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Maranha A, Alarico S, Nunes-Costa D, Melo-Marques I, Roxo I, Castanheira P, Caramelo O, Empadinhas N. Drinking Water Microbiota, Entero-Mammary Pathways, and Breast Cancer: Focus on Nontuberculous Mycobacteria. Microorganisms 2024; 12:1425. [PMID: 39065193 PMCID: PMC11279143 DOI: 10.3390/microorganisms12071425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 07/03/2024] [Accepted: 07/09/2024] [Indexed: 07/28/2024] Open
Abstract
The prospect of drinking water serving as a conduit for gut bacteria, artificially selected by disinfection strategies and a lack of monitoring at the point of use, is concerning. Certain opportunistic pathogens, notably some nontuberculous mycobacteria (NTM), often exceed coliform bacteria levels in drinking water, posing safety risks. NTM and other microbiota resist chlorination and thrive in plumbing systems. When inhaled, opportunistic NTM can infect the lungs of immunocompromised or chronically ill patients and the elderly, primarily postmenopausal women. When ingested with drinking water, NTM often survive stomach acidity, reach the intestines, and migrate to other organs using immune cells as vehicles, potentially colonizing tumor tissue, including in breast cancer. The link between the microbiome and cancer is not new, yet the recognition of intratumoral microbiomes is a recent development. Breast cancer risk rises with age, and NTM infections have emerged as a concern among breast cancer patients. In addition to studies hinting at a potential association between chronic NTM infections and lung cancer, NTM have also been detected in breast tumors at levels higher than normal adjacent tissue. Evaluating the risks of continued ingestion of contaminated drinking water is paramount, especially given the ability of various bacteria to migrate from the gut to breast tissue via entero-mammary pathways. This underscores a pressing need to revise water safety monitoring guidelines and delve into hormonal factors, including addressing the disproportionate impact of NTM infections and breast cancer on women and examining the potential health risks posed by the cryptic and unchecked microbiota from drinking water.
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Affiliation(s)
- Ana Maranha
- Center for Neuroscience and Cell Biology (CNC-UC), University of Coimbra, 3004-504 Coimbra, Portugal; (A.M.); (S.A.); (D.N.-C.); (I.M.-M.); (I.R.)
- Centre for Innovative Biomedicine & Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal
| | - Susana Alarico
- Center for Neuroscience and Cell Biology (CNC-UC), University of Coimbra, 3004-504 Coimbra, Portugal; (A.M.); (S.A.); (D.N.-C.); (I.M.-M.); (I.R.)
- Centre for Innovative Biomedicine & Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal
| | - Daniela Nunes-Costa
- Center for Neuroscience and Cell Biology (CNC-UC), University of Coimbra, 3004-504 Coimbra, Portugal; (A.M.); (S.A.); (D.N.-C.); (I.M.-M.); (I.R.)
- Centre for Innovative Biomedicine & Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal
| | - Inês Melo-Marques
- Center for Neuroscience and Cell Biology (CNC-UC), University of Coimbra, 3004-504 Coimbra, Portugal; (A.M.); (S.A.); (D.N.-C.); (I.M.-M.); (I.R.)
- Centre for Innovative Biomedicine & Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal
| | - Inês Roxo
- Center for Neuroscience and Cell Biology (CNC-UC), University of Coimbra, 3004-504 Coimbra, Portugal; (A.M.); (S.A.); (D.N.-C.); (I.M.-M.); (I.R.)
- Centre for Innovative Biomedicine & Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal
- Ph.D. Programme in Biomedicine and Experimental Biology (PDBEB), Institute for Interdisciplinary Research, University of Coimbra, 3004-504 Coimbra, Portugal
| | | | - Olga Caramelo
- Gynecology Department, Coimbra Hospital and University Centre (CHUC), 3004-561 Coimbra, Portugal;
| | - Nuno Empadinhas
- Center for Neuroscience and Cell Biology (CNC-UC), University of Coimbra, 3004-504 Coimbra, Portugal; (A.M.); (S.A.); (D.N.-C.); (I.M.-M.); (I.R.)
- Centre for Innovative Biomedicine & Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal
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LeChevallier MW, Prosser T, Stevens M. Opportunistic Pathogens in Drinking Water Distribution Systems-A Review. Microorganisms 2024; 12:916. [PMID: 38792751 PMCID: PMC11124194 DOI: 10.3390/microorganisms12050916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 04/24/2024] [Accepted: 04/25/2024] [Indexed: 05/26/2024] Open
Abstract
In contrast to "frank" pathogens, like Salmonella entrocolitica, Shigella dysenteriae, and Vibrio cholerae, that always have a probability of disease, "opportunistic" pathogens are organisms that cause an infectious disease in a host with a weakened immune system and rarely in a healthy host. Historically, drinking water treatment has focused on control of frank pathogens, particularly those from human or animal sources (like Giardia lamblia, Cryptosporidium parvum, or Hepatitis A virus), but in recent years outbreaks from drinking water have increasingly been due to opportunistic pathogens. Characteristics of opportunistic pathogens that make them problematic for water treatment include: (1) they are normally present in aquatic environments, (2) they grow in biofilms that protect the bacteria from disinfectants, and (3) under appropriate conditions in drinking water systems (e.g., warm water, stagnation, low disinfectant levels, etc.), these bacteria can amplify to levels that can pose a public health risk. The three most common opportunistic pathogens in drinking water systems are Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa. This report focuses on these organisms to provide information on their public health risk, occurrence in drinking water systems, susceptibility to various disinfectants, and other operational practices (like flushing and cleaning of pipes and storage tanks). In addition, information is provided on a group of nine other opportunistic pathogens that are less commonly found in drinking water systems, including Aeromonas hydrophila, Klebsiella pneumoniae, Serratia marcescens, Burkholderia pseudomallei, Acinetobacter baumannii, Stenotrophomonas maltophilia, Arcobacter butzleri, and several free-living amoebae including Naegleria fowleri and species of Acanthamoeba. The public health risk for these microbes in drinking water is still unclear, but in most cases, efforts to manage Legionella, mycobacteria, and Pseudomonas risks will also be effective for these other opportunistic pathogens. The approach to managing opportunistic pathogens in drinking water supplies focuses on controlling the growth of these organisms. Many of these microbes are normal inhabitants in biofilms in water, so the attention is less on eliminating these organisms from entering the system and more on managing their occurrence and concentrations in the pipe network. With anticipated warming trends associated with climate change, the factors that drive the growth of opportunistic pathogens in drinking water systems will likely increase. It is important, therefore, to evaluate treatment barriers and management activities for control of opportunistic pathogen risks. Controls for primary treatment, particularly for turbidity management and disinfection, should be reviewed to ensure adequacy for opportunistic pathogen control. However, the major focus for the utility's opportunistic pathogen risk reduction plan is the management of biological activity and biofilms in the distribution system. Factors that influence the growth of microbes (primarily in biofilms) in the distribution system include, temperature, disinfectant type and concentration, nutrient levels (measured as AOC or BDOC), stagnation, flushing of pipes and cleaning of storage tank sediments, and corrosion control. Pressure management and distribution system integrity are also important to the microbial quality of water but are related more to the intrusion of contaminants into the distribution system rather than directly related to microbial growth. Summarizing the identified risk from drinking water, the availability and quality of disinfection data for treatment, and guidelines or standards for control showed that adequate information is best available for management of L. pneumophila. For L. pneumophila, the risk for this organism has been clearly established from drinking water, cases have increased worldwide, and it is one of the most identified causes of drinking water outbreaks. Water management best practices (e.g., maintenance of a disinfectant residual throughout the distribution system, flushing and cleaning of sediments in pipelines and storage tanks, among others) have been shown to be effective for control of L. pneumophila in water supplies. In addition, there are well documented management guidelines available for the control of the organism in drinking water distribution systems. By comparison, management of risks for Mycobacteria from water are less clear than for L. pneumophila. Treatment of M. avium is difficult due to its resistance to disinfection, the tendency to form clumps, and attachment to surfaces in biofilms. Additionally, there are no guidelines for management of M. avium in drinking water, and one risk assessment study suggested a low risk of infection. The role of tap water in the transmission of the other opportunistic pathogens is less clear and, in many cases, actions to manage L. pneumophila (e.g., maintenance of a disinfectant residual, flushing, cleaning of storage tanks, etc.) will also be beneficial in helping to manage these organisms as well.
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Affiliation(s)
| | - Toby Prosser
- Melbourne Water, Melbourne, VIC 3001, Australia; (T.P.); (M.S.)
| | - Melita Stevens
- Melbourne Water, Melbourne, VIC 3001, Australia; (T.P.); (M.S.)
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Abkar L, Moghaddam HS, Fowler SJ. Microbial ecology of drinking water from source to tap. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168077. [PMID: 37914126 DOI: 10.1016/j.scitotenv.2023.168077] [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: 07/27/2023] [Revised: 10/20/2023] [Accepted: 10/21/2023] [Indexed: 11/03/2023]
Abstract
As drinking water travels from its source, through various treatment processes, hundreds to thousands of kilometres of distribution network pipes, to the taps in private homes and public buildings, it is exposed to numerous environmental changes, as well as other microbes living in both water and on surfaces. This review aims to identify the key locations and factors that are associated with changes in the drinking water microbiome throughout conventional urban drinking water systems from the source to the tap water. Over the past 15 years, improvements in cultivation-independent methods have enabled studies that allow us to answer such questions. As a result, we are beginning to move towards predicting the impacts of disturbances and interventions resulting ultimately in management of drinking water systems and microbial communities rather than mere observation. Many challenges still exist to achieve effective management, particularly within the premise plumbing environment, which exhibits diverse and inconsistent conditions that may lead to alterations in the microbiota, potentially presenting public health risks. Finally, we recommend the establishment of global collaborative projects on the drinking water microbiome that will enhance our current knowledge and lead to tools for operators and researchers alike to improve global access to high-quality drinking water.
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Affiliation(s)
- Leili Abkar
- Civil Engineering Department, University of British Columbia, Canada.
| | | | - S Jane Fowler
- Department of Biological Sciences, Simon Fraser University, Canada.
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Spencer-Williams I, Meyer M, DePas W, Elliott E, Haig SJ. Assessing the Impacts of Lead Corrosion Control on the Microbial Ecology and Abundance of Drinking-Water-Associated Pathogens in a Full-Scale Drinking Water Distribution System. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:20360-20369. [PMID: 37970641 DOI: 10.1021/acs.est.3c05272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
Increases in phosphate availability in drinking water distribution systems (DWDSs) from the use of phosphate-based corrosion control strategies may result in nutrient and microbial community composition shifts in the DWDS. This study assessed the year-long impacts of full-scale DWDS orthophosphate addition on both the microbial ecology and density of drinking-water-associated pathogens that infect the immunocompromised (DWPIs). Using 16S rRNA gene amplicon sequencing and droplet digital PCR, drinking water microbial community composition and DWPI density were examined. Microbial community composition analysis suggested significant compositional changes after the orthophosphate addition. Significant increases in total bacterial density were observed after orthophosphate addition, likely driven by a 2 log 10 increase in nontuberculous mycobacteria (NTM). Linear effect models confirmed the importance of phosphate addition with phosphorus concentration explaining 17% and 12% of the variance in NTM and L. pneumophila density, respectively. To elucidate the impact of phosphate on NTM aggregation, a comparison of planktonic and aggregate fractions of NTM cultures grown at varying phosphate concentrations was conducted. Aggregation assay results suggested that higher phosphate concentrations cause more disaggregation, and the interaction between phosphate and NTM is species specific. This work reveals new insight into the consequences of orthophosphate application on the DWDS microbiome and highlights the importance of proactively monitoring the DWDS for DWPIs.
