Dallas Jason W, Meshaka Walter E, Zeglin Lydia, Warne Robin W
Department of Biological Sciences, Southern Illinois University Carbondale, Carbondale, IL, 62901, USA.
Section of Zoology and Botany, State Museum of Pennsylvania, 300 North Street, Harrisburg, PA, 17120, USA.
Mol Biol Rep. 2021 Sep;48(9):6435-6442. doi: 10.1007/s11033-021-06645-x. Epub 2021 Aug 17.
The gut microbiota is an emerging frontier in wildlife research and its importance to vertebrate health and physiology is becoming ever more apparent. Reptiles, in particular snakes, have not received the same attention given to other vertebrates and the composition of their wild gut microbiome remains understudied. The primary goal of this work was to describe the cloacal microbiota of two Colubrids, the Eastern Gartersnake (Thamnophis sirtalis sirtalis) and the Northern Watersnake (Nerodia sipedon sipedon), and if their cloacal microbiota differed as well as if it did between a wetland and upland population of the former species.
We utilized next-generation sequencing of cloacal swabs-a non-destructive proxy for the gut microbiota. The cloacal microbiome of Eastern Gartersnakes (N = 9) was like those of other snakes being comprised of Proteobacteria, Bacteroidetes, and Firmicutes, while that of Northern Watersnakes (N = 6) was dominated by Tenericutes. Seven microbial operational taxonomic units (OTUs), all members of Proteobacteria, were shared among all individuals and were indicative of a core microbiome in Eastern Gartersnakes, but these OTUs were not particularly relevant to Northern Watersnakes. The latter had greater OTU richness than did Eastern Gartersnakes, and habitat did not have any apparent effect on the microbial community composition in Eastern Gartersnakes.
Our findings suggest host taxonomy to be a determining factor in the cloacal microbiota of snakes and that Tenericutes are associated with aquatic habitats. This is the first report to examine the cloacal microbiome of these species and provides a useful foundation for future work to build upon.
肠道微生物群是野生动物研究中一个新兴的前沿领域，其对脊椎动物健康和生理的重要性日益明显。爬行动物，尤其是蛇类，尚未得到与其他脊椎动物相同的关注，其野生肠道微生物群的组成仍未得到充分研究。这项工作的主要目标是描述两种游蛇科蛇类——东部束带蛇（Thamnophis sirtalis sirtalis）和北水蛇（Nerodia sipedon sipedon）的泄殖腔微生物群，以及它们的泄殖腔微生物群是否存在差异，以及前一种蛇的湿地和高地种群之间的泄殖腔微生物群是否存在差异。
我们利用泄殖腔拭子的下一代测序技术——一种用于肠道微生物群的非侵入性替代方法。东部束带蛇（N = 9）的泄殖腔微生物群与其他蛇类相似，由变形菌门、拟杆菌门和厚壁菌门组成，而北水蛇（N = 6）的泄殖腔微生物群则以柔膜菌门为主。七个微生物操作分类单元（OTU），均为变形菌门成员，在所有个体中都有共享，表明是东部束带蛇的核心微生物群，但这些OTU与北水蛇没有特别的相关性。北水蛇的OTU丰富度高于东部束带蛇，栖息地对东部束带蛇的微生物群落组成没有明显影响。
我们的研究结果表明宿主分类是蛇类泄殖腔微生物群的一个决定性因素，并且柔膜菌门与水生栖息地有关。这是第一份研究这些物种泄殖腔微生物群的报告，为未来的研究工作提供了有用的基础。
