AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Structure and Function of Airborne Bacterial Communities: From Classrooms to Mountaintops
ANN M. WOMACK, James F. Meadow, Dan Jaffe, G.Z. Brown, Brendan J. M. Bohannan, Jessica L. Green, University of Oregon
Abstract Number: 482 Working Group: Bioaerosols: Characterization and Environmental Impact
Abstract Our understanding of bioaerosol-associated microbial communities is expanding as variation in the structure and diversity of airborne communities among environments and over space and time is beginning to be quantified. However, there remain fundamental knowledge gaps in our understanding of the forces that shape this variation and of the ecological function of these communities. Our group uses targeted high-throughout sequencing methods to elucidate the drivers of diversity and structure in bacterial bioaerosol communities in indoor and outdoor environments. In the built environment, we have applied DNA-based molecular methods to study the relative roles of occupancy, ventilation strategy, and outdoor air communities in shaping the diversity and composition of airborne bacterial communities in a high-traffic university building. Ventilation and outdoor air communities had a significant effect on indoor airborne bacterial community composition; changes in outdoor air communities were detected inside following a time lag associated with differing ventilation strategies. However, this study and others using similar methods have a significant drawback in that DNA-based methods census the entire bacterial community, which includes dead and dormant cells. Surveying the total community without partitioning the active members complicates our ability to make inferences about the function of microbial communities particularly in systems where a large proportion of cells are expected to be dead or dormant. In order to distinguish between the dead/dormant and metabolically active portions of the community, we have developed methods to sample and study bioaerosols using RNA-based methods. We have applied these methods at a high-elevation site to characterize the diversity and composition of metabolically active bacterial communities following long distance transport. Partitioning airborne bacterial diversity into the total community versus the active community will allow us to identify important functional groups and will yield important clues about the function bacterial communities in the atmosphere.