Malting barley grain non-specific lipid-transfer protein (ns-LTP): Importance for grain protection

Abstract

A basic protein (pI < 9) was isolated to homogeneity from a domestic cultivar of malting barley grain (Hordeum vulgare). In its unreduced form it exists as a dimer of a 9 kDa protomer with four disulphide bridges. These characteristics together with protein sequence data revealed that the isolated protein belongs to the class of ns-LTP. The antifungal potency of malting barley grain ns-LTP was examined on Saccharomyces cerevisiae, Candida albicans and the plant pathogen Fusarium solani growth in vitro. It was found that ns-LTP inhibits Saccharomyces and Fusarium growth; the concentration required for 50% inhibition after 24 h of incubation (IC50) was 100 and 80 μg/mL, respectively. On the basis of these results, the importance of ns-LTP for barley grain protection from fungal diseases has been discussed. © 2005 The Institute of Brewing & Distilling.