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Ding X, Yu Q, Ren H, Geng J. Degradation of conjugated estrogen in visible light-driven intimately coupled photocatalysis and biodegradation system. BIORESOURCE TECHNOLOGY 2024; 406:131045. [PMID: 38942213 DOI: 10.1016/j.biortech.2024.131045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Revised: 06/13/2024] [Accepted: 06/24/2024] [Indexed: 06/30/2024]
Abstract
Visible light-driven intimately coupled photocatalysis and biodegradation (VDICPB) is an efficient technology for removing recalcitrant contaminants, but the degradation pathway on 17β-estradiol 3-Sulfate (E2-3S) is still not clear. In this study, VDICPB based on N-doped TiO2 as a photocatalyst was established to investigate the removal and transformation of E2-3S in synthetic wastewater. VDICPB showed a satisfactory removal efficiency of 97.8 ± 0.4 %, which was much higher than that of independent photocatalysis (84.0 ± 2.2 %) or biodegradation system (71.4 ± 1.8 %). Steroid C/D-rings of E2-3S was broken in VDICPB since the transformation process reached terminal central pathway. Primary metabolites did not accumulate in VDICPB, resulting in a low expression of functional genes. E2-3S was mainly removed by cooperative interaction of photocatalysis and co-metabolism of biofilm. Photocatalysis led to deconjugation and microbes acted to mineralization. This study provides technical reference and theoretical support for the removal of new pollutants.
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Affiliation(s)
- Xiangwei Ding
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Qingmiao Yu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400044, China.
| | - Hongqiang Ren
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, China.
| | - Jinju Geng
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400044, China.
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2
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Mustafa A, Azim MK, Laraib Q, Rehman QMU. Hybrid constructed wetlands and filamentous fungi for treatment of mixed sewage and industrial effluents. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:44230-44243. [PMID: 38941051 DOI: 10.1007/s11356-024-34037-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 06/15/2024] [Indexed: 06/29/2024]
Abstract
Developing countries face multifaceted problems of water pollution and futile measures to combat water pollution. This study was conducted to explore the potential application of sustainable nature-based solutions, hybrid constructed wetlands, and the application of filamentous fungi to treat polluted river water that receives sewage and industrial wastewater. A pilot-scale hybrid constructed wetland design comprising two types of floating plants in distinct tanks along with a floating wetland and a free-water surface wetland connected in series was commissioned and tested. The system successfully removed organic pollution (BOD 94% and COD 90%), nutrients (NH4-N and NO3-N 67% and PO4-P 81%), and heavy metals (Cr 75%, Ni 56%, and Fe 79%) in 40 h and showed a high buffering capacity to cope with the varying pollutant loads. Metagenomics analysis of treated and untreated samples of river water revealed a diversified spatial bacterial community with ~ 25% sequences related to sulfur-metabolizing bacteria, genus Sulfuricurvum. The application of an immobilized strain of A. niger as a mycoremediation technique was also tested. It successfully removed pollutants in the combined sewage and industrial wastewater present in river water: COD (96%), TSS (97%), NH4-N (65%), NO3-N (67%), and PO4-P (78%). This study demonstrated that hybrid constructed wetlands and mycoremediation can be used as sustainable wastewater treatment options in the local context and also in developing countries where most of the conventional wastewater treatment plants do not operate.
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Affiliation(s)
- Atif Mustafa
- Department of Environmental Engineering, NED University of Engineering and Technology, Karachi, 75270, Pakistan.
| | - Muhammad Kamran Azim
- Department of Biosciences, Mohammad Ali Jinnah University, Karachi, 75400, Pakistan
| | - Qandeel Laraib
- Department of Biosciences, Mohammad Ali Jinnah University, Karachi, 75400, Pakistan
| | - Qazi Muneeb Ur Rehman
- Department of Environmental Engineering, NED University of Engineering and Technology, Karachi, 75270, Pakistan
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3
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Han J, Jia J, Hu X, Sun L, Ulbricht M, Lv L, Ren Z. Effect of magnetic field coupled magnetic biochar on membrane bioreactor efficiency, membrane fouling mitigation and microbial communities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 931:172549. [PMID: 38643881 DOI: 10.1016/j.scitotenv.2024.172549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 04/15/2024] [Accepted: 04/15/2024] [Indexed: 04/23/2024]
Abstract
The excitation by magnetic field was established to mitigate the membrane fouling of magnetic biochar (MB)-supplemented membrane bioreactor (MBR) in this study. The results showed that the transmembrane pressure (TMP) increase rates decreased by about 8 % after introducing the magnetic field compared with the magnetic biochar-MBR (MB-MBR). Membrane characterization suggested that the flocs in the magnetic field-magnetic biochar-MBR (MF-MB-MBR) formed a highly permeable developed cake layer, and a fluffier and more porous deposited layer on membrane surface, which minimized fouling clogging of the membrane pores. Further mechanistic investigation revealed that the decrease in contact angle of fouled membrane surface in MF-MB-MBR, i.e. an enhanced membrane hydrophilicity, is considered important for forming highly permeable layers. Additionally, the magnetic field was demonstrated to have a positive effect on the improvement of the magneto-biological effect, the enhancement of charge neutralization and adsorption bridging between sludge and magnetic biochar, and the reduction of formation of extracellular polymeric substances (EPSs), which all yielded sludge flocs with a large pore structure conducive to form a fluffy and porous deposited layer in the membrane surface. Furthermore, high-throughput sequencing analysis revealed that the magnetic field also led to a reduction in microbial diversity, and that it promoted the enrichment of specific functional microbial communities (e.g. Bacteroidetes and Firmicutes) playing an important role in mitigating membrane fouling. Taken together, this study of magnetic field-enhanced magnetic biochar for MBR membrane fouling mitigation provides insights important new ideas for more effective and sustainable operation strategies.
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Affiliation(s)
- Jinlong Han
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China
| | - Jianna Jia
- Tianjin Research Institute for Water Transport Engineering, M.O.T., China
| | - Xiangjia Hu
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China; Wuqing District Environmental Protection Bureau, Tianjin, 301700, China
| | - Li Sun
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China.
| | - Mathias Ulbricht
- Lehrstuhl für Technische Chemie II and Center for Envirommental Research (ZWU), Universität Duisburg-Essen, 45117 Essen, Germany
| | - Longyi Lv
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China
| | - Zhijun Ren
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China.
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Zheng S, Lin T, Chen H, Zhang X, Jiang F. Impact of changes in biofilm composition response following chlorine and chloramine disinfection on nitrogenous disinfection byproduct formation and toxicity risk in drinking water distribution systems. WATER RESEARCH 2024; 253:121331. [PMID: 38377929 DOI: 10.1016/j.watres.2024.121331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/17/2024] [Accepted: 02/16/2024] [Indexed: 02/22/2024]
Abstract
In practical drinking water treatment, chlorine and chloramine disinfection exhibit different mechanisms that affect biofilm growth. This study focused on the influence of biofilm composition changes, especially extracellular polymeric substance (EPS) fractions, on the potential formation and toxicity of nitrogenous disinfection by-products (N-DBP). Significant differences in microbial diversity and community structure were observed between the chlorine and chloramine treatments. Notably, the biofilms from the chloramine-treated group had higher microbial dominance and greater accumulation of organic precursors, as evidenced by the semi-quantitative confocal laser-scanning microscopy assay of more concentrated microbial aggregates and polysaccharide proteins in the samples. Additionally, the chloramine-treated group compared with chlorine had a higher EPS matrix content, with a 13.5 % increase in protein. Furthermore, the protein distribution within the biofilm differed; in the chlorine group, proteins were concentrated in the central region, whereas in the chloramine group, proteins were primarily located at the water-biofilm interface. Notably, functional prediction analyses of protein fractions in biofilms revealed specific functional regulation patterns and increased metabolism-related abundance of proteins in the chlorine-treated group. This increase was particularly pronounced for proteins such as dehydrogenases, reductases, transcription factors, and acyl-CoA dehydrogenases. By combining the Fukui function and density functional calculations to further analyse the effect of biofilm component changes on N-DBP production under chlorine/chloramine and by assessing the toxicity risk potential of N-DBP, it was determined that chloramine disinfection is detrimental to biofilm control and the accumulation of protein precursors has a higher formation potential of N-DBPs and toxicity risk, increasing the health risk of drinking water.
