Screening a fosmid library of Xenorhabdus stockiae HN_xs01 reveals SrfABC toxin that exhibits both cytotoxicity and injectable insecticidal activity
Screening a fosmid library of Xenorhabdus stockiae HN_xs01 reveals SrfABC toxin that exhibits both cytotoxicity and injectable insecticidal activity
复制标题
筛选 Xenorhabdus stockiae HN_xs01 的 fosmid 文库揭示了具有细胞毒性和注射杀虫活性的 SrfABC 毒素
DOI：
10.1016/j.jip.2019.107247
复制
发表时间：
2019
影响因子：
3.4
通讯作者：
Hu Shengbiao
中科院分区：
文献类型：
--
作者：
Yang Xi;Hou Xiaoqing;Sun Yawei;Zhang Guoyong;Hu Xiaofeng;Xie Yali;Mo Xiangtao;Ding Xuezhi;Xia Liqiu;Hu Shengbiao
Xenorhabdus spp. 是一种与斯坦线虫家族线虫共生的昆虫病原细菌，已知会产生几种干扰昆虫细胞免疫反应的有毒蛋白质。为了鉴定 Xenorhabdusspp. 中的新型细胞毒素，X 的 fosmid 文库。构建了stockiaeHN_xs01菌株，并测试了fosmid克隆对昆虫中肠CF-203细胞的细胞毒性。最初在肠沙门氏菌中鉴定出的带有 srfABC 操纵子的 FS2 克隆对 CF-203 细胞表现出优异的细胞毒性。 srfABC操纵子单独表现出细胞毒性作用，并且SrfABC毒素的所有三种成分对于完全细胞毒性都是必需的。免疫荧光研究表明，SrfABC 毒素可以解聚微管并破坏线粒体。流式细胞仪分析表明，SrfABC 毒素显着诱导 CF-203 细胞 G2/M 期停滞和凋亡。此外，SrfABC 毒素对棉铃虫幼虫表现出高度可注射杀虫活性。正如在宿主相关微生物中经常发现的那样，SrfABC 毒素被认为在宿主定植中发挥着重要作用。
Xenorhabdus spp., entomopathogenic bacteria symbiotically associated with the nematodes of the Steinernematid family, are known to produce several toxic proteins that interfere with the cellular immune responses of insects. In order to identify novel cytotoxins fromXenorhabdusspp., a fosmid library ofX. stockiaeHN_xs01 strain was constructed and the cytotoxicity of fosmid clones was tested against insect midgut CF-203 cells. An FS2 clone bearing thesrfABCoperon, originally identified inSalmonella enterica,exhibited excellent cytotoxicity against CF-203 cells. ThesrfABCoperon alone exhibited cytotoxic effects and all three components of SrfABC toxin were essential for full cytotoxicity. Immunofluorescence studies showed that SrfABC toxin could depolymerize microtubules and disrupt mitochrondria. Flow cytometer analysis demonstrated that SrfABC toxin significantly induced G2/M phase arrest and apoptosis in CF-203 cells. Furthermore, SrfABC toxin exhibits highly injectable insecticidal activity againstHelicoverpa armigeralarvae. As is often found in host-associated microorganisms, SrfABC toxin is thought to play an important role in host colonization.