Isolation of the lipid-transporting protein Ns-LTP1 from seeds of the garden fennel flower (Nigella sativa)

Abstract

A novel lipid-transporting protein (Ns-LTP1) has been isolated from seeds of the garden fennel flower Nigella sativa. The molecular mass, N-terminal amino acid sequence, and amino acid composition of the protein have been determined. Ns-LTP1 has a molecular mass of 9602 Da and contains eight cysteine residues which form four disulfide bridges. The protein is capable of suppressing the development of some phytopathogenic fungi and oomycetes.

Interaction of lipid-transport proteins from Nigella sativa seeds with lipid membranes

“…They can inhibit in vivo the growth of bacteria and fungi [8]. One of the proposed mechanisms of the antifungal activity of several LTPs (Ha-AP10 from Helianthus annuus [9], LTP2 from wheat [10], and LTP from onion [11]) is the induction by them of increased permeability of pathogen plasmatic membranes for small organic molecules and inorganic ions.It would be useful to find trends in their effects on the structural properties of lipid membranes in order to understand better differences in the effectiveness with which LTP from various sources interact with lipids.Our goal was to study the effects of three LTP isolated from Nigella sativa seeds (Ns-LTPs) that had different physicochemical properties (LTP1, LTP2, LTP3) on the permeability of model lipid membranes.We have previously isolated and studied the physicochemical properties of Ns-LTP1 from N. sativa seeds [12]. Here we continued the detailed investigation of the peptide composition from N. sativa seeds and found two more peptides that belonged to the same class as LTP1 but had different molecular weights (MWs).…”

Bioactive peptides from several plant species

“…Peptides with molecular weight (MW) 2-10 kDa were found. According to the literature and our results [7,8], it can be assumed that peptides with MW 2-5 kDa belong to the defensin class; with MW ~10 kDa, to the so-called lipid-transfer proteins.The biological activity of the seed extracts and fractions obtained after separation over CM-TSK gel was checked in tests for fungitoxicity using a culture of pathogenic strains No. 108 Verticillium dahliae and a turbidimetric microplanchette method [9]; for cytotoxicity, KML murine melanoma cells in tissue culture and measurement of 3 H-thymidine incorporation into tumor cell DNA [10] (Table 1).…”

“…Peptides with molecular weight (MW) 2-10 kDa were found. According to the literature and our results [7,8], it can be assumed that peptides with MW 2-5 kDa belong to the defensin class; with MW ~10 kDa, to the so-called lipid-transfer proteins.…”

Isolation of cysteine-rich peptides from Nigella sativa sprouts

“…Our goal was to develop methods for preparative isolation of AMP from two-week sprouts of Nigella sativa L. We have previously performed analytical separation of total extracts from seeds and sprouts [5] and isolated and characterized a lipid-transfer protein from seeds [6].…”

“…The study of antimicrobial peptides (AMP) has fundamental significance for explaining the molecular mechanisms of the acquired immunity of plants and is of great practical interest for developing a new strategy for battling pathogens and agricultural pests that is based on genetic engineering methods. The search for AMP from new plant sources is just as promising for developing a new generation of drugs and preservatives for the food industry.Our goal was to develop methods for preparative isolation of AMP from two-week sprouts of Nigella sativa L. We have previously performed analytical separation of total extracts from seeds and sprouts [5] and isolated and characterized a lipid-transfer protein from seeds [6].Acid extraction followed by three-step chromatography was used to isolate AMP from N. sativa sprouts. Two main fractions that eluted at different NaCl concentrations (100 and 500 mM) were obtained from Hi Trap Heparin HP affinity sorbent.…”