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Affiliation(s)
- Songyuan Zheng
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Tao Lin
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China.
| | - Han Chen
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Xue Zhang
- Suzhou Water Supply Company, Suzhou 215002, China
| | - Fuchun Jiang
- Suzhou Water Supply Company, Suzhou 215002, China
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Zheng S, Lin T, Zhang X, Jiang F. Response mechanisms of pipe wall biofilms in water supply networks under different disinfection strategy pressures and the effect of mediating halogenated acetonitrile formation. CHEMOSPHERE 2023; 344:140382. [PMID: 37806328 DOI: 10.1016/j.chemosphere.2023.140382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 08/23/2023] [Accepted: 10/05/2023] [Indexed: 10/10/2023]
Abstract
Residual chlorine and biofilm coexistence is inevitable in drinking water transmission and distribution networks. Understanding the microbial response and its mediated effects on disinfection byproducts under different categories of residual chlorine stress is essential to ensure water safety. The aim of our study was to determine the response of pipe wall biofilms to residual chlorine pressure in chlorine and chloramine systems and to understand the microbially mediated effects on the formation and migration of haloacetonitriles (HANs), typical nitrogenous disinfection byproducts. According to the experimental results, the biofilm response changes under pressure, with significant differences noted in morphological characteristics, the extracellular polymeric substances (EPS) spatial structure, bacterial diversity, and functional abundance potential. Upon incubation with residual chlorine (1.0 ± 0.2 mg/L), the biofilm biomass per unit area, EPS, community abundance, and diversity increased in the chloramine group, and the percentage of viable bacteria increased, potentially indicating that the chloramine group provides a richer variety of organic matter precursors. Compared with the chloramine group, the chlorination group exhibited increased haloacetonitrile formation potential (HANFP), with Rhodococcus (43.2%) dominating the system, whereas the prediction abundance of metabolic functions was advantageous, especially with regard to amino acid metabolism, carbohydrate metabolism, and the biodegradation and metabolism of foreign chemicals. Under chlorine stress, pipe wall biofilms play a stronger role in mediating HAN production. It is inferred that chlorine may stimulates microbial interactions, and more metabolites (e.g., EPS) consume chlorine to protect microbial survival. EPS dominates in biofilms, in which proteins exhibit greater HANFP than polysaccharides.
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Affiliation(s)
- Songyuan Zheng
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Tao Lin
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China.
| | - Xue Zhang
- Suzhou Water Supply Company, Suzhou, 215002, China
| | - Fuchun Jiang
- Suzhou Water Supply Company, Suzhou, 215002, China
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Dos Santos Ribeiro P, Carvalho NB, Aburjaile F, Sousa T, Veríssimo G, Gomes T, Neves F, Blanco L, Lima JA, de Oliveira D, Jaiswal AK, Brenig B, Soares S, Ramos R, Matiuzzi M, Góes-Neto A, Figueira CP, Costa F, Ristow P, Azevedo V. Environmental Biofilms from an Urban Community in Salvador, Brazil, Shelter Previously Uncharacterized Saprophytic Leptospira. MICROBIAL ECOLOGY 2023; 86:2488-2501. [PMID: 37326636 DOI: 10.1007/s00248-023-02253-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 06/04/2023] [Indexed: 06/17/2023]
Abstract
Biofilms are complex microecosystems with valuable ecological roles that can shelter a variety of microorganisms. Spirochetes from the genus Leptospira have been observed to form biofilms in vitro, in rural environments, and in the kidneys of reservoir rats. The genus Leptospira is composed of pathogenic and non-pathogenic species, and the description of new species is ongoing due to the advent of whole genome sequencing. Leptospires have increasingly been isolated from water and soil samples. To investigate the presence of Leptospira in environmental biofilms, we collected three distinct samples of biofilms formed in an urban setting with poor sanitation: Pau da Lima, in Salvador, Bahia, Brazil. All biofilm samples were negative for the presence of pathogenic leptospires via conventional PCR, but cultures containing saprophytic Leptospira were identified. Whole genomes were generated and analyzed for twenty isolates obtained from these biofilms. For species identification, we used digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analysis. The obtained isolates were classified into seven presumptive species from the saprophytic S1 clade. ANI and dDDH analysis suggest that three of those seven species were new. Classical phenotypic tests confirmed the novel isolated bacteria as saprophytic Leptospira. The isolates presented typical morphology and ultrastructure according to scanning electron microscopy and formed biofilms under in vitro conditions. Our data indicate that a diversity of saprophytic Leptospira species survive in the Brazilian poorly sanitized urban environment, in a biofilm lifestyle. We believe our results contribute to a better understanding of Leptospira biology and ecology, considering biofilms as natural environmental reservoirs for leptospires.
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Affiliation(s)
- Priscyla Dos Santos Ribeiro
- Laboratory of Cellular and Molecular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Laboratory of Bacteriology and Health, Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil
- National Institute of Science and Technology in Interdisciplinary and Transdisciplinary Studies in Ecology and Evolution (INCT IN-TREE), Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil
| | - Natália Barbosa Carvalho
- Laboratory of Bacteriology and Health, Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil
- National Institute of Science and Technology in Interdisciplinary and Transdisciplinary Studies in Ecology and Evolution (INCT IN-TREE), Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil
| | - Flávia Aburjaile
- Department of Preventive Veterinary Medicine, Veterinary School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Thiago Sousa
- Laboratory of Cellular and Molecular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Graciete Veríssimo
- Laboratory of Bacteriology and Health, Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil
| | - Talita Gomes
- Laboratory of Cellular and Molecular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Laboratory of Bacteriology and Health, Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil
- National Institute of Science and Technology in Interdisciplinary and Transdisciplinary Studies in Ecology and Evolution (INCT IN-TREE), Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil
| | - Fábio Neves
- Institute of Collective Health, Federal University of Bahia, Salvador, Bahia, Brazil
| | - Luiza Blanco
- Laboratory of Bacteriology and Health, Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil
| | - João Antonio Lima
- Laboratory of Bacteriology and Health, Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil
| | - Daiana de Oliveira
- Institute of Collective Health, Federal University of Bahia, Salvador, Bahia, Brazil
- Gonçalo Moniz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Salvador, Bahia, Brazil
| | - Arun Kumar Jaiswal
- Laboratory of Cellular and Molecular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Bertram Brenig
- Institute of Veterinary Medicine, Burckhardt Weg, University of Göttingen, Göttingen, Germany
| | - Siomar Soares
- Department of Microbiology, Immunology and Parasitology, Institute of Biological and Natural Sciences, Federal University of Triângulo Mineiro, Uberaba, Minas Gerais, Brazil
| | - Rommel Ramos
- Center of Genomics and Systems Biology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Mateus Matiuzzi
- Federal University of Vale Do São Francisco, Petrolina, Pernambuco, Brazil
| | - Aristóteles Góes-Neto
- Department of Microbiology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Federico Costa
- Institute of Collective Health, Federal University of Bahia, Salvador, Bahia, Brazil
- Gonçalo Moniz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Salvador, Bahia, Brazil
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, USA
- Lancaster Medical School, Lancaster University, Lancaster, LA1 4YW, UK
| | - Paula Ristow
- Laboratory of Bacteriology and Health, Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil.
- National Institute of Science and Technology in Interdisciplinary and Transdisciplinary Studies in Ecology and Evolution (INCT IN-TREE), Institute of Biology, Federal University of Bahia, Salvador, Bahia, Brazil.
- Gonçalo Moniz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Salvador, Bahia, Brazil.
| | - Vasco Azevedo
- Laboratory of Cellular and Molecular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
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Palanisamy V, Bosilevac JM, Barkhouse DA, Velez SE, Chitlapilly Dass S. Shotgun-metagenomics reveals a highly diverse and communal microbial network present in the drains of three beef-processing plants. Front Cell Infect Microbiol 2023; 13:1240138. [PMID: 37743870 PMCID: PMC10515220 DOI: 10.3389/fcimb.2023.1240138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 08/08/2023] [Indexed: 09/26/2023] Open
Abstract
Background Multi-species biofilms pose a problem in various environments, especially food-processing environments. The diversity of microorganisms in these biofilms plays a critical role in their integrity and protection against external biotic and abiotic factors. Compared to single-species biofilms, mixed-species biofilms are more resistant to various stresses, including antimicrobials like sanitizers. Therefore, understanding the microbiome composition and diversity in biofilms and their metabolic potential is a priority when developing intervention techniques to combat foodborne pathogens in food processing environments. Methods This study aimed to describe and compare the microbiome profile of 75 drain biofilm samples obtained from five different locations (Hotscale, Hotbox, Cooler, Processing, & Grind room) of three beef-processing plants (Plant A, B & C) taken over two timepoints 2017-18 (T1) and 2021 (T2) by shotgun sequencing. Results Core microbiome analysis found Pseudomonas, Psychrobacter, and Acinetobacter to be the top three prevalent genera among the plants and locations. Alpha diversity analysis demonstrated a high diversity of microbiome present in all the plants and locations across the time points. Functional analysis showed the high metabolic potential of the microbial community with abundance of genes in metabolism, cell-adhesion, motility, and quorum sensing. Moreover, Quaternary Ammonium Compound (QAC) resistance genes were also observed, this is significant as QAC sanitizers are commonly used in many food processing facilities. Multi-functional genes such as transposases, polymerases, permeases, flagellar proteins, and Mobile Genetic Elements (MGEs) were found suggesting these are dynamic microbial communities that work together to protect themselves against environmental stresses through multiple defense mechanisms. Conclusion This study provides a framework for understanding the collective microbial network spanning a beef processing system. The results can be used to develop intervention strategies to best control these highly communicative microbial networks.