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Affiliation(s)
- Isaiah Spencer-Williams
- Department of Civil and Environmental Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Mitchell Meyer
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, United States
| | - William DePas
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, United States
| | - Emily Elliott
- Department of Civil and Environmental Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
- Department of Geology and Environmental Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Sarah-Jane Haig
- Department of Civil and Environmental Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
- Department of Environmental & Occupational Health, School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
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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: 1] [Impact Index Per Article: 1.0] [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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6
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Zhou Q, Bian Z, Yang D, Fu L. Stability of Drinking Water Distribution Systems and Control of Disinfection By-Products. TOXICS 2023; 11:606. [PMID: 37505570 PMCID: PMC10385944 DOI: 10.3390/toxics11070606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/07/2023] [Accepted: 07/10/2023] [Indexed: 07/29/2023]
Abstract
The stability of drinking water distribution systems and the management of disinfection by-products are critical to ensuring public health safety. In this paper, the interrelationships between corrosion products in the network, microbes, and drinking water quality are elucidated. This review also discusses the mechanisms through which corrosive by-products from the piping network influence the decay of disinfectants and the formation of harmful disinfection by-products. Factors such as copper corrosion by-products, CuO, Cu2O, and Cu2+ play a significant role in accelerating disinfectant decay and catalyzing the production of by-products. Biofilms on pipe walls react with residual chlorine, leading to the formation of disinfection by-products (DBPs) that also amplify health risks. Finally, this paper finally highlights the potential of peroxymonosulfate (PMS), an industrial oxidant, as a disinfectant that can reduce DBP formation, while acknowledging the risks associated with its corrosive nature. Overall, the impact of the corrosive by-products of pipe scale and microbial communities on water quality in pipe networks is discussed, and recommendations for removing DBPs are presented.
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Affiliation(s)
- Qingwei Zhou
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Zhengfu Bian
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China
| | - Dejun Yang
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China
| | - Li Fu
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
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A Dual Enrichment Strategy Provides Soil- and Digestate-Competent Nitrous Oxide-Respiring Bacteria for Mitigating Climate Forcing in Agriculture. mBio 2022; 13:e0078822. [PMID: 35638872 PMCID: PMC9239227 DOI: 10.1128/mbio.00788-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Manipulating soil metabolism through heavy inoculation with microbes is feasible if organic wastes can be utilized as the substrate for growth and vector as a fertilizer. This, however, requires organisms active in both digestate and soil (generalists). Here, we present a dual enrichment strategy to enrich and isolate such generalists among N2O-respiring bacteria (NRB) in soil and digestates, to be used as an inoculum for strengthening the N2O-reduction capacity of soils. The enrichment strategy utilizes sequential batch enrichment cultures alternating between sterilized digestate and soil as substrates, with each batch initiated with limited O2 and unlimited N2O. The cultures were monitored for gas kinetics and community composition. As predicted by a Lotka-Volterra competition model, cluster analysis identified generalist operational taxonomic units (OTUs) which became dominant, digestate/soil-specialists which did not, and a majority that were gradually diluted out. We isolated several NRBs circumscribed by generalist OTUs. Their denitrification genes and phenotypes predicted a variable capacity to act as N2O-sinks, while all genomes predicted broad catabolic capacity. The latter contrasts with previous attempts to enrich NRB by anaerobic incubation of unsterilized digestate only, which selected for organisms with a catabolic capacity limited to fermentation products. The two isolates with the most promising characteristics as N2O sinks were aPseudomonas sp. with a full-fledged denitrification-pathway and a Cloacibacterium sp. carrying only N2O reductase (clade II), and soil experiments confirmed their capacity to reduce N2O-emissions from soil. The successful enrichment of NRB with broad catabolic spectra suggests that the concept of dual enrichment should also be applicable for enrichment of generalists with traits other than N2O reduction.
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Hu Z, Yang L, Han J, Liu Z, Zhao Y, Jin Y, Sheng Y, Zhu L, Hu B. Human viruses lurking in the environment activated by excessive use of COVID-19 prevention supplies. ENVIRONMENT INTERNATIONAL 2022; 163:107192. [PMID: 35354102 PMCID: PMC8938188 DOI: 10.1016/j.envint.2022.107192] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 02/24/2022] [Accepted: 03/17/2022] [Indexed: 05/09/2023]
Abstract
Due to extensive COVID-19 prevention measures, millions of tons of chemicals penetrated into natural environment. Alterations of human viruses in the environment, the neglected perceiver of environmental fluctuations, remain obscure. To decipher the interaction between human viruses and COVID-19 related chemicals, environmental samples were collected on March 2020 from surroundings of designated hospitals and receivers of wastewater treatment plant effluent in Wuhan. The virus community and chemical concentration were respectively unveiled in virtue of virome and ultra-high-performance liquid chromatography-tandem mass spectrometry. The complex relationship between virus and chemical was ulteriorly elaborated by random forest model. As an indicator, environmental viruses were corroborated to sensitively reflect the ecological disturbance originated from pandemic prevention supplies. Chemicals especially trihalomethanes restrained the virus community diversity. Confronting this adverse scenario, Human gammaherpesvirus 4 and Orf virus with resistance to trihalomethanes flourished while replication potential of Macacine alphaherpesvirus 1 ascended under glucocorticoids stress. Consequently, human viruses lurking in the environment were actuated by COVID-19 prevention chemicals, which was a constant burden to public health in this ongoing pandemic. Besides, segments of SARS-CoV-2 RNA were detected near designated hospitals, suggesting environment as a missing link in the transmission route. This research innovatively underlined the human health risk of pandemic prevention supplies from the virus - environment interaction, appealing for monitoring of environmental viruses in long term.
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Affiliation(s)
- Zhichao Hu
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Lihua Yang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Jian Han
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Zishu Liu
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Yuxiang Zhao
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Yihao Jin
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Yaqi Sheng
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, 310058 China
| | - Lizhong Zhu
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, 310058 China.
| | - Baolan Hu
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
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Proctor C, Garner E, Hamilton KA, Ashbolt NJ, Caverly LJ, Falkinham JO, Haas CN, Prevost M, Prevots DR, Pruden A, Raskin L, Stout J, Haig SJ. Tenets of a holistic approach to drinking water-associated pathogen research, management, and communication. WATER RESEARCH 2022; 211:117997. [PMID: 34999316 PMCID: PMC8821414 DOI: 10.1016/j.watres.2021.117997] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 12/13/2021] [Accepted: 12/19/2021] [Indexed: 05/10/2023]
Abstract
In recent years, drinking water-associated pathogens that can cause infections in immunocompromised or otherwise susceptible individuals (henceforth referred to as DWPI), sometimes referred to as opportunistic pathogens or opportunistic premise plumbing pathogens, have received considerable attention. DWPI research has largely been conducted by experts focusing on specific microorganisms or within silos of expertise. The resulting mitigation approaches optimized for a single microorganism may have unintended consequences and trade-offs for other DWPI or other interests (e.g., energy costs and conservation). For example, the ecological and epidemiological issues characteristic of Legionella pneumophila diverge from those relevant for Mycobacterium avium and other nontuberculous mycobacteria. Recent advances in understanding DWPI as part of a complex microbial ecosystem inhabiting drinking water systems continues to reveal additional challenges: namely, how can all microorganisms of concern be managed simultaneously? In order to protect public health, we must take a more holistic approach in all aspects of the field, including basic research, monitoring methods, risk-based mitigation techniques, and policy. A holistic approach will (i) target multiple microorganisms simultaneously, (ii) involve experts across several disciplines, and (iii) communicate results across disciplines and more broadly, proactively addressing source water-to-customer system management.
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Affiliation(s)
- Caitlin Proctor
- Department of Agricultural and Biological Engineering, Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, USA
| | - Emily Garner
- Wadsworth Department of Civil & Environmental Engineering, West Virginia University, Morgantown, WV, USA
| | - Kerry A Hamilton
- School of Sustainable Engineering and the Built Environment and The Biodesign Centre for Environmental Health Engineering, Arizona State University, Tempe, AZ, USA
| | - Nicholas J Ashbolt
- Faculty of Science and Engineering, Southern Cross University, Gold Coast. Queensland, Australia
| | - Lindsay J Caverly
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Charles N Haas
- Department of Civil, Architectural & Environmental Engineering, Drexel University, Philadelphia, PA, USA
| | - Michele Prevost
- Department of Civil, Geological and Mining Engineering, Polytechnique Montreal, Montreal, Quebec, Canada
| | - D Rebecca Prevots
- Epidemiology Unit, Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Amy Pruden
- Department of Civil & Environmental Engineering, Virginia Tech, Blacksburg, VA USA
| | - Lutgarde Raskin
- Department of Civil & Environmental Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Janet Stout
- Department of Civil & Environmental Engineering, University of Pittsburgh, and Special Pathogens Laboratory, Pittsburgh, PA, USA
| | - Sarah-Jane Haig
- Department of Civil & Environmental Engineering, and Department of Environmental & Occupational Health, University of Pittsburgh, Pittsburgh, PA, USA.
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10
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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: 26] [Impact Index Per Article: 13.0] [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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Zhang X, Lin T, Jiang F, Zhang X, Wang S, Zhang S. Impact of pipe material and chlorination on the biofilm structure and microbial communities. CHEMOSPHERE 2022; 289:133218. [PMID: 34890609 DOI: 10.1016/j.chemosphere.2021.133218] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/04/2021] [Accepted: 12/06/2021] [Indexed: 06/13/2023]
Abstract
Pipe material and residual chlorine are key factors for the drinking water distribution system, and understanding the biofilm ecosystem is vital for water quality safeguard. The aim of our study was to determine the influence of pipe materials (ductile iron, steel, polyethylene) and chlorination on the biofilm structure and microbial community, as shown by the physicochemical properties, extracellular polymeric substances (EPS) structural characteristics, bacterial community composition, and functional traits. EPS spatial properties were studied based on a semi-quantitative confocal laser scanning microscope (CLSM) description. Regarding the impact of chlorination, residule chlorine (1.0 ± 0.3 mg L-1 free chlorine) could inhibit the bacteria colonization, and initiate a potential response to external disinfectants revealed by the EPS spatial distribution changes and communities variation compared to unchlorinated system. Regarding the impact of pipe material, polyethylene (PE) biofilms displayed lower biomass, loose zoogloea structure, lower proteins and polysaccharides content, and poor microbial diversity in contrast to ductile iron and steel biofilms. Pipe material was the more possible driving factor of the biofilm community composition compared to the chlorination based on principal coordinates analysis (PCoA) and permutational multivariate analysis of variance (PERMANOVA). Actinobacteria was dominant in the PE biofilms (45.57%-83.32%), while Alphaproteobacteria (34.30%-73.22%) and Gammaproteobacteria (6.46%-36.82%) were the major classes in the steel and ductile iron biofilms. The genus Rhodococcus was predominant in the PE biofilms. Rhodococcus, Pseudomonas, and Sphingomonas seemed to have a better growth advantage in the chlorinated system and display a stronger disinfectant resistance. Functional sketch prediction indicated the potential impact of pipe material and chlorination on functional pathway abundnce, possible functional pathways associated with infectious disease included. This study provides insights into the impact of pipe material and chlorination on biofilm structure and microbial community and might help to develop monitoring or maintenance strategies to protect the biosafety of the drinking water.
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Affiliation(s)
- Xinyue Zhang
- 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.
| | - Fuchun Jiang
- Suzhou Water Supply Company Limited, Suzhou, 215002, PR China
| | - Xue Zhang
- Suzhou Water Supply Company Limited, Suzhou, 215002, PR China
| | - Shiyu Wang
- 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
| | - Shisheng Zhang
- 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
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12
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Effect of Particle Concentration and Pipe Materials on the Formation of Biofilms in Drinking Water Distribution Systems. WATER 2022. [DOI: 10.3390/w14020224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Microorganism rebreeding and biofilm shedding enter the water body in the process of a drinking water distribution system (DWDS), which poses a threat to public health. Particles in water can gather pollutants as well as providing favorable growth conditions for bacteria. To date, there are a few studies which focus on the relationship between particles and biofilm formation. Therefore, the microbial diversity of biofilms in the different pipe materials and the effect on particle concentration on biofilm formation were investigated in this study. Experiments were carried out under a simulative DWDS (including iron (DI) and polyvinyl chloride (PVC) pipe). The results showed that the microbial diversity in biofilms followed this order: DI pipe > PVC pipe > DI pipe (upper). Moreover, the microbial biomass of biofilm and the fluorescence intensity of extracellular polymeric substances (EPS, produced by microorganisms) were the largest in the absence of particles. The amount of biofilm bacterial and the fluorescence intensity of EPS both showed first an increasing and then decreasing trend with particle concentration increasing. When particle concentration was relatively low, the absorption of particles and bacteria played a major role, however, with the increasing particle concentration, more stable particle–particle were formed and thus, EPS was easily extracted, resulting in the increase of fluorescence intensity of EPS.
