Urban Aerosols Harbor Diverse and Dynamic Bacterial Populations

Ecology Department, Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 02/2007; 104(1):299-304. DOI: 10.1073/pnas.0608255104
Source: PubMed


Considering the importance of its potential implications for human health, agricultural productivity, and ecosystem stability, surprisingly little is known regarding the composition or dynamics of the atmosphere's microbial inhabitants. Using a custom high-density DNA microarray, we detected and monitored bacterial populations in two U.S. cities over 17 weeks. These urban aerosols contained at least 1,800 diverse bacterial types, a richness approaching that of some soil bacterial communities. We also reveal the consistent presence of bacterial families with pathogenic members including environmental relatives of select agents of bioterrorism significance. Finally, using multivariate regression techniques, we demonstrate that temporal and meteorological influences can be stronger factors than location in shaping the biological composition of the air we breathe.

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    • "In addition, airborne microorganisms on North American mountains (2700 m above sea level) were found to change in response to Asian dust events that included highly diverse bacterial species (Smith et al., 2013). Pyrosequencing technology that can analyze large numbers of nucleotide sequences has been applied for estimating the variations in the composition of bacterial communities on mountains (Bowers et al., 2012) and in rural and urban areas (Brodie et al., 2007) at the family level. However, there are a few of researches investigating the bacterial communities at high altitudes above ground level using pyrosequencing analysis (Bowers et al., 2009; DeLeon-Rodriguez et al., 2013), and the vertical distribution of airborne bacteria between the ground and high altitudes is unclear. "

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