Nontoxic antimicrobials that evade drug resistance

Nat Chem Biol. 2015 Jul;11(7):481-7. doi: 10.1038/nchembio.1821. Epub 2015 Jun 1.

Abstract

Drugs that act more promiscuously provide fewer routes for the emergence of resistant mutants. This benefit, however, often comes at the cost of serious off-target and dose-limiting toxicities. The classic example is the antifungal amphotericin B (AmB), which has evaded resistance for more than half a century. We report markedly less toxic amphotericins that nevertheless evade resistance. They are scalably accessed in just three steps from the natural product, and they bind their target (the fungal sterol ergosterol) with far greater selectivity than AmB. Hence, they are less toxic and far more effective in a mouse model of systemic candidiasis. To our surprise, exhaustive efforts to select for mutants resistant to these more selective compounds revealed that they are just as impervious to resistance as AmB. Thus, highly selective cytocidal action and the evasion of resistance are not mutually exclusive, suggesting practical routes to the discovery of less toxic, resistance-evasive therapies.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amphotericin B / analogs & derivatives
  • Amphotericin B / chemical synthesis*
  • Amphotericin B / pharmacology
  • Animals
  • Antifungal Agents / chemical synthesis*
  • Antifungal Agents / pharmacology
  • Binding Sites
  • Candida / chemistry
  • Candida / drug effects*
  • Candida / growth & development
  • Candida / pathogenicity
  • Candidiasis / drug therapy*
  • Candidiasis / microbiology
  • Candidiasis / mortality
  • Cell Line
  • Cell Survival / drug effects
  • Drug Resistance, Fungal / drug effects*
  • Epithelial Cells / cytology
  • Epithelial Cells / drug effects
  • Ergosterol / chemistry
  • Ergosterol / metabolism
  • Humans
  • Mice
  • Microbial Viability / drug effects
  • Structure-Activity Relationship
  • Survival Analysis
  • Urea / chemistry*

Substances

  • Antifungal Agents
  • Amphotericin B
  • Urea
  • Ergosterol

Supplementary concepts

  • Systemic candidiasis

Associated data

  • PubChem-Substance/250230390
  • PubChem-Substance/250230391
  • PubChem-Substance/250230392
  • PubChem-Substance/250230393