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Affiliation(s)
- Vignesh Palanisamy
- Department of Animal Science, Texas A&M University, College Station, TX, United States
| | - Joseph M. Bosilevac
- U. S. Department of Agriculture, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, Lincoln, NE, United States
| | - Darryll A. Barkhouse
- Molecular Center of Excellence, Invisible Sentinel, bioMerieux Inc., Philadelphia, PA, United States
| | - Sarah E. Velez
- Molecular Center of Excellence, Invisible Sentinel, bioMerieux Inc., Philadelphia, PA, United States
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Barbosa A, Miranda S, Azevedo NF, Cerqueira L, Azevedo AS. Imaging biofilms using fluorescence in situ hybridization: seeing is believing. Front Cell Infect Microbiol 2023; 13:1195803. [PMID: 37284501 PMCID: PMC10239779 DOI: 10.3389/fcimb.2023.1195803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 05/08/2023] [Indexed: 06/08/2023] Open
Abstract
Biofilms are complex structures with an intricate relationship between the resident microorganisms, the extracellular matrix, and the surrounding environment. Interest in biofilms is growing exponentially given its ubiquity in so diverse fields such as healthcare, environmental and industry. Molecular techniques (e.g., next-generation sequencing, RNA-seq) have been used to study biofilm properties. However, these techniques disrupt the spatial structure of biofilms; therefore, they do not allow to observe the location/position of biofilm components (e.g., cells, genes, metabolites), which is particularly relevant to explore and study the interactions and functions of microorganisms. Fluorescence in situ hybridization (FISH) has been arguably the most widely used method for an in situ analysis of spatial distribution of biofilms. In this review, an overview on different FISH variants already applied on biofilm studies (e.g., CLASI-FISH, BONCAT-FISH, HiPR-FISH, seq-FISH) will be explored. In combination with confocal laser scanning microscopy, these variants emerged as a powerful approach to visualize, quantify and locate microorganisms, genes, and metabolites inside biofilms. Finally, we discuss new possible research directions for the development of robust and accurate FISH-based approaches that will allow to dig deeper into the biofilm structure and function.
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Affiliation(s)
- Ana Barbosa
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
| | - Sónia Miranda
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP-Instituto de Patologia e Imunologia Molecular, Universidade do Porto, Porto, Portugal
| | - Nuno F. Azevedo
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
| | - Laura Cerqueira
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
| | - Andreia S. Azevedo
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP-Instituto de Patologia e Imunologia Molecular, Universidade do Porto, Porto, Portugal
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9
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Zheng S, Lin T, Chen H, Zhang X, Jiang F. Characterization of young biofilm morphology, disinfection byproduct formation potential and toxicity of renewed water supply pipelines by phosphorus release from corroded pipes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 884:163813. [PMID: 37121323 DOI: 10.1016/j.scitotenv.2023.163813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/18/2023] [Accepted: 04/24/2023] [Indexed: 05/05/2023]
Abstract
The deterioration of drinking water quality due to corrosion of the water supply network has become inevitable and regular renewal of pipes has become a common means of doing so. Severely corroded pipes release certain nutrients (e.g., elemental phosphorus), however, little has been reported on the effect of old pipes on the young biofilm of new pipe sections and on ensuring water safety in the early stages of the water supply. The aim of our study was to model the effect of key phosphorus nutrients released from corroded old pipes on the morphological characteristics of young biofilms in new pipe sections, mediated disinfection byproducts (DBPs) production and their combined toxicity. Based on the experimental results, phosphorus showed significant differences in the morphological characteristics, spatial structure of extracellular polymers (EPS), functional abundance, disinfection byproduct formation potential (DBPsFP) and toxicity of young biofilms. Under residual chlorine (1.0 ± 0.2 mg/L) incubation, the functional abundance of young biofilm metabolism was dominant, particularly amino acid metabolism and carbohydrate metabolism. There is a dynamic balance between the trophic and shedding effects of phosphorus, where concentration changes affect young biofilm morphology and DBPFP. Relatively moderate phosphorus concentrations resulted in the highest density of PN/PS organic precursors in EPS and a clear advantage of DBPFP; relatively high phosphorus conditions had limited promotion of young biofilm, while membrane structure shedding was more pronounced, increasing young biofilm-mediated DBPs production. Nitrogen-containing disinfection byproducts (N-DBPs) in young biofilms had a clear toxicity advantage, with HANs and HNMs being key to controlling cytotoxicity and genotoxicity, respectively.
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Affiliation(s)
- Songyuan Zheng
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China
| | - Tao Lin
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China.
| | - Han Chen
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China
| | - Xue Zhang
- Suzhou Water Supply Company, Suzhou 215002, China
| | - Fuchun Jiang
- Suzhou Water Supply Company, Suzhou 215002, China
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10
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Alvim CB, Ferrer-Polonio E, Bes-Piá MA, Mendoza-Roca JA, Fernández-Navarro J, Alonso-Molina JL, Amorós-Muñoz I. Effect of polystyrene nanoplastics on the activated sludge process performance and biomass characteristics. A laboratory study with a sequencing batch reactor. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 329:117131. [PMID: 36586326 DOI: 10.1016/j.jenvman.2022.117131] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 12/16/2022] [Accepted: 12/21/2022] [Indexed: 06/17/2023]
Abstract
The fate and presence of nanoplastics in wastewater treatment systems is a topic of increasing interest. Furthermore, challenges related to their quantification and identification have made it difficult to set up experimental conditions and compare results between studies. In this study, the effect of 100 nm polystyrene nanoplastics on activated sludge was evaluated. A concentration of 2 μg/L was used to continuously feed a sequencing batch reactor (SBR-NPs). Under the experimental conditions used in this study, no changes were observed in the process performance of the SBR-NPs compared to the reactor used as a control. Neither nitrification nor organic matter removal efficiency, which was 96% for both SBRs, were affected by the presence of 100 nm polystyrene nanoplastics, which suggests that the tested nanoplastics were not sufficiently toxic to the biomass. Although no significant differences in the relative abundances of predominant phyla between SBR-Control and SBR-NPs were observed, a slight shift in the relative abundance of Patescibacteria (1.5 ± 0.6% and 3.7 ± 0.8% in SBR-Control and SBR-NPs, respectively, at the end of the test) occurred. The higher abundance of this phylum in SBR-NPs compared to SBR-Control may suggest that these bacteria have some sensitivity to the presence of 100 nm polystyrene nanoplastics. Furthermore, even with the absence of nitrification inhibition, it was observed stagnation of the growth of Nitrotoga bacteria in SBR-NPs, which also suggests that the polystyrene nanoplastics could have an inhibitory effect on these cells and an impact on nitrification in the long term.
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Affiliation(s)
- C Bretas Alvim
- Instituto de Seguridad Industrial, Radiofísica y Medioambiental, Universitat Politècnica de València, Camino de Vera, S/n, Valencia 46022, Spain
| | - E Ferrer-Polonio
- Instituto de Seguridad Industrial, Radiofísica y Medioambiental, Universitat Politècnica de València, Camino de Vera, S/n, Valencia 46022, Spain
| | - M A Bes-Piá
- Instituto de Seguridad Industrial, Radiofísica y Medioambiental, Universitat Politècnica de València, Camino de Vera, S/n, Valencia 46022, Spain
| | - J A Mendoza-Roca
- Instituto de Seguridad Industrial, Radiofísica y Medioambiental, Universitat Politècnica de València, Camino de Vera, S/n, Valencia 46022, Spain.
| | - J Fernández-Navarro
- Instituto de Ingeniería del Agua y Medio Ambiente, Universitat Politècnica de València, Valencia, 46022, Spain
| | - J L Alonso-Molina
- Instituto de Ingeniería del Agua y Medio Ambiente, Universitat Politècnica de València, Valencia, 46022, Spain
| | - I Amorós-Muñoz
- Instituto de Ingeniería del Agua y Medio Ambiente, Universitat Politècnica de València, Valencia, 46022, Spain
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11
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Yuan X, Cui K, Chen Y, Xu W, Li P, He Y. Response of microbial community and biological nitrogen removal to the accumulation of nonylphenol in sequencing batch reactor. INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY : IJEST 2023; 20:1-12. [PMID: 36817166 PMCID: PMC9923645 DOI: 10.1007/s13762-023-04825-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 08/23/2022] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
The widespread existence of nonylphenol in the environmental rendered from wastewater discharge has become a growing concern for its endocrine disrupting effects on microorganisms. In this study, the performance of nitrifying and denitrifying microbial community in a sequencing batch reactor (SBR) was investigated under different nonylphenol concentrations. The SBR was shown to be less effective in nitrogen removal at higher concentration of nonylphenol. Proteobacteria, Bacteroidetes, and Actinobacteria were characterized by 454 pyrosequencing as the dominant bacteria, nitrogen removal functional bacteria in these three phyla were inhibited by nonylphenol, and Proteobacteria and Actinobacteria were more sensitive to nonylphenol. With the accumulation of nonylphenol, the population of the most abundant denitrifying bacteria (Thauera spp.) and nitrifying bacteria (Nitrosomonas spp.) significantly reduced. Microbial diversity increased due to nonylphenol perturbation, which is indicated by the changes in microbial alpha diversity. Principal component analysis showed high similarity between microbial community in low and high concentration of nonylphenol, and the core genera involved in nitrogen removal had a low correlation with other genera shown in co-occurrence network. Moreover, linear discriminant analysis effect size analysis revealed intergroup differences in microorganisms. The mechanism of accumulated NP on the diversity and metabolism of the microbial community was examined. This paper established a theoretical foundation for the treatment of NP-containing wastewater and provided hints for further research about NP impact on biological nitrogen removal. Graphical abstract Supplementary Information The online version contains supplementary material available at 10.1007/s13762-023-04825-9.
