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Li Y, Huang Z, Zhang H, Zhao J, Du D. Influence of humic acid on the p-tert-Butylphenol removal efficiency by Spirodela polyrhiza-Tas13 association. CHEMOSPHERE 2024; 362:142744. [PMID: 38950749 DOI: 10.1016/j.chemosphere.2024.142744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 06/09/2024] [Accepted: 06/29/2024] [Indexed: 07/03/2024]
Abstract
Plant-microbe remediation technique is considered as a promising technology in removal of organic pollutants and its remediation efficiency is largely affected by a variety of surrounding environmental factors. Humic acid (HA) is the complex organic substance ubiquitous in environment, which characterized by its surfactant-like micelle microstructure and various reaction activity. In our study, a plant-microbe association with high p-tert-Butylphenol (PTBP) degradation potential constructed by Spirodela polyrhiza and Sphingobium phenoxybenzoativorans Tas13 has been used, and the influence of HA on the PTBP degradation efficiency of S. polyrhiza-Tas13 association was investigated. The result showed that the presence of HA greatly improved PTBP removal efficiency of S. polyrhiza-Tas13. The reason accounted for this may be due to the presence of HA promoted bacterial cell propagation, altered bacterial cell wall permeability, increased catechol 2,3-dioxygenase (C23O) enzyme activity of strain Tas13, rather than increasing the colonization ability of strain Tas13 on to the root surface. This study will greatly facilitate the application of aquatic plant-microbe association in environmental remediation.
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Affiliation(s)
- Yan Li
- School of Emergency Management, School of Environment and Safety Engineering, Institute of Environment and Ecology, Jiangsu University, Zhenjiang 212013, People's Republic of China; Jiangsu Province Engineering Research Center of Green Technology and Contingency Management for Emerging Pollutants, Jiangsu University, Zhenjiang 212013, People's Republic of China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou 215009, People's Republic of China.
| | - Zongyan Huang
- School of Emergency Management, School of Environment and Safety Engineering, Institute of Environment and Ecology, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Hui Zhang
- School of Emergency Management, School of Environment and Safety Engineering, Institute of Environment and Ecology, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Jieyu Zhao
- College of Engineering, Peking University, Beijing 100000, People's Republic of China
| | - Daolin Du
- School of Emergency Management, School of Environment and Safety Engineering, Institute of Environment and Ecology, Jiangsu University, Zhenjiang 212013, People's Republic of China; Jingjiang College, School of Agricultural Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
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2
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Mourgela RN, Kioukis A, Pourjam M, Lagkouvardos I. Large-Scale Integration of Amplicon Data Reveals Massive Diversity within Saprospirales, Mostly Originating from Saline Environments. Microorganisms 2023; 11:1767. [PMID: 37512939 PMCID: PMC10384058 DOI: 10.3390/microorganisms11071767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/26/2023] [Accepted: 07/01/2023] [Indexed: 07/30/2023] Open
Abstract
The order Saprospirales, a group of bacteria involved in complex degradation pathways, comprises three officially described families: Saprospiraceae, Lewinellaceae, and Haliscomenobacteraceae. These collectively contain 17 genera and 31 species. The current knowledge on Saprospirales diversity is the product of traditional isolation methods, with the inherited limitations of culture-based approaches. This study utilized the extensive information available in public sequence repositories combined with recent analytical tools to evaluate the global evidence-based diversity of the Saprospirales order. Our analysis resulted in 1183 novel molecular families, 15,033 novel molecular genera, and 188 K novel molecular species. Of those, 7 novel families, 464 novel genera, and 1565 species appeared in abundances at ≥0.1%. Saprospirales were detected in various environments, such as saline water, freshwater, soil, various hosts, wastewater treatment plants, and other bioreactors. Overall, saline water was the environment showing the highest prevalence of Saprospirales, with bioreactors and wastewater treatment plants being the environments where they occurred with the highest abundance. Lewinellaceae was the family containing the majority of the most prevalent species detected, while Saprospiraceae was the family with the majority of the most abundant species found. This analysis should prime researchers to further explore, in a more targeted way, the Saprospirales proportion of microbial dark matter.
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Affiliation(s)
- Rafaila Nikola Mourgela
- School of Chemical and Environmental Engineering, Technical University of Crete, 73100 Chania, Greece
| | - Antonios Kioukis
- Department of Microbiology and Microbial Pathogenesis, School of Medicine, University of Crete, 71500 Heraklion, Greece
| | - Mohsen Pourjam
- ZIEL Institute of Food and Health, Technical University of Munich, 85354 Freising, Germany
| | - Ilias Lagkouvardos
- Department of Microbiology and Microbial Pathogenesis, School of Medicine, University of Crete, 71500 Heraklion, Greece
- ZIEL Institute of Food and Health, Technical University of Munich, 85354 Freising, Germany
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research, 71500 Heraklion, Greece
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3
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Hahn MW, Huemer A, Pitt A, Hoetzinger M. Opening a next-generation black box: Ecological trends for hundreds of species-like taxa uncovered within a single bacterial >99% 16S rRNA operational taxonomic unit. Mol Ecol Resour 2021; 21:2471-2485. [PMID: 34101998 DOI: 10.1111/1755-0998.13444] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 05/10/2021] [Accepted: 06/03/2021] [Indexed: 11/28/2022]
Abstract
Current knowledge on environmental distribution and taxon richness of free-living bacteria is mainly based on cultivation-independent investigations employing 16S rRNA gene sequencing methods. Yet, 16S rRNA genes are evolutionarily rather conserved, resulting in limited taxonomic and ecological resolutions provided by this marker. The faster evolving protein-encoding gene priB was used to reveal ecological patterns hidden within a single operational taxonomic unit (OTU) defined by >99% 16S rRNA sequence similarity. The studied subcluster PnecC of the genus Polynucleobacter represents a ubiquitous group of abundant freshwater bacteria with cosmopolitan distribution, which is very frequently detected by diversity surveys of freshwater systems. Based on genome taxonomy and a large set of genome sequences, a sequence similarity threshold for delineation of species-like taxa could be established. In total, 600 species-like taxa were detected in 99 freshwater habitats scattered across three regions representing a latitudinal range of 3,400 km (42°N to 71°N) and a pH gradient of 4.2 to 8.6. In addition to the unexpectedly high richness, the increased taxonomic resolution revealed structuring of Polynucleobacter communities by a couple of macroecological trends, which was previously only demonstrated for phylogenetically much broader groups of bacteria. An unexpected pattern was the almost complete compositional separation of Polynucleobacter communities of Ca2+ -rich and Ca2+ -poor habitats. This compositional pattern strongly resembled the vicariance of plant species on silicate and limestone soils. The new cultivation-independent approach presented opened a window to an incredible, previously unseen diversity, and enables investigations aiming on deeper understanding of how environmental conditions shape bacterial communities and drive evolution of free-living bacteria.