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13
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Ng WJ, Tan CT, Bae S. Effects of monochloramine on culturability, viability and persistence of Pseudomonas putida and tap water mixed bacterial community. Appl Microbiol Biotechnol 2021; 105:3799-3810. [PMID: 33885926 DOI: 10.1007/s00253-021-11251-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 02/18/2021] [Accepted: 03/21/2021] [Indexed: 11/26/2022]
Abstract
Bacterial biofilms are able to persist in drinking water distribution systems (DWDS) even if disinfectants such as monochloramine are used to inhibit bacterial colonization and biofilm formation. While studies have determined the monochloramine concentrations required to inhibit bacterial biofilms, not much is known about how bacterial biofilms develop resistance towards monochloramine. This study covers the development of resistance to monochloramine in both single species and mixed bacterial biofilms. Through culturability tests and flow cytometry, exposing bacterial biofilms to monochloramine disinfection using a sub-lethal concentration (1.5 mg/L Cl2, experimentally determined) was sufficient to cause an increase of the monochloramine's inhibitory concentrations by as much as two times than what is initially required to inhibit biofilm growth. Through persister cultures and 16S rRNA next generation sequencing (NGS) studies, mixed bacterial biofilms experienced to monochloramine exposure resulted in more bacterial genera becoming persistent and resistant towards monochloramine. Through this study, bacterial genera that were persistent towards monochloramine were suggested to share common traits including the ability (1) to readily enter a persister or viable but non-culturable (VBNC) state and (2) to form biofilms primarily comprising proteinaceous extra-polymeric substances (EPS). Both of these traits also suggested that selected bacterial genera tended to be more persistent to monochloramine and produce EPS. This study advances our understanding of bacterial biofilm resistance towards monochloramine and showed the importance of maintaining monochloramine concentrations in DWDS to prevent the development of bacterial resistance towards monochloramine. KEY POINTS: • Monochloramine-resistant biofilm was developed after sub-lethal disinfection. • Mixed-species culture experienced monochloramine showed more persistence to monochloramine. • Ability to enter a persister/VBNC state is a common trait of persistent bacteria genera.
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Affiliation(s)
- Wei Jie Ng
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, #07-03 E1A, Singapore, 117576, Singapore
| | - Ching Thong Tan
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, #07-03 E1A, Singapore, 117576, Singapore
| | - Sungwoo Bae
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, #07-03 E1A, Singapore, 117576, Singapore.
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14
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Lytle DA, Pfaller S, Muhlen C, Struewing I, Triantafyllidou S, White C, Hayes S, King D, Lu J. A comprehensive evaluation of monochloramine disinfection on water quality, Legionella and other important microorganisms in a hospital. WATER RESEARCH 2021; 189:116656. [PMID: 33249307 PMCID: PMC8133025 DOI: 10.1016/j.watres.2020.116656] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/15/2020] [Accepted: 11/16/2020] [Indexed: 05/22/2023]
Abstract
Opportunistic pathogens such as Legionella are of significant public health concern in hospitals. Microbiological and water chemistry parameters in hot water throughout an Ohio hospital were monitored monthly before and after the installation of a monochloramine disinfection system over 16 months. Water samples from fifteen hot water sampling sites as well as the municipal water supply entering the hospital were analyzed using both culture and qPCR assays for specific microbial pathogens including Legionella, Pseudomonas spp., nontuberculous Mycobacteria [NTM], as well as for heterotrophic bacteria. Legionella culture assays decreased from 68% of all sites being positive prior to monochloramine addition to 6% positive after monochloramine addition, and these trends were parallel to qPCR results. Considering all samples, NTMs by culture were significantly reduced from 61% to 14% positivity (p<0.001) after monochloramine treatment. Mycobacterium genus-specific qPCR positivity was reduced from 92% to 65%, but the change was not significant. Heterotrophic bacteria (heterotrophic bacteria plate counts [HPCs]) exhibited large variability which skewed statistical results on a per room basis. However, when all samples were considered, a significant decrease in HPCs was observed after monochloramine addition. Lastly, Pseudomonas aeruginosa and Vermamoeba vermiformis demonstrated large and significant decrease of qPCR signals post-chloramination. General water chemistry parameters including monochloramine residual, nitrate, nitrite, pH, temperature, metals and total trihalomethanes (TTHMs) were also measured. Significant monochloramine residuals were consistently observed at all sampling sites with very little free ammonia present and no water quality indications of nitrification (e.g., pH decrease, elevated nitrite or nitrate). The addition of monochloramine had no obvious impact on metals (lead, copper and iron) and disinfection by-products.
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Affiliation(s)
- Darren A Lytle
- U.S. Environmental Protection Agency, ORD, Center for Environmental Solutions and Emergency Response (CESER), 26 W. Martin Luther King Drive, Cincinnati, OH, 45268, United States.
| | - Stacy Pfaller
- U.S. Environmental Protection Agency, ORD, Center for Environmental Solutions and Emergency Response (CESER), 26 W. Martin Luther King Drive, Cincinnati, OH, 45268, United States
| | - Christy Muhlen
- U.S. Environmental Protection Agency, ORD, Center for Environmental Solutions and Emergency Response (CESER), 26 W. Martin Luther King Drive, Cincinnati, OH, 45268, United States
| | - Ian Struewing
- U.S. Environmental Protection Agency, ORD, Center for Environmental Measurement and Modelling (CEMM), 26 W. Martin Luther King Drive, Cincinnati, OH 45268, United States
| | - Simoni Triantafyllidou
- U.S. Environmental Protection Agency, ORD, Center for Environmental Solutions and Emergency Response (CESER), 26 W. Martin Luther King Drive, Cincinnati, OH, 45268, United States
| | - Colin White
- Ohio Environmental Protection Agency, Emerging Contaminants Section, Division of Drinking and Ground Waters, 50 West Town Street, Suite 700 Columbus, OH 43215, United States
| | - Sam Hayes
- U.S. Environmental Protection Agency, ORD, Center for Environmental Solutions and Emergency Response (CESER), 26 W. Martin Luther King Drive, Cincinnati, OH, 45268, United States
| | - Dawn King
- U.S. Environmental Protection Agency, ORD, Center for Environmental Solutions and Emergency Response (CESER), 26 W. Martin Luther King Drive, Cincinnati, OH, 45268, United States
| | - Jingrang Lu
- U.S. Environmental Protection Agency, ORD, Center for Environmental Measurement and Modelling (CEMM), 26 W. Martin Luther King Drive, Cincinnati, OH 45268, United States
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15
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The role of biofilm in the development and dissemination of ubiquitous pathogens in drinking water distribution systems: an overview of surveillance, outbreaks, and prevention. World J Microbiol Biotechnol 2021; 37:36. [PMID: 33507414 DOI: 10.1007/s11274-021-03008-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 01/19/2021] [Indexed: 12/30/2022]
Abstract
A variety of pathogenic microorganisms can survive in the drinking water distribution systems (DWDS) by forming stable biofilms and, thus, continually disseminating their population through the system's dynamic water bodies. The ingestion of the pathogen-contaminated water could trigger a broad spectrum of illnesses and well-being-related obstacles. These waterborne diseases are a significant concern for babies, pregnant women, and significantly low-immune individuals. This review highlights the recent advances in understanding the microbiological aspects of drinking water quality, biofilm formation and its dynamics, health issues caused by the emerging microbes in biofilm, and approaches for biofilm investigation its prevention and suppression in DWDS.
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16
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Mitra M, Nguyen KMAK, Box TW, Gilpin JS, Hamby SR, Berry TL, Duckett EH. Isolation and characterization of a novel bacterial strain from a Tris-Acetate-Phosphate agar medium plate of the green micro-alga Chlamydomonas reinhardtii that can utilize common environmental pollutants as a carbon source. F1000Res 2020; 9:656. [PMID: 32855811 PMCID: PMC7425125 DOI: 10.12688/f1000research.24680.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/19/2020] [Indexed: 12/28/2022] Open
Abstract
Background:Chlamydomonas reinhardtii, a green micro-alga can be grown at the lab heterotrophically or photo-heterotrophically in Tris-Phosphate-Acetate (TAP) medium which contains acetate as the sole carbon source. When grown in TAP medium,
Chlamydomonas can utilize the exogenous acetate in the medium for gluconeogenesis using the glyoxylate cycle, which is also present in many bacteria and higher plants. A novel bacterial strain, LMJ, was isolated from a contaminated TAP medium plate of
Chlamydomonas. We present our work on the isolation and physiological and biochemical characterizations of LMJ. Methods: Several microbiological tests were conducted to characterize LMJ, including its sensitivity to four antibiotics. We amplified and sequenced partially the 16S rRNA gene of LMJ. We tested if LMJ can utilize cyclic alkanes, aromatic hydrocarbons, poly-hydroxyalkanoates, and fresh and combusted car motor oil as the sole carbon source on Tris-Phosphate (TP) agar medium plates for growth. Results: LMJ is a gram-negative rod, oxidase-positive, mesophilic, non-enteric, pigmented, salt-sensitive bacterium. LMJ can ferment glucose, is starch hydrolysis-negative, and is very sensitive to penicillin and chloramphenicol. Preliminary spectrophotometric analyses indicate LMJ produces pyomelanin. NCBI-BLAST analyses of the partial 16S rRNA gene sequence of LMJ showed that it matched to that of an uncultured bacterium clone LIB091_C05_1243. The nearest genus relative of LMJ is an
Acidovorax sp. strain. LMJ was able to use alkane hydrocarbons, fresh and combusted car motor oil, poly-hydroxybutyrate, phenanthrene, naphthalene, benzoic acid and phenyl acetate as the sole carbon source for growth on TP-agar medium plates. Conclusions: LMJ has 99.14% sequence identity with the
Acidovorax sp. strain A16OP12 whose genome has not been sequenced yet. LMJ’s ability to use chemicals that are common environmental pollutants makes it a promising candidate for further investigation for its use in bioremediation and, provides us with an incentive to sequence its genome.
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Affiliation(s)
- Mautusi Mitra
- Department of Biology, University of West Georgia, Carrollton, Georgia, 30118, USA
| | - Kevin Manoap-Anh-Khoa Nguyen
- Department of Biology, University of West Georgia, Carrollton, Georgia, 30118, USA.,Department of Mechanical Engineering, Kennesaw State University, Marietta, Georgia, 30060, USA
| | - Taylor Wayland Box
- Department of Biology, University of West Georgia, Carrollton, Georgia, 30118, USA
| | - Jesse Scott Gilpin
- Department of Biology, University of West Georgia, Carrollton, Georgia, 30118, USA
| | - Seth Ryan Hamby
- Department of Biology, University of West Georgia, Carrollton, Georgia, 30118, USA
| | - Taylor Lynne Berry
- Carrollton High School, Carrollton, Georgia, 30117, USA.,Department of Chemistry and Biochemistry, University of North Georgia, Dahlonega, Georgia, 30597, USA
| | - Erin Harper Duckett
- Department of Biology, University of West Georgia, Carrollton, Georgia, 30118, USA
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17
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Buse HY, Morris BJ, Gomez-Alvarez V, Szabo JG, Hall JS. Legionella Diversity and Spatiotemporal Variation in The Occurrence of Opportunistic Pathogens within a Large Building Water System. Pathogens 2020; 9:E567. [PMID: 32668779 PMCID: PMC7400177 DOI: 10.3390/pathogens9070567] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/06/2020] [Accepted: 07/07/2020] [Indexed: 01/22/2023] Open
Abstract
Understanding Legionella survival mechanisms within building water systems (BWSs) is challenging due to varying engineering, operational, and water quality characteristics unique to each system. This study aimed to evaluate Legionella, mycobacteria, and free-living amoebae occurrence within a BWS over 18-28 months at six locations differing in plumbing material and potable water age, quality, and usage. A total of 114 bulk water and 57 biofilm samples were analyzed. Legionella culturability fluctuated seasonally with most culture-positive samples being collected during the winter compared to the spring, summer, and fall months. Positive and negative correlations between Legionella and L. pneumophila occurrence and other physiochemical and microbial water quality parameters varied between location and sample types. Whole genome sequencing of 19 presumptive Legionella isolates, from four locations across three time points, identified nine isolates as L. pneumophila serogroup (sg) 1 sequence-type (ST) 1; three as L. pneumophila sg5 ST1950 and ST2037; six as L. feeleii; and one as Ochrobactrum. Results showed the presence of a diverse Legionella population with consistent and sporadic occurrence at four and two locations, respectively. Viewed collectively with similar studies, this information will enable a better understanding of the engineering, operational, and water quality parameters supporting Legionella growth within BWSs.
