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Ammonia oxidizing bacteria

Chao Wei, Wenjie He, Li Wei, Jun Ma, Chunying Li
The biodegradation-electron transfer with sulfur metabolism integrated (BESI(®)) process was used for the treatment of real flue gas desulfurization wastewater. The BESI(®) process consists of an anaerobic activated sludge reactor, an anoxic activated sludge reactor, and an aerobic bio-film reactor. The performance of the integrated process was evaluated by the removal efficiencies of organics and nitrogen pollutants. The sulfate in the wastewater was used as an abundant sulfur source to drive the integrated process...
July 22, 2017: Bioprocess and Biosystems Engineering
Alma E Parada, Jed A Fuhrman
Marine archaea are critical contributors to global carbon and nitrogen redox cycles, but their temporal variability and microbial associations across the water column are poorly known. We evaluated seasonal variability of free living (0.2-1 μm size fraction) Thaumarchaea Marine Group I (MGI) and Euryarchaea Marine Group II (MGII) communities and their associations with the microbial community from surface to seafloor (890 m) over 5 years by 16S rRNA V4-V5 gene sequencing. MGI and MGII communities demonstrated distinct compositions at different depths, and seasonality at all depths...
July 21, 2017: ISME Journal
Ellen M Black, Michael S Chimenti, Craig L Just
Targeted qPCR and non-targeted amplicon sequencing of 16S rRNA genes within sediment layers identified the anaerobic ammonium oxidation (anammox) niche and characterized microbial community changes attributable to freshwater mussels. Anammox bacteria were normally distributed (Shapiro-Wilk normality test, W-statistic =0.954, p = 0.773) between 1 and 15 cm depth and were increased by a factor of 2.2 (p < 0.001) at 3 cm below the water-sediment interface when mussels were present. Amplicon sequencing of sediment at depths relevant to mussel burrowing (3 and 5 cm) showed that mussel presence reduced observed species richness (p = 0...
2017: PeerJ
Jonathan D Caranto, Kyle M Lancaster
Ammonia (NH3)-oxidizing bacteria (AOB) emit substantial amounts of nitric oxide (NO) and nitrous oxide (N2O), both of which contribute to the harmful environmental side effects of large-scale agriculture. The currently accepted model for AOB metabolism involves NH3 oxidation to nitrite (NO2(-)) via a single obligate intermediate, hydroxylamine (NH2OH). Within this model, the multiheme enzyme hydroxylamine oxidoreductase (HAO) catalyzes the four-electron oxidation of NH2OH to NO2(-) We provide evidence that HAO oxidizes NH2OH by only three electrons to NO under both anaerobic and aerobic conditions...
July 17, 2017: Proceedings of the National Academy of Sciences of the United States of America
Jiale Wang, Benzhou Gong, Yingmu Wang, Yuhui Wen, Jian Zhou, Qiang He
A simultaneous nitrification and denitrification (SND) process in sequencing batch biofilm reactor (SBBR) was established to treat high carbon and nitrogen saline wastewater in this study. Acetate, glucose and an organic mixture were applied as organic sources in three SBBRs, achieving average total nitrogen removal efficiency of 97.15%, 63.94% and 94.99% during 120days' operation, respectively. The underlying nitrogen removal mechanisms were investigated by 16S rRNA sequencing and batch tests. Results showed different carbon sources had great impact on microbial communities, and led to different nitrogen removal mechanism...
June 26, 2017: Bioresource Technology
Chao Wei, Li Wei, Chunying Li, Dong Wei, Yunfa Zhao
A laboratory-scale biodegradation and electron transfer based on the sulfur metabolism in the integrated (BESI(®)) process was used to treat a saline petrochemical nanofiltration concentrate (NFC). The integrated process consisted of activated sludge sulfate reduction (SR), and sulfide oxidation (SO) reactors, and a biofilm nitrification reactor. During the process, the total removal efficiencies of chemical oxygen demand (COD), ammonia nitrogen, and total nitrogen (TN) were 76.2, 83.8, and 73.1%, respectively...
July 15, 2017: Environmental Science and Pollution Research International
Kyungjin Cho, Minkyu Choi, Dawoon Jeong, Seockheon Lee, Hyokwan Bae
The process performance and microbial niche of anaerobic ammonia oxidation (ANAMMOX) bacteria were compared in two identical bioreactors inoculated with different inoculum sources (i.e., pre-cultured ANAMMOX bacteria: PAB and activated sludge: AS) entrapped in poly(vinyl alcohol)/sodium alginate (PVA/SA) gel beads for a long-term period (i.e., 1.5 years). The start-up period with AS was longer than that with PAB; however, both bioreactors were successfully operated over the long-term with stable ANAMMOX activity...
