title: Elevated nitrate enriches microbial functional genes for potential bioremediation of complexly contaminated sediments.
abstract: Nitrate is an important nutrient and electron acceptor for microorganisms, having a key role in nitrogen (N) cycling and electron transfer in anoxic sediments. High-nitrate inputs into sediments could have a significant effect on N cycling and its associated microbial processes. However, few studies have been focused on the effect of nitrate addition on the functional diversity, composition, structure and dynamics of sediment microbial communities in contaminated aquatic ecosystems with persistent organic pollutants (POPs). Here we analyzed sediment microbial communities from a field-scale in situ bioremediation site, a creek in Pearl River Delta containing a variety of contaminants including polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs), before and after nitrate injection using a comprehensive functional gene array (GeoChip 4.0). Our results showed that the sediment microbial community functional composition and structure were markedly altered, and that functional genes involved in N-, carbon (C)-, sulfur (S)-and phosphorus (P)- cycling processes were highly enriched after nitrate injection, especially those microorganisms with diverse metabolic capabilities, leading to potential in situ bioremediation of the contaminated sediment, such as PBDE and PAH reduction/degradation. This study provides new insights into our understanding of sediment microbial community responses to nitrate addition, suggesting that indigenous microorganisms could be successfully stimulated for in situ bioremediation of POPs in contaminated sediments with nitrate addition.
authors.affiliation: 1] Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, China [2] State Key Laboratory of Applied Microbiology Southern China, Guangzhou, China.
authors.forename: Meiying
authors.initials: M
authors.lastname: Xu
authors.affiliation: 1] Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, China [2] College of Environmental Sciences and Engineering, Guilin University of Technology, Guilin, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, China.
authors.forename: Chunyu
authors.initials: C
authors.lastname: Xia
authors.affiliation: 1] Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, China [2] State Key Laboratory of Applied Microbiology Southern China, Guangzhou, China.
authors.forename: Yuming
authors.initials: Y
authors.lastname: Zhong
authors.affiliation: 1] Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, China [2] State Key Laboratory of Applied Microbiology Southern China, Guangzhou, China.
authors.forename: Guoping
authors.initials: G
authors.lastname: Sun
authors.affiliation: 1] Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, China [2] State Key Laboratory of Applied Microbiology Southern China, Guangzhou, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Guo
authors.affiliation: Department of Botany and Microbiology, Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA.
authors.forename: Tong
authors.initials: T
authors.lastname: Yuan
authors.affiliation: Department of Botany and Microbiology, Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA.
authors.forename: Jizhong
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Botany and Microbiology, Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA.
authors.forename: Zhili
authors.initials: Z
authors.lastname: He
mesh_terms: D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism; D017753:Ecosystem; D064351:Genes, Microbial; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology*; D009566:Nitrates / Q000032:analysis / Q000378:metabolism*; D010758:Phosphorus / Q000378:metabolism; D013455:Sulfur / Q000378:metabolism; D014873:Water Pollutants / Q000378:metabolism*
chemical_list: D009566:Nitrates; D014873:Water Pollutants; D010758:Phosphorus; D013455:Sulfur; D002244:Carbon