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Belykh E, Maystrenko T, Velegzhaninov I, Tavleeva M, Rasova E, Rybak A. Taxonomic Diversity and Functional Traits of Soil Bacterial Communities under Radioactive Contamination: A Review. Microorganisms 2024; 12:733. [PMID: 38674676 PMCID: PMC11051952 DOI: 10.3390/microorganisms12040733] [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: 03/08/2024] [Revised: 03/28/2024] [Accepted: 04/01/2024] [Indexed: 04/28/2024] Open
Abstract
Studies investigating the taxonomic diversity and structure of soil bacteria in areas with enhanced radioactive backgrounds have been ongoing for three decades. An analysis of data published from 1996 to 2024 reveals changes in the taxonomic structure of radioactively contaminated soils compared to the reference, showing that these changes are not exclusively dependent on contamination rates or pollutant compositions. High levels of radioactive exposure from external irradiation and a high radionuclide content lead to a decrease in the alpha diversity of soil bacterial communities, both in laboratory settings and environmental conditions. The effects of low or moderate exposure are not consistently pronounced or unidirectional. Functional differences among taxonomic groups that dominate in contaminated soil indicate a variety of adaptation strategies. Bacteria identified as multiple-stress tolerant; exhibiting tolerance to metals and antibiotics; producing antioxidant enzymes, low-molecular antioxidants, and radioprotectors; participating in redox reactions; and possessing thermophilic characteristics play a significant role. Changes in the taxonomic and functional structure, resulting from increased soil radionuclide content, are influenced by the combined effects of ionizing radiation, the chemical toxicity of radionuclides and co-contaminants, as well as the physical and chemical properties of the soil and the initial bacterial community composition. Currently, the quantification of the differential contributions of these factors based on the existing published studies presents a challenge.
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Affiliation(s)
- Elena Belykh
- Institute of Biology of Komi Scientific Centre, Ural Branch of Russian Academy of Sciences, 28 Kommunisticheskaya St., Syktyvkar 167982, Russia (I.V.); (E.R.)
| | - Tatiana Maystrenko
- Institute of Biology of Komi Scientific Centre, Ural Branch of Russian Academy of Sciences, 28 Kommunisticheskaya St., Syktyvkar 167982, Russia (I.V.); (E.R.)
| | - Ilya Velegzhaninov
- Institute of Biology of Komi Scientific Centre, Ural Branch of Russian Academy of Sciences, 28 Kommunisticheskaya St., Syktyvkar 167982, Russia (I.V.); (E.R.)
| | - Marina Tavleeva
- Institute of Biology of Komi Scientific Centre, Ural Branch of Russian Academy of Sciences, 28 Kommunisticheskaya St., Syktyvkar 167982, Russia (I.V.); (E.R.)
- Department of Biology, Institute of Natural Sciences, Pitirim Sorokin Syktyvkar State University, 55 Oktyabrsky Prospekt, Syktyvkar 167001, Russia
| | - Elena Rasova
- Institute of Biology of Komi Scientific Centre, Ural Branch of Russian Academy of Sciences, 28 Kommunisticheskaya St., Syktyvkar 167982, Russia (I.V.); (E.R.)
| | - Anna Rybak
- Institute of Biology of Komi Scientific Centre, Ural Branch of Russian Academy of Sciences, 28 Kommunisticheskaya St., Syktyvkar 167982, Russia (I.V.); (E.R.)
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Mohanty SR, Mahawar H, Bajpai A, Dubey G, Parmar R, Atoliya N, Devi MH, Singh AB, Jain D, Patra A, Kollah B. Methylotroph bacteria and cellular metabolite carotenoid alleviate ultraviolet radiation-driven abiotic stress in plants. Front Microbiol 2023; 13:899268. [PMID: 36687662 PMCID: PMC9853530 DOI: 10.3389/fmicb.2022.899268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 09/30/2022] [Indexed: 01/07/2023] Open
Abstract
Increasing UV radiation in the atmosphere due to the depletion of ozone layer is emerging abiotic stress for agriculture. Although plants have evolved to adapt to UV radiation through different mechanisms, but the role of phyllosphere microorganisms in counteracting UV radiation is not well studied. The current experiment was undertaken to evaluate the role of phyllosphere Methylobacteria and its metabolite in the alleviation of abiotic stress rendered by ultraviolet (UV) radiation. A potential pink pigmenting methylotroph bacterium was isolated from the phylloplane of the rice plant (oryzae sativa). The 16S rRNA gene sequence of the bacterium was homologous to the Methylobacter sp. The isolate referred to as Methylobacter sp N39, produced beta-carotene at a rate (μg ml-1 d-1) of 0.45-3.09. Biosynthesis of beta-carotene was stimulated by brief exposure to UV for 10 min per 2 days. Carotenoid biosynthesis was predicted as y = 3.09 × incubation period + 22.151 (r 2 = 0.90). The carotenoid extract of N39 protected E. coli from UV radiation by declining its death rate from 14.67% min-1 to 4.30% min-1 under UV radiation. Application of N39 cells and carotenoid extract also protected rhizobium (Bradyrhizobium japonicum) cells from UV radiation. Scanning electron microscopy indicated that the carotenoid extracts protected E. coli cells from UV radiation. Foliar application of either N39 cells or carotenoid extract enhanced the plant's (Pigeon pea) resistance to UV irradiation. This study highlight that Methylobacter sp N39 and its carotenoid extract can be explored to manage UV radiation stress in agriculture.
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Affiliation(s)
- Santosh Ranjan Mohanty
- ICAR-Indian Institute of Soil Science, Bhopal, Madhya Pradesh, India,*Correspondence: Santosh Ranjan Mohanty, ,
| | - Himanshu Mahawar
- ICAR-Indian Institute of Soil Science, Bhopal, Madhya Pradesh, India,ICAR -s Directorate of Weed Research, Jabalpur, Madhya Pradesh, India,Himanshu Mahawar,
| | - Apekcha Bajpai
- ICAR-Indian Institute of Soil Science, Bhopal, Madhya Pradesh, India
| | - Garima Dubey
- ICAR-Indian Institute of Soil Science, Bhopal, Madhya Pradesh, India
| | - Rakesh Parmar
- ICAR-Indian Institute of Soil Science, Bhopal, Madhya Pradesh, India
| | - Nagvanti Atoliya
- ICAR-Indian Institute of Soil Science, Bhopal, Madhya Pradesh, India
| | | | | | - Devendra Jain
- Department of Molecular Biology and Biotechnology, Maharana Pratap University of Agriculture and Technology, Udaipur, Rajasthan, India
| | - Ashok Patra
- ICAR-Indian Institute of Soil Science, Bhopal, Madhya Pradesh, India
| | - Bharati Kollah
- ICAR-Indian Institute of Soil Science, Bhopal, Madhya Pradesh, India,Bharati Kollah, ,
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Koizumi Y, Ichijo T, Uchii K, Nasu M. Changes in bacterial diversity and community structure in drinking water distribution system revealed by high throughput sequencing. JOURNAL OF MICROORGANISM CONTROL 2023; 28:27-34. [PMID: 37277955 DOI: 10.4265/jmc.28.1_27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
For microbiological management of water quality, it is important to identify bacteria and to understand the community structure. To analyze the community structure during water purification and distribution, we selected a distribution system in which water from other water treatment facilities was not mixed with the target water. Changes in the bacterial community structure during treatment and distribution processes in a slow filtration water treatment facility were analyzed using 16S rRNA gene amplicon sequencing with a portable sequencer MinION. The microbial diversity was reduced by chlorination. The genus level diversity increased during distribution and this diversity was maintained through to the terminal tap water. Yersinia and Aeromonas were dominant in the intake water, and Legionella was dominant in the slow sand filtered water. Chlorination greatly reduced the relative abundance of Yersinia, Aeromonas, and Legionella, and these bacteria were not detected in the terminal tap water. Sphingomonas, Starkeya and Methylobacterium became dominant in the water after chlorination. These bacteria could be used as important indicator bacteria to provide useful information for microbiological control in drinking water distribution systems.
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Affiliation(s)
- Yoshihiko Koizumi
- Environmental Health Section, Osaka Institute of Public Health
- Graduate School of Pharmaceutical Sciences, Osaka Ohtani University
| | - Tomoaki Ichijo
- Faculty of Health and Nutrition, Osaka Shoin Women's University
- Graduate School of Human Sciences, Osaka Shoin Women's University
| | | | - Masao Nasu
- Graduate School of Pharmaceutical Sciences, Osaka Ohtani University
- Osaka University
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4
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Pütz E, Gazanis A, Keltsch NG, Jegel O, Pfitzner F, Heermann R, Ternes TA, Tremel W. Communication Breakdown: Into the Molecular Mechanism of Biofilm Inhibition by CeO 2 Nanocrystal Enzyme Mimics and How It Can Be Exploited. ACS NANO 2022; 16:16091-16108. [PMID: 36174231 DOI: 10.1021/acsnano.2c04377] [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] [Indexed: 06/16/2023]
Abstract
Bacterial biofilm formation is a huge problem in industry and medicine. Therefore, the discovery of anti-biofilm agents may hold great promise. Biofilm formation is usually a consequence of bacterial cell-cell communication, a process called quorum sensing (QS). CeO2 nanocrystals (NCs) have been established as haloperoxidase (HPO) mimics and ecologically beneficial biofilm inhibitors. They were suggested to interfere with QS, a mechanism termed quorum quenching (QQ), but their molecular mechanism remained elusive. We show that CeO2 NCs are effective QQ agents, inactivating QS signals by bromination. Catalytic bromination of 3-oxo-C12-AHL a QS signaling compound used by Pseudomonas aeruginosa, was detected in the presence of CeO2 NCs, bromide ions, and hydrogen peroxide. Brominated acyl-homoserine lactones (AHLs) no longer act as QS signals but were not detected in the bacterial cultures. Externally added brominated AHLs also disappeared in P. aeruginosa cultures within minutes of their addition, indicating that they are rapidly degraded by the bacteria. Moreover, we detected the catalytic bromination of 2-heptyl-1-hydroxyquinolin-4(1H)-one (HQNO), a multifunctional non-AHL QS signal from P. aeruginosa with antibacterial and algicidal properties controlling the expression of many virulence genes. Brominated HQNO was not degraded by the bacteria in vivo. The repression of the Pseudomonas quinolone signal (PQS) production and biofilm formation in P. aeruginosa through the catalytic formation of Br-HQNO on surfaces with coatings containing CeO2 enzyme mimics validates the non-toxic strategy for the development of anti-infectives.
