Assessment Of Microbial Communities In Atmospheric Particulate Matter Of Major Cities In Northern Xinjiang

Recently, particulate matter carried with microorganisms has been reported to be responsible for human allergy and respiratory disease, but research on the microbial content of the atmosphere has been less considered. The unique geographical environment and adverse weather conditions of Xinjiang, cause more serious particulate matter pollution, but research on the microbial content of the atmosphere has not been commenced.In this study, selected major citied of northern Xinjiang（Urumqi and Shihezi） for the TSP, PM₁₀, PM_2.5 and PM₁ sample collection, 16 S and 18 S rRNA gene sequencing were conducted to investigate the microbial composition of Urumqi and Shihezi’s particulate matter. Results showed that bacteria shannon index sequence is: summer > spring > winter > autumn, shannon index of fungi for spring > winter > autumn > summer. Particles microbial diversity is stronger in the spring and summer, the weaker in autumn and winter. At the same site, PM₁₀’s shannon index were greater than in the TSP. In winter, shannon index size order for PM_2.5 > PM₁₀ > TSP, the smaller the particle size, the stronger the bacterial population diversity. Fungal shannon index size order for PM₁₀ > TSP > PM_2.5. This could be due to bacteria smaller particle size, it is easy to be adsorpted in the smaller aerodynamic diameter particles, but the fungi particle size is bigger, and it is easy to form spores, so fungal diversity is strong in PM₁₀.At phylum level, the bacterial community is mainly composed of Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes and Cyanobacteria, Proteobacteria accounted for the most proportion, especially in winter. Ascomycota, Basidiomycota and Zygomycota constitute the main part of the fungal microbial community at the phylum level. At genus level, plant-associated are abundent in summer, such as Streptophyta. Acinetobacter and Pseudomonas are abundent in winter.At same sampling site, bacterial and fungal community structure are similar between different particle size at the phylum, order and genus level, but different relative abundence. In different cities, bacterial community structure are different, fungi are similar, but the dominant fungi have different relative abundance. In the same city, the same diameter particles’ microbial community structure are similar in same season.The sequences of several pathogenic bacteria and opportunistic pathogens were also detected, such as Acinetobacter, Delftia, Serratia, Chryseobacterium, which may impact on immunocompromised populations（elderly, children and postoperative convalescence patients）, and some fungal genera may cause several plant diseases. Results of this study are respected to provide a reference for human life.