Wang Juanjuan, Bian Gang, Pan Wen, Feng Tingting, Dai Jianfeng
Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou City, Jiangsu Province, People's Republic of China.
Parasit Vectors. 2015 Jan 15;8:25. doi: 10.1186/s13071-014-0625-0.
Ticks are distributed worldwide and considered as vectors of many human diseases. Tick defensins, a family of antimicrobial peptides, form the first line of defense against pathogens.
A defensin-like gene, named Ds-defensin, was identified from a cDNA library of the hard tick Dermacentor silvarum collected from northeast China. The full-length cDNA of Ds-defensin was 225 bp, encoding a 74 amino acid peptide. The nucleotide sequence of Ds-defensin shared 98.2% similarity to putative defensin from Dermacentor marginatus. RT-PCR results suggested that Ds-defensin was extensively expressed in tick salivary gland and midgut, with a higher expression level in midgut. Ds-defensin showed broad antimicrobial activity against various Gram-positive and Gram-negative bacteria, as well as the fungus Candida albicans.
We characterized a functional defensin from D. silvarum of China. Ds-defensin showed bactericidal activity against various Gram-positive and Gram-negative bacteria. Ds-defensin can be expected to be introduced to the medical field as a new molecule with antibacterial activity.
蜱虫分布于全球，被认为是多种人类疾病的传播媒介。蜱虫防御素是一类抗菌肽，构成了抵御病原体的第一道防线。
从中国东北地区采集的森林革蜱的cDNA文库中鉴定出一个类似防御素的基因，命名为Ds-防御素。Ds-防御素的全长cDNA为225 bp，编码一个74个氨基酸的肽。Ds-防御素的核苷酸序列与边缘革蜱假定防御素的相似性为98.2%。逆转录聚合酶链反应结果表明，Ds-防御素在蜱虫唾液腺和中肠中广泛表达，在中肠中的表达水平更高。Ds-防御素对各种革兰氏阳性菌和革兰氏阴性菌以及白色念珠菌显示出广泛的抗菌活性。
我们鉴定了来自中国森林革蜱的一种功能性防御素。Ds-防御素对各种革兰氏阳性菌和革兰氏阴性菌具有杀菌活性。Ds-防御素有望作为一种具有抗菌活性的新分子被引入医学领域。