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Affiliation(s)
- X. Yuan
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 246011 China
| | - K. Cui
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 246011 China
| | - Y. Chen
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 246011 China
| | - W. Xu
- Zhejiang Lab, Hangzhou, 310012 China
| | - P. Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240 China
| | - Y. He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240 China
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12
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Xiao K, Wang K, Yu S, Yuan Y, Qin Y, An Y, Zhao X, Zhou Z. Membrane fouling behavior in membrane bioreactors for nitrogen-deficient wastewater pretreated by ammonium ion exchange. J Memb Sci 2023. [DOI: 10.1016/j.memsci.2022.121087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Godzieba M, Zubrowska-Sudol M, Walczak J, Ciesielski S. Development of microbial communities in biofilm and activated sludge in a hybrid reactor. Sci Rep 2022; 12:12558. [PMID: 35869109 PMCID: PMC9307651 DOI: 10.1038/s41598-022-16570-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 07/12/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractMicroorganisms play a key role in biological wastewater treatment. The form in which biomass develops determines the efficiency and mechanisms of organic compound conversion, due to different conditions in various microbial structures. However, the results of studies comparing the microbial communities in biofilm and activated sludge have often conflicted. Therefore, this study compared the composition and development of the bacterial communities in biofilm and activated sludge in a hybrid reactor, employing 16S rRNA sequencing. Statistical analysis of the sequencing data included the identification of taxa characteristic to the biofilm and activated sludge, alpha and beta diversity analysis, and network analysis. These analyses indicated that the biofilm bacterial community was richer and more diverse than the activated sludge community. The mean numbers of OTU were 1614 in the biofilm and 993 in the activated sludge, and the mean values of the Chao1 (1735 vs. 1105) and Shannon (5.3 vs. 4.3) biodiversity indices were significantly higher for the biofilm. The biofilm was a better environment for development of nitrifiers (e.g., Nitrosomonas, Nitrospira) and phosphorus accumulating organisms (Candidatus Accumulibacter). Bacteria in the biofilm co-occurrence network had more connections (based on Spearman's rank correlation coefficient) with each other, indicating that they interact more than those in the activated sludge.
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14
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Cai Y, Luo YH, Long X, Zaidi AA, Shi Y, Zhou D, Rittmann BE. Wastewater treatment for ships experiencing large temperature changes: the activated sludge/membrane-biofilm reactor. CHEMOSPHERE 2022; 307:135852. [PMID: 35963382 DOI: 10.1016/j.chemosphere.2022.135852] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/22/2022] [Accepted: 07/23/2022] [Indexed: 06/15/2023]
Abstract
A particular challenge to treatment systems for ship wastewater comes from low and variable temperatures. We evaluated the temperature response (35-15 °C) of a novel biological treatment system involving activated sludge followed by a membrane-biofilm reactor: the activated sludge/membrane-biofilm reactor (AS-ABfMemR). In this study, a pilot-scale AS-ABfMemR achieved over 96% chemical oxygen demand (COD) and 94% total nitrogen (TN) removal from a ship wastewater (550-960 mgCOD·L-1 and 52-77 mgTN·L-1) with a continuous operation with a hydraulic retention time of 12 h at 25 °C. The effluent COD and TN concentrations met IMO discharge standards at temperatures as low as 17 °C, which reduced the energy consumption for wastewater heating. The COD and TN removals of the biofilm stage became important (up to 34% and 35%, respectively) at low temperatures, and this compensated for the deterioration in performance of the aerobic sludge. The genus Azospira dominated in the biofilm's denitrification removal for TN at low temperature. In addition, the buildup of trans-membrane pressure was so slow that backwashing was not needed over the 90 days of continuous operation. These conclusions indicate that the pilot-scale AS-ABfMemR technology is an effective way for real ship sewage treatment under temperature variations.
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Affiliation(s)
- Yuhang Cai
- Engineering Lab for Water Pollution Control and Resources Recovery of Jilin Province, School of Environment, Northeast Normal University, Changchun, 130117, China; Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, 85271-5701, USA; College of Power and Energy Engineering, Harbin Engineering University, Harbin, 150001, PR China
| | - Yi-Hao Luo
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, 85271-5701, USA
| | - Xiangxing Long
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ 85287-3005, United States
| | - Asad A Zaidi
- Department of Mechanical Engineering, Faculty of Engineering Sciences and Technology, Hamdard University, Karachi, 74600, Pakistan
| | - Yue Shi
- College of Power and Energy Engineering, Harbin Engineering University, Harbin, 150001, PR China.
| | - Dandan Zhou
- Engineering Lab for Water Pollution Control and Resources Recovery of Jilin Province, School of Environment, Northeast Normal University, Changchun, 130117, China
| | - Bruce E Rittmann
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, 85271-5701, USA
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15
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Zheng P, Li Y, Chi Q, Cheng Y, Jiang X, Chen D, Mu Y, Shen J. Structural characteristics and microbial function of biofilm in membrane-aerated biofilm reactor for the biodegradation of volatile pyridine. JOURNAL OF HAZARDOUS MATERIALS 2022; 437:129370. [PMID: 35728312 DOI: 10.1016/j.jhazmat.2022.129370] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/26/2022] [Accepted: 06/09/2022] [Indexed: 06/15/2023]
Abstract
In order to avoid the serious air pollution caused by the volatilization of high recalcitrant pyridine, membrane-aerated biofilm reactor (MABR) with bubble-free aeration was used in this study, with the structural characteristics and microbial function of biofilm emphasized. The results showed that as high as 0.6 kg·m-3·d-1 pyridine could be completely removed in MABR. High pyridine loading thickened the biofilm, but without obvious detachment observed. The distinct stratification of microbes and extracellular polymeric substances were shaped by elevated pyridine load, enhancing the structural heterogeneity of biofilm. The increased tryptophan-like substances as well as α-helix and β-sheet proportion in proteins stabilized the biofilm structure against high influent loading. Based on the identified intermediates, possible pyridine biodegradation pathways were proposed. Multi-omics analyses revealed that the metabolic pathways with initial hydroxylation and reduction reaction was enhanced at high pyridine loading. The functional genes were mainly associated with Pseudomonas and Delftia, might responsible for pyridine biodegradation. The results shed light on the effective treatment of wastewater containing recalcitrant pollutants such as pyridine via MABR.
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Affiliation(s)
- Peng Zheng
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Yan Li
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| | - Qiang Chi
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Youpeng Cheng
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Xinbai Jiang
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Dan Chen
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Yang Mu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Jinyou Shen
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
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16
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Rehman ZU, Momin AA, Aldehaiman A, Irum T, Grünberg R, Arold ST. The exceptionally efficient quorum quenching enzyme LrsL suppresses Pseudomonas aeruginosa biofilm production. Front Microbiol 2022; 13:977673. [PMID: 36071959 PMCID: PMC9441902 DOI: 10.3389/fmicb.2022.977673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
Quorum quenching (QQ) is the enzymatic degradation of molecules used by bacteria for synchronizing their behavior within communities. QQ has attracted wide attention due to its potential to inhibit biofilm formation and suppress the production of virulence factors. Through its capacity to limit biofouling and infections, QQ has applications in water treatment, aquaculture, and healthcare. Several different QQ enzymes have been described; however, they often lack the high stability and catalytic efficiency required for industrial applications. Previously, we identified genes from genome sequences of Red Sea sediment bacteria encoding potential QQ enzymes. In this study, we report that one of them, named LrsL, is a metallo-β-lactamase superfamily QQ enzyme with outstanding catalytic features. X-ray crystallography shows that LrsL is a zinc-binding dimer. LrsL has an unusually hydrophobic substrate binding pocket that can accommodate a broad range of acyl-homoserine lactones (AHLs) with exceptionally high affinity. In vitro, LrsL achieves the highest catalytic efficiency reported thus far for any QQ enzyme with a Kcat/KM of 3 × 107. LrsL effectively inhibited Pseudomonas aeruginosa biofilm formation without affecting bacterial growth. Furthermore, LrsL suppressed the production of exopolysaccharides required for biofilm production. These features, and its capacity to regain its function after prolonged heat denaturation, identify LrsL as a robust and unusually efficient QQ enzyme for clinical and industrial applications.
