# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 7881 | 0 | 1.0000 | Bacterial community shift and antibiotics resistant genes analysis in response to biodegradation of oxytetracycline in dual graphene modified bioelectrode microbial fuel cell. This study explored the biodegradation mechanisms of oxytetracycline (OTC/O) and electrochemical characteristics from the perspective of bacterial community shift and OTC resistance genes in dual graphene modified bioelectrode microbial fuel cell (O-D-GM-BE MFC). In phylum level, Proteobacteria was accounted to 95.04% in O-GM-BA, Proteobacteria and Bacteroidetes were accounted to 59.13% and 20.52% in O-GM-BC, which were beneficial for extracellular electron transport (EET) process and OTC biodegradation. In genus level, the most dominant bacteria in O-GM-BA were Salmonella and Trabulsiella, accounting up to 83.04%, moreover, representative exoelectrogens (Geobacter) were enriched, which contributed to OTC biodegradation and electrochemical performances; abundant degrading bacteria (Moheibacter, Comamonas, Pseudomonas, Dechloromonas, Nitrospira, Methylomicrobium, Pseudorhodoferax, Thiobacillus, Mycobacterium) were enriched in O-GM-BC, which contributed to the maximum removal efficiency of OTC; coding resistance genes of efflux pump, ribosome protective protein and modifying or passivating were all found in O-GM-BE, and this explained the OTC removal mechanisms from gene level. | 2019 | 30640017 |
| 7918 | 1 | 0.9994 | Robustness of the partial nitrification-anammox system exposing to triclosan wastewater: Stress relieved by extracellular polymeric substances and resistance genes. The partial nitrification-anammox (PN/A) process is a promising method for the treatment of municipal wastewater. It is necessary to clarify the responses of PN/A system to antimicrobial agent triclosan (TCS) widely existed in the influent of wastewater treatment plants. In this study, it was found that PN/A system was robust to cope with 0.5 mg/L TCS. Specifically, the control reactor reached 80% total nitrogen removal efficiency (TNRE) on day 107, while the reactor feeding with 0.5 mg/L TCS reached the same TNRE on day 84. The results of the activity test, high-throughput sequencing and DNA-based stable isotope probing showed that 0.5 mg/L TCS did not impede the performance of ammonia oxidizing archaea, ammonia oxidizing bacteria (Nitrosomonas) and anammox bacteria (Candidatus Brocadia and Ca. Kuenenia), but significant inhibited the nitrite oxidizing bacteria (Nitrospira and Ca. Nitrotoga) and denitrifying bacteria. The influent TCS led to the increase of EPS content and enrichment of four resistance genes (RGs) (intI1, sul1, mexB, and tnpA), which might be two principal mechanisms by which PN/A can resist TCS. In addition, functional bacteria carrying multiple RGs also contributed to the maintenance of PN/A system function. These findings improved the understandings of antimicrobial effects on the PN/A system. | 2022 | 34954146 |
| 8044 | 2 | 0.9994 | Effect of tetracycline on nitrogen removal in Moving Bed Biofilm Reactor (MBBR) System. The effect of tetracycline (TC) on nitrogen removal in wastewater treatment plants has become a new problem. This study investigated the effects of TC on nitrogen removal using a Moving Bed Biofilm Reactor system. The results showed that there was no significant effect on nitrogen removal performance when the concentration of TC was 5 mg/L, and that the total nitrogen (TN) removal efficiency could reach 75-77%. However, when the concentration of TC increased to 10 mg/L, the denitrification performance was affected and the TN removal efficiency decreased to 58%. The abundance of denitrifying bacteria such as those in the genus Thauera decreased, and TC-resistant bacteria gradually became dominant. At a TC concentration of 10 mg/L, there were also increases and decreases, respectively, in the abundance of resistance and denitrification functional genes. The inhibitory effect of TC on denitrification was achieved mainly by the inhibition of nitrite-reducing bacteria. | 2022 | 35007308 |