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Affiliation(s)
- Martin W Hahn
- Research Department for Limnology, University of Innsbruck, Mondsee, Austria
| | - Andrea Huemer
- Research Department for Limnology, University of Innsbruck, Mondsee, Austria
| | - Alexandra Pitt
- Research Department for Limnology, University of Innsbruck, Mondsee, Austria
| | - Matthias Hoetzinger
- Research Department for Limnology, University of Innsbruck, Mondsee, Austria
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4
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Li H, Barber M, Lu J, Goel R. Microbial community successions and their dynamic functions during harmful cyanobacterial blooms in a freshwater lake. WATER RESEARCH 2020; 185:116292. [PMID: 33086464 PMCID: PMC7737503 DOI: 10.1016/j.watres.2020.116292] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/08/2020] [Accepted: 08/10/2020] [Indexed: 05/06/2023]
Abstract
The current study reports the community succession of different toxin and non-toxin producing cyanobacteria at different stages of cyanobacterial harmful algal blooms (CyanoHABs) and their connectivity with nitrogen and phosphorus cycles in a freshwater lake using an ecogenomics framework. Comprehensive high throughput DNA sequencing, water quality parameter measurements, and functional gene expressions over temporal and spatial scales were employed. Among the cyanobacterial community, the lake was initially dominated by Cyanobium during the months of May, June, and early July, and later primarily by Aphanizomenon and Dolichospermum depicting functional redundancy. Finally, Planktothrix appeared in late August and then the dominance switched to Planktothrix in September. Microcystis aeruginosa and Microcystis panniformis; two species responsible for cyanotoxin production, were also present in August and September, but in significantly smaller relative abundance. MC-LR (0.06-1.32 µg/L) and MC-RR (0.01-0.26 µg/L) were two major types of cyanotoxins detected. The presence of MC-LR and MC-RR were significantly correlated with the Microcystis-related genes (16SMic/mcyA/mcyG) and their expressions (r = 0.33 to 0.8, p < 0.05). The metabolic analyses further linked the presence of different cyanobacterial groups with distinct functions. The nitrogen metabolisms detected a relatively higher abundance of nitrite/nitrate reductase in early summer, indicating significant denitrification activity and the activation of N-fixation in the blooms dominated by Aphanizomenon/Dolichospermum (community richness) during nutrient-limited conditions. The phosphorus and carbohydrate metabolisms detected a trend to initiate a nutrient starvation alert and store nutrients from early summer, while utilizing the stored polyphosphate and carbohydrate (PPX and F6PPK) during the extreme ortho-P scarcity period, mostly in August or September. Specifically, the abundance of Aphanizomenon and Dolichospermum was positively correlated with the nitrogen-fixing nif gene and (p < 0.001) and the PPX enzyme for the stored polyphosphate utilization (r = 0.77, p < 0.001). Interestingly, the lake experienced a longer N-fixing period (2-3 months) before non-fixing cyanobacteria (Planktothrix) dominated the entire lake in late summer. The Provo Bay site, which is known to be nutrient-rich historically, had early episodes of filamentous cyanobacteria blooms compared to the rest of the lake.
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Affiliation(s)
- Hanyan Li
- Civil & Environmental Engineering, University of Utah, 110 S. Central Campus Drive, 2000 MCE, Salt Lake City, UT 84121, USA
| | - Mike Barber
- Civil & Environmental Engineering, University of Utah, 110 S. Central Campus Drive, 2000 MCE, Salt Lake City, UT 84121, USA
| | - Jingrang Lu
- United States Environmental Protection Agency, Office of Research and Development, Cincinnati, OH, USA
| | - Ramesh Goel
- Civil & Environmental Engineering, University of Utah, 110 S. Central Campus Drive, 2000 MCE, Salt Lake City, UT 84121, USA.
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5
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Lee ZMP, Poret-Peterson AT, Siefert JL, Kaul D, Moustafa A, Allen AE, Dupont CL, Eguiarte LE, Souza V, Elser JJ. Nutrient Stoichiometry Shapes Microbial Community Structure in an Evaporitic Shallow Pond. Front Microbiol 2017; 8:949. [PMID: 28611750 PMCID: PMC5447685 DOI: 10.3389/fmicb.2017.00949] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 05/11/2017] [Indexed: 11/20/2022] Open
Abstract
Nutrient availability and ratios can play an important role in shaping microbial communities of freshwater ecosystems. The Cuatro Ciénegas Basin (CCB) in Mexico is a desert oasis where, perhaps paradoxically, high microbial diversity coincides with extreme oligotrophy. To better understand the effects of nutrients on microbial communities in CCB, a mesocosm experiment was implemented in a stoichiometrically imbalanced pond, Lagunita, which has an average TN:TP ratio of 122 (atomic). The experiment had four treatments, each with five spatial replicates – unamended controls and three fertilization treatments with different nitrogen:phosphorus (N:P) regimes (P only, N:P = 16 and N:P = 75 by atoms). In the water column, quantitative PCR of the 16S rRNA gene indicated that P enrichment alone favored proliferation of bacterial taxa with high rRNA gene copy number, consistent with a previously hypothesized but untested connection between rRNA gene copy number and P requirement. Bacterial and microbial eukaryotic community structure was investigated by pyrosequencing of 16S and 18S rRNA genes from the planktonic and surficial sediment samples. Nutrient enrichment shifted the composition of the planktonic community in a treatment-specific manner and promoted the growth of previously rare bacterial taxa at the expense of the more abundant, potentially endemic, taxa. The eukaryotic community was highly enriched with phototrophic populations in the fertilized treatment. The sediment microbial community exhibited high beta diversity among replicates within treatments, which obscured any changes due to fertilization. Overall, these results showed that nutrient stoichiometry can be an important factor in shaping microbial community structure.
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Affiliation(s)
- Zarraz M-P Lee
- School of Life Sciences, Arizona State University, TempeAZ, United States
| | | | - Janet L Siefert
- Department of Statistics, Rice University, HoustonTX, United States
| | - Drishti Kaul
- J. Craig Venter Institute, La JollaCA, United States
| | - Ahmed Moustafa
- Department of Biology and Biotechnology Graduate Program, American University in CairoNew Cairo, Egypt
| | - Andrew E Allen
- J. Craig Venter Institute, La JollaCA, United States.,Integrative Oceanography Division, Scripps Institution of Oceanography, University of California, San Diego, La JollaCA, United States
| | | | - Luis E Eguiarte
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de MéxicoCiudad de México, Mexico
| | - Valeria Souza
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de MéxicoCiudad de México, Mexico
| | - James J Elser
- School of Life Sciences, Arizona State University, TempeAZ, United States.,Flathead Lake Biological Station, University of Montana, PolsonMT, United States
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6
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Pernthaler J. Competition and niche separation of pelagic bacteria in freshwater habitats. Environ Microbiol 2017; 19:2133-2150. [PMID: 28370850 DOI: 10.1111/1462-2920.13742] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 03/19/2017] [Accepted: 03/23/2017] [Indexed: 11/29/2022]
Abstract
Freshwater bacterioplankton assemblages are composed of sympatric populations that can be delineated, for example, by ribosomal RNA gene relatedness and that differ in key ecophysiological properties. They may be free-living or attached, specialized for particular concentrations or subsets of substrates, or invest a variable amount of their resources in defence traits against protistan predators and viruses. Some may be motile and tactic whereas others are not, with far-reaching implications for their respective life styles and niche partitioning. The co-occurrence of competitors with overlapping growth requirements has profound consequences for the stability of community functions; it can to some extent be explained by habitat factors such as the microscale complexity and spatiotemporal variability of the lacustrine environments. On the other hand, the composition and diversity of freshwater microbial assemblages also reflects non-equilibrium states, dispersal and the stochasticity of community assembly processes. This review synoptically discusses the competition and niche separation of heterotrophic bacterial populations (defined at various levels of phylogenetic resolution) in the pelagic zone of inland surface waters from a variety of angles, focusing on habitat heterogeneity and the resulting biogeographic distribution patterns, the ecophysiological adaptations to the substrate field and the interactions of prokaryotes with predators and viruses.
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Affiliation(s)
- Jakob Pernthaler
- Limnological Station Kilchberg, Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
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7
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Albert RA, Zitomer D, Dollhopf M, Schauer-Gimenez AE, Struble C, King M, Son S, Langer S, Busse HJ. Proposal of Vibrionimonas magnilacihabitans gen. nov., sp. nov., a curved Gram-stain-negative bacterium isolated from lake water. Int J Syst Evol Microbiol 2014; 64:613-620. [PMID: 24170777 DOI: 10.1099/ijs.0.056663-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A mesophilic bacterium appearing as curved rod-shaped cells was isolated from Lake Michigan water. It exhibited highest similarities with
Sediminibacterium ginsengisoli
DCY13T (94.4 %);
Sediminibacterium salmoneum
NJ-44T (93.6 %) and
Hydrotalea flava
CCUG 51397 T (93.1 %) while similarities with other recognized species were <92.0 %. The primary polar lipid was phosphatidylethanolamine, with moderate amounts of two unidentified glycolipids, three unknown polar lipids, one unknown aminophospholipid and one aminolipid. The primary respiratory quinone was MK-7 and sym-homospermidine was the primary polyamine. The major cellular fatty acids were iso-C15 : 1G, iso-C15 : 0, iso-C16 : 0 3-OH and iso-C17 : 0 3-OH, with moderate amounts of iso-C16 : 0. The presence of glycolipids differentiated the novel strains from related genera. The DNA mol% G+C content of the type strain MU-2T was 45.2. Results for other phenotypic and molecular analyses indicated that strain MU-2T is a representative of a novel genus and species for which the name Vibrionimonas magnilacihabitans is proposed. The type strain is MU-2T ( = NRRL B-59231 = DSM 22423).
