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Ammonia oxidizing bacteria

Nicole Y Lee, Omer Ibrahim, Shilpi Khetarpal, Mariya Gaber, Spiros Jamas, Ioannis Gryllos, Jeffrey S Dover
Keratosis pilaris (KP) is a common skin finding that presents as follicular hyperkeratotic papules on the proximal extremities in patients with a propensity for atopy. Although often asymptomatic, the stippled appearance is cosmetically disturbing to patients and difficult to treat as current therapies are limited in availability and efficacy. Nitric oxide (NO) has been found to be essential in basic systemic and cutaneous physiologic function, specifically in terms of its anti-microbial and anti-inflammatory properties, which evolutionarily was maintained by ammonia-oxidizing bacteria (AOB)...
March 1, 2018: Journal of Drugs in Dermatology: JDD
Mingwei Cai, Siu-Kin Ng, Chee Kent Lim, Hongyuan Lu, Yangyang Jia, Patrick K H Lee
Nitrification plays a crucial role in global nitrogen cycling and treatment processes. However, the relationships between the nitrifier guilds of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) are still poorly understood, especially in freshwater habitats. This study examined the physiological interactions between the AOB and NOB present in a freshwater aquarium biofilter by culturing them, either together or separately, in a synthetic medium. Metagenomic and 16S rRNA gene sequencing revealed the presence and the draft genomes of Nitrosomonas -like AOB as well as Nitrobacter -like NOB in the cultures, including the first draft genome of Nitrobacter vulgaris ...
2018: Frontiers in Microbiology
Wan Yang, Shilong He, Ming Han, Bingbing Wang, Qigui Niu, Yujia Xu, Yi Chen, Haibo Wang
In this study, the nitrogen removal performance and microbial community structure were investigated during the start-up, instability, and recovery stages of an anaerobic ammonium oxidation (anammox) reactor loaded with compound carriers (shale ceramsite and suspended ball carrier). The results indicated that the anammox reactor successfully started up on 116th d when the nitrogen loading rate (NLR) reached 0.72 ± 0.05 kg N m-3  d-1 . The anammox reactor ran well with free ammonia (FA) at 13.65 ± 2...
March 10, 2018: Journal of Bioscience and Bioengineering
P Kuntke, T H J A Sleutels, M Rodríguez Arredondo, S Georg, S G Barbosa, A Ter Heijne, Hubertus V M Hamelers, C J N Buisman
In recent years, (bio)electrochemical systems (B)ES have emerged as an energy efficient alternative for the recovery of TAN (total ammonia nitrogen, including ammonia and ammonium) from wastewater. In these systems, TAN is removed or concentrated from the wastewater under the influence of an electrical current and transported to the cathode. Subsequently, it can be removed or recovered through stripping, chemisorption, or forward osmosis. A crucial parameter that determines the energy required to recover TAN is the load ratio: the ratio between TAN loading and applied current...
March 9, 2018: Applied Microbiology and Biotechnology
(no author information available yet)
The nitritation-anammox process is an efficient and cost-effective approach for biological nitrogen removal, but its application in treating mainstream wastewater remains a great challenge. Mainstream nitritation-anammox processes could create opportunities for achieving energy self-sufficient or energy-generating wastewater treatment plants. Significant advancements have been achieved via pilot- and full-scale trials to overcome the major obstacles under mainstream conditions, such as repression of nitrite-oxidizing bacteria, limiting the overgrowth of denitrifiers, and effective selection and retention of ammonia-oxidizing bacteria and anammox bacteria...
March 8, 2018: Water Environment Research: a Research Publication of the Water Environment Federation
Alejandro Palomo, Anders G Pedersen, S Jane Fowler, Arnaud Dechesne, Thomas Sicheritz-Pontén, Barth F Smets
The description of comammox Nitrospira spp., performing complete ammonia-to-nitrate oxidation, and their co-occurrence with canonical β-proteobacterial ammonia oxidizing bacteria (β-AOB) in the environment, calls into question the metabolic potential of comammox Nitrospira and the evolutionary history of their ammonia oxidation pathway. We report four new comammox Nitrospira genomes, constituting two novel species, and the first comparative genomic analysis on comammox Nitrospira. Unlike canonical Nitrospira, comammox Nitrospira genomes lack genes for assimilatory nitrite reduction, suggesting that they have lost the potential to use external nitrite nitrogen sources...
March 7, 2018: ISME Journal
Holger Daims, Michael Wagner
In this infographic, the key metabolic functions of Nitrospira and the role that these bacteria play in nitrification and other processes in the environment is shown. Nitrospira plays pivotal roles in nitrification as an aerobic chemolithoautotrophic nitrite-oxidizing bacterium. These bacteria often occur in close association with ammonia-oxidizing bacteria or archaea that convert ammonia to nitrite, which is further oxidized to nitrate by Nitrospira. However, in 'reciprocal feeding' interactions, Nitrospira can also provide ammonia oxidizers with ammonia released from urea or cyanate, which is further nitrified as described above...