July 3, 2017: Chemosphere
A Val Del Río, A Stachurski, R Méndez, J L Campos, J Surmacz-Górska, A Mosquera-Corral
The effects of orange azo dye over ammonia oxidizing bacteria (AOB) and anammox bacteria activities were tested. Performed batch tests indicated that concentrations lower than 650 mgorange/L stimulated AOB activity, while anammox bacteria activity was inhibited at concentrations higher than 25 mgorange/L. Long-term performance of a continuous stirred tank reactor (CSTR) for the partial nitritation and a sequencing batch reactor (SBR) for the anammox process was tested in the presence of 50 mgorange/L. In the case of the partial nitritation process, both the biomass concentration and the specific AOB activity increased after 50 days of orange azo dye addition...
July 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Maosheng Zheng, Hui-Zhen Fu, Yuh-Shan Ho
Ammonia oxidation is the rate-limiting and central step in global biogeochemistry cycle of nitrogen. A bibliometric analysis based on 4314 articles extracted from Science Citation Index Expanded database was carried out to provide insights into publication performances and research trends of ammonia oxidation in the period 1991-2014. These articles were originated from a wide range of 602 journals and 95 Web of Science Categories, among which Applied and Environmental Microbiology and Environmental Sciences took the leading position, respectively...
July 13, 2017: Environmental Science and Pollution Research International
Hendrikus J Laanbroek, Peter T M Veenhuizen, Rosalinde M Keijzer, Mariet M Hefting
Bacterial amoA genes had not been detectable by qPCR in freshly sampled Icelandic Andosols thus far. Hence, a new primer set yielding shorter gene fragments has been designed to verify the absence of ammonia-oxidizing bacteria in different Icelandic Andosol classes. At the same time, a new primer set was also constructed for archaeal amoA genes that should improve the quality of PCR products. Although a large part of the soil samples were found to be amoA-negative, bacterial amoA genes were detectable with new as well as old primer sets...
July 13, 2017: Microbial Ecology
Duane Graves, Jacques J Smith, Linxi Chen, Allison Kreinberg, Brianna Wallace, Robby White
Flue gas desulfurization (FGD) is a well-established air treatment technology for coal and oil combustion gases that commonly uses lime or pulverized limestone aqueous slurries to precipitate sulfur dioxide (SO2) as crystalline calcium salts. Under forced oxidation (excess oxygen) conditions, FGD byproduct contains almost entirely (>92%) gypsum (CaSO4·2H2O), a useful and marketable commodity. In contrast, FGD byproduct formed in oxygen deficient oxidation systems contains a high percentage of hannebachite (CaSO3·0...
July 7, 2017: Journal of Environmental Management
Qingxian Su, Chun Ma, Carlos Domingo-Félez, Anne Sofie Kiil, Bo Thamdrup, Marlene Mark Jensen, Barth F Smets
Nitrous oxide (N2O) production from autotrophic nitrogen conversion processes, especially nitritation systems, can be significant, requires understanding and calls for mitigation. In this study, the rates and pathways of N2O production were quantified in two lab-scale sequencing batch reactors operated with intermittent feeding and demonstrating long-term and high-rate nitritation. The resulting reactor biomass was highly enriched in ammonia-oxidizing bacteria, and converted ∼93 ± 14% of the oxidized ammonium to nitrite...
June 24, 2017: Water Research
Chuanqi Zhao, Gang Wang, Xiaochen Xu, Yuesuo Yang, Fenglin Yang
In this study, an oxygen-limiting membrane bioreactor (MBR) with recirculation of biogas for relieving membrane fouling was successfully operated to realize the simultaneous partial nitrification, anammox and denitrification (SNAD) process. The MBR operation was considered effective in the long-term test with total nitrogen (TN) and COD removal efficiencies of 94.86% and 98.91%, respectively. Membrane fouling was significantly alleviated due to the recirculation of biogas and the membrane had been cleaned four times with a normal filtration period of 52 d...
July 6, 2017: Environmental Technology
Yang Huo, Yaohui Bai, Jiuhui Qu
In many highly urbanized areas, effluent from wastewater treatment plants (WWTPs) represents a significant proportion of the water source for receiving rivers. Microbial communities are major components of riverine ecosystems and mediate the processes of nutrients and organic matter produced by treated and untreated WWTP effluent. To date, the impacts of WWTP effluent discharge on riverine microbial communities remain poorly understood. Based on 16S rRNA gene sequencing and water quality analysis, we investigated the microbial community compositions and predicted functions in the effluents of five municipal WWTPs and their receiving rivers...