| 7959 | 3 | 0.9994 | Evolution of microbial community and antibiotic resistance genes in anammox process stressed by oxytetracycline and copper. The individual and combined impacts of copper ion (Cu(2+)) and oxytetracycline (OTC) on anaerobic ammonium oxidation (anammox) performance and its self-recovery process were examined. Experimental results showed that the anammox performance and activity of anammox bacteria were inhibited by 1.0 mg L(-1) OTC, Cu(2+) and OTC + Cu(2+), and both single and combined inhibitions were reversible. The abundance of functional genes and parts of antibiotic resistance genes (ARGs) were positively related to the dominant bacterium Ca. Kuenenia, implying that the recovery of the performance was associated with the progressive induction of potentially resistant species after inhibition. The above outcomes illustrated that anammox bacteria were stressed by metals and antibiotics, but they still could remove nitrogen at a rate higher than 20.6 ± 0.8 kg N m(-3) d(-1), providing guidance for engineering applications of anammox processes. | 2021 | 32949830 |
| 8041 | 4 | 0.9994 | Insights into the microalgae-bacteria consortia treating swine wastewater: Symbiotic mechanism and resistance genes analysis. This study investigated the effects of microalgae-bacteria consortia (MBC) (Chlorella pyrenoidosa-activated sludge (AS)) treating swine wastewater with low C/N ratios. After co-culture, the removal rates of NH(4)(+)-N and PO(4)(3-)-P increased by 53.84% and 43.52%. Furthermore, the sulfamethoxazole (SMX) degradation rates in MBC were slightly higher than in the activated sludge process. Interestingly, the absolute abundance of antibiotic resistance genes (ARGs) in effluent from MBC is relatively less than in the AS process. C. pyrenoidosa has a negative zeta potential that allows bacteria to adhere to its surface. The concentrations of carbohydrates and proteins in extracellular polymeric substance (EPS) of MBC dramatically increased compared with the AS process. At the phylum level, Proteobacteria, Bacteroidota, and Cyanobacteria were the main bacteria, while Ascomycota and Basidiomycota were the primary fungi in MBC. Overall, those findings lead to a better understanding of the swine wastewater containing antibiotic treatment by MBC. | 2022 | 35217162 |
| 7915 | 5 | 0.9993 | Deciphering antibiotic resistance genes and microbial community of anammox consortia under sulfadiazine and chlortetracycline stress. The responses of anammox consortia to typical antibiotics sulfadiazine (SDZ) and chlortetracycline (CTC) were evaluated on the aspects of general performance, microbial activity, diversity and abundance of antibiotic resistance genes (ARGs), and microbial host of ARGs in anammox system. Results showed the anammox consortia had a stable performance and great resistance to 10 mg/L of SDZ, while 1 mg/L of CTC induced an unrecoverable inhibitory influence on nitrogen removal performance and anammox activity without any special treatment. The absolute abundances of anammox functional genes (nirS, hzsA and hdh) were stimulated by the acclimation to SDZ stress, however, they were much lower than the initial levels under CTC stress. In anammox consortia, ARGs comprised 18 types (94 subtypes) derived from over 20 genera. Strikingly, the anammox bacteria (AnAOB) "Ca. Brocadia" occupied 46.81% of the SDZ resistance genes (sul1 and sul2) and 38.63% of CTC resistance genes (tetX, tetG and rpsJ), and thus were identified as the dominant antibiotic resistance bacteria (ARB). Therefore, harboring the corresponding ARGs by AnAOB could be the primary protective mechanism to interpret the resistance of anammox consortia to antibiotics stress. Meanwhile, co-occurring of ARGs in anammox consortia suggested the synergistic cooperation of different ARGs could be an essential strategy to alleviate the SDZ and CTC stress. The present study proposed a new interpretation of possible mechanism that cause antibiotic resistance of anammox consortia. | 2022 | 35259594 |