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Affiliation(s)
- Eva Pütz
- Department Chemie, Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, D-55128 Mainz, Germany
| | - Athanasios Gazanis
- Mikrobiologie und Biotechnologie, Institut für Molekulare PhysiologieJohannes Gutenberg-Universität Mainz, Biozentrum II, Hanns-Dieter-Hüsch-Weg 17, D-55128 Mainz, Germany
| | - Nils Gert Keltsch
- Bundesanstalt für Gewässerkunde, Am Mainzer Tor 1, D-56068 Koblenz, Germany
| | - Olga Jegel
- Department Chemie, Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, D-55128 Mainz, Germany
| | - Felix Pfitzner
- Department Chemie, Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, D-55128 Mainz, Germany
| | - Ralf Heermann
- Mikrobiologie und Biotechnologie, Institut für Molekulare PhysiologieJohannes Gutenberg-Universität Mainz, Biozentrum II, Hanns-Dieter-Hüsch-Weg 17, D-55128 Mainz, Germany
| | - Thomas A Ternes
- Bundesanstalt für Gewässerkunde, Am Mainzer Tor 1, D-56068 Koblenz, Germany
| | - Wolfgang Tremel
- Department Chemie, Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, D-55128 Mainz, Germany
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Palberg D, Kisiała A, Jorge GL, Emery RJN. A survey of Methylobacterium species and strains reveals widespread production and varying profiles of cytokinin phytohormones. BMC Microbiol 2022; 22:49. [PMID: 35135483 PMCID: PMC8822675 DOI: 10.1186/s12866-022-02454-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 01/21/2022] [Indexed: 12/02/2022] Open
Abstract
Background Symbiotic Methylobacterium strains comprise a significant part of plant microbiomes. Their presence enhances plant productivity and stress resistance, prompting classification of these strains as plant growth-promoting bacteria (PGPB). Methylobacteria can synthesize unusually high levels of plant hormones, called cytokinins (CKs), including the most active form, trans-Zeatin (tZ). Results This study provides a comprehensive inventory of 46 representatives of Methylobacterium genus with respect to phytohormone production in vitro, including 16 CK forms, abscisic acid (ABA) and indole-3-acetic acid (IAA). High performance-liquid chromatography—tandem mass spectrometry (HPLC–MS/MS) analyses revealed varying abilities of Methylobacterium strains to secrete phytohormones that ranged from 5.09 to 191.47 pmol mL−1 for total CKs, and 0.46 to 82.16 pmol mL−1 for tZ. Results indicate that reduced methanol availability, the sole carbon source for bacteria in the medium, stimulates CK secretion by Methylobacterium. Additionally, select strains were able to transform L-tryptophan into IAA while no ABA production was detected. Conclusions To better understand features of CKs in plants, this study uncovers CK profiles of Methylobacterium that are instrumental in microbe selection for effective biofertilizer formulations. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-022-02454-9.
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Affiliation(s)
- Daniel Palberg
- Environmental and Life Sciences Graduate Program, Trent University, 1600 West Bank Drive, Peterborough, ON, K9L 0G2, Canada
| | - Anna Kisiała
- Department of Biology, Trent University, 1600 West Bank Drive, Peterborough, ON, K9L 0G2, Canada.
| | - Gabriel Lemes Jorge
- Department of Biology, Trent University, 1600 West Bank Drive, Peterborough, ON, K9L 0G2, Canada.,Department of Technology, Sao Paulo State University, Jaboticabal, Sao Paulo, Brazil
| | - R J Neil Emery
- Department of Biology, Trent University, 1600 West Bank Drive, Peterborough, ON, K9L 0G2, Canada
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Slightly Acidic Electrolyzed Water to Remove Methylobacterium mesophilicum, Rhodotorula mucilaginosa and Cladosporium cladosporioides in Households. Appl Microbiol 2021. [DOI: 10.3390/applmicrobiol1030039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
(1) Background: Slightly acidic electrolyzed water (SAEW) is an effective and safe sterilizing solution. Its active component is hypochlorous acid (HOCl) which has been proved to exhibit a strong disinfectant activity. In this research we evaluated the effectiveness of SAEW in the removal of Methylobacterium mesophilicum, Rhodotorula mucilaginosa and Cladosporium cladosporioides, responsible for pink-colored biofilm and black mold in households. (2) Methods: Two concentrations of SAEW, 20 mg/L and 40 mg/L, were tested against M. mesophilicum, R. mucilaginosa and C. cladosporioides. In vitro experiments and mesh experiments were conducted to test the effectiveness of SAEW. (3) Results: The test results showed that 40 mg/L SAEW was effective in removing R. mucilaginosa and C. cladosporioides, with the population decreasing by approximately two orders of magnitude. For M. mesophilicum, resistance towards SAEW was observed; to obtain a 1.3 order of magnitude decrease in bacterial population, washing 5 times with 40 mg/L SAEW was necessary. Mesh experiments showed that SAEW can remove black mold; (4) Conclusions: Overall results indicated that SAEW was particularly effective for R. mucilaginosa and C. cladosporioides species commonly found in Japanese households.
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7
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Wang YH, Wu YH, Luo LW, Wang Q, Tong X, Bai Y, Ni XY, Wang HB, Chen GQ, Nozomu I, Chen Z, Hu HY. Metagenomics analysis of the key functional genes related to biofouling aggravation of reverse osmosis membranes after chlorine disinfection. JOURNAL OF HAZARDOUS MATERIALS 2021; 410:124602. [PMID: 33234394 DOI: 10.1016/j.jhazmat.2020.124602] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 11/03/2020] [Accepted: 11/14/2020] [Indexed: 06/11/2023]
Abstract
Chlorine disinfection is a common technology to control biofouling in the pretreatment of the reverse osmosis (RO) system for wastewater reclamation. However, chlorine disinfection could even aggravate the RO membrane biofouling because of the changes of microbial community structure. In this study, the mechanism of biofilm formation and EPS secretion after chlorine disinfection was investigated by analyzing the genes coding quorum sensing, exopolysaccharide biosynthesis, and amino acid biosynthesis. After 1, 5, and 15 mg-Cl2/L chlorine disinfection, the relative abundances of the functional genes all increased significantly. Compared with the control group, chlorine-resistant bacteria (Acidovorax, Arenimonas, and Pseudomonas) also harbored higher relative abundances of these functional genes. The high relative abundances of these genes might provide the bacterial community after chlorine disinfection with high potential of biofilm formation and EPS secretion and then cause severe RO membrane biofouling. In the sample with 5 mg-Cl2/L chlorine disinfection, the correlation coefficients (r) between each two of the three kinds of functional genes were more than 0.9 and much stronger than that in the control group. These results indicated that the bacterial community selected by chlorine disinfection could build more stable biofilm to resist chlorine but also could cause more severe RO membrane biofouling.
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Affiliation(s)
- Yun-Hong Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China.
| | - Li-Wei Luo
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Qi Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xin Tong
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yuan Bai
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xin-Ye Ni
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Hao-Bin Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Gen-Qiang Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Ikuno Nozomu
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen 518055, PR China
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8
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Siedlecka A, Wolf-Baca MJ, Piekarska K. Antibiotic and Disinfectant Resistance in Tap Water Strains - Insight into the Resistance of Environmental Bacteria. Pol J Microbiol 2021; 70:57-67. [PMID: 33815527 PMCID: PMC8008766 DOI: 10.33073/pjm-2021-004] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 12/30/2020] [Accepted: 01/11/2021] [Indexed: 12/15/2022] Open
Abstract
Although antibiotic-resistant bacteria (ARB) have been isolated from tap water worldwide, the knowledge of their resistance patterns is still scarce. Both horizontal and vertical gene transfer has been suggested to contribute to the resistance spread among tap water bacteria. In this study, ARB were isolated from finished water collected at two independent water treatment plants (WTPs) and tap water collected at several point-of-use taps during summer and winter sampling campaigns. A total of 24 strains were identified to genus or species level and subjected to antibiotic and disinfectant susceptibility testing. The investigated tap water ARB belonged to phyla Proteobacteria, Bacteroidetes, Actinobacteria, and Firmicutes. The majority of the isolates proved multidrug resistant and resistant to chemical disinfectant. Neither seasonal nor WTP-dependent variabilities in antibiotic or disinfectant resistance were found. Antibiotics most effective against the investigated isolates included imipenem, tetracyclines, erythromycin, and least effective – aztreonam, cefotaxime, amoxicillin, and ceftazidime. The most resistant strains originate from Afipia sp. and Methylobacterium sp. Comparing resistance patterns of isolated tap water ARB with literature reports concerning the same genera or species confirms intra-genus or even intra-specific variabilities of environmental bacteria. Neither species-specific nor acquired resistance can be excluded.