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Affiliation(s)
- Zahid Ur Rehman
- Bioscience Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Environmental Science Program, Water Desalination and Reuse Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- *Correspondence: Zahid Ur Rehman, ; Stefan T. Arold,
| | - Afaque A. Momin
- Bioscience Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Computational Biology Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Abdullah Aldehaiman
- Bioscience Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Computational Biology Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Tayyaba Irum
- Services Hospital, Services Institute of Medical Sciences, Lahore, Pakistan
| | - Raik Grünberg
- Bioscience Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Computational Biology Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Stefan T. Arold
- Bioscience Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Computational Biology Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Centre de Biologie Structurale (CBS), INSERM, CNRS, Université de Montpellier, Montpellier, France
- *Correspondence: Zahid Ur Rehman, ; Stefan T. Arold,
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17
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Zhang X, Park H, Park YJ, Lee K, Yu H, Shin JH, Choo KH. Photolytic quorum quenching effects on the microbial communities and functional gene expressions in membrane bioreactors. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 819:152017. [PMID: 34852249 DOI: 10.1016/j.scitotenv.2021.152017] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 11/07/2021] [Accepted: 11/23/2021] [Indexed: 06/13/2023]
Abstract
Photolytic quorum quenching by ultraviolet A (UVA) irradiation is an effective strategy for controlling membrane bioreactor (MBR) biofouling; however, its effects on MBR microbial communities and functional genes have not yet been explored. Here, we report on the effects of the UVA irradiation, which mitigates membrane biofouling, on the microbial community structures, alpha and beta diversities, and functional gene expressions in the MBR mixed liquor and biocake (membrane fouling layer) for the first time. The results show that the microbial communities become less diversified when alternating UVA is applied to the MBRs. The changes in the community structure are highly influenced by spatiotemporal factors, such as microbial habitats (mixed liquor and biocake) and reactor operation time, although UVA irradiation also has some impacts on the community. The relative abundance of the Sphingomonadaceae family, which can decompose the furan ring of autoinducer-2 (AI-2) signal molecules, becomes greater with continuous UVA irradiation. Xanthomonadaceae, which produces biofilm-degrading enzymes, is also more abundant with UVA photolysis than without it. Copies of monooxygenase and hydroxylase enzyme-related genes increase in the MBR with longer UVA exposures (i.e., continuous UVA). These enzymes seem to be inducible by UVA, enhancing the AI-2 inactivation. In conclusion, UVA irradiation alters the microbial community and the metabolism in the MBR, contributing to the membrane biofouling mitigation.
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Affiliation(s)
- Xiaolei Zhang
- Advanced Institute of Water Industry, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; School of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, PR China
| | - Hyeona Park
- School of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Yeong-Jun Park
- Department of Agriculture and Life Sciences, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Kibaek Lee
- Advanced Institute of Water Industry, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; Department of Biotechnology and Bioengineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea
| | - Huarong Yu
- Advanced Institute of Water Industry, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; School of Civil Engineering, Guangzhou University, 230 Wai Huan Xi Road, Guangzhou 510006, PR China
| | - Jae-Ho Shin
- Department of Agriculture and Life Sciences, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Kwang-Ho Choo
- Advanced Institute of Water Industry, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; School of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea.
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18
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Jiang B, Shen Y, Lu X, Du Y, Jin N, Li G, Zhang D, Xing Y. Toxicity assessment and microbial response to soil antibiotic exposure: differences between individual and mixed antibiotics. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:460-473. [PMID: 35166274 DOI: 10.1039/d1em00405k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Increasing amounts of antibiotics are introduced into soils, raising great concerns on their ecotoxicological impacts on the soil environment. This work investigated the individual and joint toxicity of three antibiotics, tetracycline (TC), sulfonamide (SD) and erythromycin (EM) via a whole-cell bioreporter assay. TC, SD and EM in aqueous solution demonstrated cytotoxicity, whilst soil exposure showed genotoxicity, indicating that soil particles possibly affected the bioavailability of antibiotics. Toxicity of soils exposed to TC, SD and EM changed over time, demonstrating cytotoxic effects within 14-d exposure and genotoxic effects after 30 days. Joint toxicity of TC, SD and EM in soils instead showed cytotoxicity, suggesting a synergetic effect. High-throughput sequencing suggested that the soil microbial response to individual antibiotics and their mixtures showed a different pattern. Soil microbial community composition was more sensitive to TC, in which the abundance of Pseudomonas, Pirellula, Subdivision3_genera_incertae_sedis and Gemmata varied significantly. Microbial community functions were significantly shifted by EM amendments, including signal transduction mechanisms, cytoskeleton, cell wall/membrane/envelope biogenesis, transcription, chromatin structure and dynamics, and carbohydrate transport and metabolism. This work contributes to a better understanding of the ecological effects and potential risks of individual and joint antibiotics on the soil environment.
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Affiliation(s)
- Bo Jiang
- School of Energy and Environmental Engineering, University of Science & Technology Beijing, Beijing, 100083, PR China.
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science & Technology Beijing, Beijing, 100083, PR China
- National Environmental and Energy Science and Technology International Cooperation Base, University of Science & Technology Beijing, Beijing, 100083, PR China
- State Key Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing, 100084, PR China
| | - Yaoxin Shen
- School of Energy and Environmental Engineering, University of Science & Technology Beijing, Beijing, 100083, PR China.
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science & Technology Beijing, Beijing, 100083, PR China
- National Environmental and Energy Science and Technology International Cooperation Base, University of Science & Technology Beijing, Beijing, 100083, PR China
| | - Xin Lu
- Petrochina North China Gas Marketing Company, Beijing, 100029, PR China
| | - Yufan Du
- School of Energy and Environmental Engineering, University of Science & Technology Beijing, Beijing, 100083, PR China.
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science & Technology Beijing, Beijing, 100083, PR China
- National Environmental and Energy Science and Technology International Cooperation Base, University of Science & Technology Beijing, Beijing, 100083, PR China
| | - Naifu Jin
- School of Environment, Tsinghua University, Beijing, 100084, PR China
- State Key Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing, 100084, PR China
| | - Guanghe Li
- School of Environment, Tsinghua University, Beijing, 100084, PR China
- State Key Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing, 100084, PR China
| | - Dayi Zhang
- School of Environment, Tsinghua University, Beijing, 100084, PR China
- State Key Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing, 100084, PR China
| | - Yi Xing
- School of Energy and Environmental Engineering, University of Science & Technology Beijing, Beijing, 100083, PR China.
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science & Technology Beijing, Beijing, 100083, PR China
- National Environmental and Energy Science and Technology International Cooperation Base, University of Science & Technology Beijing, Beijing, 100083, PR China
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19
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Yan X, Lin T, Wang X, Zhang S, Zhou K. Effects of pipe materials on the characteristic recognition, disinfection byproduct formation, and toxicity risk of pipe wall biofilms during chlorination in water supply pipelines. WATER RESEARCH 2022; 210:117980. [PMID: 34974347 DOI: 10.1016/j.watres.2021.117980] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
There are growing concerns over the contributions of biofilms to disinfection byproduct (DBP) formation in engineered water systems (EWSs). Three kinds of water supply pipes, ductile iron (DI), cement-lined stainless steel (SS) and polyethylene (PE) pipes, were selected for the experiment conducted in this study. Based on test results, the three pipe biofilms showed relatively obvious differences in growth, morphological characteristics, organic components and bacterial diversity. Secreted extracellular polymeric substance (EPS) accounted for more than 90% of the biofilm and had greater disinfection byproduct formation potential (DBPFP) than the cell phases. DI pipe wall biofilms had the highest DBPFP, which to a certain extent means that denser and richer organic matter can be produced as the precursor of different types of DBPs. UHPLC-Q Exactive was used to identify the types of DBPs generated from the chlorination of histidine (His), alanine (Ala) and tryptophan (Trp) shared by the three pipe materials and their formation pathways. Compared to carbonaceous disinfection by-products (C-DBPs), nitrogenous disinfection by-products (N-DBPs) had a significant advantage in toxicity generation potentials in the biofilms, especially dichloroacetonitrile (DCAN) and trichloronitromethane (TCNM). DCAN and haloacetic acids (HAAs) were the key to cytotoxicity in biofilms, while TCNM was dominant in biofilm genotoxicity.
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Affiliation(s)
- Xiaoshu Yan
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Tao Lin
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China.
| | - Xiaoxiang Wang
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Shisheng Zhang
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Kemei Zhou
- Nanjing Water Group CompanyLimited, Nanjing, 210002, China
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20
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Karaolia P, Vasileiadis S, G Michael S, G Karpouzas D, Fatta-Kassinos D. Shotgun metagenomics assessment of the resistome, mobilome, pathogen dynamics and their ecological control modes in full-scale urban wastewater treatment plants. JOURNAL OF HAZARDOUS MATERIALS 2021; 418:126387. [PMID: 34329002 DOI: 10.1016/j.jhazmat.2021.126387] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 06/01/2021] [Accepted: 06/08/2021] [Indexed: 05/28/2023]
Abstract
The conventional activated sludge (CAS) process has limited capacity to remove pathogenic microorganisms and antibiotic resistance genes (ARGs), compared to membrane bioreactors (MBRs). However, the full extent of pathogenic microbial fraction, resistome (antibiotic and biocide resistance genes, ARGs and BRGs) and mobilome (mobile genetic elements, MGE) of urban wastewater treatment plant (UWTP) influents and effluents remains unknown. Thus, the fate of putative pathogenic bacteria, ARGs and potential co-occurrence patterns with BRGs, MGEs and bacterial-predatory microorganisms was determined in two full-scale UWTPs, a MBR and a CAS system, using shotgun metagenomics. Both UWTPs significantly reduced the BOD5 (99.4-99.9%), COD (97.6-99.4%) and TSS (98.9-99.9%). MBR was more effective in reducing the abundance and diversity of pathogen-containing taxa, with 4 and 30 taxa enriched in MBR and CAS effluents, respectively. MBR treatment favored resistance genes associated with triclosan, whereas CAS effluents contained ARGs associated with antibiotics of clinical importance. Correlations between putative pathogenic bacteria, ARG/BRGs/MGEs and bacterial-predatory microorganisms suggested that: (i) opportunistic pathogens (Clostridia, Nocardia) may acquire ARGs against first-line treatments and (ii) bacteriophages may act as a biogenic mechanism of pathogen removal. These findings reinforce the MBR capacity to retain pathogenic components, hence reducing potential health risks associated with treated wastewater reuse.