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Affiliation(s)
- Helen Y. Buse
- Homeland Security and Materials Management Division, Center for Environmental Solutions & Emergency Response (CESER), Office of Research and Development (ORD), US Environmental Protection Agency (USEPA), Cincinnati, OH 45268, USA; (J.G.S.); (J.S.H.)
| | - Brian J. Morris
- Pegasus Technical Services, Inc c/o US EPA, Cincinnati, OH 45268, USA;
| | - Vicente Gomez-Alvarez
- Water Infrastructure Division, Center for Environmental Solutions & Emergency Response (CESER), US Environmental Protection Agency (USEPA), Office of Research and Development (ORD), Cincinnati, OH 45268, USA;
| | - Jeffrey G. Szabo
- Homeland Security and Materials Management Division, Center for Environmental Solutions & Emergency Response (CESER), Office of Research and Development (ORD), US Environmental Protection Agency (USEPA), Cincinnati, OH 45268, USA; (J.G.S.); (J.S.H.)
| | - John S. Hall
- Homeland Security and Materials Management Division, Center for Environmental Solutions & Emergency Response (CESER), Office of Research and Development (ORD), US Environmental Protection Agency (USEPA), Cincinnati, OH 45268, USA; (J.G.S.); (J.S.H.)
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18
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Cruz MC, Woo Y, Flemming HC, Wuertz S. Nitrifying niche differentiation in biofilms from full-scale chloraminated drinking water distribution system. WATER RESEARCH 2020; 176:115738. [PMID: 32259683 DOI: 10.1016/j.watres.2020.115738] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 03/16/2020] [Accepted: 03/17/2020] [Indexed: 06/11/2023]
Abstract
Tropical conditions favour the auto-decomposition of monochloramine (MCA) leading to disinfectant decay and free ammonia in drinking water distribution systems (DWDS); thus, they promote the growth of nitrifiers and the development of biofilms on the inner-pipe surface. Biofilms can adversely impact the provision of safe and biologically stable water. Moreover, there is a general lack of understanding of the role of microbial communities in DWDS in regions with warm temperatures and no distinct seasons. Here, we report a survey on biofilms from full-scale monochloraminated DWDS in a highly urbanised metropolis using next generation sequencing tools. The monitoring campaign consisted of sampling biofilms and bulk waters from 21 in-service pipes. We characterized the microbial community with emphasis on nitrifying bacteria and archaea using 16S rRNA gene amplicon sequencing and potential nitrification activity. Samples grouped into two clusters, characterized by their low (Cluster LD) and high (Cluster HD) α-diversity. Both clusters harbour microorganisms related to nitrification: i) Nitrosomonas (24.9-68.8%), an ammonia oxidising bacterium (AOB) that dominated Cluster LD, and ii) a co-aggregation of genus Nitrospira (9.8-32.5%), a nitrite oxidising bacterium (NOB), and Thaumarchaeota (1.4-10.9%), chemolithotrophic ammonia oxidising (AOA) archaea that were among the most abundant OTUs in Cluster HD. Activity tests performed with fresh biofilm samples confirmed that these two clusters represent distinctive biofilm niches performing different stages of the nitrification process. Cluster LD correlated with a high concentration of MCA, which caused dysbiosis and resulted in high unevenness of the cluster. In cluster HD, with more biomass, chemical reactions involving nitrite increased the MCA demand, releasing ammonia and allowing more nitrifiers to grow, like AOA and NOB. From this study, we conclude that an MCA residual gradient along the DWDS drives and shapes the microbial community assembly and should be considered when designing effective disinfection strategies.
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Affiliation(s)
- Mercedes Cecilia Cruz
- Singapore Centre for Environmental Life Sciences Engineering (SCELSE), 60 Nanyang Drive, Nanyang Technological University, 637551, Singapore
| | - Yissue Woo
- Singapore Centre for Environmental Life Sciences Engineering (SCELSE), 60 Nanyang Drive, Nanyang Technological University, 637551, Singapore
| | - Hans-Curt Flemming
- Singapore Centre for Environmental Life Sciences Engineering (SCELSE), 60 Nanyang Drive, Nanyang Technological University, 637551, Singapore
| | - Stefan Wuertz
- Singapore Centre for Environmental Life Sciences Engineering (SCELSE), 60 Nanyang Drive, Nanyang Technological University, 637551, Singapore; School of Civil and Environmental Engineering, 50 Nanyang Ave, Nanyang Technological University, 639798, Singapore.
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19
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De Sotto R, Tang R, Bae S. Biofilms in premise plumbing systems as a double-edged sword: microbial community composition and functional profiling of biofilms in a tropical region. JOURNAL OF WATER AND HEALTH 2020; 18:172-185. [PMID: 32300090 DOI: 10.2166/wh.2020.182] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To understand distributions of opportunistic premise plumbing pathogens (OPPPs) and microbial community structures governed by sample location, pipe materials, water temperature, age of property and type of house, 29 biofilm samples obtained from faucets, pipes, and shower heads in different households in Singapore were examined using next-generation sequencing technology. Predictive functional profiling of the biofilm communities was also performed to understand the potential of uncultivated microorganisms in premise plumbing systems and their involvement in various metabolic pathways. Microbial community analysis showed Proteobacteria, Bacteroidetes, Acidobacteria, Nitrospira, and Actinobacteria to be the most abundant phyla across the samples which was found to be significantly different when grouped by age of the properties, location, and the type of house. Meanwhile, opportunistic premise plumbing pathogens such as Mycobacterium, Citrobacter, Pseudomonas, Stenotrophomonas, and Methylobacterium were observed from the samples at 0.5% of the total reads. Functional prediction using 16S gene markers revealed the involvement of the biofilm communities in different metabolic pathways like nitrogen metabolism, biodegradation of xenobiotics, and bacterial secretion implying diverse functionalities that are yet to be studied in this environment. This study serves as a preliminary survey on the microbial communities harboring premise plumbing systems in a tropical region like Singapore.
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Affiliation(s)
- Ryan De Sotto
- Department of Civil and Environmental Engineering, National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore E-mail:
| | - Rena Tang
- Department of Civil and Environmental Engineering, National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore E-mail:
| | - Sungwoo Bae
- Department of Civil and Environmental Engineering, National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore E-mail:
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20
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Li W, Tan Q, Zhou W, Chen J, Li Y, Wang F, Zhang J. Impact of substrate material and chlorine/chloramine on the composition and function of a young biofilm microbial community as revealed by high-throughput 16S rRNA sequencing. CHEMOSPHERE 2020; 242:125310. [PMID: 31896192 DOI: 10.1016/j.chemosphere.2019.125310] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 11/02/2019] [Accepted: 11/04/2019] [Indexed: 06/10/2023]
Abstract
The bacterial composition of biofilms in drinking water distribution systems is significantly impacted by the disinfection regime and substrate material. However, studies that have addressed the changes in the biofilm community during the early stage of formation (less than 10 weeks) were not yet adequate. Here, we explore the effects of the substrate materials (cast iron, stainless steel, copper, polyvinyl chloride, and high density polyethylene) and different disinfectants (chlorine and chloramine) on the community composition and function of young biofilm by using 16S rDNA sequencing. The results showed that Alphaproteobacteria (39.14%-80.87%) and Actinobacteria (5.90%-40.03%) were the dominant classes in chlorine-disinfection samples, while Alphaproteobacteria (17.46%-74.18%) and Betaproteobacteria (3.79%-68.50%) became dominant in a chloraminated group. The infrequently discussed genus Phreatobacter became predominant in the chlorinated samples, but it was inhibited by chloramine and copper ions. The key driver of the community composition was indicated as different disinfectants according to principle coordination analysis (PCoA) and Permutational multivariate analysis of variance (Adonis test), and the bacterial community changed significantly over time. Communities of biofilms grown on cast iron showed a great distance from the other materials according to Bray-Curtis dissimilarity, and they had a unique dominant genus, Dechloromonas. A metagenomics prediction based on 16S rDNA was used to detect the functional pathways of antibiotic biosynthesis and beta-lactam resistance, and it revealed that several pathways were significantly different in terms of their chlorinated and chloraminated groups.
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Affiliation(s)
- Weiying Li
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, 200092, China; College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
| | - Qiaowen Tan
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, 200092, China; College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Wei Zhou
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, 200092, China; College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
| | - Jiping Chen
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, 200092, China; College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Yue Li
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, 200092, China; College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Feng Wang
- Institute of Water Environment Technology, MCC Huatian Engineering and Technology Corporation, Nanjing, Jiangsu, 210019, China
| | - Junpeng Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, 200092, China; College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
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21
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Cuellar-Gempeler C, Munguia P. Habitat filters mediate successional trajectories in bacterial communities associated with the striped shore crab. Oecologia 2019; 191:957-970. [PMID: 31690999 DOI: 10.1007/s00442-019-04549-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 10/28/2019] [Indexed: 02/01/2023]
Abstract
The relative importance of stochastic- and niche-based processes shifts during successional time and across different types of habitats. Microbial biofilms are known to undergo such successional shifts. However, little is known about the interaction between these successional trajectories and habitat filters. Harsh habitat filters could affect biofilm successional trajectories by strengthening niche-based processes and weakening stochastic processes. We used mesocosms to track successional trajectories in bacterial communities associated with the striped shore crab (Pachygrapsus transversus). We followed replicated microbial communities under strong and weak habitat filters associated with the crab's gut and carapace. For bacteria, colonization of the crab's gut is constrained by strong chemical and physical filtering, while the carapace remains relatively open for colonization. Consistent with successional models of bacterial biofilms, carapace microbial communities initially converged in community composition at day 8 and diverged thereafter. We expected gut microbial communities to deviate from the trajectory in the carapace and converge towards a subset of tolerant species. Instead, bacterial communities in the gut exhibited low richness, unchanging similarity in composition and turnover in species identities throughout the duration of our study. These habitat filter effects were linked with weak species interactions and low influence from colonization in the gut. If these findings are representative of differences in filter strength in a continuum of successional trajectories, habitat filters may provide basis for predictions that link successional models and habitat types.