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Affiliation(s)
- Agata Siedlecka
- Department of Environmental Protection Engineering, Faculty of Environmental Engineering, Wrocław University of Science and Technology, Wrocław, Poland
| | - Mirela J Wolf-Baca
- Department of Environmental Protection Engineering, Faculty of Environmental Engineering, Wrocław University of Science and Technology, Wrocław, Poland
| | - Katarzyna Piekarska
- Department of Environmental Protection Engineering, Faculty of Environmental Engineering, Wrocław University of Science and Technology, Wrocław, Poland
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9
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Osono E, Honda K, Inoue Y, Ichimura K, Kamano C, Akimoto T, Kawamoto S, Norose Y, Takaku S, Morita R. Sodium Hypochlorite is Effective against Biofilms in Dialysis Equipment. Biocontrol Sci 2021; 26:1-7. [PMID: 33716244 DOI: 10.4265/bio.26.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
To test the efficacy of chemical disinfectants against bacterial biofilms in hemodialysis equipment, a Center for Disease Control and Prevention (CDC)-Biofilm Reactor was used to create biofilms. Methylobacterium radiotolerance was isolated from the hemodialysis fluid and used as the test organism. We examined the efficacy of sodium hypochlorite (NaOCl) in elimination of planktonic cells compared to that in the case of biofilms. Planktonic bacteria were completely eliminated at 50 parts per million (ppm) of NaOCl, which is the lowest concentration for clinical use. The viable cell count in the biofilm reached its minimum value around a logarithmic reduction value (LRV) of 6, when the concentration was raised to 1000 ppm and the reaction time was extended by 1 hour or more. Furthermore, at 200 ppm, the LRV was elevated depending on the time. And the LRV while maintaining static conditions for 6 hours at 200 ppm was similar to that of short time at 1000 ppm. These results suggest that NaOCl has sufficient bactericidal activity even for biofilms at a practical concentration and reaction time, and that the CDC-Biofilm Reactor is an effective tool for finding useful disinfection conditions.
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Affiliation(s)
- Eiichi Osono
- Koshigaya Ohbukuro Clinic.,Department of Microbiology and Immunology, Nippon Medical School
| | | | | | | | | | - Toshio Akimoto
- Department of Laboratory Animal Science, Nippon Medical School
| | - Shinya Kawamoto
- Department of Nephrology, Dokkyo Medical University Saitama Medical Center
| | - Yoshihiko Norose
- Department of Microbiology and Immunology, Nippon Medical School
| | - Shun Takaku
- Department of Microbiology and Immunology, Nippon Medical School
| | - Rimpei Morita
- Department of Microbiology and Immunology, Nippon Medical School
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10
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Boaden E, Thomas L, Caroline S, Watkins H. Microbiological analysis of water and thickeners used for people with dysphagia. Br J Community Nurs 2020; 25:S16-S24. [PMID: 32936704 DOI: 10.12968/bjcn.2020.25.sup8.s16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
UNLABELLED Thickened fluids are a recognised intervention strategy in use for people with dysphagia. However, their bacterial profile has not previously been examined. AIMS To identify bacteria and changes in bacterial profiles in a range of water sources and thickener preparations over a 5-day period. METHODS Nine experiments were performed using a range of preparations (sterile, drinking, non-drinking tap water) and a thickening agent (sterile sachet and a used tin). FINDINGS No bacteria were grown on serial subcultures of sterile water, both with and without thickener. Drinking, tap and thickened water left at room temperature for 24 hours may become contaminated with environmental organisms. CONCLUSIONS The growth of bacteria in preparations of thickening agent appears to be dependent upon water quality, while the proliferation of bacteria is dependent upon the length of time the preparation is allowed to stand at room temperature.
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Affiliation(s)
- Elizabeth Boaden
- Senior Research Fellow, the Faculty of Health and Wellbeing, University of Central Lancashire, Preston
| | - Lois Thomas
- Professor of Health Services Research, the Faculty of Health and Wellbeing, University of Central Lancashire, Preston
| | - Susan Caroline
- Professor of Oral Biology, Institute of Population Health Sciences and School of Dentistry, University of Liverpool
| | - Higham Watkins
- Professor of Stroke and Older People's Care, Faculty of Health and Wellbeing, University of Central Lancashire, Preston
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11
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Methylobacterium spp. as Emerging Opportunistic Premise Plumbing Pathogens. Pathogens 2020; 9:pathogens9020149. [PMID: 32098432 PMCID: PMC7168598 DOI: 10.3390/pathogens9020149] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/15/2020] [Accepted: 02/19/2020] [Indexed: 11/29/2022] Open
Abstract
Methylobacterium spp. are emerging opportunistic premise plumbing pathogens. Human infections linked to premise plumbing provide evidence of their routes of infection. Cells of a collection of representative strains of different Methylobacterium species were tested for hydrophobicity by contact angle, adherence and biofilm formation on different plumbing materials, and temperature tolerance (50–60 °C); characteristics shared by OPPPs. Methylobacterium spp. strains were shown to grow in drinking water, have high cell-surface hydrophobicity, adhere to pipe surface materials, form biofilms, and survive exposure to high (60° C) temperatures. It can be concluded that Methylobacterium spp. strains share traits in common with other opportunistic premise plumbing pathogens (OPPPs).
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12
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Tola YH, Fujitani Y, Tani A. Bacteria with natural chemotaxis towards methanol revealed by chemotaxis fishing technique. Biosci Biotechnol Biochem 2019; 83:2163-2171. [PMID: 31272289 DOI: 10.1080/09168451.2019.1637715] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Motile bacteria often exhibit chemotaxis toward favorable compounds. However, the diversity of bacteria that are attracted to a given substance is largely unknown. This study aimed to reveal the diversity of bacteria with natural chemotaxis towards methanol. We tried to enrich environmental chemotactic bacteria using a glass capillary that is half-filled with methanol solidified with agarose as a trap ("chemotaxis fishing"). The pilot experiment using methanol-chemotactic Methylobacterium aquaticum strain 22A enriched the cells by 46-fold. The method was then applied to bacterial suspensions from paddy water and plants. Depending on the isolation sources and the methods of motility induction, methylotrophic bacteria were enriched 1.2-330-fold. The fished isolates belong to 32 species in 18 genera, mainly containing Acinetobacter, Methylobacterium and Pseudomonas species. Our chemotaxis fishing unveiled a part of diversity of the bacteria with natural chemotaxis towards methanol.
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Affiliation(s)
- Yosef Hamba Tola
- Institute of Plant Science and Resources, Okayama University , Kurashiki , Okayama Japan.,Africa-ai-Japan Project at Jomo Kenyatta University of Agriculture and Technology , Nairobi , Kenya.,International Centre of Insect Physiology and Ecology , Nairobi , Kenya
| | - Yoshiko Fujitani
- Institute of Plant Science and Resources, Okayama University , Kurashiki , Okayama Japan
| | - Akio Tani
- Institute of Plant Science and Resources, Okayama University , Kurashiki , Okayama Japan
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13
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Wang YH, Wu YH, Tong X, Yu T, Peng L, Bai Y, Zhao XH, Huo ZY, Ikuno N, Hu HY. Chlorine disinfection significantly aggravated the biofouling of reverse osmosis membrane used for municipal wastewater reclamation. WATER RESEARCH 2019; 154:246-257. [PMID: 30798179 DOI: 10.1016/j.watres.2019.02.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 01/23/2019] [Accepted: 02/09/2019] [Indexed: 06/09/2023]
Abstract
In reverse osmosis (RO) system for wastewater reclamation, biofouling is an inevitable issue. Chlorine disinfection is commonly used in pretreatment to control biofouling. Some chlorine-resistant bacteria could survive after chlorine disinfection and the microbial community structure in feed water changes significantly, thus leading to the change of biofouling potential. In this study, the effect of chlorine disinfection on the biofouling of RO membrane was investigated using a laboratory cross-flow RO system. Chlorine disinfection inactivated most bacteria in feed water. However, during the operation of RO system, with the increase of chlorine dosage the flux decline became more severe after a period of operation. The final normalized flux after 21 days was 0.27, 0.26, 0.20, and 0.21 with 0, 1, 5, and 15 mg-Cl2/L chlorine as pretreatment, respectively. After the operation, the numbers of active bacteria in the foulants on the fouled membrane were on the same level regardless of the chlorine dosage, whereas the thickness of the foulants increased with the chlorine dosage significantly. Additionally, the higher total organic carbon concentration indicated more extracellular polymeric substances (EPS) in foulants. Microbial community structure analysis showed that the abundance and the species number of chlorine-resistant bacteria increased significantly with the chlorine dosage. Typical chlorine-resistant bacteria, including Methylobacterium, Pseudomonas, Sphingomonas, and Acinetobacter, were identified as significantly distinctive genera in the foulants after the pretreatment by 15 mg-Cl2/L chlorine. Compared with the bacteria without chlorine disinfection, these remaining bacteria produced more EPS with higher molecular weight, which could be the major contribution to more severe RO membrane fouling after chlorine disinfection.
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Affiliation(s)
- Yun-Hong Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China.
| | - Xin Tong
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Tong Yu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Lu Peng
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen, 518055, PR China
| | - Yuan Bai
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Xue-Hao Zhao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Zheng-Yang Huo
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Nozomu Ikuno
- Kurita Water Industries Ltd., Nakano-ku, Tokyo, 164-0001, Japan
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen, 518055, PR China.
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14
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First report of Methylobacterium radiotolerans bacteraemia identified by MALDI-TOF mass spectrometry. New Microbes New Infect 2019; 30:100546. [PMID: 31193023 PMCID: PMC6514359 DOI: 10.1016/j.nmni.2019.100546] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/19/2019] [Accepted: 04/02/2019] [Indexed: 11/24/2022] Open
Abstract
Methylobacterium radiotolerans is a fastidious, pink-pigmented, obligate aerobic Gram-negative bacillus commonly isolated from various environmental sources, and only occasionally from clinical samples, mostly in immunocompromised patients or associated with intravascular devices and haemodialysis. It grows poorly on commonly used culture media and its identification is time-consuming by conventional means. In this study, we present a case of M. radiotolerans bacteraemia in an individual affected by end-stage renal failure, identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The species identification was further confirmed by biochemical and molecular methods. The susceptibility to various antimicrobial agents is also presented and discussed.
