Vaughn Stephanie N, Atkinson Carla L, Johnson Paul D, Jackson Colin R
Department of Biology, University of Mississippi, University, MS 38677, USA.
Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487, USA.
Microorganisms. 2023 Oct 4;11(10):2489. doi: 10.3390/microorganisms11102489.
Freshwater mussels are important indicators of the overall health of their environment but have suffered declines that have been attributed to factors such as habitat degradation, a loss of fish hosts, climate change, and excessive nutrient inputs. The loss of mussel biodiversity can negatively impact freshwater ecosystems such that understanding the mussel's gut microbiome has been identified as a priority topic for developing conservation strategies. In this study, we determine whether ethanol-stored specimens of freshwater mussels can yield representative information about their gut microbiomes such that changes in the microbiome through time could potentially be determined from museum mussel collections. A short-term preservation experiment using the invasive clam was used to validate the use of ethanol as a method for storing the bivalve microbiome, and the gut microbiomes of nine native mussel species that had been preserved in ethanol for between 2 and 9 years were assessed. We show that ethanol preservation is a valid storage method for bivalve specimens in terms of maintaining an effective sequencing depth and the richness of their gut bacterial assemblages and provide further insight into the gut microbiomes of the invasive clam and nine species of native mussels. From this, we identify a "core" genus of bacteria () that is potentially common to all freshwater bivalve species studied. These findings support the potential use of ethanol-preserved museum specimens to examine patterns in the gut microbiomes of freshwater mussels over long periods.
淡水贻贝是其所处环境整体健康状况的重要指标，但数量却有所下降，这归因于栖息地退化、鱼类宿主减少、气候变化和营养物质输入过多等因素。贻贝生物多样性的丧失会对淡水生态系统产生负面影响，因此了解贻贝的肠道微生物群已被确定为制定保护策略的优先课题。在本研究中，我们确定乙醇保存的淡水贻贝标本是否能产生有关其肠道微生物群的代表性信息，以便有可能从博物馆的贻贝标本中确定微生物群随时间的变化。使用入侵蛤进行的短期保存实验用于验证乙醇作为保存双壳贝类微生物群方法的有效性，并评估了9种在乙醇中保存2至9年的本地贻贝物种的肠道微生物群。我们表明，就维持有效的测序深度及其肠道细菌群落的丰富度而言，乙醇保存是双壳贝类标本的一种有效保存方法，并进一步深入了解了入侵蛤和9种本地贻贝的肠道微生物群。据此，我们确定了一种细菌的“核心”属（），它可能在所研究的所有淡水双壳贝类物种中都很常见。这些发现支持了利用乙醇保存的博物馆标本长期研究淡水贻贝肠道微生物群模式的可能性。
