Division of Biotechnology, Jeonbuk National University, Iksan, Republic of Korea; BioTechnology Institute, University of Minnesota, St. Paul, MN, USA; Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN, USA.
Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN, USA.
Sci Total Environ. 2022 Feb 25;809:151127. doi: 10.1016/j.scitotenv.2021.151127. Epub 2021 Oct 22.
Capitella teleta, a marine polychaete that feeds on a refractory diet consisting of sediment, was shown to contain unique gut microbiota comprised of microbial functional groups involved in fermentation. Results of our previous studies showed that C. teleta's core gut microbiota were dominated by propionibacteria, and that these bacteria were more abundant in worms than in sediment and feces. In order to test the hypothesis that the worm nutritionally benefits from its gut microbiota, we identified, and genetically and biochemically characterized Cutibacterium acnes strains (formerly Propionibacterium acnes) that were isolated from the gut of C. teleta. Here we show that 13 worm-isolated Cutibacterium acnes strains primarily belonged to phylotype group IB, likely as a clonal population. We also provide evidence that all tested strains produced propionate and vitamin B, which are essential host-requiring microbial metabolites. The presence of C. acnes in C. teleta was not unique to our worm culture and was also found in those obtained from geographically distant laboratories located in the U.S. and Europe. Moreover, populations of worm gut-associated C. acnes increased following antibiotic treatment. Collectively, results of this study demonstrated that C. acnes is a member of the worm's core functional microbiota and is likely selectively favored by the physiology and chemistry of the host gut environment. To our knowledge, this is the first report of the presence of C. acnes in the C. teleta gut. Our data strongly suggest that C. acnes, a bacterium previously studied as an opportunistic pathogen, can likely act as a symbiont in C. teleta providing the host essential nutrients for survival, growth, and reproduction.
小头虫，一种以沉积物为主要食物的海洋多毛类环节动物，其肠道内含有独特的微生物菌群，这些菌群参与发酵过程。我们之前的研究结果表明，小头虫的核心肠道微生物群主要由丙酸杆菌组成，而且这些细菌在蠕虫体内的丰度高于沉积物和粪便中。为了验证蠕虫从其肠道微生物群中获得营养益处的假设，我们从小头虫的肠道中分离出并鉴定了具有特定功能的痤疮丙酸杆菌（以前称为丙酸杆菌）菌株，并对其进行了遗传和生化特征分析。在这里，我们表明，从蠕虫中分离出的 13 株痤疮丙酸杆菌菌株主要属于 phylotype group IB，可能是一个克隆种群。我们还提供了证据表明，所有测试的菌株都产生了丙酸和维生素 B，这是宿主必需的微生物代谢物。小头虫肠道中痤疮丙酸杆菌的存在不仅在我们的蠕虫培养物中存在，而且还存在于从美国和欧洲地理位置不同的实验室获得的蠕虫中。此外，在抗生素处理后，蠕虫肠道相关的痤疮丙酸杆菌种群增加。总的来说，这项研究的结果表明，痤疮丙酸杆菌是蠕虫核心功能微生物群的成员，并且可能是由宿主肠道环境的生理学和化学特性选择性地有利于其存在。据我们所知，这是首次报道痤疮丙酸杆菌存在于小头虫肠道中。我们的数据强烈表明，痤疮丙酸杆菌以前被研究为机会性病原体，可能在小头虫中充当共生体，为宿主提供生存、生长和繁殖所必需的营养物质。