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Affiliation(s)
- Richard A. Albert
- Water Quality Center 1515 West Wisconsin Avenue, Marquette University Milwaukee, WI, 53233 USA
| | - Daniel Zitomer
- Water Quality Center 1515 West Wisconsin Avenue, Marquette University Milwaukee, WI, 53233 USA
| | - Michael Dollhopf
- Water Quality Center 1515 West Wisconsin Avenue, Marquette University Milwaukee, WI, 53233 USA
| | - A. E. Schauer-Gimenez
- Water Quality Center 1515 West Wisconsin Avenue, Marquette University Milwaukee, WI, 53233 USA
| | - Craig Struble
- Department of Mathematics, Statistics and Computer Science, P.O. Box 1881, Marquette University, Milwaukee, WI 53201, USA
| | - Michael King
- Microbial Discovery Group 5200 West Ashland Way Franklin, WI, USA
| | - Sona Son
- Microbial Discovery Group 5200 West Ashland Way Franklin, WI, USA
| | - Stefan Langer
- Institute of Bacteriology, Mycology and Hygiene University of Veterinary Medicine Vienna, Veterinärplatz 1, A-1210 Vienna, Austria
| | - Hans-Jürgen Busse
- Institute of Bacteriology, Mycology and Hygiene University of Veterinary Medicine Vienna, Veterinärplatz 1, A-1210 Vienna, Austria
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8
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9
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Albert RA, Waas NE, Pavlons SC, Pearson JL, Ketelboeter L, Rosselló-Móra R, Busse HJ. Sphingobacterium psychroaquaticum sp. nov., a psychrophilic bacterium isolated from Lake Michigan water. Int J Syst Evol Microbiol 2013; 63:952-958. [DOI: 10.1099/ijs.0.043844-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
A psychrophilic, Gram-negative bacterium, designated MOL-1T, was isolated from water of Lake Michigan. 16S rRNA gene sequence analysis revealed that the sequence of strain MOL-1T has sequence similarity of 95.6, 94.8, 94.3, 94.3, 94.2 and 93.9 %, respectively, to the 16S rRNA gene sequences of
Sphingobacterium shayense
HS39T,
S. lactis
WCC 4512T,
S. composti
T5-12T,
S. daejeonense
TR6-04T,
S. bambusae
IBFC2009T and
S. alimentarium
WCC 4521T. The major cellular fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c). Menaquinone MK-7 is the predominant respiratory quinone, while sym-homospermidine is the predominant polyamine. The polar lipid profile is composed of the predominant lipids phosphatidylethanolamine and unidentified polar lipid L2, with moderate amounts of unidentified polar lipids L1, L5 and L6 and unidentified aminophospholipids APL1 and APL2 and minor to trace amounts of unidentified polar lipids L3, L4, L7, L8, L9 and L10, unidentified phospholipid PL4 and unidentified aminophospholipid APL3. After molecular and phenotypic studies, including chemotaxonomic analyses, it was concluded that strain MOL-1T represents a novel
Sphingobacterium
species, for which the name Sphingobacterium psychroaquaticum sp. nov. is proposed. The type strain is MOL-1T ( = NRRL B-59232T = DSM 22418T).
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Affiliation(s)
- Richard A. Albert
- Water Quality Center, Marquette University, Civil & Environmental Engineering, PO Box 1881 Milwaukee, WI 53233, USA
- Kleen Test Products, 1611 Sunset Road, Port Washington, WI 53074, USA
| | - Nancy E. Waas
- Kleen Test Products, 1611 Sunset Road, Port Washington, WI 53074, USA
| | - Shawn C. Pavlons
- Kleen Test Products, 1611 Sunset Road, Port Washington, WI 53074, USA
| | - Jamie L. Pearson
- Kleen Test Products, 1611 Sunset Road, Port Washington, WI 53074, USA
| | - Laura Ketelboeter
- Department of Biological Sciences, UW-Milwaukee, Milwaukee, WI 53201, USA
- Kleen Test Products, 1611 Sunset Road, Port Washington, WI 53074, USA
| | - Ramon Rosselló-Móra
- Grup de Microbiologia Marina, Institut Mediterrani d’Estudis Avançats, Mallorca, E-07190 Esporles, Spain
| | - Hans-Jürgen Busse
- Institute of Bacteriology, Mycology and Hygiene, University of Veterinary Medicine Vienna, Veterinärplatz 1, A-1210 Vienna, Austria
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10
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Jones SE, Cadkin TA, Newton RJ, McMahon KD. Spatial and temporal scales of aquatic bacterial beta diversity. Front Microbiol 2012; 3:318. [PMID: 22969757 PMCID: PMC3431545 DOI: 10.3389/fmicb.2012.00318] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 08/14/2012] [Indexed: 11/15/2022] Open
Abstract
Understanding characteristic variation in aquatic bacterial community composition (BCC) across space and time can inform us about processes driving community assembly and the ability of bacterial communities to respond to perturbations. In this study, we synthesize BCC data from north temperate lakes to evaluate our current understanding of how BCC varies across multiple scales in time and space. A hierarchy of average similarity emerged with the highest similarity found among samples collected within the same lake, especially within the same basin, followed by similarity among samples collected through time within the same lake, and finally similarity among samples collected from different lakes. Using decay of similarity across time and space, we identified equivalent temporal (1 day) and spatial (10 m) scales of BCC variation. Finally, we identify an intriguing pattern of contrasting patterns of intra- and inter-annual BCC variation in two lakes. We argue our synthesis of spatio-temporal variation of aquatic BCC informs expectations for the response of aquatic bacterial communities to perturbation and environmental change. However, further long-term temporal observations will be needed to develop a general understanding of inter-annual BCC variation and our ability to use aquatic BCC as a sensitive metric of environmental change.
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Affiliation(s)
- Stuart E Jones
- Department of Biological Sciences, University of Notre Dame Notre Dame, IN, USA
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11
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Peura S, Eiler A, Hiltunen M, Nykänen H, Tiirola M, Jones RI. Bacterial and phytoplankton responses to nutrient amendments in a boreal lake differ according to season and to taxonomic resolution. PLoS One 2012; 7:e38552. [PMID: 22715392 PMCID: PMC3371014 DOI: 10.1371/journal.pone.0038552] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 05/11/2012] [Indexed: 11/18/2022] Open
Abstract
Nutrient limitation and resource competition in bacterial and phytoplankton communities may appear different when considering different levels of taxonomic resolution. Nutrient amendment experiments conducted in a boreal lake on three occasions during one open water season revealed complex responses in overall bacterioplankton and phytoplankton abundance and biovolume. In general, bacteria were dominant in spring, while phytoplankton was clearly the predominant group in autumn. Seasonal differences in the community composition of bacteria and phytoplankton were mainly related to changes in observed taxa, while the differences across nutrient treatments within an experiment were due to changes in relative contributions of certain higher- and lower-level phylogenetic groups. Of the main bacterioplankton phyla, only Actinobacteria had a treatment response that was visible even at the phylum level throughout the season. With increasing resolution (from 75 to 99% sequence similarity) major responses to nutrient amendments appeared using 454 pyrosequencing data of 16S rRNA amplicons. This further revealed that OTUs (defined by 97% sequence similarity) annotated to the same highly resolved freshwater groups appeared to occur during different seasons and were showing treatment-dependent differentiation, indicating that OTUs within these groups were not ecologically coherent. Similarly, phytoplankton species from the same genera responded differently to nutrient amendments even though biovolumes of the majority of taxa increased when both nitrogen and phosphorus were added simultaneously. The bacterioplankton and phytoplankton community compositions showed concurrent trajectories that could be seen in synchronous succession patterns over the season. Overall, our data revealed that the response of both communities to nutrient changes was highly dependent on season and that contradictory results may be obtained when using different taxonomic resolutions.