| 7960 | 6 | 0.9993 | Diversity evolution of functional bacteria and resistance genes (CzcA) in aerobic activated sludge under Cd(II) stress. An activated sludge sequencing batch reactor (SBR) was used to treat divalent cadmium (Cd(II)) wastewater for 60 d to investigate the overall treatment performance, evolution of the bacterial community, and abundance of the Cd(II) resistance gene CzcA and shifts in its potential host bacteria. During stable operation with a Cd(II) concentration of 20 mg/L, the average removal efficiencies of Cd(II) and chemical oxygen demand (COD) were more than 85% and that of total phosphorus was greater than 70%, while the total nitrogen (TN) was only about 45%. The protein (PN) content in the extracellular polymeric substances (EPS) increased significantly after Cd(II) addition, while polysaccharides displayed a decreasing trend (p < 0.05), indicating that EPS prefer to release PN to adsorb Cd(II) and protect bacteria from damage. Three-dimensional fluorescence spectral analysis showed that fulvic acid-like substances were the most abundant chemical components of EPS. The addition of Cd(II) adversely affected most denitrifying bacteria (p < 0.05), which is consistent with the low TN removal. In addition, quantitative polymerase chain reaction analysis revealed that CzcA gene abundance decreased as the Cd(II) concentration increased, possibly because expression of the CzcA gene was inhibited by Cd(II) stress. The majority of CzcA gene sequences were carried by Pseudomonas, making it the dominant genus among Cd(II)-resistant bacteria. | 2019 | 31514000 |
| 7958 | 7 | 0.9993 | Microbial response and recovery strategy of the anammox process under ciprofloxacin stress from pure strain and consortia perspectives. Ciprofloxacin (CIP) poses a high risk of resistance development in water environments. Therefore, comprehensive effects and recovery strategies of CIP in anaerobic ammonia oxidation (anammox) process were systematically elucidated from consortia and pure strains perspectives. The anammox consortia was not significantly affected by the stress of 10 mg L(-1) CIP, while the higher concentration (20 mg L(-1)) of CIP caused a dramatic reduction in the nitrogen removal performance of anammox system. Simultaneously, the abundances of dominant functional bacteria and corresponding genes also significantly decreased. Such inhibition could not be mitigated by the recovery strategy of adding hydrazine and hydroxylamine. Reducing nitrogen load rate from 5.1 to 1.4 kg N m(-3) d(-)(1) promoted the restoration of three reactors. In addition, the robustness and recovery of anammox systems was evaluated using starvation and shock strategies. Simultaneously, antibiotic resistance genes and key metabolic pathways of anammox consortia were upregulated, such as carbohydrate and energy metabolisms. In addition, 11 pure stains were isolated from the anammox system and identified through phylogenetic analysis, 40 % of which showed multidrug resistance, especially Pseudomonas. These findings provide deep insights into the responding mechanism of anammox consortia to CIP stress and promote the application of anammox process for treating wastewater containing antibiotics. | 2024 | 38554504 |
| 7968 | 8 | 0.9993 | Induced ciprofloxacin biotransformation and antibiotic-resistance genes control in sulfate-reducing microbial fuel cells: Strategy and mechanism. Ciprofloxacin-containing saline wastewater treatment gains increasing attentions, due to the problems of limited degradation and spreading risk of antibiotic-resistance genes (ARGs). Sulfate reduction is a cost-efficient technology for simultaneous sulfate and antibiotic removal. The microbial fuel cell enhances removal of antibiotics and reduces spreading risk of ARGs in effluents, however, the biotransformation of ciprofloxacin (CIP) in sulfate-reducing microbial fuel cell (SR-MFC) remains unclear. Thus, a SR-MFC is established in this study for treatment of CIP-containing saline wastewater, which achieves simultaneous removal of CIP (50.2%), sulfate (85.1%), and ARGs (17.0%). The Desulfovibrio sp. bacteria become dominant in free biomass (58.8%) and biofilm (73.6%) after CIP exposing, respectively. The CIP can be utilized in prior to lactate for sulfate reduction, while the energy production is initially contributed to sulfate reduction followed by sulfide oxidation. Notably, the expression of ARGs declines probably due to enhanced biotransformation and limited adsorption (2.6%) of CIP on biomass after CIP addition. Long-term exposure to CIP enriches the ARGs of antibiotic efflux pump, implying some CIP is pumped out from intracellular to extracellular. A novel degradation pathway attacking the N15 site in piperazine may be the major and environmental-friendly biotransformation reaction, where the enzyme of ammonia-lyase and acetyltransferase are involved in. To our best knowledge, this is the first report of the novel pathway in bacterial CIP degradation system, which is known as fungal CIP biotransformation pathway. This study provides insights for CIP biotransformation in SR-MFC, and the operational strategy for antibiotic-containing saline wastewater treatment with ARGs control. | 2025 | 40058044 |