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Affiliation(s)
- Popi Karaolia
- Nireas-International Water Research Centre, University of Cyprus, P.O. Box 20537, Nicosia, CY 1678, Cyprus
| | - Sotirios Vasileiadis
- Department of Biochemistry and Biotechnology, Laboratory of Plant and Environmental Biotechnology, University of Thessaly, Viopolis Campus, Larissa, GR 41500, Greece
| | - Stella G Michael
- Nireas-International Water Research Centre, University of Cyprus, P.O. Box 20537, Nicosia, CY 1678, Cyprus; Department of Civil and Environmental Engineering, University of Cyprus, P.O. Box 20537, Nicosia, CY 1678, Cyprus
| | - Dimitrios G Karpouzas
- Department of Biochemistry and Biotechnology, Laboratory of Plant and Environmental Biotechnology, University of Thessaly, Viopolis Campus, Larissa, GR 41500, Greece.
| | - Despo Fatta-Kassinos
- Nireas-International Water Research Centre, University of Cyprus, P.O. Box 20537, Nicosia, CY 1678, Cyprus; Department of Civil and Environmental Engineering, University of Cyprus, P.O. Box 20537, Nicosia, CY 1678, Cyprus.
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21
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Jaffe AL, Thomas AD, He C, Keren R, Valentin-Alvarado LE, Munk P, Bouma-Gregson K, Farag IF, Amano Y, Sachdeva R, West PT, Banfield JF. Patterns of Gene Content and Co-occurrence Constrain the Evolutionary Path toward Animal Association in Candidate Phyla Radiation Bacteria. mBio 2021; 12:e0052121. [PMID: 34253055 PMCID: PMC8406219 DOI: 10.1128/mbio.00521-21] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 06/14/2021] [Indexed: 12/20/2022] Open
Abstract
Candidate Phyla Radiation (CPR) bacteria are small, likely episymbiotic organisms found across Earth's ecosystems. Despite their prevalence, the distribution of CPR lineages across habitats and the genomic signatures of transitions among these habitats remain unclear. Here, we expand the genome inventory for Absconditabacteria (SR1), Gracilibacteria, and Saccharibacteria (TM7), CPR bacteria known to occur in both animal-associated and environmental microbiomes, and investigate variation in gene content with habitat of origin. By overlaying phylogeny with habitat information, we show that bacteria from these three lineages have undergone multiple transitions from environmental habitats into animal microbiomes. Based on co-occurrence analyses of hundreds of metagenomes, we extend the prior suggestion that certain Saccharibacteria have broad bacterial host ranges and constrain possible host relationships for Absconditabacteria and Gracilibacteria. Full-proteome analyses show that animal-associated Saccharibacteria have smaller gene repertoires than their environmental counterparts and are enriched in numerous protein families, including those likely functioning in amino acid metabolism, phage defense, and detoxification of peroxide. In contrast, some freshwater Saccharibacteria encode a putative rhodopsin. For protein families exhibiting the clearest patterns of differential habitat distribution, we compared protein and species phylogenies to estimate the incidence of lateral gene transfer and genomic loss occurring over the species tree. These analyses suggest that habitat transitions were likely not accompanied by large transfer or loss events but rather were associated with continuous proteome remodeling. Thus, we speculate that CPR habitat transitions were driven largely by availability of suitable host taxa and were reinforced by acquisition and loss of some capacities. IMPORTANCE Studying the genetic differences between related microorganisms from different environment types can indicate factors associated with their movement among habitats. This is particularly interesting for bacteria from the Candidate Phyla Radiation because their minimal metabolic capabilities require associations with microbial hosts. We found that shifts of Absconditabacteria, Gracilibacteria, and Saccharibacteria between environmental ecosystems and mammalian mouths/guts probably did not involve major episodes of gene gain and loss; rather, gradual genomic change likely followed habitat migration. The results inform our understanding of how little-known microorganisms establish in the human microbiota where they may ultimately impact health.
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Affiliation(s)
- Alexander L Jaffe
- Department of Plant and Microbial Biology, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
| | - Alex D Thomas
- Department of Environmental Science, Policy, and Management, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
- Rocky Mountain Biological Laboratory, Crested Butte, Colorado, USA
| | - Christine He
- Innovative Genomics Institute, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
| | - Ray Keren
- Department of Civil and Environmental Engineering, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
| | - Luis E Valentin-Alvarado
- Department of Plant and Microbial Biology, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
- Innovative Genomics Institute, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
| | - Patrick Munk
- National Food Institute, Technical University of Denmarkgrid.5170.3, Kongens Lyngby, Denmark
| | - Keith Bouma-Gregson
- Department of Earth and Planetary Science, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
- Department of Integrative Biology, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
| | - Ibrahim F Farag
- School of Marine Science and Policy, University of Delaware, Lewes, Delaware, USA
| | - Yuki Amano
- Nuclear Fuel Cycle Engineering Laboratories, Japan Atomic Energy Agencygrid.20256.33, Ibaraki, Japan
- Horonobe Underground Research Center, Japan Atomic Energy Agencygrid.20256.33, Hokkaido, Japan
| | - Rohan Sachdeva
- Innovative Genomics Institute, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
- Department of Earth and Planetary Science, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
| | - Patrick T West
- Department of Medicine (Hematology & Blood and Marrow Transplantation), Stanford University, Stanford, California, USA
| | - Jillian F Banfield
- Department of Environmental Science, Policy, and Management, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
- Innovative Genomics Institute, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
- Department of Earth and Planetary Science, University of California, Berkeleygrid.47840.3f, Berkeley, California, USA
- Chan Zuckerberg Biohub, San Francisco, California, USA
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22
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Rehman ZU, Vrouwenvelder JS, Saikaly PE. Physicochemical Properties of Extracellular Polymeric Substances Produced by Three Bacterial Isolates From Biofouled Reverse Osmosis Membranes. Front Microbiol 2021; 12:668761. [PMID: 34349735 PMCID: PMC8328090 DOI: 10.3389/fmicb.2021.668761] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 06/07/2021] [Indexed: 11/13/2022] Open
Abstract
This work describes the chemical composition of extracellular polymeric substances (EPS) produced by three bacteria (RO1, RO2, and RO3) isolated from a biofouled reverse osmosis (RO) membrane. We isolated pure cultures of three bacterial strains from a 7-year-old biofouled RO module that was used in a full-scale seawater treatment plant. All the bacterial strains showed similar growth rates, biofilm formation, and produced similar quantities of proteins and polysaccharides. The gel permeation chromatography showed that the EPS produced by all the strains has a high molecular weight; however, the EPS produced by strains RO1 and RO3 showed the highest molecular weight. Fourier Transform Infrared Spectroscopy (FTIR), Proton Nuclear Magnetic Resonance (1H NMR), and Carbon NMR (13C NMR) were used for a detailed characterization of the EPS. These physicochemical analyses allowed us to identify features of EPS that are important for biofilm formation. FTIR analysis indicated the presence of α-1,4 glycosidic linkages (920 cm-1) and amide II (1,550 cm-1) in the EPS, the presence of which has been correlated with the fouling potential of bacteria. The presence of α-glycoside linkages was further confirmed by 13C NMR analysis. The 13C NMR analysis also showed that the EPS produced by these bacteria is chemically similar to foulants obtained from biofouled RO membranes in previous studies. Therefore, our results support the hypothesis that the majority of substances that cause fouling on RO membranes originate from bacteria. Investigation using 1H NMR showed that the EPS contained a high abundance of hydrophobic compounds, and these compounds can lead to flux decline in the membrane processes. Genome sequencing of the isolates showed that they represent novel species of bacteria belonging to the genus Bacillus. Examination of genomes showed that these bacteria carry carbohydrates-active enzymes that play a role in the production of polysaccharides. Further genomic studies allowed us to identify proteins involved in the biosynthesis of EPS and flagella involved in biofilm formation. These analyses provide a glimpse into the physicochemical properties of EPS found on the RO membrane. This knowledge can be useful in the rational design of biofilm control treatments for the RO membrane.
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Affiliation(s)
- Zahid Ur Rehman
- Water Desalination and Reuse Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Johannes S Vrouwenvelder
- Water Desalination and Reuse Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Pascal E Saikaly
- Water Desalination and Reuse Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
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23
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Comparison of bacterial communities and antibiotic resistance genes in oxidation ditches and membrane bioreactors. Sci Rep 2021; 11:8955. [PMID: 33903636 PMCID: PMC8076264 DOI: 10.1038/s41598-021-88335-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 04/08/2021] [Indexed: 12/23/2022] Open
Abstract
Oxidation ditches (ODs) and membrane bioreactors (MBRs) are widely used in wastewater treatment plants (WWTPs) with bacteria and antibiotic resistance genes (ARGs) running through the whole system. In this study, metagenomic sequencing was used to compare the bacterial communities and ARGs in the OD and MBR systems, which received the same influent in a WWTP located in Xinjiang, China. The results showed that the removal efficiency of pollutants by the MBR process was better than that by the OD process. The composition and the relative abundance of bacteria in activated sludge were similar at the phylum and genus levels and were not affected by process type. Multidrug, fluoroquinolones and peptides were the main ARG types for the two processes, with macB being the main ARG subtype, and the relative abundance of ARG subtypes in MBR effluent was much higher than that in the OD effluent. The mobile genetic elements (MGEs) in the activated sludge were mainly transposons (tnpA) and insertion sequences (ISs; IS91). These results provide a theoretical basis for process selection and controlling the spread of ARGs.
