ACP: Exometabolomic exploration of culturable airborne microorganisms from an urban atmosphere

Professor Pingqing Fu’s team from the School of Earth System Science used ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to investigate the molecular composition of exometabolites from typical bacteria and fungi isolated from the urban atmosphere. The study revealed key metabolic processes in these microorganisms, providing strong evidence for understanding the complex relationships between atmospheric microorganisms and the environment.

The interactions of metabolically active atmospheric microorganisms with cloud organic matter can influence the atmospheric carbon cycle. Upon deposition, atmospheric microorganisms can alter microbial communities in surface Earth systems. Atmospheric microorganisms play a key role in the global biogeochemical cycle, and their diversity, abundance, and metabolic abilities have a profound impact on atmospheric chemistry, ecosystems, and even human health. However, the metabolic activities and their potential environmental effects of atmospheric microorganisms remain less understood.

The study of Professor Pingqing Fu’s team revealed significant chemical characteristics in the exometabolites produced by bacteria and fungi: they exhibited lower H/C and higher O/C ratios, primarily consisting of aliphatic/peptide-like and carboxyl-rich alicyclic molecule (CRAM)-like compounds. This finding suggests that high-oxygen organic molecules produced by atmospheric microorganisms could enhance the oxidation of organic matter in clouds and aerosols, thereby influencing the organic carbon budget in atmospheric systems. Bacterial strains produced more abundant CHONS compounds (25.2%), while fungal exometabolites were rich in CHO compounds (31.7%). The high molecular diversity of these metabolites reflects the unique metabolic pathways and ecological niche differentiation of different microorganisms. This study not only systematically revealed the exometabolomic features of culturable microorganisms in urban atmospheres but also provided valuable data and theoretical support for understanding the complex roles of atmospheric microorganisms in atmospheric chemistry and biogeochemical cycles.

This study, titled Exometabolomic exploration of culturable airborne microorganisms from an urban atmosphere, was published in the Atmospheric Chemistry and Physics, a journal of the European Geosciences Union (EGU). Rui Jin, a PhD student from the School of Earth System Science, Tianjin University, is the first author, with Professor Pingqing Fu and Associate Professor Wei Hu as co-corresponding authors. This study was supported by the National Natural Science Foundation of China (grant nos. 42221001, 42130513, and 42394151).

By School of Earth System Science

Editor: Sun Xiaofang