| 8043 | 9 | 0.9993 | Effect of tetracycline on bio-electrochemically assisted anaerobic methanogenic systems: Process performance, microbial community structure, and functional genes. Bio-electrochemically assisted anaerobic methanogenic systems (An-BES) are highly effective in wastewater treatment for methane production and degradation of toxic compounds. However, information on the treatment of antibiotic-bearing wastewater in An-BES is still very limited. This study therefore investigated the effect of tetracycline (TC) on the performance, microbial community, as well as functional and antibiotic resistance genes of An-BES. TC at 1 and 5 mg/L inhibited methane production by less than 4.8% compared to the TC-free control. At 10 mg/L TC, application of 0.5 and 1.0 V decreased methane production by 14 and 9.6%, respectively. Under the effect of 1-10 mg/L TC, application of 1.0 V resulted in a decrease of current from 42.3 to 2.8 mA. TC was mainly removed by adsorption; its removal extent increased by 19.5 and 32.9% with application of 0.5 and 1.0 V, respectively. At 1.0 V, current output was not recovered with the addition of granular activated carbon, which completely removed TC by adsorption. Metagenomic analysis showed that propionate oxidizing bacteria and methanogens were more abundant in electrode biofilms than in suspended culture. Antibiotic resistance genes (ARGs) were less abundant in biofilms than in suspended culture, regardless of whether voltage was applied or not. Application of 1.0 V resulted in the enrichment of Geobacter in the anode and Methanobacterium in the cathode. TC inhibited exoelectrogens, propionate oxidizing bacteria, and the methylmalonyl CoA pathway, leading to a decrease of current output, COD consumption, and methane production. These findings deepen our understanding of the inhibitory effect of TC in An-BES towards efficient bioenergy recovery from antibiotic-bearing wastewater, as well as the response of functional microorganisms to TC in such systems. | 2022 | 35533856 |
| 7951 | 10 | 0.9993 | Proliferation of antibiotic resistance genes in microbial consortia of sequencing batch reactors (SBRs) upon exposure to trace erythromycin or erythromycin-H2O. A variety of antibiotics and their metabolites at sub-inhibitory level concentrations are suspected to expand resistance genes in the environment. However, knowledge is limited on the causal correlation of trace antibiotics or their metabolites with resistance proliferation. In this study, erythromycin (ERY) resistance genes were screened on microbial consortia of sequencing batch reactors (SBRs) after one year acclimation to ERY (100 μg/L) or dehydrated erythromycin (ERY-H(2)O, 50 μg/L). The identified esterase gene ereA explains that ERY could be degraded to six products by microbes acclimated to ERY (100 μg/L). However, ERY could not be degraded by microbes acclimated to ERY-H(2)O (50 μg/L), which may be due to the less proliferated ereA gene. Biodegradation of ERY required the presence of exogenous carbon source (e.g., glucose) and nutrients (e.g., nitrogen, phosphorus) for assimilation, but overdosed ammonium-N (>40 mg/L) inhibited degradation of ERY. Zoogloea, a kind of biofilm formation bacteria, became predominant in the ERY degradation consortia, suggesting that the input of ERY could induce biofilm resistance to antibiotics. Our study highlights that lower μg/L level of ERY or ERY-H(2)O in the environment encourages expansion of resistance genes in microbes. | 2011 | 21482429 |