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Affiliation(s)
- Sari Peura
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland.
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12
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Jezbera J, Jezberová J, Koll U, Horňák K, Šimek K, Hahn MW. Contrasting trends in distribution of four major planktonic betaproteobacterial groups along a pH gradient of epilimnia of 72 freshwater habitats. FEMS Microbiol Ecol 2012; 81:467-79. [PMID: 22452571 DOI: 10.1111/j.1574-6941.2012.01372.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Revised: 03/16/2012] [Accepted: 03/16/2012] [Indexed: 12/22/2022] Open
Abstract
The distribution and abundance of Betaproteobacteria and three of its genera - Limnohabitans (R-BT065 lineage), Polynucleobacter (including subclusters Polynucleobacter necessarius and Polynucleobacter acidiphobus/Polynucleobacter difficilis), and Methylophilus - across the epilimnia of 72 limnologically diverse freshwater habitats were investigated using fluorescence in situ hybridization. Moreover, seasonal development of Betaproteobacteria subgroups along the longitudinal axis of a reservoir was followed. Betaproteobacteria comprised on average 29.1%, Polynucleobacter 11.6%, P. necessarius 10.1%, P. acidiphobus/difficilis 0.5%, Limnohabitans 8.9%, and Methylophilus 0.9% of total bacterioplankton cells in the investigated habitats. Polynucleobacter necessarius and Limnohabitans coexisted in the majority of habitats but showed contrasting abundance patterns along the pH gradient of habitats (pH, 3.8-8.5). The observed distribution patterns could theoretically be explained by different preferences for substrate sources, that is, substances of humic origin in acidic waters and algal-derived substances in alkaline waters. However, substrate utilization patterns observed in laboratory experiments indicate no coherent group-specific differences in substrate preferences. Interestingly, similar distribution patterns were revealed for Limnohabitans and P. acidiphobus/difficilis, suggesting similar ecological adaptations of these distantly related taxa. Our findings further emphasize that at least two taxa of freshwater Betaproteobacteria represent ecologically diversified groups. Investigations at higher phylogenetic resolution are required for obtaining further insights into their ecology.
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Affiliation(s)
- Jan Jezbera
- Institute for Limnology, Austrian Academy of Sciences, Mondsee, Austria.
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13
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Macrophyte species drive the variation of bacterioplankton community composition in a shallow freshwater lake. Appl Environ Microbiol 2011; 78:177-84. [PMID: 22038598 DOI: 10.1128/aem.05117-11] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Macrophytes play an important role in structuring aquatic ecosystems. In this study, we explored whether macrophyte species are involved in determining the bacterioplankton community composition (BCC) in shallow freshwater lakes. The BCC in field areas dominated by different macrophyte species in Taihu Lake, a large, shallow freshwater lake, was investigated over a 1-year period. Subsequently, microcosm experiments were conducted to determine if single species of different types of macrophytes in an isolated environment would alter the BCC. Denaturing gradient gel electrophoresis (DGGE), followed by cloning and sequence analysis of selected samples, was employed to analyze the BCC. The DGGE results of the field investigations indicated that the BCC changed significantly from season to season and that the presence of different macrophyte species resulted in lower BCC similarities in the summer and fall. LIBSHUFF analysis of selected clone libraries from the summer demonstrated different BCCs in the water column surrounding different macrophytes. Relative to the field observations, the microcosm studies indicated that the BCC differed more pronouncedly when associated with different species of macrophytes, which was also supported by LIBSHUFF analysis of the selected clone libraries. Overall, this study suggested that macrophyte species might be an important factor in determining the composition of bacterial communities in this shallow freshwater lake and that the species-specific influence of macrophytes on BCC is variable with the season and distance.
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Direct and indirect influence of parental bedrock on streambed microbial community structure in forested streams. Appl Environ Microbiol 2011; 77:7681-8. [PMID: 21926206 DOI: 10.1128/aem.06029-11] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A correlative study was performed to determine if variation in streambed microbial community structure in low-order forested streams can be directly or indirectly linked to the chemical nature of the parental bedrock of the environments through which the streams flow. Total microbial and photosynthetic biomass (phospholipid phosphate [PLP] and chlorophyll a), community structure (phospholipid fatty acid analysis), and physical and chemical parameters were measured in six streams, three located in sandstone and three in limestone regions of the Bankhead National Forest in northern Alabama. Although stream water flowing through the two different bedrock types differed significantly in chemical composition, there were no significant differences in total microbial and photosynthetic biomass in the sediments. In contrast, sedimentary microbial community structure differed between the bedrock types and was significantly correlated with stream water ion concentrations. A pattern of seasonal variation in microbial community structure was also observed. Further statistical analysis indicated dissolved organic matter (DOM) quality, which was previously shown to be influenced by geological variation, correlated with variation in bacterial community structure. These results indicate that the geology of underlying bedrock influences benthic microbial communities directly via changes in water chemistry and also indirectly via stream water DOM quality.
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Newton RJ, Jones SE, Eiler A, McMahon KD, Bertilsson S. A guide to the natural history of freshwater lake bacteria. Microbiol Mol Biol Rev 2011; 75:14-49. [PMID: 21372319 PMCID: PMC3063352 DOI: 10.1128/mmbr.00028-10] [Citation(s) in RCA: 860] [Impact Index Per Article: 66.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Freshwater bacteria are at the hub of biogeochemical cycles and control water quality in lakes. Despite this, little is known about the identity and ecology of functionally significant lake bacteria. Molecular studies have identified many abundant lake bacteria, but there is a large variation in the taxonomic or phylogenetic breadths among the methods used for this exploration. Because of this, an inconsistent and overlapping naming structure has developed for freshwater bacteria, creating a significant obstacle to identifying coherent ecological traits among these groups. A discourse that unites the field is sorely needed. Here we present a new freshwater lake phylogeny constructed from all published 16S rRNA gene sequences from lake epilimnia and propose a unifying vocabulary to discuss freshwater taxa. With this new vocabulary in place, we review the current information on the ecology, ecophysiology, and distribution of lake bacteria and highlight newly identified phylotypes. In the second part of our review, we conduct meta-analyses on the compiled data, identifying distribution patterns for bacterial phylotypes among biomes and across environmental gradients in lakes. We conclude by emphasizing the role that this review can play in providing a coherent framework for future studies.
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Affiliation(s)
- Ryan J. Newton
- Great Lakes WATER Institute, University of Wisconsin—Milwaukee, Milwaukee, Wisconsin, Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, Limnology/Department of Ecology & Genetics, Uppsala University, Uppsala, Sweden, Departments of Bacteriology and Civil and Environmental Engineering, University of Wisconsin—Madison, Madison, Wisconsin
| | - Stuart E. Jones
- Great Lakes WATER Institute, University of Wisconsin—Milwaukee, Milwaukee, Wisconsin, Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, Limnology/Department of Ecology & Genetics, Uppsala University, Uppsala, Sweden, Departments of Bacteriology and Civil and Environmental Engineering, University of Wisconsin—Madison, Madison, Wisconsin
| | - Alexander Eiler
- Great Lakes WATER Institute, University of Wisconsin—Milwaukee, Milwaukee, Wisconsin, Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, Limnology/Department of Ecology & Genetics, Uppsala University, Uppsala, Sweden, Departments of Bacteriology and Civil and Environmental Engineering, University of Wisconsin—Madison, Madison, Wisconsin
| | - Katherine D. McMahon
- Great Lakes WATER Institute, University of Wisconsin—Milwaukee, Milwaukee, Wisconsin, Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, Limnology/Department of Ecology & Genetics, Uppsala University, Uppsala, Sweden, Departments of Bacteriology and Civil and Environmental Engineering, University of Wisconsin—Madison, Madison, Wisconsin
| | - Stefan Bertilsson
- Great Lakes WATER Institute, University of Wisconsin—Milwaukee, Milwaukee, Wisconsin, Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, Limnology/Department of Ecology & Genetics, Uppsala University, Uppsala, Sweden, Departments of Bacteriology and Civil and Environmental Engineering, University of Wisconsin—Madison, Madison, Wisconsin
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Jezbera J, Jezberová J, Brandt U, Hahn MW. Ubiquity of Polynucleobacter necessarius subspecies asymbioticus results from ecological diversification. Environ Microbiol 2011; 13:922-31. [PMID: 21208356 PMCID: PMC3087241 DOI: 10.1111/j.1462-2920.2010.02396.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The subspecies Polynucleobacter necessarius asymbioticus (> 99% 16S rRNA similarity) has a cosmopolitan distribution and a ubiquitous occurrence in lentic freshwater habitats. We tested if the observed ubiquity of these free-living planktonic freshwater bacteria results from a euryoecious (generalist) adaptation of P. n. asymbioticus strains, or from ecological diversification within the subspecies. We developed a reverse line blot hybridization assay enabling the cultivation-independent detection of 13 groups within the subspecies in environmental samples. A set of 121 lentic freshwater habitats, spanning a broad variety of habitat types (e.g. pH levels ranging from 3.8 to 8.5) was investigated for the presence of these 13 P. n. asymbioticus groups. Statistical analyses of the reverse line blot hybridization detections revealed pronounced differences in habitat preferences of several of the groups. Their preferences differed regarding pH, conductivity, dissolved organic carbon and oxygen concentration of habitats. For some groups, differences in environmental preferences resulted even in complete niche separation between them. The revealed differences in habitat preferences suggest that the previously reported ubiquity of P. n. asymbioticus results from ecological diversification within the taxon and not from generalist adaptation of strains.
