Project name: Airborne bacteria in Milan

Description: Bacteria represent a relevant fraction of atmospheric suspended particles. It is known that airborne bacteria can significantly affect human health and ecosystems. However, the abundance and diversity of airborne microorganisms and the factors influencing their diversity remain poorly investigated. In the present work we used quantitative polymerase chain reaction (PCR) and Illumina technology to provide a thorough description of airborne microbial communities of the Milan urban area (Northern Italy). We collected 40 air samples, ten per season. Total bacterial abundance was about 104 ribosomal operons m-3 of sampled air. Communities were dominated by Actinobacteridae, Clostridiales, Sphingobacteriales and a few proteobacterial orders (Burkholderiales, Rhizobiales, Sphingomonadales, Pseudomonadales). A significant abundance of Chloroplasts was detected, especially in warmer seasons, due to the presence of plant debris and pollens in the particulate matter. A seasonal variability in the composition of microbial communities was found, mainly due to a higher abundance of Actinobacteridae and lower abundance of Chloroplasts in samples collected on cold days. At the same time, intra-season variation in community composition was comparable to inter-season variation. Soil and plants were the sources which most affected airborne bacterial communities. This study demonstrated the potential of the Illumina technology and quantitative real-time PCR to investigate the microbiological component of the atmosphere, an environment largely neglected by previous studies.

Data type: Other

Sample scope: Monoisolate

Release date: 2012-10-15