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Affiliation(s)
| | - Pablo Munguia
- Royal Melbourne Institute of Technology, Melbourne, Australia
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22
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Aggarwal S, Gomez-Smith CK, Jeon Y, LaPara TM, Waak MB, Hozalski RM. Effects of Chloramine and Coupon Material on Biofilm Abundance and Community Composition in Bench-Scale Simulated Water Distribution Systems and Comparison with Full-Scale Water Mains. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:13077-13088. [PMID: 30351033 DOI: 10.1021/acs.est.8b02607] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The vast majority of bacteria in drinking water distribution systems (DWDSs) reside in biofilms on the interior walls of water mains. Little is known about how water quality conditions affect water-main biofilms because of the inherent limitations in experimenting with drinking water supplies and accessing the water mains for sampling. Bench-scale reactors permit experimentation and ease of biofilm sampling, yet questions remain as to how well biofilms in laboratory reactors represent those on water mains. In this study, the effects of DWDS pipe materials and chloramine residual on biofilms were investigated by cultivating biofilms on cement, polyvinyl chloride, and high density polyethylene coupons in CDC reactors for up to 28 months in the presence of chloraminated or dechlorinated tap water. The bench-scale biofilm microbiomes were then compared with the microbiome on a water main from the full-scale system that supplied the water to the reactors. The presence of a chloramine residual (1.74 ± 0.21 mg/L) suppressed biofilm accumulation and selected for Mycobacterium-like and Sphingopyxis-like operational taxonomic units (OTUs) while the destruction of the chloramine residual resulted in a significant increase in biomass quantity and a shift toward a more diverse community dominated by Nitrospira-like OTUs, which, our results suggest, may be complete ammonia oxidizers (comammox). Coupon material, however, had a relatively minor effect on the abundance and community composition of the biofilm bacteria. Although biofilm communities from the chloraminated water reactor and the water mains shared some dominant populations (namely, Mycobacterium- and Nitrosomonas-like OTUs), the communities were significantly different. This manuscript provides novel insights into the effects of dechlorination and pipe material on biofilm community composition. Furthermore, to our knowledge, it is the first study to compare biofilm in a tap water-fed, bench-scale simulated distribution system to biofilm on water mains from the full-scale system supplying the tap water.
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Affiliation(s)
- Srijan Aggarwal
- Department of Civil and Environmental Engineering , University of Alaska Fairbanks , Fairbanks , Alaska 99775 , United States
| | - C Kimloi Gomez-Smith
- Department of Civil, Environmental, and Geo-Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Youchul Jeon
- Department of Civil and Environmental Engineering , University of Toledo , Toledo , Ohio 43606-339 , United States
| | - Timothy M LaPara
- Department of Civil, Environmental, and Geo-Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
- BioTechnology Institute , University of Minnesota , St. Paul , Minnesota 55108 , United States
| | - Michael B Waak
- Department of Civil and Environmental Engineering , Norwegian University of Science and Technology , 7491 Trondheim , Norway
| | - Raymond M Hozalski
- Department of Civil, Environmental, and Geo-Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
- BioTechnology Institute , University of Minnesota , St. Paul , Minnesota 55108 , United States
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23
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Kettunen S, Lantto U, Koivunen P, Tapiainen T, Uhari M, Renko M. Risk factors for periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome: a case-control study. Eur J Pediatr 2018; 177:1201-1206. [PMID: 29799086 DOI: 10.1007/s00431-018-3175-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 05/04/2018] [Accepted: 05/14/2018] [Indexed: 10/16/2022]
Abstract
UNLABELLED The etiology and pathogenesis of periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome are unclear. We performed a case-control study to evaluate potential environmental or lifestyle factors associated with PFAPA morbidity. We enrolled 119 patients with PFAPA syndrome who had undergone tonsillectomy in Oulu University Hospital between 1987 and 2007. We recruited 230 controls, matched for sex, birth date, and place from the database of the Population Register Center of Finland. All the patients and controls completed a questionnaire regarding exposure to environmental triggers during early childhood. Maternal smoking was more common among PFAPA syndrome patients than controls (23 vs. 14%; P = 0.005). PFAPA patients had lower breastfeeding rates than controls (94 vs. 99%; P = 0.006). No other environmental factors were associated with PFAPA syndrome, except having an aquarium at home (P = 0.007). The patient group also used natural or herbal medicines more often than the controls (P = 0.01). CONCLUSION Maternal smoking and lack of breastfeeding, known risk factors for common childhood infections, were more common in patients with PFAPA syndrome than in matched controls. Environmental factors may be important in the pathogenesis of PFAPA syndrome and should be evaluated in future studies. What is Known: • The pathogenesis and genetics of periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome remain unsolved. • PFAPA syndrome has been shown to cluster in families. What is New: • Maternal smoking and lack of breastfeeding are more common in patients with PFAPA syndrome than in the controls. • Environmental risk factors may be important in the pathogenesis of the syndrome.
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Affiliation(s)
- Sallamaaria Kettunen
- PEDEGO Research Unit, Medical Research Centre, University of Oulu, BOX 5000, FI-90014, Oulu, Finland.,Department of Children and Adolescents, Oulu University Hospital, Oulu, Finland
| | - Ulla Lantto
- PEDEGO Research Unit, Medical Research Centre, University of Oulu, BOX 5000, FI-90014, Oulu, Finland.,Department of Otorhinolaryngology, Oulu University Hospital, Oulu, Finland
| | - Petri Koivunen
- Department of Otorhinolaryngology, Oulu University Hospital, Oulu, Finland
| | - Terhi Tapiainen
- PEDEGO Research Unit, Medical Research Centre, University of Oulu, BOX 5000, FI-90014, Oulu, Finland.,Department of Children and Adolescents, Oulu University Hospital, Oulu, Finland
| | - Matti Uhari
- PEDEGO Research Unit, Medical Research Centre, University of Oulu, BOX 5000, FI-90014, Oulu, Finland.,Department of Children and Adolescents, Oulu University Hospital, Oulu, Finland
| | - Marjo Renko
- PEDEGO Research Unit, Medical Research Centre, University of Oulu, BOX 5000, FI-90014, Oulu, Finland. .,Tampere Centre for Child Health Research, University of Tampere and Tampere University Hospital, Tampere, Finland.
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24
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Lin H, Zhang S, Zhang S, Lin W, Yu X. The function of advanced treatment process in a drinking water treatment plant with organic matter-polluted source water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:8924-8932. [PMID: 26250817 DOI: 10.1007/s11356-015-5116-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Accepted: 07/22/2015] [Indexed: 06/04/2023]
Abstract
To understand the relationship between chemical and microbial treatment at each treatment step, as well as the relationship between microbial community structure in biofilms in biofilters and their ecological functions, a drinking water plant with severe organic matter-polluted source water was investigated. The bacterial community dynamics of two drinking water supply systems (traditional and advanced treatment processes) in this plant were studied from the source to the product water. Analysis by 454 pyrosequencing was conducted to characterize the bacterial diversity in each step of the treatment processes. The bacterial communities in these two treatment processes were highly diverse. Proteobacteria, which mainly consisted of beta-proteobacteria, was the dominant phylum. The two treatment processes used in the plant could effectively remove organic pollutants and microbial polution, especially the advanced treatment process. Significant differences in the detection of the major groups were observed in the product water samples in the treatment processes. The treatment processes, particularly the biological pretreatment and O3-biological activated carbon in the advanced treatment process, highly influenced the microbial community composition and the water quality. Some opportunistic pathogens were found in the water. Nitrogen-relative microorganisms found in the biofilm of filters may perform an important function on the microbial community composition and water quality improvement.
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Affiliation(s)
- Huirong Lin
- Institute of Urban Environment, Chinese Academy of Science, Xiamen, 361021, People's Republic of China
- Ningbo Urban Environment Observation and Research Station-NUEORS, Chinese Academy of Science, Xiamen, People's Republic of China
| | - Shuting Zhang
- Institute of Urban Environment, Chinese Academy of Science, Xiamen, 361021, People's Republic of China
| | - Shenghua Zhang
- Institute of Urban Environment, Chinese Academy of Science, Xiamen, 361021, People's Republic of China
| | - Wenfang Lin
- Institute of Urban Environment, Chinese Academy of Science, Xiamen, 361021, People's Republic of China
| | - Xin Yu
- Institute of Urban Environment, Chinese Academy of Science, Xiamen, 361021, People's Republic of China.
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25
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Zanacic E, McMartin DW, Stavrinides J. From source to filter: changes in bacterial community composition during potable water treatment. Can J Microbiol 2017; 63:546-558. [PMID: 28264165 DOI: 10.1139/cjm-2017-0077] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Rural communities rely on surface water reservoirs for potable water. Effective removal of chemical contaminants and bacterial pathogens from these reservoirs requires an understanding of the bacterial community diversity that is present. In this study, we carried out a 16S rRNA-based profiling approach to describe the bacterial consortia in the raw surface water entering the water treatment plants of 2 rural communities. Our results show that source water is dominated by the Proteobacteria, Bacteroidetes, and Cyanobacteria, with some evidence of seasonal effects altering the predominant groups at each location. A subsequent community analysis of transects of a biological carbon filter in the water treatment plant revealed a significant increase in the proportion of Proteobacteria, Acidobacteria, Planctomycetes, and Nitrospirae relative to raw water. Also, very few enteric coliforms were identified in either the source water or within the filter, although Mycobacterium was of high abundance and was found throughout the filter along with Aeromonas, Legionella, and Pseudomonas. This study provides valuable insight into bacterial community composition within drinking water treatment facilities, and the importance of implementing appropriate disinfection practices to ensure safe potable water for rural communities.
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Affiliation(s)
- Enisa Zanacic
- a Engineering Support & Research, SaskWater, Moose Jaw, Regina, SK S6H 1C8, Canada
| | - Dena W McMartin
- b Faculty of Engineering and Applied Science, University of Regina, Regina, SK S4S 0A2, Canada
| | - John Stavrinides
- c Department of Biology, University of Regina, Regina, SK S4S 0A2, Canada
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26
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Puzon GJ, Wylie JT, Walsh T, Braun K, Morgan MJ. Comparison of biofilm ecology supporting growth of individual Naegleria species in a drinking water distribution system. FEMS Microbiol Ecol 2017; 93:3044201. [DOI: 10.1093/femsec/fix017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 02/20/2017] [Indexed: 01/06/2023] Open
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27
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Mathieu L, Francius G, El Zein R, Angel E, Block JC. Bacterial repopulation of drinking water pipe walls after chlorination. BIOFOULING 2016; 32:925-934. [PMID: 27483985 DOI: 10.1080/08927014.2016.1212989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Accepted: 07/05/2016] [Indexed: 06/06/2023]
Abstract
The short-term kinetics of bacterial repopulation were evaluated after chlorination of high-density polyethylene (HDPE) colonized with drinking water biofilms and compared with bare HDPE surfaces. The effect of chlorination was partial as a residual biofilm persisted and was time-limited as repopulation occurred immediately after water resupply. The total number of bacteria reached the same levels on both the bare and chlorinated biofilm-fouled HDPE after a seven-day exposure to drinking water. Due to the presence of a residual biofilm, the hydrophobicity of chlorinated biofilm-fouled surface exhibited much lower adhesion forces (2.1 nN) compared to bare surfaces (8.9 nN). This could explain the rapid repopulation after chlorination, with a twofold faster bacterial accumulation rate on the bare HDPE surface. γ-Proteobacteria dominated the early stages of repopulation of both surfaces and a shift in the dominance occurred over the colonization time. Such observations define a timescale for cleaning frequency in industrial environments and guidelines for a rinsing procedure using drinking water.
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Affiliation(s)
- Laurence Mathieu
- a EPHE , PSL Research University, Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, LCPME , UMR 7564 , Nancy , France
| | - Grégory Francius
- b CNRS and Université de Lorraine, Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, LCPME , UMR 7564 , Nancy , France
| | - Racha El Zein
- b CNRS and Université de Lorraine, Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, LCPME , UMR 7564 , Nancy , France
| | - Edith Angel
- a EPHE , PSL Research University, Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, LCPME , UMR 7564 , Nancy , France
| | - Jean-Claude Block
- b CNRS and Université de Lorraine, Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, LCPME , UMR 7564 , Nancy , France
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28
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Bédard E, Prévost M, Déziel E. Pseudomonas aeruginosa in premise plumbing of large buildings. Microbiologyopen 2016; 5:937-956. [PMID: 27353357 PMCID: PMC5221438 DOI: 10.1002/mbo3.391] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 06/01/2016] [Accepted: 06/06/2016] [Indexed: 12/27/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic bacterial pathogen that is widely occurring in the environment and is recognized for its capacity to form or join biofilms. The present review consolidates current knowledge on P. aeruginosa ecology and its implication in healthcare facilities premise plumbing. The adaptability of P. aeruginosa and its capacity to integrate the biofilm from the faucet and the drain highlight the role premise plumbing devices can play in promoting growth and persistence. A meta‐analysis of P. aeruginosa prevalence in faucets (manual and electronic) and drains reveals the large variation in device positivity reported and suggest the high variability in the sampling approach and context as the main reason for this variation. The effects of the operating conditions that prevail within water distribution systems (disinfection, temperature, and hydraulic regime) on the persistence of P. aeruginosa are summarized. As a result from the review, recommendations for proactive control measures of water contamination by P. aeruginosa are presented. A better understanding of the ecology of P. aeruginosa and key influencing factors in premise plumbing are essential to identify culprit areas and implement effective control measures.
