Development of an analytical method for the metaproteomic investigation of bioaerosol from work environments

The metaproteomic analysis of air particulate matter provides valuable information about the properties of bioaerosols in the atmosphere and their influence on climate and public health. In this work, a new method for the extraction and analysis of proteins in airborne particulate matter from quartz microfiber filters was developed. Different protein extraction procedures were tested to select the best extraction protocol based on protein recovery. The optimized method was tested for the extraction of proteins from spores of ubiquitous bacteria species and used for the metaproteomic characterization of filters from three work environments. In particular, ambient aerosol samples were collected in a composting plant, in a wastewater treatment plant and in an agricultural holding. A total of 179, 15, 205 and 444 proteins were identified in the composting plant, the wastewater treatment plant and the agricultural holding, respectively. In agreement with the major categories of primary biological aerosol particles, all identified proteins originated primarily from fungi, bacteria and plants.The paper is the first metaproteomic study applied to bioaerosol samples collected in occupationally relevant environmental sites and, even though not aimed at monitoring the risk exposure of workers, it provides information on the possible exposure in the working environmental sites. This article is protected by copyright. All rights reserved.