Laboratory of Molecular Biology, Institute of Biological Sciences, Federal University of Rio Grande-FURG, Av. Italia Km 8, Rio Grande, RS, CEP 96203-900, Brazil.
Laboratory of Parasitic Immunology, Institute of Biology, Federal University of Pelotas-UFPel, Pelotas, Brazil.
Curr Microbiol. 2023 Mar 14;80(5):136. doi: 10.1007/s00284-023-03240-0.
It is known that probiotic microorganisms play important roles in the composition of the intestinal microbiota. Also, probiotics can affect the paracellular and transcellular transport mechanisms performed by intestinal cells. The aim of this work was to evaluate the effect of the potential probiotic Bacillus subtilis KM0 on the profile of the gut microbiota and transcription of genes related to intestinal transport of zebrafish (Danio rerio). Zebrafish was exposed by immersion to B. subtilis KM0 for 48 h, and the intestines were collected for metataxonomic analysis and transcription of genes related to transcellular and paracellular transports. Although exposure to B. subtilis changed the intestinal microbiota profile of zebrafish, the diversity indices were not altered. A decrease in the number of genera of potentially pathogenic bacteria (Flavobacterium, Plesiomonas, and Pseudomonas) and downregulation in transcription of transcellular transport genes (cubn and amn) were observed. B. subtilis KM0 strain had the expected probiotic effect, by interfering with the proliferation of potentially pathogenic bacteria and decreasing the transcription of genes codifying for signals involved with a mechanism that can be used for invasion by pathogens. The present study demonstrated that, even with a short-term exposure, a bacterium with probiotic potential such as the KM0 strain of B. subtilis can modify the profile of the host's intestinal microbiota, with an impact on the regulation of intestinal genes related to mechanisms that can be used for invasion by pathogenic bacteria.
已知益生菌微生物在肠道微生物群的组成中发挥着重要作用。此外，益生菌可以影响肠道细胞进行的细胞旁和细胞内转运机制。本工作的目的是评估潜在益生菌枯草芽孢杆菌 KM0 对斑马鱼（Danio rerio）肠道微生物群谱和与肠道转运相关基因转录的影响。斑马鱼通过浸泡暴露于枯草芽孢杆菌 KM0 48 小时，收集肠道进行分类群分析和与细胞内和细胞旁转运相关基因的转录。尽管枯草芽孢杆菌 KM0 的暴露改变了斑马鱼的肠道微生物群谱，但多样性指数没有改变。观察到潜在致病性细菌（黄杆菌属、气单胞菌属和假单胞菌属）的属数量减少，以及细胞内转运基因（cubn 和 amn）的转录下调。枯草芽孢杆菌 KM0 菌株具有预期的益生菌作用，通过干扰潜在致病性细菌的增殖和降低编码与病原体入侵机制相关信号的基因的转录来实现。本研究表明，即使是短期暴露，具有益生菌潜力的细菌，如枯草芽孢杆菌 KM0 菌株，也可以改变宿主肠道微生物群的谱，从而影响与病原体入侵机制相关的肠道基因的调节。
