Yang Jing, Chen Yun-Ze, Zhang Guo-Cai
College of Forestry, Guizhou University, Guiyang, China.
College of Forestry, Northeast Forestry University, Harbin, China.
Front Microbiol. 2024 Sep 18;15:1417598. doi: 10.3389/fmicb.2024.1417598. eCollection 2024.
The gut bacteria of insects play an important role in regulating their metabolism, immune system and metabolizing pesticides. Our previous results indicate that carvacrol has certain gastric toxic activity on larvae and affects their detoxification metabolism at the mRNA level. However, the impact of carvacrol on the gut bacteria of larvae has been unclear.
In this study, the 16S rRNA sequencing technology was used to sequence and analyze the gut bacteria of the larvae which were exposed with sublethal concentration (0.297 mg/mL) and median lethal concentration (1.120 mg/mL), respectively.
A total of 10 phyla, 16 classes, 47 orders, 72 families, 103 genera, and 135 species were obtained by using a 97% similarity cutoff level. The dominant bacterial phyla in the gut of the larvae are and . The treatment with carvacrol can significantly affect the structure of gut bacteria in the larvae of the . At both doses, carvacrol can shift the dominant gut bacteria of the larvae from to . At the genus level, two doses of carvacrol can significantly enhance the relative abundance of probiotic in the gut of larvae ( ≤ 0.01). Additionally, significant differences were observed among the five bacterial genera , , , ( ≤ 0.05). The analysis of -diversity and -diversity indicates that the treatment with carvacrol at two doses significantly affect the bacterial richness and diversity in the larvae. However, the results of functional classification prediction (PICRUSt) indicate that carvacrol significantly down-regulate 7 functions, including Energy metabolism, Cell growth and death, and up-regulate 2 functions, including Carbohydrate metabolism and Membrane transport. The network analysis indicates that the correlation between gut bacteria also has been changed. In addition, the insecticidal activity results of carvacrol against larvae with gut bacteria elimination showed that gut bacteria can reduce the insecticidal activity of carvacrol against larvae.
This study provides a theoretical foundation for understanding the role of gut bacteria in detoxifying plant toxins and conferring pesticide resistance.
昆虫的肠道细菌在调节其新陈代谢、免疫系统和农药代谢方面发挥着重要作用。我们之前的结果表明，香芹酚对幼虫具有一定的胃毒活性，并在mRNA水平上影响其解毒代谢。然而，香芹酚对幼虫肠道细菌的影响尚不清楚。
在本研究中，采用16S rRNA测序技术对分别暴露于亚致死浓度（0.297mg/mL）和半数致死浓度（1.120mg/mL）的幼虫肠道细菌进行测序和分析。
使用97%相似性截断水平共获得10个门、16个纲、47个目、72个科、103个属和135个物种。幼虫肠道中的优势细菌门是 和 。香芹酚处理可显著影响 幼虫肠道细菌的结构。在两种剂量下，香芹酚均可使幼虫的优势肠道细菌从 转变为 。在属水平上，两种剂量的香芹酚均可显著提高 幼虫肠道中益生菌 的相对丰度（ ≤0.01）。此外，在五个细菌属 、 、 、 之间观察到显著差异（ ≤0.05）。α多样性和β多样性分析表明，两种剂量的香芹酚处理均显著影响幼虫中的细菌丰富度和多样性。然而，功能分类预测（PICRUSt）结果表明，香芹酚显著下调了7种功能，包括能量代谢、细胞生长和死亡，并上调了2种功能，包括碳水化合物代谢和膜转运。网络分析表明肠道细菌之间的相关性也发生了变化。此外，香芹酚对消除肠道细菌的 幼虫的杀虫活性结果表明，肠道细菌可降低香芹酚对 幼虫的杀虫活性。
本研究为理解肠道细菌在解毒植物毒素和赋予抗药性方面的作用提供了理论基础。
