Structural Variation in the Bacterial Community Associated with Airborne Particulate Matter in Beijing, China, during Hazy and Nonhazy Days

ABSTRACT The structural variation of the bacterial community associated with particulate matter (PM) was assessed in an urban area of Beijing during hazy and nonhazy days. Sampling for different PM fractions (PM 2.5 [ 10 [ R = 0.157, P 2 concentration, relative humidity, PM 10 concentration, and CO concentration were significant factors that associated with airborne bacterial community composition. Only six genera increased across PM 10 samples (Dokdonella, Caenimonas, Geminicoccus, and Sphingopyxis) and PM 2.5 samples (Cellulomonas and Rhizobacter), while a large number of taxa significantly increased in total suspended particulate samples, such as Paracoccus, Kocuria, and Sphingomonas. Network analysis indicated that Paracoccus, Rubellimicrobium, Kocuria, and Arthrobacter were the key genera in the airborne PM samples. Overall, the findings presented here suggest that diverse airborne bacterial communities are associated with PM and provide further understanding of bacterial community structure in the atmosphere during hazy and nonhazy days. IMPORTANCE The results presented here represent an analysis of the airborne bacterial community associated with particulate matter (PM) and advance our understanding of the structural variation of these communities. We observed a shift in bacterial community composition with PM fractions but no significant difference with haze levels. This may be because the bacterial differences are obscured by high bacterial diversity in the atmosphere. However, we also observed that a few genera (such as Methylobacillus, Tumebacillus, and Desulfurispora) increased significantly on heavy-haze days. In addition, Paracoccus, Rubellimicrobium, Kocuria, and Arthrobacter were the key genera in the airborne PM samples. Accurate and real-time techniques, such as metagenomics and metatranscriptomics, should be developed for a future survey of the relationship of airborne bacteria and haze.