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Affiliation(s)
- Emilie Bédard
- Department of Civil Engineering, Polytechnique Montréal, Montréal, QC, Canada.,INRS-Institut Armand-Frappier, Laval, QC, Canada
| | - Michèle Prévost
- Department of Civil Engineering, Polytechnique Montréal, Montréal, QC, Canada
| | - Eric Déziel
- INRS-Institut Armand-Frappier, Laval, QC, Canada
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29
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Revetta R, Gomez-Alvarez V, Gerke T, Santo Domingo J, Ashbolt N. Changes in bacterial composition of biofilm in a metropolitan drinking water distribution system. J Appl Microbiol 2016; 121:294-305. [DOI: 10.1111/jam.13150] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 03/15/2016] [Accepted: 03/28/2016] [Indexed: 01/18/2023]
Affiliation(s)
- R.P. Revetta
- United States Environmental Protection Agency; Cincinnati OH USA
| | - V. Gomez-Alvarez
- United States Environmental Protection Agency; Cincinnati OH USA
| | - T.L. Gerke
- ORISE; United States Environmental Protection Agency; Cincinnati OH USA
| | | | - N.J. Ashbolt
- United States Environmental Protection Agency; Cincinnati OH USA
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30
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Biofilms on Hospital Shower Hoses: Characterization and Implications for Nosocomial Infections. Appl Environ Microbiol 2016; 82:2872-2883. [PMID: 26969701 DOI: 10.1128/aem.03529-15] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 02/23/2016] [Indexed: 11/20/2022] Open
Abstract
Although the source of drinking water (DW) used in hospitals is commonly disinfected, biofilms forming on water pipelines are a refuge for bacteria, including possible pathogens that survive different disinfection strategies. These biofilm communities are only beginning to be explored by culture-independent techniques that circumvent the limitations of conventional monitoring efforts. Hence, theories regarding the frequency of opportunistic pathogens in DW biofilms and how biofilm members withstand high doses of disinfectants and/or chlorine residuals in the water supply remain speculative. The aim of this study was to characterize the composition of microbial communities growing on five hospital shower hoses using both 16S rRNA gene sequencing of bacterial isolates and whole-genome shotgun metagenome sequencing. The resulting data revealed a Mycobacterium-like population, closely related to Mycobacterium rhodesiae and Mycobacterium tusciae, to be the predominant taxon in all five samples, and its nearly complete draft genome sequence was recovered. In contrast, the fraction recovered by culture was mostly affiliated with Proteobacteria, including members of the genera Sphingomonas, Blastomonas, and Porphyrobacter.The biofilm community harbored genes related to disinfectant tolerance (2.34% of the total annotated proteins) and a lower abundance of virulence determinants related to colonization and evasion of the host immune system. Additionally, genes potentially conferring resistance to β-lactam, aminoglycoside, amphenicol, and quinolone antibiotics were detected. Collectively, our results underscore the need to understand the microbiome of DW biofilms using metagenomic approaches. This information might lead to more robust management practices that minimize the risks associated with exposure to opportunistic pathogens in hospitals.
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31
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Draft Genome Sequence of Two Sphingopyxis sp. Strains, Dominant Members of the Bacterial Community Associated with a Drinking Water Distribution System Simulator. GENOME ANNOUNCEMENTS 2016; 4:4/2/e00183-16. [PMID: 27034493 PMCID: PMC4816621 DOI: 10.1128/genomea.00183-16] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We report the draft genomes of two Sphingopyxis sp. strains isolated from a chloraminated drinking water distribution system simulator. Both strains are ubiquitous residents and early colonizers of water distribution systems. Genomic annotation identified a class 1 integron (intI1) gene associated with sulfonamide (sul1) and puromycin (pac) antibiotic resistance genes.
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32
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Tejesvi MV, Uhari M, Tapiainen T, Pirttilä AM, Suokas M, Lantto U, Koivunen P, Renko M. Tonsillar microbiota in children with PFAPA (periodic fever, aphthous stomatitis, pharyngitis, and adenitis) syndrome. Eur J Clin Microbiol Infect Dis 2016; 35:963-70. [PMID: 27025724 DOI: 10.1007/s10096-016-2623-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 03/09/2016] [Indexed: 01/12/2023]
Abstract
Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) is a childhood febrile syndrome of unknown origin that is often cured with tonsillectomy. We aimed to compare the bacterial microbiota of the tonsils removed from PFAPA patients with those of controls. We used next-generation sequencing technology to investigate the bacterial microbiota of the tonsils of 30 PFAPA patients and 24 controls. We found significant differences in the presence and relative abundance of many bacteria between PFAPA cases and controls. For example, cyanobacteria, potential producers of microcystins and other toxins, were more common in the case samples (14/30, 47 %) than in the controls (4/24, 17 %, p = 0.02), and the mean relative abundance of cyanobacteria was higher in the case samples (0.2 %) than in the controls (0.01 %, p = 0.01). Streptococci were present in all samples in both groups, but their mean relative abundance was lower in the case samples (3.7 %) than in the controls (9.6 %, p = 0.01). Typical nasopharyngeal microbes such as fusobacteria, Prevotella, Tannerella, Porphyromonas, and Parvimonas dominated the microbiota of the tonsils in both groups. The microbiota of the tonsils removed from PFAPA patients differed significantly from those of the controls. Tonsillar microbiota may play a role in triggering the inflammatory processes that lead to symptoms of PFAPA.
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Affiliation(s)
- M V Tejesvi
- Genetics and Physiology, Faculty of Science, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland
| | - M Uhari
- PEDEGO Research Unit, Medical Research Center Oulu, University of Oulu, P.O. Box 5000, 90014, Oulu, Finland
- Department of Children and Adolescents, Oulu University Hospital, P.O. Box 23, 90029, Oulu, Finland
| | - T Tapiainen
- PEDEGO Research Unit, Medical Research Center Oulu, University of Oulu, P.O. Box 5000, 90014, Oulu, Finland
- Department of Children and Adolescents, Oulu University Hospital, P.O. Box 23, 90029, Oulu, Finland
| | - A M Pirttilä
- Genetics and Physiology, Faculty of Science, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland
| | - M Suokas
- Genetics and Physiology, Faculty of Science, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland
| | - U Lantto
- PEDEGO Research Unit, Medical Research Center Oulu, University of Oulu, P.O. Box 5000, 90014, Oulu, Finland
- Department of Otorhinolaryngology, Oulu University Hospital, P.O. Box 23, 90029, Oulu, Finland
| | - P Koivunen
- PEDEGO Research Unit, Medical Research Center Oulu, University of Oulu, P.O. Box 5000, 90014, Oulu, Finland
- Department of Otorhinolaryngology, Oulu University Hospital, P.O. Box 23, 90029, Oulu, Finland
| | - M Renko
- PEDEGO Research Unit, Medical Research Center Oulu, University of Oulu, P.O. Box 5000, 90014, Oulu, Finland.
- Department of Children and Adolescents, Oulu University Hospital, P.O. Box 23, 90029, Oulu, Finland.
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33
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Shen Y, Huang C, Monroy GL, Janjaroen D, Derlon N, Lin J, Espinosa-Marzal R, Morgenroth E, Boppart SA, Ashbolt NJ, Liu WT, Nguyen TH. Response of Simulated Drinking Water Biofilm Mechanical and Structural Properties to Long-Term Disinfectant Exposure. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:1779-87. [PMID: 26756120 PMCID: PMC5135099 DOI: 10.1021/acs.est.5b04653] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Mechanical and structural properties of biofilms influence the accumulation and release of pathogens in drinking water distribution systems (DWDS). Thus, understanding how long-term residual disinfectants exposure affects biofilm mechanical and structural properties is a necessary aspect for pathogen risk assessment and control. In this study, elastic modulus and structure of groundwater biofilms was monitored by atomic force microscopy (AFM) and optical coherence tomography (OCT) during three months of exposure to monochloramine or free chlorine. After the first month of disinfectant exposure, the mean stiffness of monochloramine- or free-chlorine-treated biofilms was 4 to 9 times higher than those before treatment. Meanwhile, the biofilm thickness decreased from 120 ± 8 μm to 93 ± 6-107 ± 11 μm. The increased surface stiffness and decreased biofilm thickness within the first month of disinfectant exposure was presumably due to the consumption of biomass. However, by the second to third month during disinfectant exposure, the biofilm mean stiffness showed a 2- to 4-fold decrease, and the biofilm thickness increased to 110 ± 7-129 ± 8 μm, suggesting that the biofilms adapted to disinfectant exposure. After three months of the disinfectant exposure process, the disinfected biofilms showed 2-5 times higher mean stiffness (as determined by AFM) and 6-13-fold higher ratios of protein over polysaccharide, as determined by differential staining and confocal laser scanning microscopy (CLSM), than the nondisinfected groundwater biofilms. However, the disinfected biofilms and nondisinfected biofilms showed statistically similar thicknesses (t test, p > 0.05), suggesting that long-term disinfection may not significantly remove net biomass. This study showed how biofilm mechanical and structural properties vary in response to a complex DWDS environment, which will contribute to further research on the risk assessment and control of biofilm-associated-pathogens in DWDS.
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Affiliation(s)
| | | | | | | | - Nicolas Derlon
- Eawag: Swiss Federal Institute of Aquatic Science and Technology , 8600 Dübendorf, Switzerland
| | | | | | - Eberhard Morgenroth
- Eawag: Swiss Federal Institute of Aquatic Science and Technology , 8600 Dübendorf, Switzerland
- Institute of Environmental Engineering, ETH Zürich , 8093 Zürich, Switzerland
| | | | - Nicholas J Ashbolt
- School of Public Health, University of Alberta , Edmonton, AB T6G 2G7 Canada
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34
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Prest EI, Hammes F, van Loosdrecht MCM, Vrouwenvelder JS. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges. Front Microbiol 2016; 7:45. [PMID: 26870010 PMCID: PMC4740787 DOI: 10.3389/fmicb.2016.00045] [Citation(s) in RCA: 193] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 01/11/2016] [Indexed: 12/27/2022] Open
Abstract
Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to maintain good drinking water microbial quality up to consumer's tap. A new definition and methodological approach for biological stability is proposed.
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Affiliation(s)
- Emmanuelle I Prest
- Environmental Biotechnology Group, Department of Biotechnology, Faculty of Applied Sciences, Delft University of Technology Delft, Netherlands
| | - Frederik Hammes
- Department of Environmental Microbiology, Eawag - Swiss Federal Institute of Aquatic Science and Technology Dübendorf, Switzerland
| | - Mark C M van Loosdrecht
- Environmental Biotechnology Group, Department of Biotechnology, Faculty of Applied Sciences, Delft University of Technology Delft, Netherlands
| | - Johannes S Vrouwenvelder
- Environmental Biotechnology Group, Department of Biotechnology, Faculty of Applied Sciences, Delft University of TechnologyDelft, Netherlands; Division of Biological and Environmental Science and Engineering, Water Desalination and Reuse Center, King Abdullah University of Science and TechnologyThuwal, Saudi Arabia; Wetsus - European Centre of Excellence for Sustainable Water TechnologyLeeuwarden, Netherlands
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35
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Whole-Genome Sequences of Four Strains Closely Related to Members of the Mycobacterium chelonae Group, Isolated from Biofilms in a Drinking Water Distribution System Simulator. GENOME ANNOUNCEMENTS 2016; 4:4/1/e01539-15. [PMID: 26798093 PMCID: PMC4722260 DOI: 10.1128/genomea.01539-15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
We report here the draft genome sequences of four Mycobacterium chelonae strains from biofilms subjected to a “chlorine burn” in a chloraminated drinking water distribution system simulator. These opportunistic pathogens have been detected in hospital and municipal water distribution systems, in which biofilms have been recognized as an important factor for their persistence.
