title: Diversity, abundance and activity of ammonia-oxidizing microorganisms in fine particulate matter.
abstract: Increasing ammonia emissions could exacerbate air pollution caused by fine particulate matter (PM2.5). Therefore, it is of great importance to investigate ammonia oxidation in PM2.5. This study investigated the diversity, abundance and activity of ammonia oxidizing archaea (AOA), ammonia oxidizing bacteria (AOB) and complete ammonia oxidizers (Comammox) in PM2.5collected in Beijing-Tianjin-Hebei megalopolis, China. Nitrosopumilus subcluster 5.2 was the most dominant AOA. Nitrosospira multiformis and Nitrosomonas aestuarii were the most dominant AOB. Comammox were present in the atmosphere, as revealed by the occurrence of Candidatus Nitrospira inopinata in PM2.5. The average cell numbers of AOA, AOB and Ca. N. inopinata were 2.82 × 104, 4.65 × 103and 1.15 × 103cell m-3air, respectively. The average maximum nitrification rate of PM2.5was 0.14 μg (NH4+-N) [m3air·h]-1. AOA might account for most of the ammonia oxidation, followed by Comammox, while AOB were responsible for a small part of ammonia oxidation. Statistical analyses showed that Nitrososphaera subcluster 4.1 was positively correlated with organic carbon concentration, and Nitrosomonas eutropha showed positive correlation with ammonia concentration. Overall, this study expanded our knowledge concerning AOA, AOB and Comammox in PM2.5and pointed towards an important role of AOA and Comammox in ammonia oxidation in PM2.5.
authors.affiliation: College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China.
authors.forename: Jing-Feng
authors.initials: JF
authors.lastname: Gao
authors.affiliation: College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China.
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Fan
authors.affiliation: College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China.
authors.forename: Kai-Ling
authors.initials: KL
authors.lastname: Pan
authors.affiliation: College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China.
authors.forename: Hong-Yu
authors.initials: HY
authors.lastname: Li
authors.affiliation: College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China.
authors.forename: Li-Xin
authors.initials: LX
authors.lastname: Sun
mesh_terms: D000391:Air Microbiology; D000641:Ammonia / Q000378:metabolism*; D001105:Archaea / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D044822:Biodiversity; D002681:China; D002947:Cities; D002980:Climate; D005798:Genes, Bacterial; D005843:Geography; D007221:Industry; D058465:Nitrification; D010084:Oxidation-Reduction; D010316:Particle Size; D052638:Particulate Matter; D010802:Phylogeny; D021521:Ribotyping; D013383:Suburban Population
chemical_list: D052638:Particulate Matter; D000641:Ammonia