February 28, 2018: Trends in Microbiology
Xiaojing Zhang, Yue Zhou, Siyu Zhao, Rongrong Zhang, Zhaoxue Peng, Hanfei Zhai, Hongzhong Zhang
In this study, the effect of Fe (II) on Anaerobic Ammonium Oxidation (ANAMMOX) process was investigated by step-wise increasing the Fe (II) in influent from 1 to 50 mg L-1 . The nitrogen removal, biofilm property and the microbial community were analyzed in each phase. Results showed that, the anaerobic ammonia-oxidizing bacteria (AAOB) bioactivity and the nitrogen removal of ANAMMOX system were slightly improved to 0.58 from the initial 0.51 kg m-3 d-1 by Fe (II) in 1-5 mg L-1 . The nitrogen removal was suppressed and could recover to the initial level during the same period under 10-20 mg L-1 Fe (II), while it did not recover to the initial level under 30 mg L-1 Fe (II) and showed no recovery performance under 50 mg L-1 Fe (II)...
February 22, 2018: Chemosphere
Chenyuan Dang, Wen Liu, Yaxuan Lin, Maosheng Zheng, Huan Jiang, Qian Chen, Jinren Ni
Surface sediments are the inner source of contaminations in aquatic systems and usually maintain aerobic conditions. As the key participators of nitrification process, little is known about the activities and contributions of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in the surface sediments. In this study, we determined the net and potential nitrification rates and used 1-octyne as an AOB specific inhibitor to detect the contributions of AOA and AOB to nitrification in surface sediments of Danjiangkou reservoir, which is the water source area of the middle route of South-to-North Water Diversion Project in China...
March 1, 2018: Applied Microbiology and Biotechnology
Junjie Liu, Zhenhua Yu, Qin Yao, Yueyu Sui, Yu Shi, Haiyan Chu, Caixian Tang, Ashley E Franks, Jian Jin, Xiaobing Liu, Guanghua Wang
Black soils (Mollisols) of northeast China are highly productive and agriculturally important for food production. Ammonia-oxidizing microbes play an important role in N cycling in the black soils. However, the information related to the composition and distribution of ammonia-oxidizing microbes in the black soils has not yet been addressed. In this study, we used the amoA gene to quantify the abundance and community composition of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) across the black soil zone...
2018: Frontiers in Microbiology
Xiang Li, Yong Huang, Heng-Wei Liu, Chuan Wu, Wei Bi, Yi Yuan, Xin Liu
In recent years, there have been a number of reports on the phenomenon in which ferric iron (Fe(III)) is reduced to ferrous iron [Fe(II)] in anaerobic environments, accompanied by simultaneous oxidation of ammonia to NO2 - , NO3 - , or N2. However, studies on the relevant reaction characteristics and mechanisms are rare. Recently, in research on the effect of Fe(III) on the activity of Anammox sludge, excess ammonia oxidization has also been found. Hence, in the present study, Fe(III) was used to serve as the electron acceptor instead of NO2 - , and the feasibility and characteristics of Anammox coupled to Fe(III) reduction (termed Feammox) were investigated...
February 2018: Journal of Environmental Sciences (China)
Hang Liu, Yongkui Yang, Huifang Sun, Lin Zhao, Yu Liu
The presence of antibiotics in wastewater has raised serious concerns about its potential impacts on biological nitrogen and phosphorus (N&P) removal. This study investigated the long-term process performance and microbial structures in response to tetracycline in the enhanced N&P removal process. Results showed that trace tetracycline (20 and 50 μg/L) had no obvious effect on the N&P removal, while the relative abundances of Nitrospira and poly-phosphate accumulating organisms (PAOs) were found to increase...
February 13, 2018: Bioresource Technology
A Castellano-Hinojosa, P Maza-Márquez, Y Melero-Rubio, J González-López, B Rodelas
Ammonia-oxidizing bacteria (AOB), ammonia oxidizing archaea (AOA) and N2 O-reducing denitrifiers were measured by quantitative real-time PCR (qPCR) in activated sludge samples from four full-scale wastewater treatment plants (WWTPs) in South Spain, and their abundances were linked to the generation of N2 O in the samples using multivariate analysis (Non-metric multidimensional scaling, MDS, and BIO-ENV). The average abundances of AOA remained in similar orders of magnitude in all WWTPs (106 copies amoA/L activated sludge mixed liquor), while significant differences were detected for AOB (105 -109 copies amoA/L) and N2 O-reducers (107 -1010 copies nosZ/L)...