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Affiliation(s)
- Jan Jezbera
- Institute for Limnology, Austrian Academy of Sciences, Mondseestrasse 9, A-5310 Mondsee, Austria.
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Xing P, Guo L, Tian W, Wu QL. Novel Clostridium populations involved in the anaerobic degradation of Microcystis blooms. ISME JOURNAL 2010; 5:792-800. [PMID: 21107445 DOI: 10.1038/ismej.2010.176] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Understanding the microbial degradation of Microcystis biomass is crucial for determining the ecological consequences of Microcystis blooms in freshwater lakes. The purpose of this study was to identify bacteria involved in the anaerobic degradation of Microcystis blooms. Microcystis scum was anaerobically incubated for 90 days at three temperatures (15 °C, 25 °C and 35 °C). We used terminal restriction fragment length polymorphism (T-RFLP) analysis of bacterial 16S rRNA genes, followed by cloning and sequencing of selected samples, to reveal the community composition of bacteria and their dynamics during decomposition. Clostridium spp. were found to be the most dominant bacteria in the incubations, accounting for 72% of the sequenced clones. Eight new clusters or subclusters (designated CLOS.1-8) were identified in the Clostridium phylogenetic tree. The bacterial populations displayed distinct successions during Microcystis decomposition. Temperature had a strong effect on the dynamics of the bacterial populations. At 15 °C, the initial dominance of a 207-bp T-RF (Betaproteobacteria) was largely substituted by a 227-bp T-RF (Clostridium, new cluster CLOS.2) at 30 days. In contrast, at 25 °C and 35 °C, we observed an alternating succession of the 227-bp T-RF and a 231-bp T-RF (Clostridium, new cluster CLOS.1) that occurred more than four times; no one species dominated the flora for the entire experiment. Our study shows that novel Clostridium clusters and their diverse consortiums dominate the bacterial communities during anaerobic degradation of Microcystis, suggesting that these microbes' function in the degradation process.
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Affiliation(s)
- Peng Xing
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, #73 East Beijing Road, Nanjing, Jiangsu, People's Republic of China
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Jezberová J, Jezbera J, Brandt U, Lindström ES, Langenheder S, Hahn MW. Ubiquity of Polynucleobacter necessarius ssp. asymbioticus in lentic freshwater habitats of a heterogeneous 2000 km area. Environ Microbiol 2009; 12:658-69. [PMID: 20041938 DOI: 10.1111/j.1462-2920.2009.02106.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a survey on the distribution and habitat range of Polynucleobacter necessarius ssp. asymbioticus (PnecC), a numerically and functionally important taxon in the plankton of freshwater systems. We systematically sampled stagnant freshwater habitats in a heterogeneous 2000 km(2) area, together with ecologically different habitats outside this area. In total, 137 lakes, ponds and puddles were investigated, which represent an enormous diversity of habitats differing, e.g. in depth (< 10 cm-171 m) and pH (3.9-8.5). PnecC bacteria were detected by cultivation-independent methods in all investigated habitats, and their presence was confirmed by cultivation of strains from selected habitats representing the whole studied ecological range. The determined relative abundance of the subspecies ranged from values close to the detection limit of FISH (0.2%) to 67% (average 14.5%), and the highest observed absolute abundance was 5.3 x 10(6) cells ml(-1). Statistical analyses revealed that the abundance of PnecC bacteria was partially controlled by factors linked to concentrations of humic substances, which support the hypothesis that these bacteria utilize photodegradation products of humic substances. Based on the revealed statistical relationships, an average relative abundance of this subspecies of 20% in global freshwater habitats was extrapolated. Our study provides important implications for the current debate on ubiquity and biogeography in microorganisms.
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Affiliation(s)
- Jitka Jezberová
- Institute for Limnology, Austrian Academy of Sciences, Mondseestrasse 9, A-5310 Mondsee, Austria.
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Albert RA, Waas NE, Langer S, Pavlons SC, Feldner JL, Rosselló-Mora R, Busse HJ. Labrys wisconsinensis sp. nov., a budding bacterium isolated from Lake Michigan water, and emended description of the genus Labrys. Int J Syst Evol Microbiol 2009; 60:1570-1576. [PMID: 19684322 DOI: 10.1099/ijs.0.014977-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Two facultatively anaerobic, budding bacterial strains, designated W1215-PCA4(T) and SRNK-1, were isolated from water from Lake Michigan, USA. The two strains showed identical ERIC-PCR-generated genomic fingerprints and shared 99.9 % 16S rRNA gene sequence similarity. Strain W1215-PCA4(T) showed highest 16S rRNA gene sequence similarities to Labrys monachus VKM B-1479(T) (95.8 %), Labrys methylaminiphilus DSM 16812(T) (95.1 %), Labrys okinawensis MAFF 210191(T) (96.0 %), Labrys miyagiensis G24103(T) (95.4 %), Labrys neptuniae BCRC 17578(T) (95.7 %) and Labrys portucalensis DSM 17916(T) (95.8 %). Data suggested that the two strains were members of a single novel species of the genus Labrys. The major cellular fatty acids of the two isolates were C(18 : 1)omega7c, C(19 : 0) cyclo omega8c and C(16 : 0). Their polar lipid profiles were highly similar to that of Labrys monachus DSM 5896(T). The primary quinone was ubiquinone Q-10, with minor amounts of Q-9 and Q-11. sym-Homospermidine was the predominant polyamine, with putrescine present in moderate amounts. The two strains were identical in terms of their biochemical and physiological traits, but were distinguishable from other species of the genus Labrys. Hence, the description of a novel species in this genus appears to be justified. The name Labrys wisconsinensis sp. nov. is proposed; the type strain is W1215-PCA4(T) (=DSM 19619(T)=NRRL B-51088(T)).
