Yu Haining, Yang Hailong, Ma Dongying, Lv Yi, Liu Tongguang, Zhang Keyun, Lai Ren, Liu Jingze
College of Life Sciences School of Hebei Normal University, Shijiazhuang, Hebei 050016, China.
Toxicon. 2007 Sep 1;50(3):377-82. doi: 10.1016/j.toxicon.2007.04.023. Epub 2007 May 10.
Despite the evolutional distance between wasp and amphibian, vespid chemotactic peptide (VCP), an important component of wasp venom, are found sharing remarkable similarities with the temporin antimicrobial peptides (AMPs) from Ranid frog, Amolops loloensis. Not only their amino acid sequences are highly similar, but they are both microbe-killing and can induce the cellular chemotactic response. However, whether the two peptides possess identical biosynthesis pathway was still not clear due to the unsolved gene sequence of VCP putative precursor. In this paper, a cDNA encoding one of VCP precursors was cloned from the venom sac cDNA library of the wasp, Vespa magnifica (Smith), and the corresponding native VCP was purified from the venoms. It was shown that the VCP precursor highly resembled temporin precursor not only in the sequence size but also in the sequences of their corresponding mature peptides. However, the enzyme-cutting sites and the possible processing enzymes for both peptides were different, which for VCP were dipeptidyl peptidase IV and trypsin-like proteases, while for temporin were only trypsin-like protease. The current results suggested that the biosynthesis mode of VCP was different from that of temporin AMP, even though the two mature peptides were similar in many ways. It is also the first report about VCP precursor from wasp venom.
尽管黄蜂与两栖动物在进化上相距甚远,但黄蜂毒液的重要成分黄蜂趋化肽(VCP)却与蛙科蛙属、洛洛掌突蟾的颞叶抗菌肽(AMPs)有着显著的相似性。它们不仅氨基酸序列高度相似,而且都具有杀灭微生物的能力,并能诱导细胞趋化反应。然而,由于VCP假定前体的基因序列尚未解决,这两种肽是否具有相同的生物合成途径仍不清楚。在本文中,从黄蜂(金环胡蜂,史密斯)的毒囊cDNA文库中克隆了一个编码VCP前体之一的cDNA,并从毒液中纯化出了相应的天然VCP。结果表明,VCP前体不仅在序列大小上,而且在其相应成熟肽的序列上都与颞叶抗菌肽前体高度相似。然而,这两种肽的酶切位点和可能的加工酶不同,VCP的是二肽基肽酶IV和类胰蛋白酶,而颞叶抗菌肽的只有类胰蛋白酶。目前的结果表明,尽管这两种成熟肽在许多方面相似,但VCP的生物合成模式与颞叶抗菌肽不同。这也是关于黄蜂毒液中VCP前体的首次报道。