| 7886 | 11 | 0.9993 | Resistance of anammox granular sludge to copper nanoparticles and oxytetracycline and restoration of performance. Nanoparticles and antibiotics, the two most frequently detected emerging pollutants from different wastewater sources, are eventually discharged into wastewater treatment plants. In this study, the widely used materials CuNPs and oxytetracycline (OTC) were selected as target pollutants to investigate their joint effects on anaerobic ammonium oxidation (anammox). The results indicated that the environmental concentration slightly inhibited the performance of the reactors, while the performance rapidly deteriorated within a week under high-level combined shocks (5.0 mg L(-1) CuNPs and 2.0 mg L(-1) OTC). After the second shock (2.5 mg L(-1) CuNPs and 2.0 mg L(-1) OTC), the resistance of anammox bacteria was enhanced, with an elevated relative abundance of Candidatus Kuenenia and absolute abundance of hzsA, nirS, and hdh. Moreover, the extracellular polymeric substance (EPS) content and specific anammox activity (SAA) showed corresponding changes. Improved sludge resistance was observed with increasing CuNP and OTC doses, which accelerated the recovery of performance. | 2020 | 32244076 |
| 8541 | 12 | 0.9993 | Insights into the response of anammox process to oxytetracycline: Impacts of static magnetic field. The long-term effects of oxytetracycline (OTC) with a high concentration on the anaerobic ammonium oxidation (Anammox) process were evaluated, and the role of static magnetic field (SMF) was further explored. The stress of OTC at 50 mg/L had little effect on the nitrogen removal of anammox process at the first 16 days. With the continuous addition of OTC and the increase of nitrogen loading, the OTC inhibited the nitrogen removal and anammox activity severely. During the 32 days of recovery period without OTC addition, the nitrogen removal was further deteriorated, indicating the inhibition of OTC on anammox activity was irreversible and persistent. The application of SMF alleviated the inhibition of OTC on anammox to some extent, and the specific anammox activity was enhanced by 47.1% compared to the system without SMF during the OTC stress stage. Antibiotic efflux was the major resistance mechanism in the anammox process, and tetA, tetG and rpsJ were the main functional antibiotic resistance genes. The addition of OTC weakened the metabolic interactions between the anammox bacteria and the symbiotic bacteria involved in the metabolism of cofactors and secondary metabolites, leading to the poor anammox activity. The adaptability of microbes to the OTC stress was improved by the application of SMF, which can enhance the metabolic pathways related to bacterial growth and resistance to environmental stress. | 2023 | 37586490 |
| 7967 | 13 | 0.9993 | Ciprofloxacin degradation in anaerobic sulfate-reducing bacteria (SRB) sludge system: Mechanism and pathways. Ciprofloxacin (CIP), a fluoroquinolone antibiotic, removal was examined for the first time, in an anaerobic sulfate-reducing bacteria (SRB) sludge system. About 28.0% of CIP was biodegraded by SRB sludge when the influent CIP concentration was 5000 μg/L. Some SRB genera with high tolerance to CIP (i.e. Desulfobacter), were enriched at CIP concentration of 5000 μg/L. The changes in antibiotic resistance genes (ARGs) of SRB sludge coupled with CIP biodegradation intermediates were used to understand the mechanism of CIP biodegradation for the first time. The percentage of efflux pump genes associated with ARGs increased, while the percentage of fluoroquinolone resistance genes that inhibit the DNA copy of bacteria decreased during prolonged exposure to CIP. It implies that some intracellular CIP was extruded into extracellular environment of microbial cells via efflux pump genes to reduce fluoroquinolone resistance genes accumulation caused by exposure to CIP. Additionally, the degradation products and the possible pathways of CIP biodegradation were also examined using the new method developed in this study. The results suggest that CIP was biodegraded intracellularly via desethylation reaction in piperazinyl ring and hydroxylation reaction catalyzed by cytochrome P450 enzymes. This study provides an insight into the mechanism and pathways of CIP biodegradation by SRB sludge, and opens-up a new opportunity for the treatment of CIP-containing wastewater using sulfur-mediated biological process. | 2018 | 29494897 |