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36
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Draft Genome Sequences of Six Mycobacterium immunogenum Strains Obtained from a Chloraminated Drinking Water Distribution System Simulator. GENOME ANNOUNCEMENTS 2016; 4:4/1/e01538-15. [PMID: 26744376 PMCID: PMC4706338 DOI: 10.1128/genomea.01538-15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
We report here the draft genome sequences of six Mycobacterium immunogenum strains isolated from a chloraminated drinking water distribution system simulator subjected to changes in operational parameters. M. immunogenum, a rapidly growing mycobacterium previously reported to be the cause of hypersensitivity pneumonitis from contaminated metalworking fluid aerosols, is becoming a public health concern.
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37
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Saur T, Escudié R, Santa-Catalina G, Bernet N, Milferstedt K. Conservation of acquired morphology and community structure in aged biofilms after facing environmental stress. WATER RESEARCH 2016; 88:164-172. [PMID: 26492343 DOI: 10.1016/j.watres.2015.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 09/28/2015] [Accepted: 10/08/2015] [Indexed: 06/05/2023]
Abstract
The influence of growth history on biofilm morphology and microbial community structure is poorly studied despite its important role for biofilm development. Here, biofilms were exposed to a change in hydrodynamic conditions at different growth stages and we observed how biofilm age affected the change in morphology and bacterial community structure. Biofilms were developed in two bubble column reactors, one operated under constant shear stress and one under variable shear stress. Biofilms were transferred from one reactor to the other at different stages in their development by withdrawing and inserting the support medium from one reactor to the other. The developments of morphology and microbial community structure were followed by image analysis and molecular tools. When transferred early in biofilm development, biofilms adapted to the new hydrodynamic conditions and adopted features of the biofilm already developed in the receiving reactor. Biofilms transferred at a late state of biofilm development continued their initial trajectories of morphology and community development even in a new environment. These biofilms did not immediately adapt to their new environment and kept features acquired during their early growth phase, a property we called memory effect.
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Affiliation(s)
- T Saur
- INRA, UR0050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, F-11100 Narbonne, France
| | - R Escudié
- INRA, UR0050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, F-11100 Narbonne, France
| | - G Santa-Catalina
- INRA, UR0050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, F-11100 Narbonne, France
| | - N Bernet
- INRA, UR0050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, F-11100 Narbonne, France
| | - K Milferstedt
- INRA, UR0050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, F-11100 Narbonne, France.
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38
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Wang X, Xing D, Ren N. p-Nitrophenol degradation and microbial community structure in a biocathode bioelectrochemical system. RSC Adv 2016. [DOI: 10.1039/c6ra17446a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The biocathode bioelectrochemical system (bioc-BES) was used forp-nitrophenol (PNP) degradation with sodium bicarbonate as the carbon source.
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Affiliation(s)
- Xinyu Wang
- State Key Laboratory of Urban Water Resource and Environment
- School of Municipal and Environmental Engineering
- Harbin Institute of Technology
- Harbin 150090
- PR China
| | - Defeng Xing
- State Key Laboratory of Urban Water Resource and Environment
- School of Municipal and Environmental Engineering
- Harbin Institute of Technology
- Harbin 150090
- PR China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment
- School of Municipal and Environmental Engineering
- Harbin Institute of Technology
- Harbin 150090
- PR China
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39
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Mi Z, Dai Y, Xie S, Chen C, Zhang X. Impact of disinfection on drinking water biofilm bacterial community. J Environ Sci (China) 2015; 37:200-205. [PMID: 26574105 DOI: 10.1016/j.jes.2015.04.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 06/05/2023]
Abstract
Disinfectants are commonly applied to control the growth of microorganisms in drinking water distribution systems. However, the effect of disinfection on drinking water microbial community remains poorly understood. The present study investigated the impacts of different disinfectants (chlorine and chloramine) and dosages on biofilm bacterial community in bench-scale pipe section reactors. Illumina MiSeq sequencing illustrated that disinfection strategy could affect both bacterial diversity and community structure of drinking water biofilm. Proteobacteria tended to predominate in chloraminated drinking water biofilms, while Firmicutes in chlorinated and unchlorinated biofilms. The major proteobacterial groups were influenced by both disinfectant type and dosage. In addition, chloramination had a more profound impact on bacterial community than chlorination.
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Affiliation(s)
- Zilong Mi
- State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Tsinghua University, Beijing 100084, China; School of Environment, Tsinghua University, Beijing 100084, China.
| | - Yu Dai
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Shuguang Xie
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
| | - Chao Chen
- State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Tsinghua University, Beijing 100084, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Xiaojian Zhang
- School of Environment, Tsinghua University, Beijing 100084, China.
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40
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Pyrosequencing analysis of bacterial communities in biofilms from different pipe materials in a city drinking water distribution system of East China. Appl Microbiol Biotechnol 2015; 99:10713-24. [DOI: 10.1007/s00253-015-6885-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Accepted: 07/21/2015] [Indexed: 12/19/2022]
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41
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Characterization, Microbial Community Structure, and Pathogen Occurrence in Urban Faucet Biofilms in South China. BIOMED RESEARCH INTERNATIONAL 2015; 2015:401672. [PMID: 26273617 PMCID: PMC4529912 DOI: 10.1155/2015/401672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 12/16/2014] [Accepted: 01/27/2015] [Indexed: 11/20/2022]
Abstract
The composition and microbial community structure of the drinking water system biofilms were investigated using microstructure analysis and 454 pyrosequencing technique in Xiamen city, southeast of China. SEM (scanning electron microscope) results showed different features of biofilm morphology in different fields of PVC pipe. Extracellular matrix material and sparse populations of bacteria (mainly rod-shaped and coccoid) were observed. CLSM (confocal laser scanning microscope) revealed different distributions of attached cells, extracellular proteins, α-polysaccharides, and β-polysaccharides. The biofilms had complex bacterial compositions. Differences in bacteria diversity and composition from different tap materials and ages were observed. Proteobacteria was the common and predominant group in all biofilms samples. Some potential pathogens (Legionellales, Enterobacteriales, Chromatiales, and Pseudomonadales) and corrosive microorganisms were also found in the biofilms. This study provides the information of characterization and visualization of the drinking water biofilms matrix, as well as the microbial community structure and opportunistic pathogens occurrence.
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42
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Falkinham JO, Hilborn ED, Arduino MJ, Pruden A, Edwards MA. Epidemiology and Ecology of Opportunistic Premise Plumbing Pathogens: Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa. ENVIRONMENTAL HEALTH PERSPECTIVES 2015; 123:749-58. [PMID: 25793551 PMCID: PMC4529011 DOI: 10.1289/ehp.1408692] [Citation(s) in RCA: 167] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 03/17/2015] [Indexed: 05/11/2023]
Abstract
BACKGROUND Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa are opportunistic premise plumbing pathogens (OPPPs) that persist and grow in household plumbing, habitats they share with humans. Infections caused by these OPPPs involve individuals with preexisting risk factors and frequently require hospitalization. OBJECTIVES The objectives of this report are to alert professionals of the impact of OPPPs, the fact that 30% of the population may be exposed to OPPPs, and the need to develop means to reduce OPPP exposure. We herein present a review of the epidemiology and ecology of these three bacterial OPPPs, specifically to identify common and unique features. METHODS A Water Research Foundation-sponsored workshop gathered experts from across the United States to review the characteristics of OPPPs, identify problems, and develop a list of research priorities to address critical knowledge gaps with respect to increasing OPPP-associated disease. DISCUSSION OPPPs share the common characteristics of disinfectant resistance and growth in biofilms in water distribution systems or premise plumbing. Thus, they share a number of habitats with humans (e.g., showers) that can lead to exposure and infection. The frequency of OPPP-infected individuals is rising and will likely continue to rise as the number of at-risk individuals is increasing. Improved reporting of OPPP disease and increased understanding of the genetic, physiologic, and structural characteristics governing the persistence and growth of OPPPs in drinking water distribution systems and premise plumbing is needed. CONCLUSIONS Because broadly effective community-level engineering interventions for the control of OPPPs have yet to be identified, and because the number of at-risk individuals will continue to rise, it is likely that OPPP-related infections will continue to increase. However, it is possible that individuals can take measures (e.g., raise hot water heater temperatures and filter water) to reduce home exposures.
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Affiliation(s)
- Joseph O Falkinham
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
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43
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Ashbolt NJ. Environmental (Saprozoic) Pathogens of Engineered Water Systems: Understanding Their Ecology for Risk Assessment and Management. Pathogens 2015; 4:390-405. [PMID: 26102291 PMCID: PMC4493481 DOI: 10.3390/pathogens4020390] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 06/15/2015] [Accepted: 06/15/2015] [Indexed: 11/20/2022] Open
Abstract
Major waterborne (enteric) pathogens are relatively well understood and treatment controls are effective when well managed. However, water-based, saprozoic pathogens that grow within engineered water systems (primarily within biofilms/sediments) cannot be controlled by water treatment alone prior to entry into water distribution and other engineered water systems. Growth within biofilms or as in the case of Legionella pneumophila, primarily within free-living protozoa feeding on biofilms, results from competitive advantage. Meaning, to understand how to manage water-based pathogen diseases (a sub-set of saprozoses) we need to understand the microbial ecology of biofilms; with key factors including biofilm bacterial diversity that influence amoebae hosts and members antagonistic to water-based pathogens, along with impacts from biofilm substratum, water temperature, flow conditions and disinfectant residual—all control variables. Major saprozoic pathogens covering viruses, bacteria, fungi and free-living protozoa are listed, yet today most of the recognized health burden from drinking waters is driven by legionellae, non-tuberculous mycobacteria (NTM) and, to a lesser extent, Pseudomonas aeruginosa. In developing best management practices for engineered water systems based on hazard analysis critical control point (HACCP) or water safety plan (WSP) approaches, multi-factor control strategies, based on quantitative microbial risk assessments need to be developed, to reduce disease from largely opportunistic, water-based pathogens.
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Affiliation(s)
- Nicholas J Ashbolt
- School of Public Health, University of Alberta, Rm 3-57D South Academic Building, Edmonton, AB T6G 2G7, Canada.
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44
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Probst AJ, Weinmaier T, DeSantis TZ, Santo Domingo JW, Ashbolt N. New perspectives on microbial community distortion after whole-genome amplification. PLoS One 2015; 10:e0124158. [PMID: 26010362 PMCID: PMC4444113 DOI: 10.1371/journal.pone.0124158] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 03/02/2015] [Indexed: 11/21/2022] Open
Abstract
Whole-genome amplification (WGA) has become an important tool to explore the genomic information of microorganisms in an environmental sample with limited biomass, however potential selective biases during the amplification processes are poorly understood. Here, we describe the effects of WGA on 31 different microbial communities from five biotopes that also included low-biomass samples from drinking water and groundwater. Our findings provide evidence that microbiome segregation by biotope was possible despite WGA treatment. Nevertheless, samples from different biotopes revealed different levels of distortion, with genomic GC content significantly correlated with WGA perturbation. Certain phylogenetic clades revealed a homogenous trend across various sample types, for instance Alpha- and Betaproteobacteria showed a decrease in their abundance after WGA treatment. On the other hand, Enterobacteriaceae, an important biomarker group for fecal contamination in groundwater and drinking water, were strongly affected by WGA treatment without a predictable pattern. These novel results describe the impact of WGA on low-biomass samples and may highlight issues to be aware of when designing future metagenomic studies that necessitate preceding WGA treatment.