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15
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Mittelman MW, Jones ADG. A Pure Life: The Microbial Ecology of High Purity Industrial Waters. MICROBIAL ECOLOGY 2018; 76:9-18. [PMID: 26879941 DOI: 10.1007/s00248-016-0736-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 02/01/2016] [Indexed: 06/05/2023]
Abstract
The microbial ecology of various natural environments has been an active area of research since the earlier part of the twentieth century. Remote and sometimes extreme environments such as the deep ocean and the deep terrestrial subsurface have revealed a remarkable array of microorganisms. The majority of these environments are nutrient limited, and microorganisms-principally, bacteria-have developed a number of survival strategies that enable their survival and, in some cases, replication. While planktonic microorganisms exist in oligotrophic environments, the predominant mode of survival and growth is associated with biofilms. There are a number of similarities between the physicochemistry of industrial water systems and some natural aquatic ecosystems, and these similarities extend to the microbial populations and the survival mechanisms that are employed. The "starvation-survival" mechanisms, including biofilm formation, may be associated with deleterious effects on industrial water systems. These effects include heat transfer inhibition, microbially influenced corrosion, and contamination of various products manufactured in a wide array of industries. Biological fouling of industrial water systems has significant direct and indirect (through antimicrobial chemical applications) impacts on engineered materials and on the etiology of some waterborne diseases. This review provides an overview of the microbial ecology of purified waters and discusses the impacts of biological activity on industrial systems.
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Affiliation(s)
- M W Mittelman
- Exponent, 9 Strathmore Rd., Natick, MA, 01760, USA.
- Harvard School of Engineering and Applied Sciences, 58 Oxford St., Rm. 301, Cambridge, MA, 02138, USA.
| | - A D G Jones
- Exponent, 9 Strathmore Rd., Natick, MA, 01760, USA
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16
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Oguma K, Kanazawa K, Kasuga I, Takizawa S. Effects of UV Irradiation by Light Emitting Diodes on Heterotrophic Bacteria in Tap Water. Photochem Photobiol 2018; 94:570-576. [DOI: 10.1111/php.12891] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 12/19/2017] [Indexed: 11/27/2022]
Affiliation(s)
- Kumiko Oguma
- Research Center for Advanced Science and Technology The University of Tokyo Tokyo Japan
| | - Kaori Kanazawa
- Department of Urban Engineering School of Engineering The University of Tokyo Tokyo Japan
| | - Ikuro Kasuga
- Department of Urban Engineering School of Engineering The University of Tokyo Tokyo Japan
| | - Satoshi Takizawa
- Department of Urban Engineering School of Engineering The University of Tokyo Tokyo Japan
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17
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A Keystone Methylobacterium Strain in Biofilm Formation in Drinking Water. WATER 2017. [DOI: 10.3390/w9100778] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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18
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Inhibition of Adherence of Mycobacterium avium to Plumbing Surface Biofilms of Methylobacterium spp. Pathogens 2017; 6:pathogens6030042. [PMID: 28906463 PMCID: PMC5617999 DOI: 10.3390/pathogens6030042] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/06/2017] [Accepted: 09/11/2017] [Indexed: 11/21/2022] Open
Abstract
Both Mycobacterium spp. and Methylobacterium spp. are opportunistic premise plumbing pathogens that are found on pipe surfaces in households. However, examination of data published in prior microbiological surveys indicates that Methylobacterium spp. and Mycobacterium spp. tend not to coexist in the same household plumbing biofilms. That evidence led us to test the hypothesis that Methylobacterium spp. in biofilms could inhibit the adherence of Mycobacterium avium. Measurements of adherence of M. avium cells to stainless steel coupons using both culture and PCR-based methods showed that the presence of Methylobacterium spp. biofilms substantially reduced M. avium adherence and vice versa. That inhibition of M. avium adherence was not reduced by UV-irradiation, cyanide/azide exposure, or autoclaving of the Methylobacterium spp. biofilms. Further, there was no evidence of the production of anti-mycobacterial compounds by biofilm-grown Methylobacterium spp. cells. The results add to understanding of the role of microbial interactions in biofilms as a driving force in the proliferation or inhibition of opportunistic pathogens in premise plumbing, and provide a potential new avenue by which M. avium exposures may be reduced for at-risk individuals.
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19
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Draft Genome Sequence of Methylobacterium sp. Strain ARG-1 Isolated from the White-Rot Fungus Armillaria gallica. GENOME ANNOUNCEMENTS 2016; 4:4/3/e00398-16. [PMID: 27257212 PMCID: PMC4891636 DOI: 10.1128/genomea.00398-16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Methylobacterium sp. strain ARG-1 was isolated from a cell culture of hyphal tips of the white-rot fungus Armillaria gallica. We describe here the sequencing, assembly, and annotation of its genome, confirming the presence of genes involved in methylotrophy. This is the first genome announcement of a strain of Methylobacterium associated with A. gallica.
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Falkinham JO, Williams MD, Kwait R, Lande L. Methylobacterium spp. as an indicator for the presence or absence of Mycobacterium spp. Int J Mycobacteriol 2016; 5:240-3. [PMID: 27242240 DOI: 10.1016/j.ijmyco.2016.03.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 03/05/2016] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE/BACKGROUND A published survey of bacteria in showerhead biofilm samples revealed that Methylobacterium spp. and Mycobacterium spp. seldom coexisted in biofilms. METHODS To confirm that information, biofilm samples were collected from household plumbing of Mycobacterium avium patients and Methylobacterium spp. and M. avium numbers were measured by direct colony counts. RESULTS The results demonstrated that if Methylobacterium spp. were present, Mycobacterium spp. were absent, and the opposite. CONCLUSION The data demonstrate that microbial populations in biofilms can influence the presence or absence of opportunistic premise plumbing pathogens and, thereby, increase the range of strategies to reduce exposure to waterborne pathogens. Finally, by assessing for the visual presence of methylobacteria as pink pigmentation on showers and shower curtains, homeowners and managers of hospitals and other buildings can quickly determine whether a premise plumbing biofilm sample has mycobacteria with a high degree of assurance.
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Affiliation(s)
| | - Myra D Williams
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA
| | - Rebecca Kwait
- Division of Pulmonary and Critical Care Medicine, Lankenau Medical Center, Lankenau Institute for Medical Research, Wynnewood, PA, USA
| | - Leah Lande
- Division of Pulmonary and Critical Care Medicine, Lankenau Medical Center, Lankenau Institute for Medical Research, Wynnewood, PA, USA
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21
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Capelletti RV, Moraes ÂM. Waterborne microorganisms and biofilms related to hospital infections: strategies for prevention and control in healthcare facilities. JOURNAL OF WATER AND HEALTH 2016; 14:52-67. [PMID: 26837830 DOI: 10.2166/wh.2015.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Water is the main stimulus for the development of microorganisms, and its flow has an important role in the spreading of contaminants. In hospitals, the water distribution system requires special attention since it can be a source of pathogens, including those in the form of biofilms often correlated with resistance of microorganisms to various treatments. In this paper, information relevant to cases of nosocomial infections involving water circuits as a source of contaminants is compiled, with emphasis on the importance of microbiological control strategies to prevent the installation, spreading and growth of microorganisms in hospitals. An overview of the worldwide situation is provided, with emphasis on Brazilian hospitals. Different approaches normally used to control the occurrence of nosocomial infections due to waterborne contaminants are analyzed, and the use of the polysaccharide chitosan for this specific application is briefly discussed.
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Affiliation(s)
- Raquel Vannucci Capelletti
- Department of Engineering of Materials and of Bioprocesses, School of Chemical Engineering, University of Campinas (UNICAMP), CEP 13083-852, Campinas, São Paulo, Brazil E-mail:
| | - Ângela Maria Moraes
- Department of Engineering of Materials and of Bioprocesses, School of Chemical Engineering, University of Campinas (UNICAMP), CEP 13083-852, Campinas, São Paulo, Brazil E-mail:
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22
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Choudhury MA, Marsh N, Banu S, Paterson DL, Rickard CM, McMillan DJ. Molecular Comparison of Bacterial Communities on Peripheral Intravenous Catheters and Matched Skin Swabs. PLoS One 2016; 11:e0146354. [PMID: 26731737 PMCID: PMC4701133 DOI: 10.1371/journal.pone.0146354] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 12/16/2015] [Indexed: 11/28/2022] Open
Abstract
Skin bacteria at peripheral intravenous catheter (PIVC) insertion sites pose a serious risk of microbial migration and subsequent colonisation of PIVCs, and the development of catheter related bloodstream infections (CRBSIs). Common skin bacteria are often associated with CRBSIs, therefore the bacterial communities at PIVC skin sites are likely to have major implications for PIVC colonisation. This study aimed to determine the bacterial community structures on skin at PIVC insertion sites and to compare the diversity with associated PIVCs. A total of 10 PIVC skin site swabs and matching PIVC tips were collected by a research nurse from 10 hospitalised medical/surgical patients at catheter removal. All swabs and PIVCs underwent traditional culture and high-throughput sequencing. The bacterial communities on PIVC skin swabs and matching PIVCs were diverse and significantly associated (correlation coefficient = 0.7, p<0.001). Methylobacterium spp. was the dominant genus in all PIVC tip samples, but not so for skin swabs. Sixty-one percent of all reads from the PIVC tips and 36% of all reads from the skin swabs belonged to this genus. Staphylococcus spp., (26%), Pseudomonas spp., (10%) and Acinetobacter spp. (10%) were detected from skin swabs but not from PIVC tips. Most skin associated bacteria commonly associated with CRBSIs were observed on skin sites, but not on PIVCs. Diverse bacterial communities were observed at skin sites despite skin decolonization at PIVC insertion. The positive association of skin and PIVC tip communities provides further evidence that skin is a major source of PIVC colonisation via bacterial migration but microbes present may be different to those traditionally identified via culture methods. The results provide new insights into the colonisation of catheters and potential pathogenesis of bacteria associated with CRBSI, and may assist in developing new strategies designed to reduce the risk of CRBSI.
