Antifungal mechanism of a novel antifungal protein from pumpkin rinds against various fungal pathogens

J Agric Food Chem. 2009 Oct 14;57(19):9299-304. doi: 10.1021/jf902005g.

Abstract

A novel antifungal protein (Pr-2) was identified from pumpkin rinds using water-soluble extraction, ultrafiltration, cation exchange chromatography, and reverse-phase high-performance liquid chromatography. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry indicated that the protein had a molecular mass of 14865.57 Da. Automated Edman degradation showed that the N-terminal sequence of Pr-2 was QGIGVGDNDGKRGKR-. The Pr-2 protein strongly inhibited in vitro growth of Botrytis cinerea, Colletotrichum coccodes, Fusarium solani, Fusarium oxysporum, and Trichoderma harzianum at 10-20 microM. The results of confocal laser scanning microscopy and SYTOX Green uptake demonstrated that its effective region was the membrane of the fungal cell surface. In addition, this protein was found to be noncytotoxic and heat-stable. Taken together, the results of this study indicate that Pr-2 is a good candidate for use as a natural antifungal agent.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Botrytis / drug effects
  • Chromatography, High Pressure Liquid
  • Chromatography, Ion Exchange
  • Colletotrichum / drug effects
  • Cucurbita / chemistry*
  • Fungicides, Industrial / pharmacology*
  • Fusarium / drug effects
  • Hemolysis / drug effects
  • Humans
  • Microscopy, Confocal
  • Molecular Sequence Data
  • Plant Proteins / chemistry
  • Plant Proteins / isolation & purification
  • Plant Proteins / pharmacology*
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Trichoderma / drug effects

Substances

  • Fungicides, Industrial
  • Plant Proteins