February 19, 2018: Chemosphere
Zsuzsanna Nagymáté, Katalin Nemes-Barnás, Gergely Krett, Károly Márialigeti
This study provides a comprehensive microbiological survey of three drinking water networks applying different water treatment processes. Variability of microbial communities was assessed by cultivation-based [nitrifying, denitrifying most probable number (MPN) heterotrophic plate count] and sequence-aided terminal restriction fragment length polymorphism (T-RFLP) analysis. The effect of microbial community composition on nitrifying MPN values was revealed. The non-treated well water samples showed remarkable differences to their corresponding distribution systems regarding low plate count, nitrifying MPN, and the composition of microbial communities, which increased and changed, respectively, in distribution systems...
February 23, 2018: Acta Microbiologica et Immunologica Hungarica
Minkyu Choi, Kyungjin Cho, Dawoon Jeong, Yun-Chul Chung, Joonhong Park, Seockheon Lee, Hyokwan Bae
In this study, the effects of the ammonium loading rate (ALR) and inorganic carbon loading rate (ILR) on the nitrification performance and composition of a nitrifying bacterial community were investigated in a moving bed biofilm reactor, using poly(vinyl alcohol) (PVA) sponge cubes as a supporting carrier. Between the two ALRs of 0.36 and 2.16 kg-N m-1 d-1 , stable partial nitritation was achieved at the higher ALR. Inorganic carbon was dosed at high levels: 33.1, 22.0, 16.4, 11.0, and 5.4 times the theoretical amount...
February 22, 2018: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
Chih-Yu Chen, Teh-Hua Tsai, Chih-Hao Chang, Chih-Fang Tseng, Shih-Yun Lin, Ying-Chien Chung
The effectiveness of an airlift reactor system in simultaneously removing hydrogen sulfide (H2 S) and ammonia (NH3 ) from synthetic and actual waste gases was investigated. The effects of various parameters, including the ratio of inoculum dilution, the gas concentration, the gas retention time, catalyst addition, the bubble size, and light intensity, on H2 S and NH3 removal were investigated. The results revealed that optimal gas removal could be achieved by employing an activated inoculum, using a small bubble stone, applying reinforced fluorescent light, adding Fe2 O3 catalysts, and applying a gas retention time of 20 s...
February 21, 2018: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
Lei Yan, Guoxing Wang, Shiqi Ai, Zhaochen Huo, Yanjie Wang, Ji-Dong Gu, Weidong Wang
Composting of cattle manure was conducted under four ventilation strategies, i.e., no-aeration (A-00), continuous aeration (B-44), non-aeration for 14 d and then aeration for 42 d (C-04), aeration for 14 d and then no-aeration for 42 d (D-40). Physicochemical parameters and potential ammonia oxidation (PAO) indicated that continuous and intermittent ventilation provide favourable conditions for ammonia-oxidizing bacteria (AOB) and archaea (AOA) to oxidize ammonia. Quantitative PCR (qPCR) analysis showed AOB amoA gene abundance of all treatments on every sampling day ranged from 2...
February 16, 2018: Journal of Environmental Management
Hui He, Yu Zhen, Tiezhu Mi, Lulu Fu, Zhigang Yu
Ammonia oxidation plays a significant role in the nitrogen cycle in marine sediments. Ammonia-oxidizing archaea (AOA) and bacteria (AOB) are the key contributors to ammonia oxidation, and their relative contribution to this process is one of the most important issues related to the nitrogen cycle in the ocean. In this study, the differential contributions of AOA and AOB to ammonia oxidation in surface sediments from adjacent waters of Rushan Bay were studied based on the ammonia monooxygenase ( amoA ) gene...
2018: Frontiers in Microbiology
Petra Bukovská, Michael Bonkowski, Tereza Konvalinková, Olena Beskid, Martina Hujslová, David Püschel, Veronika Řezáčová, María Semiramis Gutiérrez-Núñez, Milan Gryndler, Jan Jansa
Arbuscular mycorrhizal (AM) fungi can significantly contribute to plant nitrogen (N) uptake from complex organic sources, most likely in concert with activity of soil saprotrophs and other microbes releasing and transforming the N bound in organic forms. Here, we tested whether AM fungus (Rhizophagus irregularis) extraradical hyphal networks showed any preferences towards certain forms of organic N (chitin of fungal or crustacean origin, DNA, clover biomass, or albumin) administered in spatially discrete patches, and how the presence of AM fungal hyphae affected other microbes...
February 17, 2018: Mycorrhiza
Xianlei Cai, Ling Yao, Qiyue Sheng, Luyao Jiang, Randy A Dahlgren, Ting Wang
Bacterial communities of biofilms growing on artificial substrates were examined at two time periods (7 and 14 days) and two locations (lentic and lotic areas) in a hypereutrophic urban river of eastern China. Previous studies in this river network indicated that variations of microbial communities were the major factor affecting the distribution of antibiotic resistant genes highlighting the importance of understanding controls of microbial communities. Bacterial communities associated with biofilms were determined using epifluorescence microscopy and high-throughput sequencing...
February 16, 2018: AMB Express
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