Unzueta-Martínez Andrea, Girguis Peter R
Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA.
Appl Environ Microbiol. 2025 Jan 31;91(1):e0109424. doi: 10.1128/aem.01094-24. Epub 2024 Dec 12.
Creating and maintaining an appropriate chemical environment is essential for biomineralization, the process by which organisms precipitate minerals to form their shells or skeletons, yet the mechanisms involved in maintaining calcifying fluid chemistry are not fully defined. In particular, the role of microorganisms in facilitating or hindering animal biomineralization is poorly understood. Here, we investigated the taxonomic diversity and functional potential of microbial communities inhabiting oyster calcifying fluid. We used shotgun metagenomics to survey calcifying fluid microbial communities from three different oyster harvesting sites. There was a striking consistency in taxonomic composition across the three collection sites. We also observed archaea and viruses that had not been previously identified in oyster calcifying fluid. Furthermore, we identified microbial energy-conserving metabolisms that could influence the host's calcification, including genes involved in sulfate reduction and denitrification that are thought to play pivotal roles in inorganic carbon chemistry and calcification in microbial biofilms. These findings provide new insights into the taxonomy and functional capacity of oyster calcifying fluid microbiomes, highlighting their potential contributions to shell biomineralization, and contribute to a deeper understanding of the interplay between microbial ecology and biogeochemistry that could potentially bolster oyster calcification.
Previous research has underscored the influence of microbial metabolisms in carbonate deposition throughout the geological record. Despite the ecological importance of microbes to animals and inorganic carbon transformations, there have been limited studies characterizing the potential role of microbiomes in calcification by animals such as bivalves. Here, we use metagenomics to investigate the taxonomic diversity and functional potential of microbial communities in calcifying fluids from oysters collected at three different locations. We show a diverse microbial community that includes bacteria, archaea, and viruses, and we discuss their functional potential to influence calcifying fluid chemistry via reactions like sulfate reduction and denitrification. We also report the presence of carbonic anhydrase and urease, both of which are critical in microbial biofilm calcification. Our findings have broader implications in understanding what regulates calcifying fluid chemistry and consequentially the resilience of calcifying organisms to 21st century acidifying oceans.
创造并维持适宜的化学环境对于生物矿化至关重要，生物矿化是生物体沉淀矿物质以形成其外壳或骨骼的过程，然而维持钙化液化学性质所涉及的机制尚未完全明确。特别是，微生物在促进或阻碍动物生物矿化方面的作用了解甚少。在此，我们研究了栖息于牡蛎钙化液中的微生物群落的分类多样性和功能潜力。我们使用鸟枪法宏基因组学来调查来自三个不同牡蛎捕捞地点的钙化液微生物群落。三个采集地点的分类组成具有显著的一致性。我们还观察到了先前未在牡蛎钙化液中鉴定出的古菌和病毒。此外，我们鉴定出了可能影响宿主钙化的微生物能量守恒代谢，包括参与硫酸盐还原和反硝化作用的基因，这些基因被认为在微生物生物膜的无机碳化学和钙化过程中起关键作用。这些发现为牡蛎钙化液微生物群落的分类和功能能力提供了新的见解，突出了它们对贝壳生物矿化的潜在贡献，并有助于更深入地理解微生物生态学与生物地球化学之间的相互作用，这可能会增强牡蛎的钙化作用。
先前的研究强调了微生物代谢在整个地质记录中碳酸盐沉积中的影响。尽管微生物对动物和无机碳转化具有生态重要性，但关于微生物群落对双壳类等动物钙化潜在作用的研究有限。在此，我们使用宏基因组学来研究从三个不同地点采集的牡蛎钙化液中微生物群落的分类多样性和功能潜力。我们展示了一个多样的微生物群落，包括细菌、古菌和病毒，并讨论了它们通过硫酸盐还原和反硝化等反应影响钙化液化学性质的功能潜力。我们还报告了碳酸酐酶和脲酶的存在，这两者在微生物生物膜钙化中都至关重要。我们的发现对于理解是什么调节钙化液化学性质以及钙化生物对21世纪海洋酸化的恢复力具有更广泛的意义。