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Affiliation(s)
- Alexander J. Probst
- Department for Bioinformatics, Second Genome Inc., South San Francisco, California, United States of America
| | - Thomas Weinmaier
- Department for Bioinformatics, Second Genome Inc., South San Francisco, California, United States of America
| | - Todd Z. DeSantis
- Department for Bioinformatics, Second Genome Inc., South San Francisco, California, United States of America
| | - Jorge W. Santo Domingo
- U.S. Environmental Protection Agency, Cincinnati, Ohio, United States of America
- * E-mail: (JWS); (NA)
| | - Nicholas Ashbolt
- U.S. Environmental Protection Agency, Cincinnati, Ohio, United States of America
- * E-mail: (JWS); (NA)
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45
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Two Rapidly Growing Mycobacterial Species Isolated from a Brain Abscess: First Whole-Genome Sequences of Mycobacterium immunogenum and Mycobacterium llatzerense. J Clin Microbiol 2015; 53:2374-7. [PMID: 25926490 DOI: 10.1128/jcm.00402-15] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 04/17/2015] [Indexed: 11/20/2022] Open
Abstract
Rapidly growing mycobacteria are rarely found in central nervous system infections. We describe a case of polymicrobial infection in a brain abscess including two rapidly growing Mycobacterium species, M. immunogenum and M. llatzerense. The Mycobacterium isolates were distinguishable by molecular methods, and whole-genome sequencing showed <60% pairwise nucleotide identity.
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46
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Dini-Andreote F, Stegen JC, van Elsas JD, Salles JF. Disentangling mechanisms that mediate the balance between stochastic and deterministic processes in microbial succession. Proc Natl Acad Sci U S A 2015; 112:E1326-32. [PMID: 25733885 PMCID: PMC4371938 DOI: 10.1073/pnas.1414261112] [Citation(s) in RCA: 698] [Impact Index Per Article: 77.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ecological succession and the balance between stochastic and deterministic processes are two major themes within microbial ecology, but these conceptual domains have mostly developed independent of each other. Here we provide a framework that integrates shifts in community assembly processes with microbial primary succession to better understand mechanisms governing the stochastic/deterministic balance. Synthesizing previous work, we devised a conceptual model that links ecosystem development to alternative hypotheses related to shifts in ecological assembly processes. Conceptual model hypotheses were tested by coupling spatiotemporal data on soil bacterial communities with environmental conditions in a salt marsh chronosequence spanning 105 years of succession. Analyses within successional stages showed community composition to be initially governed by stochasticity, but as succession proceeded, there was a progressive increase in deterministic selection correlated with increasing sodium concentration. Analyses of community turnover among successional stages--which provide a larger spatiotemporal scale relative to within stage analyses--revealed that changes in the concentration of soil organic matter were the main predictor of the type and relative influence of determinism. Taken together, these results suggest scale-dependency in the mechanisms underlying selection. To better understand mechanisms governing these patterns, we developed an ecological simulation model that revealed how changes in selective environments cause shifts in the stochastic/deterministic balance. Finally, we propose an extended--and experimentally testable--conceptual model integrating ecological assembly processes with primary and secondary succession. This framework provides a priori hypotheses for future experiments, thereby facilitating a systematic approach to understand assembly and succession in microbial communities across ecosystems.
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Affiliation(s)
- Francisco Dini-Andreote
- Department of Microbial Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands; and
| | - James C Stegen
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352
| | - Jan Dirk van Elsas
- Department of Microbial Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands; and
| | - Joana Falcão Salles
- Department of Microbial Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands; and
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47
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Crouzet M, Le Senechal C, Brözel VS, Costaglioli P, Barthe C, Bonneu M, Garbay B, Vilain S. Exploring early steps in biofilm formation: set-up of an experimental system for molecular studies. BMC Microbiol 2014; 14:253. [PMID: 25266973 PMCID: PMC4189659 DOI: 10.1186/s12866-014-0253-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 09/24/2014] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Bacterial biofilms are predominant in natural ecosystems and constitute a public health threat because of their outstanding resistance to antibacterial treatments and especially to antibiotics. To date, several systems have been developed to grow bacterial biofilms in order to study their phenotypes and the physiology of sessile cells. Although relevant, such systems permit analysis of various aspects of the biofilm state but often after several hours of bacterial growth. RESULTS Here we describe a simple and easy-to-use system for growing P. aeruginosa biofilm based on the medium adsorption onto glass wool fibers. This approach which promotes bacterial contact onto the support, makes it possible to obtain in a few minutes a large population of sessile bacteria. Using this growth system, we demonstrated the feasibility of exploring the early stages of biofilm formation by separating by electrophoresis proteins extracted directly from immobilized cells. Moreover, the involvement of protein synthesis in P. aeruginosa attachment is demonstrated. CONCLUSIONS Our system provides sufficient sessile biomass to perform biochemical and proteomic analyses from the early incubation period, thus paving the way for the molecular analysis of the early stages of colonization that were inaccessible to date.
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Affiliation(s)
- Marc Crouzet
- />University Bordeaux, BPRVS, EA 4135, F-33000 Bordeaux, France
- />Bordeaux INP, BPRVS, EA 4135, F-33000 Bordeaux, France
| | - Caroline Le Senechal
- />University Bordeaux, BPRVS, EA 4135, F-33000 Bordeaux, France
- />Bordeaux INP, BPRVS, EA 4135, F-33000 Bordeaux, France
| | - Volker S Brözel
- />Department of Biology & Microbiology, South Dakota State University, Brookings, SD 57007 USA
- />Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria, 0083 South Africa
| | - Patricia Costaglioli
- />University Bordeaux, BPRVS, EA 4135, F-33000 Bordeaux, France
- />Bordeaux INP, BPRVS, EA 4135, F-33000 Bordeaux, France
- />ENSTBB, 146 rue Léo Saignat, case 87, 33076 Bordeaux cedex, France
| | - Christophe Barthe
- />University Bordeaux, BPRVS, EA 4135, F-33000 Bordeaux, France
- />Bordeaux INP, BPRVS, EA 4135, F-33000 Bordeaux, France
| | - Marc Bonneu
- />University Bordeaux, BPRVS, EA 4135, F-33000 Bordeaux, France
- />Bordeaux INP, BPRVS, EA 4135, F-33000 Bordeaux, France
- />Université de Bordeaux, Centre Génomique Fonctionnelle de Bordeaux, Plateforme Protéome, Bordeaux, F-33000 France
- />ENSTBB, 146 rue Léo Saignat, case 87, 33076 Bordeaux cedex, France
| | - Bertrand Garbay
- />University Bordeaux, BPRVS, EA 4135, F-33000 Bordeaux, France
- />Bordeaux INP, BPRVS, EA 4135, F-33000 Bordeaux, France
- />ENSTBB, 146 rue Léo Saignat, case 87, 33076 Bordeaux cedex, France
| | - Sebastien Vilain
- />University Bordeaux, BPRVS, EA 4135, F-33000 Bordeaux, France
- />Bordeaux INP, BPRVS, EA 4135, F-33000 Bordeaux, France
- />ENSTBB, 146 rue Léo Saignat, case 87, 33076 Bordeaux cedex, France
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48
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Wu H, Zhang J, Mi Z, Xie S, Chen C, Zhang X. Biofilm bacterial communities in urban drinking water distribution systems transporting waters with different purification strategies. Appl Microbiol Biotechnol 2014; 99:1947-55. [DOI: 10.1007/s00253-014-6095-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 08/12/2014] [Accepted: 09/11/2014] [Indexed: 10/24/2022]
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49
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Baron JL, Vikram A, Duda S, Stout JE, Bibby K. Shift in the microbial ecology of a hospital hot water system following the introduction of an on-site monochloramine disinfection system. PLoS One 2014; 9:e102679. [PMID: 25033448 PMCID: PMC4102543 DOI: 10.1371/journal.pone.0102679] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 06/22/2014] [Indexed: 01/14/2023] Open
Abstract
Drinking water distribution systems, including premise plumbing, contain a diverse microbiological community that may include opportunistic pathogens. On-site supplemental disinfection systems have been proposed as a control method for opportunistic pathogens in premise plumbing. The majority of on-site disinfection systems to date have been installed in hospitals due to the high concentration of opportunistic pathogen susceptible occupants. The installation of on-site supplemental disinfection systems in hospitals allows for evaluation of the impact of on-site disinfection systems on drinking water system microbial ecology prior to widespread application. This study evaluated the impact of supplemental monochloramine on the microbial ecology of a hospital's hot water system. Samples were taken three months and immediately prior to monochloramine treatment and monthly for the first six months of treatment, and all samples were subjected to high throughput Illumina 16S rRNA region sequencing. The microbial community composition of monochloramine treated samples was dramatically different than the baseline months. There was an immediate shift towards decreased relative abundance of Betaproteobacteria, and increased relative abundance of Firmicutes, Alphaproteobacteria, Gammaproteobacteria, Cyanobacteria and Actinobacteria. Following treatment, microbial populations grouped by sampling location rather than sampling time. Over the course of treatment the relative abundance of certain genera containing opportunistic pathogens and genera containing denitrifying bacteria increased. The results demonstrate the driving influence of supplemental disinfection on premise plumbing microbial ecology and suggest the value of further investigation into the overall effects of premise plumbing disinfection strategies on microbial ecology and not solely specific target microorganisms.
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Affiliation(s)
- Julianne L. Baron
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Graduate School of Public Health, Pittsburgh, Pennsylvania, United States of America
- Special Pathogens Laboratory, Pittsburgh, Pennsylvania, United States of America
| | - Amit Vikram
- Department of Civil and Environmental Engineering, University of Pittsburgh, Swanson School of Engineering, Pittsburgh, Pennsylvania, United States of America
| | - Scott Duda
- Special Pathogens Laboratory, Pittsburgh, Pennsylvania, United States of America
| | - Janet E. Stout
- Special Pathogens Laboratory, Pittsburgh, Pennsylvania, United States of America
- Department of Civil and Environmental Engineering, University of Pittsburgh, Swanson School of Engineering, Pittsburgh, Pennsylvania, United States of America
| | - Kyle Bibby
- Department of Civil and Environmental Engineering, University of Pittsburgh, Swanson School of Engineering, Pittsburgh, Pennsylvania, United States of America
- Department of Computational and Systems Biology, University of Pittsburgh Medical School, Pittsburgh, Pennsylvania, United States of America
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50
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Gomez-Alvarez V, Schrantz KA, Pressman JG, Wahman DG. Biofilm community dynamics in bench-scale annular reactors simulating arrestment of chloraminated drinking water nitrification. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:5448-5457. [PMID: 24754322 DOI: 10.1021/es5005208] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Annular reactors (ARs) were used to study biofilm community succession and provide ecological insight during nitrification arrestment through simultaneously increasing monochloramine (NH2Cl) and chlorine to nitrogen mass ratios, resulting in four operational periods (I-IV). Analysis of 16S rRNA-encoding gene sequence reads (454-pyrosequencing) examined viable and total biofilm communities and found total samples were representative of the underlying viable community. Bacterial community structure showed dynamic changes corresponding with AR operational parameters. Period I (complete nitrification and no NH2Cl residual) was dominated by Bradyrhizobium (total cumulative distribution: 38%), while environmental Legionella-like phylotypes peaked (19%) during Period II (complete nitrification and minimal NH2Cl residual). Nitrospira moscoviensis (nitrite-oxidizing bacteria) was detected in early periods (2%) but decreased to <0.02% in later periods, corresponding to nitrite accumulation. Methylobacterium (19%) and members of Nitrosomonadaceae (42%) dominated Period III (complete ammonia and partial nitrite oxidation and low NH2Cl residual). An increase in Afipia (haloacetic acid-degrading bacteria) relative abundance (<2% to 42%) occurred during Period IV (minimal nitrification and moderate to high NH2Cl residual). Microbial community and operational data provided no evidence of taxa-time relationship, but rapid community transitions indicated that the system had experienced ecological regime shifts to alternative stable states.
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Affiliation(s)
- Vicente Gomez-Alvarez
- U.S. Environmental Protection Agency, Office of Research and Development, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268, United States
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