AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Protein Biomarkers on Airborne Fungal Spores are Modified by Ozone During Environmentally Relevant Exposures
ODESSA GOMEZ, Anne Perring, Darrel Baumgardner, Mark T. Hernandez, University of Colorado Boulder
Abstract Number: 428 Working Group: Bioaerosols
Abstract Microbiological aerosols (bioaerosol) can contribute to a significant portion of atmospheric and indoor particulate matter, and the extent to which gaseous air pollutants can modify surface characteristics of environmentally relevant bioaerosols remains unclear. This work evaluated the potential for common gaseous air pollutants to modify the surfaces of ubiquitous types of airborne fungal spores using established techniques for characterizing the quantity and activity of sentinel proteins in fungal spore coats, including important allergens.
We obtained independent lines of direct evidence for oxidative protein modifications to the cell walls of microbial bioaerosols (pure cultures of young Aspergillus spp. spores) in controlled chamber studies (24 cubic meters) that were maintained under conditions that mimic summer exposures to ground-level ozone at different relative humidity levels. Results show decreases in both particle fluorescence intensity and enzymatic cell wall activity (normalized to spore counts) after only a few hours of ozone exposure. As judged by a portable wideband integrated bioaerosol sensor (WIBS (IV)), differences in specific fluorescence begin to appear within approximately an hour of ozone exposure. Intrinsic enzyme activity also decreased in response to ozone exposure where beta-N-acetylhexosaminidase (NAHA) was used as a biomarker (Mycometer). The NAHA activity was found to decrease after exposure to an average ozone concentration of 200 ppb for less than 2hours. Surface allergen modification assessed by the multiplex array for indoor allergens (MARIA) will also be presented. Preliminary results outlined in this presentation will contribute to limited existing evidence of the impact of atmospherically relevant oxidation processes on bioaerosols present in the outdoor and indoor environments.