| 7914 | 14 | 0.9992 | Response of partial nitrification sludge to the single and combined stress of CuO nanoparticles and sulfamethoxazole antibiotic on microbial activity, community and resistance genes. Considering the inevitable release of antibiotics and nanoparticles (NPs) into the nitrogen containing wastewater, the combined impact of CuO NPs and sulfamethoxazole (SMX) antibiotic on partial nitrification (PN) process was investigated in four identical reactors. Results showed that the bioactivity of the aerobic ammonia-oxidizing bacteria (AOB) decreased by half after they were exposed to the combination of CuO NPs and SMX for short-term; however, there was no obvious variation in the bioactivity of AOB when they were exposed to either CuO NPs or SMX. During long-term exposure, the ammonia removal efficiency (ARE) of CuO NPs improved whereas that of SMX decreased, while the combination of CuO NPs and SMX significantly decreased ARE from 62.9% (in control) to 38.2% and had an unsatisfactory self-recovery performance. The combination of CuO NPs and SMX significantly changed the composition of microbial community, decreased the abundance of AOB, and significantly suppressed PN process. Reegarding the resistance genes, the CuO NPs-SMX combination did not improve the expression of copA, cusA, sul1 and sul2; however, it significantly induced the expression of sul3 and sulA. | 2020 | 32050397 |
| 7902 | 15 | 0.9992 | Determination of the lower limits of antibiotic biodegradation and the fate of antibiotic resistant genes in activated sludge: Both nitrifying bacteria and heterotrophic bacteria matter. Antibiotics can be biodegraded in activated sludge via co-metabolism and metabolism. In this study, we investigated the biodegradation pathways of sulfamethoxazole (SMX) and antibiotic resistant genes' (ARGs) fate in different autotrophic and heterotrophic microorganisms, by employing aerobic sludge, mixed sludge, and nitrifying sludge. A threshold concentration of SMX activating the degradation pathways in the initial stage of antibiotics degradation was found and proved in different activated sludge systems. Heterotrophic bacteria played an important role in SMX biodegradation. However, ammonia-oxidizing bacteria (AOB) had a faster metabolic rate, which was about 15 times higher than heterotrophic bacteria, contributing much to SMX removal via co-metabolism. As SMX concentration increases, the amoA gene and AOB relative abundance decreased in aerobic sludge due to the enrichment of functional heterotrophic bacteria, while it increased in nitrifying sludge. Microbial community analysis showed that functional bacteria which possess the capacity of SMX removal and antibiotic resistance were selected by SMX pressure. Potential ARGs hosts could increase their resistance to the biotoxicity of SMX and maintain system performance. These findings are of practical significance to guide antibiotic biodegradation and ARGs control in wastewater treatment plants. | 2022 | 34799165 |
| 7919 | 16 | 0.9992 | Bioaugmentation using HN-AD consortia for high salinity wastewater treatment: Synergistic effects of halotolerant bacteria and nitrogen removal bacteria. Bioaugmentation shows promise in enhancing nitrogen removal efficiency of high-salt wastewater, yet the impact of microbial associations on ecosystem function and community stability remains unclear. This study innovatively introduced a novel heterotrophic nitrification-aerobic denitrification bacterial consortium to improve the performance of SBR reactor for removing nitrogen from saline wastewater. The results revealed that the bioaugmented reactor (R2) exhibited superior removal performance, achieving maximum removal efficiencies of 87.8 % for COD and 97.8 % for NH(4)(+)-N. Moreover, proper salinity (2 % and 4 %) promoted the secretion of EPS and ectoine, further enhancing the resistance and stability of bacterial consortia. 16S rRNA gene sequencing and metagenomics analysis revealed the key denitrifying bacteria Pseudomonas and salt-tolerant bacteria Halomonas were successfully coexistence and the relative abundances of crucial genes (napB, nirS, norB, norC and nosZ) were increased obviously, which were benefit for the excellent nitrogen removal performance in R2. These findings elucidate microbial interactions in response to salinity in bioaugmentation, providing a valuable reference for the efficient treatment of high-saline wastewater. | 2025 | 40233618 |