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Affiliation(s)
- Md Abu Choudhury
- NHMRC Centre of Research Excellence in Nursing (NCREN), Menzies Health Institute Queensland, Griffith University, Brisbane, Australia
- Alliance for Vascular Access Teaching and Research, Griffith University, Brisbane, Australia
- Inflammation and Healing Research Cluster, School of Health and Sports Sciences, University of the Sunshine Coast, Sippy Downs, Brisbane, Australia
| | - Nicole Marsh
- NHMRC Centre of Research Excellence in Nursing (NCREN), Menzies Health Institute Queensland, Griffith University, Brisbane, Australia
- Alliance for Vascular Access Teaching and Research, Griffith University, Brisbane, Australia
- Royal Brisbane and Women’s Hospital, Brisbane, Australia
| | - Shahera Banu
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia
| | - David L. Paterson
- University of Queensland Centre for Clinical Research, Royal Brisbane and Women's Hospital Campus, Brisbane, Australia
| | - Claire M. Rickard
- NHMRC Centre of Research Excellence in Nursing (NCREN), Menzies Health Institute Queensland, Griffith University, Brisbane, Australia
- Alliance for Vascular Access Teaching and Research, Griffith University, Brisbane, Australia
- Royal Brisbane and Women’s Hospital, Brisbane, Australia
| | - David J. McMillan
- Alliance for Vascular Access Teaching and Research, Griffith University, Brisbane, Australia
- Inflammation and Healing Research Cluster, School of Health and Sports Sciences, University of the Sunshine Coast, Sippy Downs, Brisbane, Australia
- * E-mail:
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23
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Pentanol and Benzyl Alcohol Attack Bacterial Surface Structures Differently. Appl Environ Microbiol 2015; 82:402-8. [PMID: 26519389 DOI: 10.1128/aem.02515-15] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 10/22/2015] [Indexed: 12/19/2022] Open
Abstract
The genus Methylobacterium tolerates hygiene agents like benzalkonium chloride (BAC), and infection with this organism is an important public health issue. Here, we found that the combination of BAC with particular alcohols at nonlethal concentrations in terms of their solitary uses significantly reduced bacterial viability after only 5 min of exposure. Among the alcohols, Raman spectroscopic analyses showed that pentanol (pentyl alcohol [PeA]) and benzyl alcohol (BzA) accelerated the cellular accumulation of BAC. Fluorescence spectroscopic assays and morphological assays with giant vesicles indicated that PeA rarely attacked membrane structures, while BzA increased the membrane fluidity and destabilized the structures. Other fluorescent spectroscopic assays indicated that PeA and BzA inactivate bacterial membrane proteins, including an efflux pump for BAC transportation. These findings suggested that the inactivation of membrane proteins by PeA and BzA led to the cellular accumulation but that only BzA also enhanced BAC penetration by membrane fluidization at nonlethal concentrations.
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24
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Falkinham JO. Common features of opportunistic premise plumbing pathogens. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:4533-45. [PMID: 25918909 PMCID: PMC4454924 DOI: 10.3390/ijerph120504533] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 04/20/2015] [Accepted: 04/20/2015] [Indexed: 12/29/2022]
Abstract
Recently it has been estimated that the annual cost of diseases caused by the waterborne pathogens Legionella pneumonia, Mycobacterium avium, and Pseudomonas aeruginosa is $500 million. For the period 2001-2012, the estimated cost of hospital admissions for nontuberculous mycobacterial pulmonary disease, the majority caused by M. avium, was almost $1 billion. These three waterborne opportunistic pathogens are normal inhabitants of drinking water--not contaminants--that share a number of key characteristics that predispose them to survival, persistence, and growth in drinking water distribution systems and premise plumbing. Herein, I list and describe these shared characteristics that include: disinfectant-resistance, biofilm-formation, growth in amoebae, growth at low organic carbon concentrations (oligotrophic), and growth under conditions of stagnation. This review is intended to increase awareness of OPPPs, identify emerging OPPPs, and challenge the drinking water industry to develop novel approaches toward their control.
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Affiliation(s)
- Joseph O Falkinham
- Department of Biological Sciences, Virginia Tech., 1405 Perry Street, Blacksburg, VA 24061, USA.
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25
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Zinchuk A, Zubach O, Zadorozhnyj A, Chudina Y, Bilavka V. Characteristics of Meningitis Due to Methylobacterium mesophilicum: A Rare Case. Jpn J Infect Dis 2015; 68:343-6. [PMID: 25720643 DOI: 10.7883/yoken.jjid.2014.262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Methylobacterium mesophilicum is a gram-negative bacillus most often isolated in medical establishments. In humans, M. mesophilicum is considered a conditionally pathogenic flora. Infections in humans generally occur in immunodeficient individuals. This article describes a rare case of M. mesophilicum infection that developed into acute meningitis in a 26-year-old patient. Decreased neutrophil bactericidal activity was also detected. To our knowledge, there have been no previous reports of meningitis due to M. mesophilicum.
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Affiliation(s)
- Alexander Zinchuk
- Department of Infectious Diseases. Danylo Halytsky Lviv National Medical University
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26
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Troiano F, Polo A, Villa F, Cappitelli F. Assessing the microbiological risk to stored sixteenth century parchment manuscripts: a holistic approach based on molecular and environmental studies. BIOFOULING 2014; 30:299-311. [PMID: 24552245 DOI: 10.1080/08927014.2013.871539] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The microbial risk for the conservation of seven sixteenth century parchment manuscripts, which showed brown discolouration putatively caused by microorganisms, was evaluated using non-invasive sampling techniques, microscopy, studies of surface-associated and airborne microflora with culture-independent molecular methods, and by measuring repository thermo-hygrometric values. Microscopic observations and ATP assays demonstrated a low level of contamination, indicating that the discolouration was not related to currently active microbial colonisation. Nevertheless, a culture-independent molecular approach was adopted to fully characterise surface-associated communities searching for biodeteriogens that could grow under appropriate thermo-hygrometric conditions. Indeed, potential biodeteriogens and microorganisms that are ecologically related to humans were found, suggesting the need to control the conservation environment and improve handling procedures. Microbial loads of air and thermo-hygrometric measurements showed that the repository was not suitable for preventing the microbial deterioration of parchment. A holistic approach to the assessment of risk of microbial deterioration of documents and heritage preservation is proposed for the first time.
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Affiliation(s)
- Federica Troiano
- a a Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente (DeFENS) , Università degli Studi di Milano , Milan , Italy
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Abstract
Methylobacterium species are a cause of health care-associated infection, including infections in immunocompromised hosts. The ability of Methylobacterium species to form biofilms and to develop resistance to high temperatures, drying, and disinfecting agents may explain the colonization of Methylobacterium in the hospital environment in, e.g., endoscopes. Due to its slow growth, it can be easily missed during microbiological surveillance of endoscope reprocessing. The purpose of this minireview is to present an overview of documented infections and cross-contaminations with Methylobacterium related to endoscopic procedures and to illustrate the health care-associated relevance of this slow-growing bacterium.
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Methylobacterium pseudosasae sp. nov., a pink-pigmented, facultatively methylotrophic bacterium isolated from the bamboo phyllosphere. Antonie van Leeuwenhoek 2013; 105:367-76. [PMID: 24297603 DOI: 10.1007/s10482-013-0085-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Accepted: 11/22/2013] [Indexed: 10/26/2022]
Abstract
A pink-pigmented, Gram negative, aerobic, facultatively methylotrophic bacterium, strain BL44(T), was isolated from bamboo leaves and identified as a member of the genus Methylobacterium. Phylogenetic analysis based on 16S rRNA gene sequences showed similarity values of 98.7-97.0 % with closely related type strains and showed highest similarity to Methylobacterium zatmanii DSM 5688(T) (98.7 %) and Methylobacterium thiocyanatum DSM 11490(T) (98.7 %). Methylotrophic metabolism in this strain was confirmed by PCR amplification and sequencing of the mxaF gene coding for the α-subunit of methanol dehydrogenase. Strain BL44(T) produced three known quorum sensing signal molecules with similar retention time to C8, C10 and C12-HSLs when characterized by GC-MS. The fatty acid profiles contained major amounts of C18:1 ω7c, iso-3OH C17:0 and summed feature 3 (C16:1 ω7c and/or iso-C15:0 2-OH), which supported the grouping of the isolate in the genus Methylobacterium. The DNA G+C content was 66.9 mol%. DNA relatedness of the strain BL44(T) to its most closely related strains ranged from 12-43.3 %. On the basis of the phenotypic, phylogenetic and DNA-DNA hybridization data, strain BL44(T) is assigned to a novel species of the genus Methylobacterium for which the name Methylobacterium pseudosasae sp. nov. is proposed (type strain BL44(T) = NBRC 105205(T) = ICMP 17622(T)).
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Mori M, Gomi M, Matsumune N, Niizeki K, Sakagami Y. Biofilm-forming activity of bacteria isolated from toilet bowl biofilms and the bactericidal activity of disinfectants against the isolates. Biocontrol Sci 2013; 18:129-35. [PMID: 24195153 DOI: 10.4265/bio.18.129] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
To evaluate the sanitary conditions of toilets, the bacterial counts of the toilet bowl biofilms in 5 Kansai area and 11 Kansai and Kanto area homes in Japan were measured in winter and summer seasons, respectively. Isolates (128 strains) were identified by analyzing 16S ribosomal RNA sequences. The number of colonies and bacterial species from biofilms sampled in winter tended to be higher and lower, respectively, than those in summer. Moreover, the composition of bacterial communities in summer and winter samples differed considerably. In summer samples, biofilms in Kansai and Kanto areas were dominated by Blastomonas sp. and Mycobacterium sp., respectively. Methylobacterium sp. was detected in all toilet bowl biofilms except for one sample. Methylobacterium sp. constituted the major presence in biofilms along with Brevundimonas sp., Sphingomonas sp., and/or Pseudomonas sp. The composition ratio of the sum of their genera was 88.0 from 42.9% of the total bacterial flora. The biofilm formation abilities of 128 isolates were investigated, and results suggested that Methylobacterium sp. and Sphingomonas sp. were involved in biofilm formation in toilet bowls. The biofilm formation of a mixed bacteria system that included bacteria with the highest biofilm-forming ability in a winter sample was greater than mixture without such bacteria. This result suggests that isolates possessing a high biofilm-forming activity are involved in the biofilm formation in the actual toilet bowl. A bactericidal test against 25 strains indicated that the bactericidal activities of didecyldimethylammonium chloride (DDAC) tended to be higher than those of polyhexamethylene biguanide (PHMB) and N-benzyl-N,N-dimethyldodecylammonium chloride (ADBAC). In particular, DDAC showed high bactericidal activity against approximately 90% of tested strains under the 5 h treatment.
