The biogeochemistry of dissolved amino acids in the aquatic ecosystems

Marine environments host diverse organisms, each playing a crucial role in various ecological processes. Dissolved free amino acids (DFAAs) represent a key constitutes of dissolved organic matter (DOM) in marine environments. They function as readily available substrates for microorganisms, supporting primary production and facilitating trophic interactions by supplying essential nitrogen and carbon sources. Their rapid turnover links DOM processing with nutrient dynamics and global biogeochemical cycles. This review synthesizes current insights into the sources, distribution, dynamics and ecological roles of DFAAs, emphasizing their significance as crucial components in biochemical pathways in the marine environment, including their significance in biogeochemical cycles, nutrient availability, and responses to environmental changes. We also discuss analytical advances that enable detection of DFAAs at low concentrations in complex seawater matrices. Finally, we highlight how DFAA concentrations can serve as sensitive indicators of environmental shifts, underscoring their importance for monitoring ecosystem health and informing marine conservation strategies. By investigating DFAA dynamics, researchers can gain insights into the intricate processes that govern marine ecosystems and contribute to the conservation and sustainable management of our oceans. Overall, this review paper aims to provide a comprehensive overview of current knowledge on DFAAs in the marine environment.