AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Chemical Modification of Ragweed Pollen Allergens via Ambient Air
RACHEL L. DAVEY, Courtney Seffense, Erick Mattson, J. Alex Huffman, University of Denver
Abstract Number: 896 Working Group: Bioaerosols
Abstract Reactive nitrogen and oxygen species can interact with proteins and cause post-translational modifications (PTMs). Common PTMs seen include oxidation, hydroxylation, and nitration. Nitrotyrosine (n-Tyr) formed in the body via PTM, for example, is used as a biomarker for inflammation and oxidative stress. Previous work has shown that with even relatively low concentrations of urban pollutant gases NO2 and O3, proteins on the surfaces of pollen particles can be nitrated. Related work has shown for an allergenic birch pollen protein (Bet v 1) that nitration promotes an increased allergenic response, but little is known about other atmospherically relevant pollen proteins. Ragweed pollen (Ambrosia artemisiifolia) exists in high concentrations across the US and Europe and represents a significant allergen for a considerable fraction of the population. Here we separately exposed samples of two proteins to ambient air during periods of high NO2 and O3 to test for nitration. We used bovine serum albumin (BSA) as an inexpensive protein model as well as Amb a 1, the major allergen in ragweed pollen. The extent of nitration was tested using absorption spectroscopy and two immunoassays. Nitration products were detected on both proteins, suggesting the possibility for the hypothesized reactions to be relevant to urban atmospheres. Preliminary results of the pilot study will be presented.