Amphibian cathelicidin fills the evolutionary gap of cathelicidin in vertebrate
Amphibian cathelicidin fills the evolutionary gap of cathelicidin in vertebrate
复制标题
两栖动物抗菌素填补了脊椎动物抗菌素的进化空白
DOI：
10.1007/s00726-011-1116-7
复制
发表时间：
2012-08-01
期刊：
影响因子：
3.5
通讯作者：
Lai, Ren
中科院分区：
文献类型：
--
作者：
Hao, Xue;Yang, Hailong;Lai, Ren
Cathelicidins是一类具有高度保守的cathelin结构域的抗菌肽家族，在大多数脊椎动物的先天性抗感染防御中发挥重要作用。但到目前为止，它还没有被发现在两栖动物，虽然大量的其他组的AMP已被确定。本工作首次从罗罗湍蛙（Amolops loloensis）蛙皮中分离到一种抗菌肽（cathelicidin-AL）。Cathelicidin-AL（RRSRRGRGGGRRGGSGGRGRGGGRSGAGSSIAGVGSRGGGGGRHYA）是一种阳离子肽，含有48个氨基酸残基（aa），其中12个是碱性氨基酸，没有酸性氨基酸。化学合成的肽有效地杀死细菌和一些真菌物种，包括临床分离的耐药微生物。从A.洛洛人。与其他cathelicidin一样，cathelicidin-AL的前体也含有高度保守的半胱氨酸蛋白酶抑制剂的阴离子cathelin结构域，随后是C-末端的AMP片段。系统发育分析表明，作为连接环节，两栖类cathelicidin早于爬行类，但晚于鱼类cathelicidin。肽段纯化结合基因克隆的结果证实了cathelicidin在两栖动物中的存在，填补了cathelicidin在脊椎动物中的进化空白，认为两栖动物的特殊生态位是连接陆地-水域进化空白的桥梁。
Cathelicidins comprise a family of antimicrobial peptides (AMPs) sharing a highly conserved cathelin domain, and play a central role in the innate defense against infection in most of vertebrates. But so far it has not yet been found in amphibians although a large number of other groups of AMPs have been identified. In the current work, the first amphibian cathelicidin (cathelicidin-AL) has been characterized from the frog skin ofAmolops loloensis. Cathelicidin-AL (RRSRRGRGGGRRGGSGGRGGRGGGGRSGAGSSIAGVGSRGGGGGRHYA) is a cationic peptide containing 48 amino acid residues (aa) with 12 basic aa and no acidic aa. The chemical synthesized peptide efficiently killed bacteria and some fungal species including clinically isolated drug-resistance microorganisms. The cDNA encoding cathelicidin-AL precursor was cloned from the skin cDNA library ofA. loloensis. As other cathelicidins, the precursor of cathelicidin-AL also contains highly conserved anionic cathelin domain of cysteine proteinase inhibitor followed by the AMP fragment at C-terminus. Phylogenetic analysis revealed that as connecting link, the amphibian cathelicidin predates reptilia but postdates fish cathelicidin. The peptide purification combined with gene cloning results confirms the presence of cathelicidin in amphibians and filled the evolutionary gap of cathelicidin in vertebrate, considering amphibians’ special niche as the animals bridging the evolutionary land-water gap.