Novel antifungal defensins from Nigella sativa L. seeds

From seeds of Nigella sativa L. (Ranunculaceae), an endemic plant of Uzbekistan, two novel defensins named Ns-D1 and Ns-D2, were isolated and sequenced. The peptides differ by a single amino acid residue and show high sequence similarity to Raphanus sativus L. defensins Rs-AFP1 and Rs-AFP2. The Ns-D1 and Ns-D2 defensins display strong although divergent antifungal activity towards a number of phytopathogenic fungi. High antifungal activity of N. sativa defensins makes them promising candidates for engineering pathogen-resistant plants.

Research highlights
► In this study we isolated and characterized two novel antimicrobial peptides from seeds of Nigella sativa (blackseed), an endemic plant of Uzbekistan.
► We showed these peptides differed by a single amino acid residue and show high sequence similarity to Raphanus sativus L. defensins.
► The blackseed defensins display strong although divergent antifungal activity towards a number of phytopathogenic fungi and oomycete-Phytophthora infestans.
► In this study we conclude high antifungal activity of Nigella sativa defensins makes them promising candidates for engineering pathogen-resistant plants.