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30
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Piñar G, Garcia-Valles M, Gimeno-Torrente D, Fernandez-Turiel JL, Ettenauer J, Sterflinger K. Microscopic, chemical, and molecular-biological investigation of the decayed medieval stained window glasses of two Catalonian churches. INTERNATIONAL BIODETERIORATION & BIODEGRADATION 2013; 84:388-400. [PMID: 24092957 PMCID: PMC3728567 DOI: 10.1016/j.ibiod.2012.02.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 02/21/2012] [Accepted: 02/22/2012] [Indexed: 05/31/2023]
Abstract
We investigated the decayed historical church window glasses of two Catalonian churches, both under Mediterranean climate. Glass surfaces were studied by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray diffraction (XRD). Their chemical composition was determined by wavelength-dispersive spectrometry (WDS) microprobe analysis. The biodiversity was investigated by molecular methods: DNA extraction from glass, amplification by PCR targeting the16S rRNA and ITS regions, and fingerprint analyses by denaturing gradient gel electrophoresis (DGGE). Clone libraries containing either PCR fragments of the bacterial 16S rDNA or the fungal ITS regions were screened by DGGE. Clone inserts were sequenced and compared with the EMBL database. Similarity values ranged from 89 to 100% to known bacteria and fungi. Biological activity in both sites was evidenced in the form of orange patinas, bio-pitting, and mineral precipitation. Analyses revealed complex bacterial communities consisting of members of the phyla Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. Fungi showed less diversity than bacteria, and species of the genera Cladosporium and Phoma were dominant. The detected Actinobacteria and fungi may be responsible for the observed bio-pitting phenomenon. Moreover, some of the detected bacteria are known for their mineral precipitation capabilities. Sequence results also showed similarities with bacteria commonly found on deteriorated stone monuments, supporting the idea that medieval stained glass biodeterioration in the Mediterranean area shows a pattern comparable to that on stone.
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Affiliation(s)
- Guadalupe Piñar
- Institute of Applied Microbiology, Department of Biotechnology, Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life Sciences, Muthgasse 11, A-1190 Vienna, Austria
| | - Maite Garcia-Valles
- Facultat de Geologia, Universitat de Barcelona (UB), c/ Martí i Franquès s/n, 08028 Barcelona, Spain
| | - Domingo Gimeno-Torrente
- Facultat de Geologia, Universitat de Barcelona (UB), c/ Martí i Franquès s/n, 08028 Barcelona, Spain
| | | | - Jörg Ettenauer
- Institute of Applied Microbiology, Department of Biotechnology, Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life Sciences, Muthgasse 11, A-1190 Vienna, Austria
| | - Katja Sterflinger
- Institute of Applied Microbiology, Department of Biotechnology, Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life Sciences, Muthgasse 11, A-1190 Vienna, Austria
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Bal Krishna KC, Sathasivan A, Ginige MP. Microbial community changes with decaying chloramine residuals in a lab-scale system. WATER RESEARCH 2013; 47:4666-4679. [PMID: 23770481 DOI: 10.1016/j.watres.2013.04.035] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 04/13/2013] [Accepted: 04/18/2013] [Indexed: 06/02/2023]
Abstract
When chloramine is used as a disinfectant, managing an acceptable "residual" throughout the water distribution systems particularly once nitrification has set in is challenging. Managing chloramine decay prior to the onset of nitrification through effective control strategies is important and to-date the strategies developed around nitrification has been ineffective. This study aimed at developing a more holistic knowledge on how decaying chloramine and nitrification metabolites impact microbial communities in chloraminated systems. Five lab-scale reactors (connected in series) were operated to simulate a full-scale chloraminated distribution system. Culture independent techniques (cloning and qPCR) were used to characterise and quantify the mixed microbial communities in reactors maintaining a residual of high to low (2.18-0.03 mg/L). The study for the first time associates chloramine residuals and nitrification metabolites to different microbial communities. Bacterial classes Solibacteres, Nitrospira, Sphingobacteria and Betaproteobacteria dominated at low chloramine residuals whereas Actinobacteria and Gammaproteobacteria dominated at higher chloramine residuals. Prior to the onset of nitrification bacterial genera Pseudomonas, Methylobacterium and Sphingomonas were found to be dominant and Sphingomonas in particular increased with the onset of nitrification. Nitrosomonas urea, oligotropha, and two other novel ammonia-oxidizing bacteria were detected once the chloramine residuals had dropped below 0.65 mg/L. Additionally nitrification alone failed to explain chloramine decay rates observed in these reactors. The finding of this study is expected to re-direct the focus from nitrifiers to heterotrophic bacteria, which the authors believe could hold the key towards developing a control strategy that would enable better management of chloramine residuals.
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Affiliation(s)
- K C Bal Krishna
- Department of Civil and Construction Engineering, Curtin University, GPO Box U1987, Perth, WA 6845, Australia
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Ardley JK, Reeve WG, O'Hara GW, Yates RJ, Dilworth MJ, Howieson JG. Nodule morphology, symbiotic specificity and association with unusual rhizobia are distinguishing features of the genus Listia within the Southern African crotalarioid clade Lotononis s.l. ANNALS OF BOTANY 2013; 112:1-15. [PMID: 23712451 PMCID: PMC3690986 DOI: 10.1093/aob/mct095] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 03/25/2013] [Indexed: 05/02/2023]
Abstract
BACKGROUND AND AIMS The legume clade Lotononis sensu lato (s.l.; tribe Crotalarieae) comprises three genera: Listia, Leobordea and Lotononis sensu stricto (s.s.). Listia species are symbiotically specific and form lupinoid nodules with rhizobial species of Methylobacterium and Microvirga. This work investigated whether these symbiotic traits were confined to Listia by determining the ability of rhizobial strains isolated from species of Lotononis s.l. to nodulate Listia, Leobordea and Lotononis s.s. hosts and by examining the morphology and structure of the resulting nodules. METHODS Rhizobia were characterized by sequencing their 16S rRNA and nodA genes. Nodulation and N2 fixation on eight taxonomically diverse Lotononis s.l. species were determined in glasshouse trials. Nodules of all hosts, and the process of infection and nodule initiation in Listia angolensis and Listia bainesii, were examined by light microscopy. KEY RESULTS Rhizobia associated with Lotononis s.l. were phylogenetically diverse. Leobordea and Lotononis s.s. isolates were most closely related to Bradyrhizobium spp., Ensifer meliloti, Mesorhizobium tianshanense and Methylobacterium nodulans. Listia angolensis formed effective nodules only with species of Microvirga. Listia bainesii nodulated only with pigmented Methylobacterium. Five lineages of nodA were found. Listia angolensis and L. bainesii formed lupinoid nodules, whereas nodules of Leobordea and Lotononis s.s. species were indeterminate. All effective nodules contained uniformly infected central tissue. Listia angolensis and L. bainesii nodule initials occurred on the border of the hypocotyl and along the tap root, and nodule primordia developed in the outer cortical layer. Neither root hair curling nor infection threads were seen. CONCLUSIONS Two specificity groups occur within Lotononis s.l.: Listia species are symbiotically specific, while species of Leobordea and Lotononis s.s. are generally promiscuous and interact with rhizobia of diverse chromosomal and symbiotic lineages. The seasonally waterlogged habitat of Listia species may favour the development of symbiotic specificity.
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Affiliation(s)
- Julie K Ardley
- Centre for Rhizobium Studies, Murdoch University, Murdoch WA 6150, Australia.
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Veyisoglu A, Camas M, Tatar D, Guven K, Sazak A, Sahin N. Methylobacterium tarhaniae sp. nov., isolated from arid soil. Int J Syst Evol Microbiol 2013; 63:2823-2828. [PMID: 23315404 DOI: 10.1099/ijs.0.049551-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A reddish-orange-pigmented, Gram-stain-negative, aerobic, facultatively methylotrophic strain, N4211(T), isolated from arid soil, collected from Abuja, Nigeria, was analysed by using a polyphasic approach. Phylogenetic analysis, based on 16S rRNA gene sequences, showed that strain N4211(T) belonged to the genus Methylobacterium. Strain N4211(T) was most closely related to Methylobacterium aquaticum GR16(T) (98.56 %), Methylobacterium platani PMB02(T) (97.95 %) and Methylobacterium variabile GR3(T) (97.2 %), and the phylogenetic similarities to all other species of the genus Methylobacterium with validly published names were less than 97.0 %. The major ubiquinones detected were Q-10. The major fatty acids were summed feature 7 (C18 : 1 cis11/t9/t6). The DNA G+C content was 67.3 mol%. DNA-DNA relatedness of strain N4211(T) and the most closely related strains M. aquaticum DSM 16371(T) and M. platani KCTC 12901(T) were 60.0 and 48.2 %, respectively. On the basis of phenotypic, phylogenetic and DNA-DNA hybridization data, strain N4211(T) is assigned to a novel species of the genus Methylobacterium for which the name Methylobacterium tarhaniae sp. nov. is proposed. The type strain is N4211(T)( = KCTC 23615(T) = DSM 25844(T)).
