XaxAB-like binary toxin from Photorhabdus luminescens exhibits both insecticidal activity and cytotoxicity.
XaxAB-like binary toxin from Photorhabdus luminescens exhibits both insecticidal activity and cytotoxicity.
复制标题
来自发光杆菌的 XaxAB 样二元毒素具有杀虫活性和细胞毒性。
DOI：
10.1111/1574-6968.12321
复制
发表时间：
2014
影响因子：
2.1
通讯作者：
Shengbiao Hu
中科院分区：
文献类型：
--
作者：
Xu Zhang;Xiaofeng Hu;Yusheng Li;Xuezhi Ding;Qi Yang;Yunjun Sun;Ziquan Yu;L. Xia;Shengbiao Hu
发光肠杆菌产生多种毒素来杀死其昆虫宿主。通过分析P. luminescens TT01的基因组序列，我们发现plu1961和plu1962编码的氨基酸序列与Xenorhabuds nematophila的XaxAB二元毒素高度相似，该毒素在体外对昆虫和哺乳动物细胞均具有坏死和凋亡活性。为了评估Plu1961/Plu1962的生物活性，克隆了它们的编码基因并在大肠杆菌中表达。 Plu1961 和 Plu1962 均在 BL21 (DE3) 中表达为可溶性蛋白，它们的混合物导致昆虫中肠 CF-203 细胞通过坏死而死亡。共焦荧光显微镜显示，Plu1961/Plu1962 混合物能够解聚微管并诱导 CF-203 细胞质膜通透性增加。此外，Plu1961/Plu1962在同一细胞质中的共表达对哺乳动物细胞（B16、4T1和HeLa细胞）表现出细胞毒性作用，并对甜菜夜蛾幼虫表现出可注射活性。到目前为止，已在发光假单胞菌中鉴定出两种类型的二元毒素，第一种是PirAB，第二种是Plu1961/Plu1962。 Plu1961/Plu1962二元毒素在感染过程中发挥的生物学作用值得今后引起更多关注。
The enterobacterium Photorhabdus luminescens produces a number of toxins to kill its insect host. By analyzing the genomic sequence of P. luminescens TT01, we found that amino acid sequences encoded by plu1961 and plu1962 showed high similarity to XaxAB binary toxin of Xenorhabuds nematophila, which has both necrotic and apoptotic activities in both insect and mammalian cells in vitro. To evaluate the biological activity of Plu1961/Plu1962, their coding genes were cloned and expressed in Escherichia coli. Both Plu1961 and Plu1962 were expressed as soluble protein in BL21 (DE3) and their mixture caused insect midgut CF-203 cells death via necrosis. Confocal fluorescence microscopy showed that Plu1961/Plu1962 mixture was able to depolymerize microtubule and induce the increase in plasma membrane permeabilization in CF-203 cells. Moreover, co-expression of Plu1961/Plu1962 in the same cytoplasm exhibited cytotoxic effect against mammalian cells (B16, 4T1, and HeLa cells) and injectable activity against Spodoptera exigua larvae. Until now, two types of binary toxins have been identified in P. luminescens, the first type is PirAB and Plu1961/Plu1962 is the second one. The biological role of Plu1961/Plu1962 binary toxin played in the infection process should attract more attention in future.