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24
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Tarafdar A, Sirohi R, Gaur VK, Kumar S, Sharma P, Varjani S, Pandey HO, Sindhu R, Madhavan A, Rajasekharan R, Sim SJ. Engineering interventions in enzyme production: Lab to industrial scale. BIORESOURCE TECHNOLOGY 2021; 326:124771. [PMID: 33550211 DOI: 10.1016/j.biortech.2021.124771] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 01/19/2021] [Accepted: 01/21/2021] [Indexed: 06/12/2023]
Abstract
Commercial enzyme production has gained popularity due to its extensive applications in traditional and modern industrial sectors. Rigorous research activities are being conducted worldwide to make the enzyme production system more efficient, cost-effective and hence, sustainable. To overcome the lacunae in earlier enzyme production methods, new engineering interventions are being introduced to meet the growing demand for industrial enzymes. This review focuses initially on the current global scenario of the enzyme market followed by a discussion on different bioreactor design approaches. The use of novel membrane based, airlift and reciprocating plate bioreactors along with the emergence of micro-reactors have also been discussed. Further, the review covers different modelling and optimization strategies for the enzyme production process including advanced techniques like neural networks, adaptive neuro-fuzzy inference systems and genetic algorithms. Finally, the required thrust areas in the enzyme production sector have been highlighted with directions for future research.
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Affiliation(s)
- Ayon Tarafdar
- Divison of Livestock Production and Management, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, India
| | - Ranjna Sirohi
- Centre for Energy and Environmental Sustainability, Lucknow 226 029, India; Technology Development Centre, CSIR-National Environmental Engineering Research Institute, Nagpur 440 020, India; Department of Chemical & Biological Engineering, Korea University, Seoul 136713, Republic of Korea
| | - Vivek Kumar Gaur
- Environmental Biotechnology Division, Environmental Toxicology Group, CSIR- Indian Institute of Toxicology Research, Lucknow 226 001, India
| | - Sunil Kumar
- Technology Development Centre, CSIR-National Environmental Engineering Research Institute, Nagpur 440 020, India
| | - Poonam Sharma
- Department of Bioengineering, Integral University, Lucknow 226 029, India
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar 382 010, Gujarat, India
| | - Hari Om Pandey
- Divison of Livestock Production and Management, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, India
| | - Raveendran Sindhu
- Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology Thiruvananthapuram 695 019, India
| | - Aravind Madhavan
- Rajiv Gandhi Centre for Biotechnology, Trivandrum 695 014, India
| | | | - Sang Jun Sim
- Department of Chemical & Biological Engineering, Korea University, Seoul 136713, Republic of Korea.
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25
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Takimoto Y, Hatamoto M, Soga T, Kuratate D, Watari T, Yamaguchi T. Maintaining microbial diversity mitigates membrane fouling of an anoxic/oxic membrane bioreactor under starvation condition. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 759:143474. [PMID: 33213916 DOI: 10.1016/j.scitotenv.2020.143474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/25/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
The aim of this study was to evaluate the contribution of dissolved organic carbon (DOC) and microbial community dynamics to membrane fouling development in membrane bioreactor (MBR). We operated laboratory-scale anoxic/oxic-MBRs under prolonged starvation conditions in different seasons and the dynamics and diversity of the microbial communities were investigated. Although fouled-MBRs showed DOC accumulation in the activated sludge (AS), the fouling-mitigated MBR suggested that dissolved oxygen was consumed and DOC of the sludge supernatant was degraded. 16S rRNA genes analysis of AS in the MBRs revealed that Chitinophagaceae and Candidatus Promineofilum specifically increased in the fouling-mitigated MBR, suggesting that they played important roles in membrane fouling mitigation; high microbial diversity in the reactor also contributed to fouling mitigation. In the fouled reactor, enrichment of Xanthomonadaceae might be related to fouling causing substances formation leading to membrane fouling development; lower microbial diversity also contributed to fouling development in the fouled MBR.
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Affiliation(s)
- Yuya Takimoto
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan
| | - Masashi Hatamoto
- Department of Civil and Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan.
| | - Toru Soga
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan
| | - Daiki Kuratate
- Department of Civil and Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan
| | - Takahiro Watari
- Department of Civil and Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan
| | - Takashi Yamaguchi
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan; Department of Civil and Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan
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26
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Li J, Xu Y, Song Q, Yang J, Xie L, Yu S, Zheng L. Polycyclic aromatic hydrocarbon and n-alkane pollution characteristics and structural and functional perturbations to the microbial community: a case-study of historically petroleum-contaminated soil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:10589-10602. [PMID: 33098556 DOI: 10.1007/s11356-020-11301-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/18/2020] [Indexed: 05/25/2023]
Abstract
Characterization of the typical petroleum pollutants, polycyclic aromatic hydrocarbons (PAHs) and n-alkanes, and indigenous microbial community structure and function in historically contaminated soil at petrol stations is critical. Five soil samples were collected from a petrol station in Beijing, China. The concentrations of 16 PAHs and 31 n-alkanes were measured by gas chromatography-mass spectrometry. The total concentrations of PAHs and n-alkanes ranged from 973 ± 55 to 2667 ± 183 μg/kg and 6.40 ± 0.38 to 8.65 ± 0.59 mg/kg (dry weight), respectively, which increased with depth. According to the observed molecular indices, PAHs and n-alkanes originated mostly from petroleum-related sources. The levels of ΣPAHs and the total toxic benzo[a]pyrene equivalent (ranging from 6.41 to 72.54 μg/kg) might exert adverse biological effects. Shotgun metagenomic sequencing was employed to investigate the indigenous microbial community structure and function. The results revealed that Proteobacteria and Actinobacteria were the most abundant phyla, and Nocardioides and Microbacterium were the important genera. Based on COG and KEGG annotations, the highly abundant functional classes were identified, and these functions were involved in allowing microorganisms to adapt to the pressure from contaminants. Five petroleum hydrocarbon degradation-related genes were annotated, revealing the distribution of degrading microorganisms. This work facilitates the understanding of the composition, source, and potential ecological impacts of residual PAHs and n-alkanes in historically contaminated soil.
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Affiliation(s)
- Jian Li
- State Key Laboratory of Petroleum Pollution Control, Beijing, 102206, China
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Ying Xu
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Quanwei Song
- State Key Laboratory of Petroleum Pollution Control, Beijing, 102206, China
| | - Jie Yang
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Lin Xie
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Shihang Yu
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Lei Zheng
- Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, College of Water Sciences, Beijing Normal University, Beijing, 100875, China.
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27
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Tian L, Wang L. Multi-omics analysis reveals structure and function of biofilm microbial communities in a pre-denitrification biofilter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 757:143908. [PMID: 33316516 DOI: 10.1016/j.scitotenv.2020.143908] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 06/12/2023]
Abstract
The highly complex microbial communities in biofilm play crucial roles in the pollutant removal performance of wastewater treatment plants (WWTPs). In the present study, using multi-omics analysis, we studied microbial structure, key enzymes, functional traits, and key metabolic pathways of pre-denitrification biofilter in an urban WWTP in China. The analysis results of metagenomic and metaproteomic showed that Betaproteobacteria and Flavobacteriia were dominant in biofilms. The integrated metagenomic and metaproteomic data showed that the expression of nitrogen metabolism genes was high, and the high proportion of denitrification module indicating that denitrification was the main nitrogen removal pathway. The most abundant denitrifying bacterial genera were: Dechloromonas, Acidovorax, Bosea, Polaromonas, and Chryseobacterium. And microorganisms with denitrification potential may not be able to denitrify in the actual operation of the filter. The integrated analysis of metaproteomic and metabolomic showed that there was a correlation between biofilm microorganisms and metabolites. Metabolomic analysis indicated that metabolic profiles of biofilms varied with layer height. This study provides the first detailed microbial communities and metabolic profiles in a full-scale pre-denitrification biofilter and clarifies the mechanism of denitrification.
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Affiliation(s)
- Lu Tian
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Lin Wang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China.