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Affiliation(s)
- Richard A Albert
- Water Quality Center, Marquette University, Civil & Environmental Engineering, PO Box 1881, Milwaukee, Wisconsin, USA.,Kleen Test Products, 1611 Sunset Road, Port Washington, WI 53074, USA
| | - Nancy E Waas
- Kleen Test Products, 1611 Sunset Road, Port Washington, WI 53074, USA
| | - Stefan Langer
- Institute of Bacteriology, Mycology and Hygiene, University of Veterinary Medicine Vienna, Veterinärplatz 1, A-1210 Vienna, Austria
| | - Shawn C Pavlons
- Kleen Test Products, 1611 Sunset Road, Port Washington, WI 53074, USA
| | - Jamie L Feldner
- Kleen Test Products, 1611 Sunset Road, Port Washington, WI 53074, USA
| | - Ramon Rosselló-Mora
- Grup de Microbiologia Marina, Institut Mediterrani d'Estudis Avançats, E-07190 Esporles, Mallorca, Spain
| | - Hans-Jürgen Busse
- Institute of Bacteriology, Mycology and Hygiene, University of Veterinary Medicine Vienna, Veterinärplatz 1, A-1210 Vienna, Austria
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20
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Humbert JF, Dorigo U, Cecchi P, Le Berre B, Debroas D, Bouvy M. Comparison of the structure and composition of bacterial communities from temperate and tropical freshwater ecosystems. Environ Microbiol 2009; 11:2339-50. [PMID: 19508336 DOI: 10.1111/j.1462-2920.2009.01960.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We used a partial 16S rRNA sequencing approach to compare the structure and composition of the bacterial communities in three large, deep subalpine lakes in France with those of communities in six shallow tropical reservoirs in Burkina Faso. Despite the very different characteristics of these ecosystems, we found that their bacterial communities share the same composition in regard to the relative proportions of the different phyla, suggesting that freshwater environmental conditions lead to convergence in this composition. In the same way, we found no significant difference in the richness and diversity of the bacterial communities in France and Burkina Faso. We defined core and satellite operational taxonomic units (OTUs) (sequences sharing at least 98% identity) on the basis of their abundance and their geographical distribution. The core OTUs were found either ubiquitously or only in temperate or tropical and subtropical areas, and they contained more than 70% of all the sequences retrieved in this study. In contrast, satellite OTUs were characterized by having a more restricted geographical distribution and by lower abundance. Finally, the bacterial community composition of these freshwater ecosystems in France and Burkina Faso was markedly different, showing that the history of these ecosystems and regional environmental parameters have a greater impact on the relative abundances of the different OTUs in each bacterial community than the local environmental conditions.
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Affiliation(s)
- Jean-F Humbert
- Institut National de la Recherche Agronomique-UMR 42, BP 511, Thonon Cedex, France.
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Mueller-Spitz SR, Goetz GW, McLellan SL. Temporal and spatial variability in nearshore bacterioplankton communities of Lake Michigan. FEMS Microbiol Ecol 2009; 67:511-22. [PMID: 19220863 DOI: 10.1111/j.1574-6941.2008.00639.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The spatial and temporal variability of bacterial communities were determined for the nearshore waters of Lake Michigan, an oligotrophic freshwater inland sea. A freshwater estuary and nearshore sites were compared six times during 2006 using denaturing gradient gel electrophoresis (DGGE). Bacterial composition clustered by individual site and date rather than by depth. Seven 16S rRNA gene clone libraries were constructed, yielding 2717 bacterial sequences. Spatial variability was detected among the DGGE banding patterns and supported by clone library composition. The clone libraries from deep waters and the estuary environment revealed highest overall bacterial diversity. Betaproteobacteria sequence types were the most dominant taxa, comprising 40.2-67.7% of the clone libraries. BAL 47 was the most abundant freshwater cluster of Betaproteobacteria, indicating widespread distribution of this cluster in the nearshore waters of Lake Michigan. Incertae sedis 5 and Oxalobacteraceae sequence types were prevalent in each clone library, displaying more diversity than previously described in other freshwater environments. Among the Oxalobacteraceae sequences, a globally distributed freshwater cluster was determined. The nearshore waters of Lake Michigan are a dynamic environment that experience forces similar to the coastal ocean environment and share common bacterial diversity with other freshwater habitats.
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WARTON DAVIDI. Raw data graphing: an informative but under-utilized tool for the analysis of multivariate abundances. AUSTRAL ECOL 2008. [DOI: 10.1111/j.1442-9993.2007.01816.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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23
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Allgaier M, Brückner S, Jaspers E, Grossart HP. Intra- and inter-lake variability of free-living and particle-associated Actinobacteria communities. Environ Microbiol 2008; 9:2728-41. [PMID: 17922757 DOI: 10.1111/j.1462-2920.2007.01385.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have analysed the inter- and intra-lake variability of free-living and particle-associated freshwater Actinobacteria communities in four limnological different lakes of the Mecklenburg Lake District, Northeastern Germany. Denaturing gradient gel electrophoresis (DGGE) specific for Actinobacteria was used to investigate phylogenetic diversity and seasonal dynamics of actinobacterial communities in the epilimnion of all lakes (inter-lake variability) and to assess differences between Actinobacteria communities of the epi-, meta- and hypolimnion of a single lake (intra-lake variability) respectively. DGGE analyses showed significant inter- and intra-lake differences between Actinobacteria communities of all lakes and water layers as well as between free-living and particle-associated Actinobacteria. Phylogenetic inferences of 16S rRNA gene sequences suggest that particular members of particle-associated Actinobacteria were exclusively affiliated to certain actinobacterial lineages. The phylogenetic comparison of 16S rRNA gene sequences of all lakes and water layer, however, indicated the occurrence of almost similar phylogenetic lineages in all studied habitats and suggest high intracluster diversity within already known actinobacterial lineages. Non-metric multidimensional scaling (NMS) ordination analyses and Pearson's product moment correlations revealed several strong correlations between the investigated Actinobacteria communities and various limnological parameters, such as conductivity, total phosphorous, alkalinity or primary production. However, no uniform correlation patterns were found between lakes, water layers and bacterial fractions. These heterogeneous correlation patterns together with the phylogenetic similarities of Actinobacteria communities from different lakes indicate that particular Actinobacteria represent various ecotypes or exhibit a pronounced ecophysiological plasticity.
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Affiliation(s)
- Martin Allgaier
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department Limnology of Stratified Lakes, Alte Fischerhütte 2, D-16775 Stechlin-Neuglobsow, Germany
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Abstract
A field study was conducted to determine the microbial community structures of streambed sediments across diverse geographic and climatic areas. Sediment samples were collected from three adjacent headwater forest streams within three biomes, eastern deciduous (Pennsylvania), southeastern coniferous (New Jersey), and tropical evergreen (Guanacaste, Costa Rica), to assess whether there is biome control of stream microbial community structure. Bacterial abundance, microbial biomass, and bacterial and microbial community structures were determined using classical, biochemical, and molecular methods. Microbial biomass, determined using phospholipid phosphate, was significantly greater in the southeastern coniferous biome, likely due to the smaller grain size, higher organic content, and lower levels of physical disturbance of these sediments. Microbial community structure was determined using phospholipid fatty acid (PLFA) profiles and bacterial community structure from terminal restriction fragment length polymorphism and edited (microeukaryotic PLFAs removed) PLFA profiles. Principal component analysis (PCA) was used to investigate patterns in total microbial community structure. The first principal component separated streams based on the importance of phototrophic microeukaryotes within the community, while the second separated southeastern coniferous streams from all others based on increased abundance of fungal PLFAs. PCA also indicated that within- and among-stream variations were small for tropical evergreen streams and large for southeastern coniferous streams. A similar analysis of bacterial community structure indicated that streams within biomes had similar community structures, while each biome possessed a unique streambed community, indicating strong within-biome control of stream bacterial community structure.
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25
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Brendan Logue J, Lindström ES. Biogeography of Bacterioplankton in Inland Waters. ACTA ACUST UNITED AC 2008. [DOI: 10.1608/frj-1.1.9] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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26
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Newton RJ, Jones SE, Helmus MR, McMahon KD. Phylogenetic ecology of the freshwater Actinobacteria acI lineage. Appl Environ Microbiol 2007; 73:7169-76. [PMID: 17827330 PMCID: PMC2168227 DOI: 10.1128/aem.00794-07] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Accepted: 08/27/2007] [Indexed: 11/20/2022] Open
Abstract
The acI lineage of freshwater Actinobacteria is a cosmopolitan and often numerically dominant member of lake bacterial communities. We conducted a survey of acI 16S rRNA genes and 16S-23S rRNA internal transcribed spacer regions from 18 Wisconsin lakes and used standard nonphylogenetic and phylogenetic statistical approaches to investigate the factors that determine acI community composition at the local scale (within lakes) and at the regional scale (across lakes). Phylogenetic reconstruction of 434 acI 16S rRNA genes revealed a well-defined and highly resolved phylogeny. Eleven previously unrecognized monophyletic clades, each with > or =97.9% within-clade 16S rRNA gene sequence identity, were identified. Clade community similarity positively correlated with lake environmental similarity but not with geographic distance, implying that the lakes represent a single biotic region containing environmental filters for communities that have similar compositions. Phylogenetically disparate clades within the acI lineage were most abundant at the regional scale, and local communities were comprised of more closely related clades. Lake pH was a strong predictor of the community composition, but only when lakes with a pH below 6 were included in the data set. In the remaining lakes (pH above 6) biogeographic patterns in the landscape were instead a predictor of the observed acI community structure. The nonrandom distribution of the newly defined acI clades suggests potential ecophysiological differences between the clades, with acI clades AI, BII, and BIII preferring acidic lakes and acI clades AII, AVI, and BI preferring more alkaline lakes.
