Abstract

ABSTRACTBacteria are ubiquitous and abundant in the atmosphere and some of them are potential pathogens known to cause diseases or allergies in humans. However, the quantities and compositions of total airborne bacterial community and their relationships with environmental factors remain poorly investigated. Here, a case study of the total airborne bacteria of PM2.5 collected at six cities in Beijing-Tianjin-Hebei (BTH) megalopolis, China were profiled using quantitative polymerase chain reaction (qPCR) and Illumina MiSeq (PE300) sequencing. qPCR results showed the high abundance of total airborne bacteria of PM2.5 in BTH, ranging from 4.82 × 104 ± 1.58 × 103 to 2.64 × 105 ± 9.63 × 104 cell m–3 air, and averaged 1.19 × 105 cell m–3 air. The six PM2.5 samples were classified into three groups. Proteobacteria, Cyanobacteria, Actinobacteria and Firmicutes were the four dominant phyla of PM2.5. 18 common potential pathogens with extremely low percentage (3.61%) were observed, which were dominated by Enterococcus faecium and Escherichia coli. Plants and soil are probably the main sources of bacteria in PM2.5, as suggested by the high percentages of Chloroplast, plant-associated bacteria (e.g., Rhizobiales and Sphingomonadales) and soil-inhabiting bacteria (e.g., Burkholderiales and Pseudomonadales). Variation partitioning analysis (VPA) indicated that the atmospheric pollutants explained the most of the variation (31.90%) in community structure of PM2.5, followed by meteorological conditions (15.73%) and the chemical compositions of PM2.5 (11.32%). The case study furthers our understanding of the diversity and composition of airborne bacterial communities of PM2.5 in BTH, and also identified the main factors shaping the bacterial communities.

Highlights

  • Atmospheric fine particulate matter, PM2.5, has been considered as the major air pollutant in urban cities (Cao et al, 2014), especially in Beijing-Tianjin-Hebei (BTH) megalopolis, one of the rapidly developing regions of China

  • A case study of the total airborne bacteria of PM2.5 collected at six cities in Beijing-Tianjin-Hebei (BTH) megalopolis, China were profiled using quantitative polymerase chain reaction and Illumina MiSeq (PE300) sequencing. qPCR results showed the high abundance of total airborne bacteria of PM2.5 in BTH, ranging from 4.82 × 104 ± 1.58 × 103 to 2.64 × 105 ± 9.63 × cell m–3 air, and averaged 1.19 × cell m–3 air

  • The concentrations of PM2.5 ranged from 35.42 μg m–3 (BDH) to 194.44 μg m–3 (TS), which were higher in TS, BD and TJ than LF, BJ and BDH (Fig. 1(a))

Read more

Summary

INTRODUCTION

Atmospheric fine particulate matter, PM2.5, has been considered as the major air pollutant in urban cities (Cao et al, 2014), especially in Beijing-Tianjin-Hebei (BTH) megalopolis, one of the rapidly developing regions of China. It has been suggested that the relative abundances of several respiratory microbial allergens and pathogens increased with the increasing concentrations of particulate matter in urban area (Cao et al, 2014). It is important and necessary to investigate the diversity and composition of total airborne bacteria and the potential pathogens of PM2.5 in urban areas. Aerosol and Air Quality Research, 17: 788–798, 2017 independent methods, especially the high-throughput sequencing technology has been widely applied to investigate the diversity of total airborne bacterial communities, including cultivatable microorganisms, viable but noncultivatable microorganisms and dead microorganisms. The Illumina Genome Analyser IIx sequencing (2 × 150 bp) has been applied to investigate the bacterial populations of total suspended particulate matter (TSP) collected in an urban area of Milan (Italy) (Bertolini et al, 2013). The relationship between total airborne bacterial communities and the environmental factors was further discussed based on the Spearman′s rank correlation coefficients (SRCC), Principal Components Analysis (PCA), Redundancy Analysis (RDA) and Variation Partitioning Analysis (VPA)

METHODS
RESULTS AND DISCUSSION
CONCLUSIONS

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.