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Affiliation(s)
- Aysel Veyisoglu
- Department of Biology, Faculty of Art and Science, Ondokuz Mayis University, 55139 Kurupelit-Samsun, Turkey
| | - Mustafa Camas
- Department of Biology, Faculty of Art and Science, Ondokuz Mayis University, 55139 Kurupelit-Samsun, Turkey
| | - Demet Tatar
- Department of Biology, Faculty of Art and Science, Ondokuz Mayis University, 55139 Kurupelit-Samsun, Turkey
| | - Kiymet Guven
- Department of Biology, Faculty of Science, Anadolu University, Eskisehir-Turkey
| | - Anil Sazak
- Department of Biology, Faculty of Art and Science, Ondokuz Mayis University, 55139 Kurupelit-Samsun, Turkey
| | - Nevzat Sahin
- Department of Biology, Faculty of Art and Science, Ondokuz Mayis University, 55139 Kurupelit-Samsun, Turkey
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Yano T, Kubota H, Hanai J, Hitomi J, Tokuda H. Stress tolerance of Methylobacterium biofilms in bathrooms. Microbes Environ 2012. [PMID: 23207727 PMCID: PMC4070686 DOI: 10.1264/jsme2.me12146] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
A comprehensive survey of microbial flora within pink biofilms in bathrooms was performed. Pink biofilms develop relatively rapidly in bathrooms, can be difficult to remove, and are quick to recur. Bacterium-sized cells were found to be predominant in 42 pink biofilms in Japan using a scanning electron microscope. Methylobacterium strains were detected from all samples in bathrooms by an isolation method. To explain this predominance, 14 biofilm samples were analyzed by fluorescence in situ hybridization. Methylobacterium was indicated to be the major genus in all biofilms. The isolated Methylobacterium survived after contact with 1.0% cleaning agents, including benzalkonium chloride for 24 h. Their tolerance did not differ under biofilm-like conditions on fiber reinforced plastics (FRP), a general material of bath tubs, floors, and walls. Also, the strains exhibited higher tolerance to desiccation than other isolated species on FRP. Some Methylobacterium survived and exhibited potential to grow after four weeks of desiccation without any nutrients. These specific characteristics could be a cause of their predominance in bathrooms, an environment with rapid flowing water, drying, low nutrients, and occasional exposure to cleaning agents.
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Affiliation(s)
- Takehisa Yano
- R&D-Safety Science Research, Kao Corporation, Tochigi, Japan
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ISHINO RYOTA, IEHATA SHUNPEI, NAKANO MIYO, TANAKA REIJI, YOSHIMATSU TAKAO, MAEDA HIROTO. Bacterial Diversity Associated with the Rotifer Brachionus plicatilis sp. Complex Determined by Culture-Dependent and -Independent Methods. Biocontrol Sci 2012; 17:51-6. [DOI: 10.4265/bio.17.51] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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Salka I, Cuperová Z, Mašín M, Koblížek M, Grossart HP. Rhodoferax-related pufM gene cluster dominates the aerobic anoxygenic phototrophic communities in German freshwater lakes. Environ Microbiol 2011; 13:2865-75. [PMID: 21895915 DOI: 10.1111/j.1462-2920.2011.02562.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The presence of aerobic anoxygenic phototrophs (AAPs) has been repeatedly reported from various marine environments, but their distribution in freshwater lakes was neglected until recently. We investigated the phylogenetic composition of AAP communities in 10 lakes in Northeastern Germany with different trophic status including oligotrophic Lake Stechlin and humic matter rich Lake Grosse Fuchskuhle. The AAP community was composed by members of Alpha- and Betaproteobacteria, but their contribution varied largely among the studied lakes. Our results show that AAP community composition in the studied lakes was affected mostly by pH and humic matter content. While alkaline lakes were mostly composed of Betaproteobacteria, the acidic and humic matter rich south-west (SW) basin of Lake Grosse Fuchskule was dominated (87%) by Alphaproteobacteria. The most frequent group within Betaproteobacteria was a cluster of pufM genes which was phylogenetically related to Rhodoferax representing 38.5% of all retrieved sequences. Alphaproteobacteria-related sequences had a broader phylogenetic diversity including six different taxa dominated by Sphingomonas- and Rhodobacter-like bacteria in lakes with alkaline to neutral pH. In the acidic and humic matter-rich SW basin of Lake Grosse Fuchskuhle, however, Methylobacterium-related sequences dominated the AAP community. We suggest that the variable AAP community structure might reflect the potential of these bacteria to cope with the contrasting conditions in freshwater environments.
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Affiliation(s)
- Ivette Salka
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Alte Fischerhütte 2, 16775 Stechlin, Germany
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Endophyte-Assisted Phytoremediation of Explosives in Poplar Trees by Methylobacterium populi BJ001T. ACTA ACUST UNITED AC 2011. [DOI: 10.1007/978-94-007-1599-8_14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Hoppe T, Peters K, Schmidt F. Methylobacterium bullatum sp. nov., a methylotrophic bacterium isolated from Funaria hygrometrica. Syst Appl Microbiol 2011; 34:482-6. [PMID: 21612883 DOI: 10.1016/j.syapm.2010.12.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 11/29/2010] [Accepted: 12/02/2010] [Indexed: 11/28/2022]
Abstract
A novel, pink-pigmented aerobic, facultatively methylotrophic bacterial strain (F3.2(T)) isolated from the phyllosphere of Funaria hygrometrica, was analyzed using a polyphasic approach. Cells were Gram-negative, motile rods, strictly aerobic and non-spore-forming and exhibited surface structures varying in quantity, distribution and morphology. The isolate grew at 10-33°C over a pH range of 5.5-8.0 and in the presence of less than 1.0% NaCl. Strain F3.2(T) shared less than 70% DNA-DNA binding to the next type strain of the genus Methylobacterium (M. adhaesivum DSM 17169(T)). In addition to the major cellular fatty acid C(18:1)ω7c (81.7%), present in all Methylobacterium species (and also members of the genus Alphaproteobacteria), a high value (11.7%) of the fatty acids (summed feature) C(16:1)ω7c and/or iso-C(15:0)2OH was determined. Phylogenetic analyses based on 16S rDNA and methanol dehydrogenase gene sequences, DNA-DNA hybridization values, chemotaxonomic and phenotypic characteristics indicate that the strain F3.2(T) represents a novel species within the genus Methylobacterium. We propose the name Methylobacterium bullatum sp. nov. for this species. The type strain is the strain F3.2(T) (DSM 21893(T)=LMG 24788(T)).
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Affiliation(s)
- Thomas Hoppe
- University of Kassel, Department of Microbiology, FB10, Heinrich-PlettStraße 40, 34109 Kassel, Germany
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FURUHATA KATSUNORI, BANZAI AZUSAU, KAWAKAMI YASUSHI, ISHIZAKI NAOTO, YOSHIDA YOSHIHIRO, GOTO KEIICHI, FUKUYAMA MASAFUMI. Genotyping and Chlorine-Resistance of Methylobacterium aquaticum Isolated from Water Samples in Japan. Biocontrol Sci 2011; 16:103-7. [DOI: 10.4265/bio.16.103] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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HIBI Y, OKUDA M, SAKUMA R, IWAMA T, KAWAI K. Effects of Eu and Sm on Methylobacterium sp.-Growth Behaviors and Expression of Methanol Dehydrogenase-. ACTA ACUST UNITED AC 2011. [DOI: 10.5956/jriet.40.108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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41
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Simões LC, Simões M, Vieira MJ. Influence of the diversity of bacterial isolates from drinking water on resistance of biofilms to disinfection. Appl Environ Microbiol 2010; 76:6673-9. [PMID: 20693444 PMCID: PMC2950458 DOI: 10.1128/aem.00872-10] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Accepted: 08/01/2010] [Indexed: 11/20/2022] Open
Abstract
Single- and multispecies biofilms formed by six drinking water-isolated bacterial species were used to assess their susceptibilities to sodium hypochlorite (SHC). In general, multispecies biofilms were more resistant to inactivation and removal than single biofilms. Total biofilm inactivation was achieved only for Acinetobacter calcoaceticus single-species biofilms and for those multispecies biofilms without A. calcoaceticus. Biofilms with all bacteria had the highest resistance to SHC, while those without A. calcoaceticus were the most susceptible. A. calcoaceticus formed single biofilms susceptible to SHC; however, its presence in multispecies biofilms increased their resistance to disinfection.
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Affiliation(s)
- Lúcia Chaves Simões
- IBB (Institute for Biotechnology and Bioengineering), Centre of Biological Engineering, University of Minho, Braga, Portugal.
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Carducci A, Verani M, Battistini R. Legionella in industrial cooling towers: monitoring and control strategies. Lett Appl Microbiol 2010; 50:24-9. [DOI: 10.1111/j.1472-765x.2009.02750.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Omer ZS, Tombolini R, Gerhardson B. Plant colonization by pink-pigmented facultative methylotrophic bacteria (PPFMs). FEMS Microbiol Ecol 2009; 47:319-26. [PMID: 19712320 DOI: 10.1016/s0168-6496(04)00003-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Bacteria belonging to the genus Methylobacterium are characterized by being able to rely on methanol as a sole carbon and energy source and by presenting a more or less intense pink reddish pigmentation. These bacteria, also referred to as pink-pigmented methylotrophic bacteria (PPFMs), are common inhabitants of the phyllosphere and are found in many other environmental samples. Since they grow slowly they are often overlooked and their impact on phyllosphere microbial communities and on the plants harboring them is not well studied nor has their ecology been elucidated. In a survey of PPFM colonization in three different agricultural sites, PPFM populations were identified on both red clover and winter wheat, but red clover was more consistently colonized. Isolations from collected leaves showed PPFM populations to decrease from spring towards summer, but they increased again towards the end of the cropping season. Isolates from red clover readily colonized winter wheat leaves and vice versa in greenhouse experiments, but population sizes were dependent on the application procedure. Tested isolates had also good potential to colonize the rhizosphere, especially after seed inoculations. Confocal scanning laser microscopy showed gfp-tagged isolates to colonize the surface of clover leaves by forming large aggregates.