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Affiliation(s)
- Ryan J Newton
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI 53706, USA
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27
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Wu QL, Zwart G, Wu J, Kamst-van Agterveld MP, Liu S, Hahn MW. Submersed macrophytes play a key role in structuring bacterioplankton community composition in the large, shallow, subtropical Taihu Lake, China. Environ Microbiol 2007; 9:2765-74. [DOI: 10.1111/j.1462-2920.2007.01388.x] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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28
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Hawkins RJ, Purdy KJ. Genotypic distribution of an indigenous model microorganism along an estuarine gradient. FEMS Microbiol Ecol 2007; 62:187-94. [PMID: 17850329 DOI: 10.1111/j.1574-6941.2007.00376.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Using the genus Desulfobulbus as an indigenous model, microbial distribution along an estuarine gradient was investigated. Denaturing gradient gel electrophoresis analysis indicated a sequential change in Desulfobulbus genotypes along the estuary with marine, brackish and freshwater genotypes detected. This differential distribution was significantly correlated with porewater concentrations of chloride, sulphate and nitrate. Temporal analysis indicated that there was a shift in the whole Desulfobulbus community towards to marine end of the estuary by the end of the winter compared with the late summer. This distribution pattern is similar to those seen with other estuarine organisms and, given the correlation with chloride and sulphate, is indicative of classic niche separation within this genus driven by gross environmental factors such as salinity. These results will help in developing a truly ecological description of microbial biodiversity.
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Affiliation(s)
- Robert J Hawkins
- Department of Biological Sciences, University of Reading, Reading, UK
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Hahn MW, Schauer M. 'Candidatus Aquirestis calciphila' and 'Candidatus Haliscomenobacter calcifugiens', filamentous, planktonic bacteria inhabiting natural lakes. Int J Syst Evol Microbiol 2007; 57:936-940. [PMID: 17473236 DOI: 10.1099/ijs.0.64807-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Filamentous bacteria frequently occurring in the pelagic zone of natural freshwater lakes and ponds were previously identified as being related to Haliscomenobacter hydrossis based upon their 16S rRNA gene sequences. These bacteria exhibit a specific morphology characterized by the formation of straight, stick-like filaments of variable length (5 to >100 microm) and quite stable, but narrow, width (0.25 to 0.35 microm). Bacteria with these morphological characteristics form a monophyletic but broad phylogenetic group with a maximal divergence of 16S rRNA gene sequences of 12.0 %. This monophyletic group consists of at least three monophyletic subclusters. H. hydrossis is affiliated to one of these subclusters and represents the sole recognized species affiliated to the broad monophyletic group. 'Candidatus Haliscomenobacter calcifugiens' and 'Candidatus Aquirestis calciphila' are uncultured representatives of the other two subclusters and have 16S rRNA gene sequence dissimilarities of 5.4 % and 8.2 %, respectively, with the type strain of H. hydrossis. 'Candidatus H. calcifugiens' and 'Candidatus A. calciphila' have a 16S rRNA gene sequence dissimilarity of 8.5 %. These large ribosomal divergences justify the classification of these environmentally important bacteria as a novel species and a new genus, respectively. Intensive attempts to cultivate these filamentous bacteria have resulted in the establishment of mixed cultures, however, attempts to establish pure cultures have failed.
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Affiliation(s)
- Martin W Hahn
- Institute for Limnology, Austrian Academy of Sciences, Mondseestrasse 9, 5310 Mondsee, Austria
| | - Michael Schauer
- Institute for Limnology, Austrian Academy of Sciences, Mondseestrasse 9, 5310 Mondsee, Austria
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30
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Harsha TS, Yamakanamardi SM, Mahadevaswamy M. Heterotrophic free-living and particle-bound bacterial cell size in the river Cauvery and its downstream tributaries. J Biosci 2007; 32:363-74. [PMID: 17435327 DOI: 10.1007/s12038-007-0035-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This is the first comprehensive study on planktonic heterotrophic bacterial cell size in the river Cauvery and its important tributaries in Karnataka State, India. The initial hypothesis that the mean cell size of planktonic heterotrophic bacteria in the four tributaries are markedly different from each other and also from that in the main river Cauvery was rejected, because all five watercourses showed similar planktonic heterotrophic bacterial cell size. Examination of the correlation between mean heterotrophic bacterial cell size and environmental variables showed four correlations in the river Arkavathy and two in the river Shimsha. Regression analysis revealed that 18%of the variation in mean heterotrophic free-living bacterial cell size was due to biological oxygen demand (BOD)in the river Arkavathy, 11% due to surface water velocity (SWV)in the river Cauvery and 11% due to temperature in the river Kapila. Heterotrophic particle-bound bacterial cell size variation was 28% due to chloride and BOD in the river Arkavathy, 11% due to conductivity in the river Kapila and 8% due to calcium in the river Cauvery. This type of relationship between heterotrophic bacterial cell size and environmental variables suggests that,though the mean heterotrophic bacterial cell size was similar in all the five water courses, different sets of environmental variables apparently control the heterotrophic bacterial cell size in the various water bodies studied in this investigation. The possible cause for this environmental (bottom -up) control is discussed.
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Affiliation(s)
- T S Harsha
- Aquatic Microbial Ecology Research Laboratory, Department of Studies in Zoology, University of Mysore, Manasagangotri, Mysore 570 006, India
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Vannini C, Pöckl M, Petroni G, Wu QL, Lang E, Stackebrandt E, Schrallhammer M, Richardson PM, Hahn MW. Endosymbiosis in statu nascendi: close phylogenetic relationship between obligately endosymbiotic and obligately free-living Polynucleobacter strains (Betaproteobacteria). Environ Microbiol 2007; 9:347-59. [PMID: 17222133 DOI: 10.1111/j.1462-2920.2006.01144.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bacterial strains affiliated to the phylogenetically shallow subcluster C (PnecC) of the Polynucleobacter cluster, which is characterized by a minimal 16S rRNA gene sequence similarity of approximately 98.5%, have been reported to occur as obligate endosymbionts of ciliates (Euplotes spp.), as well as to occur as free-living cells in the pelagic zone of freshwater habitats. We investigated if these two groups of closely related bacteria represent strains fundamentally differing in lifestyle, or if they simply represent different stages of a facultative endosymbiotic lifestyle. The phylogenetic analysis of 16S rRNA gene and 16S-23S ITS sequences of five endosymbiont strains from two different Euplotes species and 40 pure culture strains demonstrated host-species-specific clustering of the endosymbiont sequences within the PnecC subcluster. The sequences of the endosymbionts showed characteristics indicating an obligate endosymbiotic lifestyle. Cultivation experiments revealed fundamental differences in physiological adaptations, and determination of the genome sizes indicated a slight size reduction in endosymbiotic strains. We conclude that the two groups of PnecC bacteria represent obligately free-living and obligately endosymbiotic strains, respectively, and do not represent different stages of the same complex life cycle. These closely related strains occupy completely separated ecological niches. To our best knowledge, this is the closest phylogenetic relationship between obligate endosymbionts and obligately free-living bacteria ever revealed.