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28
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Song T, Li S, Yin Z, Bao M, Lu J, Li Y. Hydrolyzed polyacrylamide-containing wastewater treatment using ozone reactor-upflow anaerobic sludge blanket reactor-aerobic biofilm reactor multistage treatment system. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 269:116111. [PMID: 33290953 DOI: 10.1016/j.envpol.2020.116111] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 11/08/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
Polymer flooding is one of the most important enhanced oil recovery techniques. However, a large amount of hydrolyzed polyacrylamide (HPAM)-containing wastewater is produced in the process of polymer flooding, and this poses a potential threat to the environment. In this study, the treatment of HPAM-containing wastewater was analyzed in an ozonic-anaerobic-aerobic multistage treatment process involving an ozone reactor (OR), an upflow anaerobic sludge blanket reactor (UASBR), and an aerobic biofilm reactor (ABR). At an HPAM concentration of 500 mg L-1 and an ozone dose of 25 g O3/g TOC, the HPAM removal rate reached 85.06%. With fracturing of the carbon chain, high-molecular-weight HPAM was degraded into low-molecular-weight compounds. Microbial communities in bioreactors were investigated via high-throughput sequencing, which revealed that norank_c_Bacteroidetes_vadinHA17, norank_f_Cytophagaceae, and Meiothermus were the dominant bacterial groups, and that Methanobacterium, norank_c_WCHA1-57, and Methanosaeta were the key archaeal genera. To the best of our knowledge, this is the first study in which HPAM-containing wastewater is treated using an ozonic-anaerobic-aerobic multistage treatment system. The ideal degradation performance and the presence of keystone microorganisms confirmed that the multistage treatment process is feasible for treatment of HPAM-containing wastewater.
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Affiliation(s)
- Tianwen Song
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, And Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China; College of Chemistry & Chemical Engineering, Ocean University of China, Qingdao, 266100, China; College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, China
| | - Shanshan Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, And Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China; College of Chemistry & Chemical Engineering, Ocean University of China, Qingdao, 266100, China
| | - Zichao Yin
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, And Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China; College of Chemistry & Chemical Engineering, Ocean University of China, Qingdao, 266100, China
| | - Mutai Bao
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, And Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China; College of Chemistry & Chemical Engineering, Ocean University of China, Qingdao, 266100, China.
| | - Jinren Lu
- College of Chemistry & Chemical Engineering, Ocean University of China, Qingdao, 266100, China
| | - Yang Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, And Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China; China Petrochemical Corporation (Sinopec Group), Beijing, 100728, China
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29
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Li BB, Zhi LL, Peng ZY, Ma XX, Li J. Contrasting distribution of antibiotic resistance genes and microbial communities in suspended activated sludge versus attached biofilms in an integrated fixed film activated sludge (IFAS) system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 742:140481. [PMID: 32629253 DOI: 10.1016/j.scitotenv.2020.140481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/22/2020] [Accepted: 06/22/2020] [Indexed: 06/11/2023]
Abstract
Suspended activated sludge (AS) and carrier-attached biofilms simultaneously exist in an integrated fixed film activated sludge (IFAS) system. However, the differentiation of antibiotic resistance genes (ARGs) and microbial communities in different types of biofilms is rarely reported. In this study, successions of ARGs and microbial communities of AS and two types of suspended carrier-attached biofilms over seasons were investigated in the IFAS system of one municipal wastewater treatment plant. Results showed that substantial differences were found in the distribution pattern of ARGs, bacterial communities, and predicted microbial function between AS and attached biofilms. The relative abundances of all detected ARGs in AS were significantly higher than those in attached biofilms. ARGs with higher relative abundances generally existed in K3 carrier (surface area ≥ 800 m2/m3) attached biofilms than those in K1 carrier (surface area ≥ 450 m2/m3) biofilms. The relative abundances of ARGs were negatively correlated with temperature and biochemical oxygen demand (BOD5) and positively correlated with ammonium nitrogen contents for AS but not for attached biofilms. No significant relationship was found between the extracellular polymeric substance (EPS) content and ARG abundance for all samples. Temperature, BOD5, and ammonium nitrogen contents were closely connected to microbial communities. The Bray-Curtis distance of bacterial communities between two adjacent sampling seasons for AS was larger than those of two attached biofilms. Network analysis indicated that the AS network had more positive links and intense connections than the attached biofilm networks, potentially facilitating the dissemination of ARGs. The differential distribution of ARGs among the three types of samples was significantly correlated with the microbial co-occurrence network topological properties. Bray-Curtis distance and network analysis suggest that microbial community is more robust in attached biofilms than in suspended AS. This work provides a more in-depth understanding of ARGs and microbial community distributions in wastewater biofilms.
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Affiliation(s)
- Bing-Bing Li
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Li-Ling Zhi
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Zhi-Ying Peng
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Xin-Xin Ma
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Ji Li
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Engineering Laboratory for Biomass Energy and Carbon Reduction Technology, School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu College of Water Treatment Technology and Material Collaborative Innovation Center, Suzhou 215009, China.
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Lequette K, Ait-Mouheb N, Wéry N. Hydrodynamic effect on biofouling of milli-labyrinth channel and bacterial communities in drip irrigation systems fed with reclaimed wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 738:139778. [PMID: 32531594 DOI: 10.1016/j.scitotenv.2020.139778] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 05/04/2020] [Accepted: 05/26/2020] [Indexed: 06/11/2023]
Abstract
The clogging of drippers due to the development of biofilms reduces the benefits and is an obstacle to the implementation of drip irrigation technology in a reclaimed water context. The narrow section and labyrinth geometry of the dripper channel results the development of a heterogeneous flow behaviours with the vortex zones which it enhance the fouling mechanisms. The objective of this study was to analyse the influence of the three dripper types, defined by their geometric and hydraulic parameters, fed with reclaimed wastewater, on the biofouling kinetics and the bacterial communities. Using optical coherence tomography, we demonstrated that the inlet of the drippers (mainly the first baffle) and vortex zones are the most sensitive area for biofouling. Drippers with the lowest Reynolds number and average cross-section velocity v (1 l·h-1) were the most sensible to biofouling, even if detachment events seemed more frequent in this dripper type. Therefore, dripper flow path with larger v should be consider to improve the anti-clogging performance. In addition, the dripper type and the geometry of the flow path influenced the structure of the bacterial communities from dripper biofilms. Relative abundancy of filamentous bacteria belonging to Chloroflexi phylum was higher in 1 l·h-1 drippers, which presented a higher level of biofouling. However, further research on the role of this phylum in dripper biofouling is required.
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Affiliation(s)
- Kévin Lequette
- INRAE, University of Montpellier, LBE, 102, Avenue des Etangs, 11100 Narbonne, France; INRAE, University of Montpellier, UMR G-Eau Avenue Jean-François Breton, 34000 Montpellier, France.
| | - Nassim Ait-Mouheb
- INRAE, University of Montpellier, UMR G-Eau Avenue Jean-François Breton, 34000 Montpellier, France
| | - Nathalie Wéry
- INRAE, University of Montpellier, LBE, 102, Avenue des Etangs, 11100 Narbonne, France
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Morón-López J, Nieto-Reyes L, Molina S, Lezcano MÁ. Exploring microcystin-degrading bacteria thriving on recycled membranes during a cyanobacterial bloom. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 736:139672. [PMID: 32502787 DOI: 10.1016/j.scitotenv.2020.139672] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/22/2020] [Accepted: 05/22/2020] [Indexed: 06/11/2023]
Abstract
Microcystins (MC) are highly toxic secondary metabolites produced by cyanobacterial blooms in many freshwater ecosystems used for recreational and drinking water purposes. So far, biological processes remain to be optimized for an efficient cyanotoxin removal, and new approaches are necessary to compete with physical-chemical treatments. In previous studies we provided a new concept of membrane biofilm reactor made of recycled material, in which a single MC-degrading bacterial strain was inoculated. The present study evaluates the capacity of bacterial consortia associated with freshwater cyanobacterial blooms to form biofilms on recycled membranes and remove MC. Three different discarded reverse osmosis (RO) membranes, previously used in desalination plants after treating brackish water (BWd), seawater (SWd) and brackish water but transformed into nanofiltration (BWt-NF), were exposed to a cyanobacterial bloom in San Juan reservoir (central Spain). Results showed that the three recycled membranes developed a bacterial community with MC removal capacity. Little differences in bacterial coverage and MC removal efficiency between membranes were observed after their exposure in the reservoir. High-throughput sequencing of 16S rRNA gene analysis showed similar bacterial community composition at the phylum level but dissimilar at the order level between the three membranes. This suggests possible surface selectivity on the attached bacterial community. The mlr- candidates such as Burkholderiales and Methylophilales were highly abundant in BWt-NF and BWd, respectively, while mlr+ candidates (e.g. Sphingomonadales) were low abundant in all membranes. Analysis of mlrA and mlrB genes used as markers for MC degradation following mlr-pathway confirmed the presence of this pathway in all membranes. These results suggest the co-existence of both genotypes in membrane-attached native biofilms. Therefore, this study confirms that recycled membranes are suitable support for many MC-degrading bacteria, thus giving value to discarded membranes for eco-friendly and low-cost biological filters.
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Affiliation(s)
- Jesús Morón-López
- IMDEA Water Institute, Punto Com. n° 2, 28805 Alcalá de Henares, Madrid, Spain.; Chemical Engineering Department, University of Alcalá, Ctra. Madrid-Barcelona Km 33,600, 28871 Alcalá de Henares, Madrid, Spain..
| | - Lucía Nieto-Reyes
- IMDEA Water Institute, Punto Com. n° 2, 28805 Alcalá de Henares, Madrid, Spain
| | - Serena Molina
- IMDEA Water Institute, Punto Com. n° 2, 28805 Alcalá de Henares, Madrid, Spain..
| | - María Ángeles Lezcano
- Department of Molecular Evolution, Centro de Astrobiología (CSIC-INTA), 28850 Torrejón de Ardoz, Madrid, Spain
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