Paris, France jean-paul.latge@pasteur.fr helene.munier-lehmann@pasteur.fr cosmin.saveanu@pasteur.fr.
authors.forename: Cosmin
authors.initials: C
authors.lastname: Saveanu
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology* / Q000633:toxicity*; D001232:Aspergillus fumigatus / Q000187:drug effects* / Q000235:genetics; D002176:Candida albicans / Q000187:drug effects; D003455:Cryptococcus neoformans / Q000187:drug effects; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D060746:Endoplasmic Reticulum-Associated Degradation / Q000187:drug effects* / Q000235:genetics; D006367:HeLa Cells / Q000187:drug effects; D006801:Humans; D008815:Mice, Inbred Strains; D008826:Microbial Sensitivity Tests; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics; D054852:Small Molecule Libraries / Q000494:pharmacology; D056811:Unfolded Protein Response / Q000187:drug effects
chemical_list: D000935:Antifungal Agents; D054852:Small Molecule Libraries