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Affiliation(s)
- Claudia Vannini
- Department of Biology-Protistology and Zoology Unit, University of Pisa, Via A. Volta 4/6, I-56126 Pisa, Italy
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Wu QL, Hahn MW. High predictability of the seasonal dynamics of a species-like Polynucleobacter population in a freshwater lake. Environ Microbiol 2007; 8:1660-6. [PMID: 16913925 DOI: 10.1111/j.1462-2920.2006.01049.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
One of the key questions in microbial ecology is if seasonal patterns of bacterial community composition (BCC) observed in one year repeat in the following years. We have investigated if the recorded annual dynamics of a species-like Polynucleobacter (subcluster PnecB) population allowed the prediction of the population dynamics in another year. The abundance of PnecB bacteria in the pelagic of temperate Lake Mondsee was investigated by fluorescence in situ hybridization (FISH) over three consecutive years. The PnecB bacteria formed a persistent population, and were present in the entire water body of the lake. Two of the three investigated years differed strongly in summer temperatures and precipitation, which resulted in markedly different growth conditions. But despite of these different environmental conditions, the PnecB population demonstrated remarkably similar seasonal dynamics in the three investigated years. Water temperature was the best predictor of the population dynamics during the first half of the annual cycles. Statistical analysis also indicated influences of phytoplankton and metazooplankton successions on the PnecB population dynamics. Furthermore, 65 lakes and ponds were investigated for the presence of PnecB bacteria. They were detected in the majority (78%) of circum-neutral and alkaline freshwater habitats, but not in any investigated acidic or saline habitat.
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Affiliation(s)
- Qinglong L Wu
- Institute for Limnology, Austrian Academy of Sciences, Mondseestrasse 9, A-5310 Mondsee, Austria
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Wu QL, Zwart G, Schauer M, Kamst-van Agterveld MP, Hahn MW. Bacterioplankton community composition along a salinity gradient of sixteen high-mountain lakes located on the Tibetan Plateau, China. Appl Environ Microbiol 2006; 72:5478-85. [PMID: 16885301 PMCID: PMC1538701 DOI: 10.1128/aem.00767-06] [Citation(s) in RCA: 182] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The influence of altitude and salinity on bacterioplankton community composition (BCC) in 16 high-mountain lakes located at altitudes of 2,817 to 5,134 m on the Eastern Qinghai-Xizang (Tibetan) Plateau, China, spanning a salinity gradient from 0.02% (freshwater) to 22.3% (hypersaline), was investigated. Three different methods, fluorescent in situ hybridization, denaturing gradient gel electrophoresis (DGGE) with subsequent band sequencing, and reverse line blot hybridization (RLB) with probes targeting 17 freshwater bacterial groups, were used for analysis of BCC. Furthermore, the salt tolerances of 47 strains affiliated with groups detected in or isolated from the Tibetan habitats were investigated. Altitude was not found to influence BCC significantly within the investigated range. Several groups of typical freshwater bacteria, e.g., the ACK-M1 cluster and the Polynucleobacter group, were detected in habitats located above 4,400 m. Salinity was found to be the dominating environmental factor controlling BCC in the investigated lakes, resulting in only small overlaps in the BCCs of freshwater and hypersaline lakes. The relative abundances of different classes of Proteobacteria showed a sharp succession along the salinity gradient. Both DGGE and RLB demonstrated that a few freshwater bacterial groups, e.g., GKS98 and LD2, appeared over wide salinity ranges. Six freshwater isolates affiliated with the GKS98 cluster grew in ecophysiological experiments at maximum salinities of 0.3% to 0.7% (oligosaline), while this group was detected in habitats with salinities up to 6.7% (hypersaline). This observation indicated ecologically significant differences in ecophysiological adaptations among members of this narrow phylogenetic group and suggested ecological significance of microdiversity.
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Affiliation(s)
- Qinglong L Wu
- Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, East Beijing Road 73, Nanjing 210008, People's Republic of China
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Schauer M, Jiang J, Hahn MW. Recurrent seasonal variations in abundance and composition of filamentous SOL cluster bacteria (Saprospiraceae, Bacteroidetes) in oligomesotrophic Lake Mondsee (Austria). Appl Environ Microbiol 2006; 72:4704-12. [PMID: 16820462 PMCID: PMC1489297 DOI: 10.1128/aem.02935-05] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The spatial and temporal variation of SOL cluster bacteria was assessed in oligomesotrophic Lake Mondsee and adjacent lakes by fluorescence in situ hybridization over two annual cycles. The filamentous SOL bacteria were present in Lake Mondsee throughout the study period, and the seasonal dynamics of the SOL community were remarkably similar with respect to both abundance and composition in the two consecutive years. Only two of the three SOL subclusters were detected in Lake Mondsee and four connected lakes. These two populations significantly differed in size distribution and demonstrated pronounced but recurrent differences in seasonality and length of period of appearance in Lake Mondsee. Extensive sampling of the lakes in September 2003 revealed low horizontal variation in the composition of the SOL community within Lake Mondsee but marked variations with depth. Between connected habitats pronounced differences in the composition and abundance of the SOL community were detected. The interaction of SOL bacteria with bacterivorous protists, mesozooplankton, and phytoplankton was investigated in order to reveal variables controlling the structure and dynamics of SOL communities. No strong indication for a bottom-up influence of phytoplankton was found, while the estimated community grazing rates of mesozooplankton on SOL bacteria indicated a top-down control of SOL abundance during mesozooplankton peaks in spring and early autumn. Furthermore, species-specific differences in grazing of mesozooplankton on SOL bacteria were observed. In general, the overall composition of SOL communities was controlled by abiotic factors (water chemistry), while their dynamics seemed to be controlled by abiotic and biotic interactions.
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Affiliation(s)
- Michael Schauer
- Institute for Limnology, Austrian Academy of Sciences, Mondseestrasse 9, 5310 Mondsee, Austria
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Wu QL, Hahn MW. Differences in structure and dynamics of Polynucleobacter communities in a temperate and a subtropical lake, revealed at three phylogenetic levels. FEMS Microbiol Ecol 2006; 57:67-79. [PMID: 16819951 DOI: 10.1111/j.1574-6941.2006.00105.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The results of ecological studies investigating bacteria by cultivation-independent methods are expected to be influenced by the phylogenetic resolution of the applied molecular tools. This potential influence was investigated in a comparative community study on Polynucleobacter cluster bacteria (Betaproteobacteria) inhabiting the pelagic of the large, shallow, partially hypertrophic Taihu Lake located in subtropical East Asia, and the deep oligo-mesotrophic Lake Mondsee located in temperate Central Europe. The two contrasting habitats were sampled over the same period of 12 months. The community dynamics were investigated at three phylogenetic levels by fluorescent in situ hybridizations with a set of nested probes specific for the beta II clade (including the Polynucleobacter cluster), the genus-like monophyletic Polynucleobacter cluster, and four species-like subclusters. Subcluster B was the numerically dominating subcluster in both lakes over the investigation periods, but demonstrated different population dynamics in the two habitats. Interhabitat comparisons of the Polynucleobacter community structure in the two lakes in the study, and a previously investigated acidic pond indicated ecological diversification within the phylogenetically narrow Polynucleobacter cluster. These results could be obtained by help of the subcluster-specific probes, but would have been missed with probes of a lower phylogenetic resolution.
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Affiliation(s)
- Qinglong L Wu
- Institute for Limnology, Austrian Academy of Sciences, Mondsee, Austria
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Hahn MW. The microbial diversity of inland waters. Curr Opin Biotechnol 2006; 17:256-61. [PMID: 16704930 DOI: 10.1016/j.copbio.2006.05.006] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2006] [Revised: 03/25/2006] [Accepted: 05/04/2006] [Indexed: 10/24/2022]
Abstract
The conservation and sustainable use of freshwater resources is of global importance. Microorganisms are not only the most abundant organisms in natural freshwater systems, but are also key players in ecological processes controlling water quality. Detailed knowledge of the diversity and function of microorganisms dwelling in freshwater habitats is an essential prerequisite for the sustainable management of freshwater resources. Freshwater systems are inhabited by microbial communities that are indigenous to this habitat type and usually do not occur in marine systems, saline inland waters and terrestrial habitats. Despite recent advances in the characterization of the diversity of freshwater microorganisms, knowledge essential for a holistic understanding of their ecological roles is still lacking.
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Affiliation(s)
- Martin W Hahn
- Institute for Limnology, Austrian Academy of Sciences, Mondsee.
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