July 5, 2017: Applied Microbiology and Biotechnology
Xi Li, Miaomiao Zhang, Feng Liu, Liang Chen, Yuyuan Li, Yong Li, Rulin Xiao, Jinshui Wu
Surface flow constructed wetlands (SFCWs) planted with Myriophyllum elatinoides for treatment of swine wastewater were examined to evaluate the effect of season, segment (site S1, S2, and S3), and treatment (100mgL(-1) TN, T1; 300mgL(-1) TN, T2; 500mgL(-1) TN, T3) on the activity, and abundances of nitrifying and, denitrifying microorganisms, and on the abundance of sediment bacteria. The activity and abundances of nitrifiers, denitrifiers, and the abundance of bacteria were the highest in T3 samples, especially in S1 (P<0...
June 20, 2017: Bioresource Technology
Xiaojing Zhang, Nan Zhang, Haoqiang Fu, Tao Chen, Sa Liu, Shuhua Zheng, Jie Zhang
In this study, a membrane bioreactor (MBR) was adopted for completely autotrophic nitrogen removal over nitrite (CANON) process. Zinc oxide nanoparticles (ZnO NPs) was step-wise increased to analyze the influence on nitrogen removal, microbial activity and microbial communities. Finally ZnO NPs was removed to study its recovery capability. The bioactivities of ammonia-oxidizing bacteria (AOB), anaerobic ammonia-oxidizing bacteria (AAOB) and nitrite-oxidizing bacteria (NOB) were detected by batch experiments...
June 15, 2017: Bioresource Technology
Haodong Liu, Chuanlun L Zhang, Chunyan Yang, Songze Chen, Zhiwei Cao, Zhiwei Zhang, Jiwei Tian
Temperature, nutrients, and salinity are among the important factors constraining the distribution and abundance of microorganisms in the ocean. Marine Group II (MGII) belonging to Euryarchaeota commonly dominates the planktonic archaeal community in shallow water and Marine Group I (MGI, now is called Thaumarchaeota) in deeper water in global oceans. Results of quantitative PCR (qPCR) and 454 sequencing in our study, however, showed the dominance of MGII in planktonic archaea throughout the water column of the northeastern South China Sea (SCS) that is characterized by strong water mixing...
2017: Frontiers in Microbiology
Junwon Park, Naoyuki Yamashita, Guangxue Wu, Hiroaki Tanaka
We carried out batch experiments using biomass from a membrane bioreactor (MBR) to study the influence of ammonia oxidizing bacteria (AOB) on the removal of 45 pharmaceuticals and personal care products (PPCPs). Kinetic parameters such as biodegradation constants and adsorption coefficients with and without AOB inhibition were estimated. No significant differences in adsorption tendency were found, but the biodegradability of most compounds was enhanced when ammonia was completely oxidized, indicating that AOB present in MBR played a critical role in eliminating the PPCPs...
June 23, 2017: Science of the Total Environment
Ruijiao Xi, Xi-En Long, Sha Huang, Huaiying Yao
Nitrification inhibitors and urease inhibitors, such as nitrapyrin and N-(n-butyl) thiophosphoric triamide (NBPT), can improve the efficiencies of nitrogen fertilizers in cropland. However, their effects on ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) across different soil pH levels are still unclear. In the present work, vegetable soils at four pH levels were tested to determine the impacts of nitrification and urease inhibitors on the nitrification activities, abundances and diversities of ammonia oxidizers at different pHs by real-time PCR, terminal restriction fragment length polymorphism (T-RFLP) and clone sequence analysis...
December 2017: AMB Express
Qiang Kong, Xiao He, Yu Feng, Ming-Sheng Miao, Qian Wang, Yuan-da Du, Fei Xu
An activated sludge sequencing batch reactor (SBR) was fed with synthetic wastewater containing ofloxacin (OFL) for 52days to study the overall performance of the SBR, the characteristics of extracellular polymeric substances (EPS) and the bacterial community shift. Removal efficiencies of chemical oxygen demand, ammonia nitrogen, phosphorus and OFL were maintained at 90%, 96%, 80% and 65%, respectively. The EPS contents increased with increasing OFL concentration because more EPS was secreted to protect cells from OFL damage...
October 2017: Bioresource Technology
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