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Affiliation(s)
- Zahra S Omer
- Plant Pathology and Biocontrol Unit, Uppsala, Sweden.
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Trotsenko YA, Torgonskaya ML. The aerobic degradation of dichloromethane: Structural-functional aspects (a review). APPL BIOCHEM MICRO+ 2009. [DOI: 10.1134/s0003683809030016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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45
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Zhang P, Lapara TM, Goslan EH, Xie Y, Parsons SA, Hozalski RM. Biodegradation of haloacetic acids by bacterial isolates and enrichment cultures from drinking water systems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:3169-3175. [PMID: 19534130 DOI: 10.1021/es802990e] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Biodegradation is a potentially important loss process for haloacetic acids (HAAs), a class of chlorination byproducts, in water treatment and distribution systems, but little is known about the organisms involved (i.e., identity, substrate range, biodegradation kinetics). In this research, 10 biomass samples (i.e., tap water, distribution system biofilms, and prechlorinated granular activated carbon filters) from nine drinking water systems were used to inoculate a total of thirty enrichment cultures fed monochloroacetic acid (MCAA), dichloroacetic acid (DCAA), or trichloroacetic (TCAA) as sole carbon and energy source. HAA degraders were successfully enriched from the biofilm samples (GAC and distribution system) but rarely from tap water. Half of the MCAA and DCAA enrichment cultures were positive, whereas only one TCAA culture was positive (two were inconclusive). Eight unique HAA-degrading isolates were obtained including several Afipia spp. and a Methylobacterium sp.; all isolates were members of the phylum Proteobacteria. MCAA, monobromoacetic acid (MBAA), and monoiodoacetic acid (MIAA) were rapidly degraded by all isolates, and DCAA and tribromoacetic (TBAA) were also relatively labile. TCAA and dibromoacetic acid (DBAA)were degraded by only three isolates and degradation lagged behind the other HAAs. Detailed DCAA biodegradation kinetics were obtained for two selected isolates and two enrichment cultures. The maximum biomass-normalized degradation rates (Vm) were 0.27 and 0.97 microg DCAA/ microg protein/h for Methylobacterium fujisawaense strain PAWDI and Afipia felis strain EMD2, respectively, which were comparable to the values obtained for the enrichment cultures from which those organisms were isolated (0.39 and 1.37 microg DCAN/microg protein/h, respectively). The half-saturation constant (Km) values ranged from 4.38 to 77.91 microg DCAA/L and the cell yields ranged from 14.4 to 36.1 mg protein/g DCAA.
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Affiliation(s)
- Ping Zhang
- Microbiology and Molecular Genetics, 6120 Biomedical and Physical Sciences, Michigan State University, East Lansing, Michigan 48824, USA
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46
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Hsieh PW, Hsu LC, Lai CH, Wu CC, Hwang TL, Lin YK, Wu YC. Evaluation of the bioactivities of extracts of endophytes isolated from Taiwanese herbal plants. World J Microbiol Biotechnol 2009. [DOI: 10.1007/s11274-009-0036-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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47
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Moissl C, Osman S, La Duc MT, Dekas A, Brodie E, DeSantis T, Desantis T, Venkateswaran K. Molecular bacterial community analysis of clean rooms where spacecraft are assembled. FEMS Microbiol Ecol 2007; 61:509-21. [PMID: 17655710 DOI: 10.1111/j.1574-6941.2007.00360.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Molecular bacterial community composition was characterized from three geographically distinct spacecraft-associated clean rooms to determine whether such populations are influenced by the surrounding environment or the maintenance of the clean rooms. Samples were collected from facilities at the Jet Propulsion Laboratory (JPL), Kennedy Space Flight Center (KSC), and Johnson Space Center (JSC). Nine clone libraries representing different surfaces within the spacecraft facilities and three libraries from the surrounding air were created. Despite the highly desiccated, nutrient-bare conditions within these clean rooms, a broad diversity of bacteria was detected, covering all the main bacterial phyla. Furthermore, the bacterial communities were significantly different from each other, revealing only a small subset of microorganisms common to all locations (e.g. Sphingomonas, Staphylococcus). Samples from JSC assembly room surfaces showed the greatest diversity of bacteria, particularly within the Alpha- and Gammaproteobacteria and Actinobacteria. The bacterial community structure of KSC assembly surfaces revealed a high presence of proteobacterial groups, whereas the surface samples collected from the JPL assembly facility showed a predominance of Firmicutes. Our study presents the first extended molecular survey and comparison of NASA spacecraft assembly facilities, and provides new insights into the bacterial diversity of clean room environments .
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Affiliation(s)
- Christine Moissl
- Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
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Wang X, Sahr F, Xue T, Sun B. Methylobacterium salsuginis sp. nov., isolated from seawater. Int J Syst Evol Microbiol 2007; 57:1699-1703. [PMID: 17684240 DOI: 10.1099/ijs.0.64877-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Three pink-pigmented, facultatively methylotrophic strains, designated MP1, MP2 and MRT, were isolated from seawater from southern China and characterized. Analysis of their complete 16S rRNA gene sequences revealed that they constituted three separate phylogenetic groups, showing the highest levels of similarity with respect to some members of the genus Methylobacterium. PCR amplification also showed the gene coding for the α-subunit of methanol dehydrogenase (mxaF) to be present in all strains, indicating a methylotrophic metabolism. All three strains utilized d-fructose, ethanol and nutrient agar as carbon sources, but did not utilize sucrose, citrate, acetate or formaldehyde. On the basis of the phenotypic, phylogenetic and genotypic analyses, strain MRT represents a novel species, for which the name Methylobacterium salsuginis sp. nov. is proposed, with MRT (=CGMCC 1.6474T =NCCB 100140T) as the type strain. Strains MP1 and MP2 respectively represent novel strains of the species Methylobacterium oryzae and Methylobacterium lusitanum.
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Affiliation(s)
- Xun Wang
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, People's Republic of China
| | - Foday Sahr
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, People's Republic of China
| | - Ting Xue
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, People's Republic of China
| | - Baolin Sun
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, People's Republic of China
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Aslam Z, Lee CS, Kim KH, Im WT, Ten LN, Lee ST. Methylobacterium jeotgali sp. nov., a non-pigmented, facultatively methylotrophic bacterium isolated from jeotgal, a traditional Korean fermented seafood. Int J Syst Evol Microbiol 2007; 57:566-571. [PMID: 17329786 DOI: 10.1099/ijs.0.64625-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A novel facultatively methylotrophic, Gram-negative, rod-shaped bacterium, designated strain S2R03-9(T), was isolated from jeotgal, a traditional Korean fermented seafood. The organism was strictly aerobic, motile by means of a single polar flagellum, non-sporulating and catalase- and oxidase-positive. Strain S2R03-9(T) grew in the presence of 0-1 % (w/v) NaCl and at pH 6.0-10.0, with optimum growth in the absence of NaCl and at pH 7.0. It grew at temperatures in the range 20.0-30.0 degrees C, with optimum growth at 30 degrees C. Colonies grown on R2A medium were non-pigmented, opaque and creamy white. Phylogenetic analysis based on 16S rRNA gene sequences indicated that it was most closely related to Methylobacterium organophilum JCM 2833(T) (96.6 % similarity) and the phylogenetic similarities to all other Methylobacterium species with validly published names were less than 95.0 %. The DNA G+C content was 64.9 mol%. The phylogenetic analysis, the phenotypic assessment and the chemotaxonomic data (major ubiquinone, Q-10; major fatty acids, C(18 : 1) and C(18 : 0)) showed that S2R03-9(T) represents a novel species within the genus Methylobacterium in the class Alphaproteobacteria, for which the name Methylobacterium jeotgali sp. nov. is proposed. The type strain is S2R03-9(T) (=KCTC 12671(T)=LMG 23639(T)).
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Affiliation(s)
- Zubair Aslam
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Chang Soo Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Kyoung-Ho Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Wan-Taek Im
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Leonid N Ten
- Department of Biology and Medicinal Science, Pai Chai University, Daejeon 302-735, Republic of Korea
| | - Sung-Taik Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
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Ikner LA, Toomey RS, Nolan G, Neilson JW, Pryor BM, Maier RM. Culturable microbial diversity and the impact of tourism in Kartchner Caverns, Arizona. MICROBIAL ECOLOGY 2007; 53:30-42. [PMID: 17186153 DOI: 10.1007/s00248-006-9135-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Accepted: 06/27/2006] [Indexed: 05/13/2023]
Abstract
Kartchner Caverns in Benson, AZ, was opened for tourism in 1999 after a careful development protocol that was designed to maintain predevelopment conditions. As a part of an ongoing effort to determine the impact of humans on this limestone cave, samples were collected from cave rock surfaces along the cave trail traveled daily by tour groups (200,000 visitors year-1) and compared to samples taken from areas designated as having medium (30-40 visitors year-1) and low (2-3 visitors year-1) levels of human exposure. Samples were also taken from fiberglass moldings installed during cave development. Culturable bacteria were recovered from these samples and 90 unique isolates were identified by using 16S rRNA polymerase chain reaction and sequencing. Diversity generally decreased as human impact increased leading to the isolation of 32, 27, and 22 strains from the low, medium, and high impact areas, respectively. The degree of human impact was also reflected in the phylogeny of the isolates recovered. Although most isolates fell into one of three phyla: Actinobacteria, Firmicutes, or Proteobacteria, the Proteobacteria were most abundant along the cave trail (77% of the isolates), while Firmicutes predominated in the low (66%) and medium (52%) impact areas. Although the abundance of Proteobacteria along the cave trail seems to include microbes of environmental rather than of anthropogenic origin, it is likely that their presence is a consequence of increased organic matter availability due to lint and other organics brought in by cave visitors. Monitoring of the cave is still in progress to determine whether these bacterial community changes may impact the future development of cave formations.
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Affiliation(s)
- Luisa A Ikner
- Department of Soil, Water and Environmental Science, University of Arizona, 429 Shantz Building #38, Tucson, AZ 85721, USA
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