A novel killer toxin produced by the marine-derived yeast Wickerhamomyces anomalus YF07b

Antonie Van Leeuwenhoek. 2013 Apr;103(4):737-46. doi: 10.1007/s10482-012-9855-3. Epub 2012 Nov 20.

Abstract

In our previous study, it was found that the killer toxin produced by the marine-derived yeast Wickerhamomyces anomalus YF07b has both killing activity and β-1,3-glucanase activity and the molecular mass of it is 47.0 kDa. In this study, the same yeast strain was found to produce another killer toxin which only had killing activity against some yeast strains, but had no β-1,3-glucanase activity and the molecular mass of the purified killer toxin was 67.0 kDa. The optimal pH, temperature and NaCl concentration for action of the purified killer toxin were 3.5, 16 °C and 4.0 % (w/v), respectively. The purified killer toxin could be bound by the whole sensitive yeast cells, but was not bound by manann, chitin and β-1,3-glucan. The purified killer toxin had killing activity against Yarrowia lipolytica, Saccharomyces cerevisiae, Metschnikowia bicuspidata WCY, Candida tropicalis, Candida albicans and Kluyveromyces aestuartii. Lethality of the sensitive cells treated by the newly purified killer toxin from W. anomalus YF07b involved disruption of cellular integrity by permeabilizing cytoplasmic membrane function.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Membrane / drug effects
  • Cell Membrane / physiology
  • Cell Membrane / ultrastructure
  • Hydrogen-Ion Concentration
  • Killer Factors, Yeast / chemistry
  • Killer Factors, Yeast / metabolism*
  • Microbial Viability / drug effects
  • Microscopy, Electron, Scanning
  • Molecular Weight
  • Protein Stability
  • Saccharomycetales / isolation & purification*
  • Saccharomycetales / metabolism*
  • Temperature
  • Yeasts / drug effects
  • Yeasts / physiology
  • Yeasts / ultrastructure

Substances

  • Killer Factors, Yeast