Department of Biochemistry, Microbiology, and Immunology, Wayne State University, Detroit, Michigan, USA.
Infect Immun. 2021 Aug 16;89(9):e0015121. doi: 10.1128/IAI.00151-21.
Zebrafish (Danio rerio) are an attractive model organism for a variety of scientific studies, including host-microbe interactions. The organism is particularly useful for the study of aquatic microbes that can colonize vertebrate hosts, including Vibrio cholerae, an intestinal pathogen. V. cholerae must colonize the intestine of an exposed host for pathogenicity to occur. While numerous studies have explored various aspects of the pathogenic effects of V. cholerae on zebrafish and other model organisms, few, if any, have examined how a V. cholerae infection alters the resident intestinal microbiome and the role of the type six secretion system (T6SS) in that process. In this study, 16S rRNA gene sequencing was utilized to investigate how strains of V. cholerae both with and without the T6SS alter the aforementioned microbial profiles following an infection. V. cholerae infection induced significant changes in the zebrafish intestinal microbiome, and while not necessary for colonization, the T6SS was important for inducing mucin secretion, a marker for diarrhea. Additional salient differences to the microbiome were observed based on the presence or absence of the T6SS in the V. cholerae utilized for challenging the zebrafish hosts. We conclude that V. cholerae significantly modulates the zebrafish intestinal microbiome to enable colonization and that the T6SS is important for pathogenesis induced by the examined V. cholerae strains. Furthermore, the presence or absence of T6SS differentially and significantly affected the composition and structure of the intestinal microbiome, with an increased abundance of other bacteria observed in the absence of V. cholerae T6SS.
斑马鱼（Danio rerio）是一种用于各种科学研究的有吸引力的模式生物，包括宿主-微生物相互作用。该生物特别适用于研究可以定植脊椎动物宿主的水生微生物，包括霍乱弧菌，一种肠道病原体。霍乱弧菌必须定植暴露宿主的肠道才能发生致病性。虽然许多研究已经探索了霍乱弧菌对斑马鱼和其他模式生物的致病作用的各个方面，但很少（如果有的话）研究了霍乱弧菌感染如何改变常驻肠道微生物组以及该过程中 VI 型分泌系统（T6SS）的作用。在这项研究中，使用 16S rRNA 基因测序来研究具有和不具有 T6SS 的霍乱弧菌菌株在感染后如何改变上述微生物谱。霍乱弧菌感染诱导斑马鱼肠道微生物组发生显著变化，尽管 T6SS 不是定植所必需的，但它对于诱导粘蛋白分泌很重要，粘蛋白分泌是腹泻的标志物。根据用于挑战斑马鱼宿主的霍乱弧菌是否存在 T6SS，观察到了对微生物组的其他明显差异。我们得出结论，霍乱弧菌显著调节斑马鱼肠道微生物组以实现定植，并且 T6SS 对于所检查的霍乱弧菌菌株引起的发病机制很重要。此外，T6SS 的存在与否对肠道微生物组的组成和结构产生了不同且显著的影响，在缺乏霍乱弧菌 T6SS 的情况下，观察到其他细菌的丰度增加。
