Lee Y S, Yun E K, Jang W S, Kim I, Lee J H, Park S Y, Ryu K S, Seo S J, Kim C H, Lee I H
Department of Life Science, Hoseo University, South Korea.
Insect Mol Biol. 2004 Feb;13(1):65-72. doi: 10.1111/j.1365-2583.2004.00462.x.
An insect defensin, named Galleria defensin, was purified from the larval haemolymph of Galleria mellonella immunized against E. coli. The peptide was composed of forty-three amino acid residues containing six cysteines that might be engaged in intramolecular disulphide bridges. The primary structure of Galleria defensin shared about 90.7% identity to that of heliomicin, which was an insect defensin isolated from Heliothis virescens. The full-length cDNA encoding Galleria defensin was cloned from the fat body of the immunized G. mellonella larvae. Northern blot analysis revealed that Galleria defensin was expressed not only in the fat body but also in the midgut against invading bacteria into haemocoel. This is the first report presenting cDNA and expression of an insect defensin in the lepidopteran species.
从经大肠杆菌免疫的大蜡螟幼虫血淋巴中纯化出一种昆虫防御素，命名为大蜡螟防御素。该肽由43个氨基酸残基组成，含有6个半胱氨酸，这些半胱氨酸可能参与分子内二硫键的形成。大蜡螟防御素的一级结构与从烟芽夜蛾中分离出的昆虫防御素heliomicin的一级结构具有约90.7%的同源性。从经免疫的大蜡螟幼虫脂肪体中克隆出编码大蜡螟防御素的全长cDNA。Northern印迹分析表明，大蜡螟防御素不仅在脂肪体中表达，在中肠中也有表达，以抵御侵入血腔的细菌。这是关于鳞翅目昆虫防御素cDNA及其表达的首次报道。