| 7888 | 17 | 0.9992 | Microecology of aerobic denitrification system construction driven by cyclic stress of sulfamethoxazole. The construction of aerobic denitrification (AD) systems in an antibiotic-stressed environment is a serious challenge. This study investigated strategy of cyclic stress with concentration gradient (5-30 mg/L) of sulfamethoxazole (SMX) in a sequencing batch reactor (SBR), to achieve operation of AD. Total nitrogen removal efficiency of system increased from about 10 % to 95 %. Original response of abundant-rare genera to antibiotics was changed by SMX stress, particularly conditionally rare or abundant taxa (CRAT). AD process depends on synergistic effect of heterotrophic nitrifying aerobic denitrification bacteria (Paracoccus, Thauera, Hypomicrobium, etc). AmoABC, napA, and nirK were functionally co-expressed with multiple antibiotic resistance genes (ARGs) (acrR, ereAB, and mdtO), facilitating AD process. ARGs and TCA cycling synergistically enhance the antioxidant and electron transport capacities of AD process. Antibiotic efflux pump mechanism played an important role in operation of AD. The study provides strong support for regulating activated sludge to achieve in situ AD function. | 2024 | 38710419 |
| 8042 | 18 | 0.9992 | Algal-bacterial consortium mediated system offers effective removal of nitrogen nutrients and antibiotic resistance genes. The sulfonamide antibiotic resistance genes (ARGs) especially sul1 was identified as the dominant in eutrophic water. The performance of Chlorella vulgaris-B. licheniformis consortium toward sul1 removal, total nitrogen (TN) removal, and the mechanism of sul1 removal was investigated. The removal efficiency of exogenous ARGs plasmids carrying sul1 reached (97.2 ± 2.3)%. The TN removal rate reached (98.5 ± 1.2)%. The enhancements of carbon metabolism, nitrogen metabolism, aminoacyl-tRNA biosynthesis, and glycoproteins had significant influences on sul1 and TN removals, under the premise of normal growth of algae and bacteria. The quantitative polymerase chain reaction (qPCR) results suggested that the absolute abundances of sul1 were low in algal-bacterial systems (0 gene copies/mL) compared with individual systems ((1 × 10(6) ± 15) gene copies/mL). The duplication of sul1 was inhibited in algal cells and bacterial cells. The algal-bacterial consortium seems to be a promising technology for wastewater treatment with a potential to overcome the eutrophication and ARGs challenges. | 2022 | 36049708 |
| 7969 | 19 | 0.9992 | Metagenomic insights into the influence of pH on antibiotic removal and antibiotic resistance during nitritation: Regulations on functional genus and genes. The changes in pH and the resulting presence of free nitrous acid (FNA) or free ammonia (FA) often inhibit antibiotic biodegradation during nitritation. However, the specific mechanisms through which pH, FNA and FA influence antibiotic removal and the fate of antibiotic resistance genes (ARGs) are not yet fully understood. In this study, the effects of pH, FNA, and FA on the removal of cefalexin and amoxicillin during nitritation were investigated. The results revealed that the decreased antibiotic removal under both acidic condition (pH 4.5) and alkaline condition (pH 9.5) was due to the inhibition of the expression of amoA in ammonia-oxidizing bacteria and functional genes (hydrolase-encoding genes, transferase-encoding genes, lyase-encoding genes, and oxidoreductase-encoding genes) in heterotrophs. Furthermore, acidity was the primary inhibitor of antibiotic removal at pH 4.5, followed by FNA. Antibiotic removal was primarily inhibited by alkalinity at pH 9.5, followed by FA. The proliferation of ARGs mediated by mobile genetic element was promoted under both acidic and alkaline conditions, attributed to the promotion of FNA and FA, respectively. Overall, this study highlights the inhibitory effects of acidity and alkalinity on antibiotic removal during nitritation. | 2024 | 39068965 |