Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
Mar Drugs. 2021 Apr 28;19(5):250. doi: 10.3390/md19050250.
Different shrimp species are known to possess apparent distinct resistance to different pathogens in aquaculture. However, the molecular mechanism underlying this finding still remains unknown. One kind of important antimicrobial peptides, anti-lipopolysaccharide factors (ALF), exhibit broad-spectrum antimicrobial activities. Here, we reported a newly identified ALF from the shrimp and compared the immune function with its counterpart in the shrimp . The ALF, designated as LvALF8, was specifically expressed in the lymphoid organ of . The expression level of was apparently changed after white spot syndrome virus (WSSV) or challenges. The synthetic LBD peptide of LvALF8 (LvALF8-LBD) showed strong antibacterial activities against most tested Gram-negative and Gram-positive bacteria. LvALF8-LBD could also inhibit the in vivo propagation of WSSV similar as FcALF8-LBD, the LBD of LvALF8 counterpart in . However, LvALF8-LBD and FcALF8-LBD exhibited apparently different antibacterial activity against , the main pathogen causing acute hepatopancreatic necrosis disease (AHPND) of affected shrimp. A structural analysis showed that the positive net charge and amphipathicity characteristics of LvALF8-LBD peptide were speculated as two important components for its enhanced antimicrobial activity compared to those of FcALF8-LBD. These new findings may not only provide some evidence to explain the distinct disease resistance among different shrimp species, but also lay out new research ground for the testing and development of LBD-originated antimicrobial peptides to control of shrimp diseases.
不同的虾类在水产养殖中对不同的病原体表现出明显不同的抗性。然而，这一发现的分子机制尚不清楚。一种重要的抗菌肽，抗脂多糖因子（ALF），具有广谱的抗菌活性。在这里，我们报道了一种从虾中鉴定出的新型 ALF，并与虾中的对应物进行了免疫功能比较。该 ALF 被命名为 LvALF8，特异性表达于虾的淋巴器官中。LvALF8 的表达水平在白斑综合征病毒（WSSV）或鳗弧菌挑战后明显改变。LvALF8 的合成 LBD 肽（LvALF8-LBD）对大多数测试的革兰氏阴性和革兰氏阳性菌均表现出强烈的抗菌活性。LvALF8-LBD 还可以像 FcALF8-LBD 一样抑制 WSSV 在体内的增殖，FcALF8-LBD 是 LvALF8 在 中的对应物的 LBD。然而，LvALF8-LBD 和 FcALF8-LBD 对 表现出明显不同的抗菌活性， 是导致受影响虾急性肝胰腺坏死病（AHPND）的主要病原体。结构分析表明，LvALF8-LBD 肽的正净电荷和两亲性特征被推测为其与 FcALF8-LBD 相比增强抗菌活性的两个重要组成部分。这些新发现不仅可能为解释不同虾类之间明显的疾病抗性提供一些证据，而且为测试和开发基于 LBD 的抗菌肽来控制虾病奠定了新的研究基础。
