Primary biogenic organic aerosols (PBOA) represent a major fraction of coarse organic matter (OM) in air. Despite their implication in many atmospheric processes and human health problems, we surprisingly know little about PBOA characteristics (i.e., composition, dominant sources, and contribution to airborne-particles). In addition, specific primary sugar compounds (SCs) are generally used as markers of PBOA associated with bacteria and fungi but our knowledge of microbial communities associated with atmospheric particulate matter (PM) remains incomplete. This work aimed at providing a comprehensive understanding of the microbial fingerprints associated with SCs in PM₁₀ (particles smaller than 10µm) and their main sources in the surrounding environment (soils and vegetation). An intensive study was conducted on PM₁₀ collected at rural background site located in an agricultural area in France. We combined high-throughput sequencing of bacteria and fungi with detailed physicochemical characterization of PM₁₀, soils and plant samples, and monitored meteorology and agricultural activities throughout the sampling period. Results shows that in summer SCs in PM₁₀ are a major contributor of OM in air, representing 0.8 to 13.5% of OM mass. SCs concentrations are clearly determined by the abundance of only a few specific airborne fungi and bacteria taxa. The temporal fluctuations in the abundance of only 4 predominant fungal genera, namely Cladosporium, Alternaria, Sporobolomyces and Dioszegia reflect the temporal dynamics in SC concentrations. Among bacteria taxa, the abundance of only Massilia, Pseudomonas, Frigoribacterium and Sphingomonas are positively correlated with SC species. These microbial are significantly enhanced in leaf over soil samples. Interestingly, the overall community structure of bacteria and fungi are similar within PM₁₀ and leaf samples and significantly distinct between PM₁₀ and soil samples, indicating that surrounding vegetation are the major source of SC-associated microbial taxa in PM₁₀ on rural area of France.

Sample types: 

Bacterial and fungal community compositions were surveyed using respectively the Bact02 and Fung02 primer pairs. This files contain different type of samples : letter 'A' corresponds to aerosol samples, while 'F' and 'S' correspond respectively to leaf and soil samples.

Database of MOTUs and sequences

The databases contain the number of reads of the different MOTUs in the samples studied, together with information on taxonomic assignment.