The natural diyne-furan fatty acid EV-086 is an inhibitor of fungal delta-9 fatty acid desaturation with efficacy in a model of skin dermatophytosis

Antimicrob Agents Chemother. 2014;58(1):455-66. doi: 10.1128/AAC.01443-13. Epub 2013 Nov 4.

Abstract

Human fungal infections represent a therapeutic challenge. Although effective strategies for treatment are available, resistance is spreading, and many therapies have unacceptable side effects. A clear need for novel antifungal targets and molecules is thus emerging. Here, we present the identification and characterization of the plant-derived diyne-furan fatty acid EV-086 as a novel antifungal compound. EV-086 has potent and broad-spectrum activity in vitro against Candida, Aspergillus, and Trichophyton spp., whereas activities against bacteria and human cell lines are very low. Chemical-genetic profiling of Saccharomyces cerevisiae deletion mutants identified lipid metabolic processes and organelle organization and biogenesis as targets of EV-086. Pathway modeling suggested that EV-086 inhibits delta-9 fatty acid desaturation, an essential process in S. cerevisiae, depending on the delta-9 fatty acid desaturase OLE1. Delta-9 unsaturated fatty acids-but not saturated fatty acids-antagonized the EV-086-mediated growth inhibition, and transcription of the OLE1 gene was strongly upregulated in the presence of EV-086. EV-086 increased the ratio of saturated to unsaturated free fatty acids and phosphatidylethanolamine fatty acyl chains, respectively. Furthermore, EV-086 was rapidly taken up into the lipid fraction of the cell and incorporated into phospholipids. Together, these findings demonstrate that EV-086 is an inhibitor of delta-9 fatty acid desaturation and that the mechanism of inhibition might involve an EV-086-phospholipid. Finally, EV-086 showed efficacy in a guinea pig skin dermatophytosis model of topical Trichophyton infection, which demonstrates that delta-9 fatty acid desaturation is a valid antifungal target, at least for dermatophytoses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antifungal Agents / therapeutic use*
  • Fatty Acid Desaturases / antagonists & inhibitors*
  • Gene Expression Regulation, Enzymologic
  • Gene Expression Regulation, Fungal / drug effects
  • Guinea Pigs
  • Stearoyl-CoA Desaturase
  • Tinea / drug therapy*

Substances

  • Antifungal Agents
  • Fatty Acid Desaturases
  • Stearoyl-CoA Desaturase
  • delta-9 fatty acid desaturase