111 / 2025-03-31 23:11:49

Raman in situ quantitative analysis of biologically mediated elemental cycling processes in the deep sea

Raman spectroscopy,in situ detection,Cold seep,biologically mediated cycling

Theme 1: Novel Tools and Techniques in Geobiology > Session 1c: Unraveling Life-Earth Interactions across Extreme Environments and Beyond from Innovative Approaches in Geobiology

Deep-sea microbial-mediated carbon and sulfur cycling represents a critical frontier in marine science, serving as both a cornerstone for stabilizing extreme ecosystems and a pivotal regulator of global climate dynamics. Environmental factors profoundly affect these microbial-mediated elemental cycling processes. However, traditional sampling and analysis techniques are limited by uneven sampling, contamination and sample damage, which make it difficult to obtain in situ data over long time series, thus hindering in-depth research. Raman spectroscopy, with its advantages of in situ and nondestructive detection, provides new ideas for the study of deep-sea microbial-mediated elemental cycling. In view of this, we targeted cold spring microorganisms and utilized confocal microscopic Raman for dynamic monitoring, realizing online quantitative tracking of microbial metabolic processes. Through three-dimensional Raman imaging, the dynamic mechanism of sulfur production by deep-sea microorganisms was deeply analyzed, and its generation and transformation processes were quantitatively revealed. On the subcellular scale, an innovative method for visualization and semi-quantitative analysis of various metabolites was established, and the intracellular transformation of methane mediated by endosymbiotic bacteria was successfully analyzed. Meanwhile, based on the Raman imaging results of endosymbiotic bacteria in tissues and the quantitative analysis of protein spatial structure, the conservation method of methane oxidizing bacteria in biological tissues was optimized. In addition, we constructed a quantitative Raman analysis method for the long-term plastic degradation process by marine microorganisms, which provided methodological support for exploring the impact of novel pollutants on the carbon cycle. These studies not only validate the potential of Raman technology in the study of microbial-mediated elemental cycling in the deep sea, but also provide innovative ideas for in situ monitoring and mechanism elucidation of biogeochemical processes in extreme environments.