Correspondence

Plants are able to produce compounds that act as nat-ural defences against pests and pathogens [1,2]. Among known plant protection compounds are the low molecu-lar mass substances polyanions and monosaccharides, and many different proteins with antimicrobial activit-ies. These include chitinases, glucanases, lipid transfer proteins, chitin-binding lectins, digestive enzyme inhibi-tors and c-thionins, also known as plant defensins [3]. c-Thionins are proteins of about 5.0 kDa, which are found in different tissues of many plant species [4,5]. These proteins belong to a family of small proteins, usu-ally 45–54 amino acids long, which include eight half-cystines, with antibiotic properties [6,7]. c-Thionins can occur in seed endosperm, stems, roots and etiolated or pathogen-stressed leaves in many plant species [8]