RUI: Microbial Processes Facilitating Xylophagy in a Loricariid

这个项目的重点是一种迷人的鱼类——盔甲鲶鱼，来自Panaque属，其中包括能够通过吃木头来生存和获取能量的成员。食木或食木是一种罕见的饮食策略，通常涉及复杂的肠道微生物群落。该项目的一个主要目标是确定食木Panaque nigrolineatus胃肠道（GI）中存在的微生物群落，并研究用于纤维素分解和固氮的机制，使这种食木生活方式成为可能。将进行一项长期的饲料试验，比较饲喂草本饲料的鱼和饲喂纯木材饲料的鱼的微生物群落。DNA测序和其他分子方法将允许描述不同饮食制度下鱼类的微生物群落，此外，比较鱼类胃肠道不同区域的微生物群落，精确定位涉及纤维素分解的关键区域。固氮作用也将通过分离参与这一重要全球过程的基因和培养与Panaque胃肠道相关的固氮微生物来研究。该项目的更广泛的科学意义包括增强我们对纤维素分解和固氮基因多样性的认识，以及在木食鱼类中微生物群落的重要性。纤维素是生物圈中含量最丰富的碳聚合物，但其降解途径尚不明确。由于纤维素是全球碳循环中的重要化合物，也是生物质燃料发电的潜在来源，因此更好地了解其在环境中的降解至关重要。此外，新途径的发现可能对生物燃料生产和全球碳氮循环具有重要意义。本研究项目对教育的影响包括对研究生和本科生的培养。计划与巴尔的摩市一所小学开展外展活动，为3-8年级的孩子提供实践机会，目标是促进这些孩子将科学作为职业选择。

This project focuses on a fascinating group of fish - armored catfish, from the genus Panaque, which include members that are capable of surviving and obtaining energy by eating wood. Wood eating, or xylophagy, is a rare dietary strategy and often involves a complex intestinal tract microbial community. A major goal of this project is to identify the microbial communities present in the gastrointestinal (GI) tract of the wood eating Panaque nigrolineatus and examine the mechanisms used for cellulose decomposition and nitrogen fixation that enable this xylophagous lifestyle. A long-term dietary experiment will be performed to compare the microbial communities in fish fed an herbaceous diet to those fed a wood-only diet. DNA sequencing and other molecular methods will allow the description of microbial communities in fish subjected to different dietary regimes and furthermore, compare microbial communities in different regions of the fish GI tract, pinpointing key areas involved in cellulose breakdown. Nitrogen fixation will also be examined by isolating genes involved in this vital global process, and by culturing nitrogen fixing microorganisms associated with the Panaque GI tract. Broader scientific implications of this project include enhancing our knowledge of cellulolytic and nitrogen fixation gene diversity and the importance of the microbial community within xylophagous fish. Cellulose is the most abundant carbon polymer in the biosphere, yet, few degradation pathways have been characterized. As cellulose is an important compound in the global carbon cycle and a potential source for biomass fuel generation, gaining a better better understanding of its degradation in the environment is critical. Furthermore, discovery of novel pathways may have critical implications for biofuel production and the global carbon and nitrogen cycles. Educational impacts include the training of graduate and undergraduate students during this research project. An outreach activity with a Baltimore City elementary school is planned, enabling a hands-on opportunity for children in grades 3-8 with the goal of promoting science as a career choice for these children.