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Schaible GA, Jay ZJ, Cliff J, Schulz F, Gauvin C, Goudeau D, Malmstrom RR, Emil Ruff S, Edgcomb V, Hatzenpichler R. Multicellular magnetotactic bacterial consortia are metabolically differentiated and not clonal. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.27.568837. [PMID: 38076927 PMCID: PMC10705294 DOI: 10.1101/2023.11.27.568837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2023]
Abstract
Consortia of multicellular magnetotactic bacteria (MMB) are currently the only known example of bacteria without a unicellular stage in their life cycle. Because of their recalcitrance to cultivation, most previous studies of MMB have been limited to microscopic observations. To study the biology of these unique organisms in more detail, we use multiple culture-independent approaches to analyze the genomics and physiology of MMB consortia at single cell resolution. We separately sequenced the metagenomes of 22 individual MMB consortia, representing eight new species, and quantified the genetic diversity within each MMB consortium. This revealed that, counter to conventional views, cells within MMB consortia are not clonal. Single consortia metagenomes were then used to reconstruct the species-specific metabolic potential and infer the physiological capabilities of MMB. To validate genomic predictions, we performed stable isotope probing (SIP) experiments and interrogated MMB consortia using fluorescence in situ hybridization (FISH) combined with nano-scale secondary ion mass spectrometry (NanoSIMS). By coupling FISH with bioorthogonal non-canonical amino acid tagging (BONCAT) we explored their in situ activity as well as variation of protein synthesis within cells. We demonstrate that MMB consortia are mixotrophic sulfate reducers and that they exhibit metabolic differentiation between individual cells, suggesting that MMB consortia are more complex than previously thought. These findings expand our understanding of MMB diversity, ecology, genomics, and physiology, as well as offer insights into the mechanisms underpinning the multicellular nature of their unique lifestyle.
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Affiliation(s)
- George A. Schaible
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717
- Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717
| | - Zackary J. Jay
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717
- Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717
- Thermal Biology Institute, Montana State University, Bozeman, MT 59717
| | - John Cliff
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99354
| | - Frederik Schulz
- Department of Energy Joint Genome Institute, Berkeley, CA, 94720
| | - Colin Gauvin
- Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717
- Thermal Biology Institute, Montana State University, Bozeman, MT 59717
| | - Danielle Goudeau
- Department of Energy Joint Genome Institute, Berkeley, CA, 94720
| | - Rex R. Malmstrom
- Department of Energy Joint Genome Institute, Berkeley, CA, 94720
| | - S. Emil Ruff
- Ecosystems Center and Bay Paul Center, Marine Biological Laboratory, Woods Hole, MA, 02543
| | | | - Roland Hatzenpichler
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717
- Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717
- Thermal Biology Institute, Montana State University, Bozeman, MT 59717
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59717
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2
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Seki Y, Eguchi Y, Taoka A. Influence of protozoan grazing on magnetotactic bacteria on intracellular and extracellular iron content. ENVIRONMENTAL MICROBIOLOGY REPORTS 2023; 15:181-187. [PMID: 36779255 PMCID: PMC10464679 DOI: 10.1111/1758-2229.13140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 12/28/2022] [Indexed: 05/06/2023]
Abstract
Magnetotactic bacteria (MTB) ubiquitously inhabit the oxic-anoxic interface or anaerobic areas of aquatic environments. MTB biomineralize magnetite or greigite crystals and synthesize an organelle known as magnetosome. This intrinsic ability of MTB allows them to accumulate iron to levels 100-1000 times higher than those in non-magnetotactic bacteria (non-MTB). Therefore, MTB considerably contributes to the global iron cycle as primary iron suppliers in the aquatic environmental food chain. However, to the best of our knowledge, there have been no reports describing the effects of trophic interactions between MTB and their protist grazers on the iron distributions in MTB grazers and the extracellular milieu. Herein, we evaluated the effects of MTB grazing using a model species of protist (Tetrahymena pyriformis) and a model species of MTB (Magnetospirillum magneticum AMB-1). MTB-fed T. pyriformis exhibited a magnetic response and contained magnetite crystals in their vacuoles. Fluorescence imaging using a ferrous ion-specific fluorescent dye revealed that the cellular ferrous ion content was five times higher in MTB-fed T. pyriformis than in non-MTB grazers. Moreover, soluble iron concentrations in the spent media increased with time during MTB predation. This study provides experimental evidence to delineate the importance of trophic interactions of MTB on iron distributions.
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Affiliation(s)
- Yusuke Seki
- Institute of Science and EngineeringKanazawa UniversityKakuma‐machi, KanazawaIshikawaJapan
| | - Yukako Eguchi
- Institute for Promotion of Diversity and InclusionKanazawa UniversityKakuma‐machi, KanazawaIshikawaJapan
| | - Azuma Taoka
- Institute of Science and EngineeringKanazawa UniversityKakuma‐machi, KanazawaIshikawaJapan
- Nano Life Science Institute (WPI‐NanoLSI)Kanazawa UniversityKakuma‐machi, KanazawaIshikawaJapan
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3
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Kang X, Lü F, Wang Y, Duan H, Zhang H, He P. Metagenomic analysis of microbiological risk in bioaerosols during biowaste valorization using Musca domestica. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 320:121118. [PMID: 36681377 DOI: 10.1016/j.envpol.2023.121118] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/28/2022] [Accepted: 01/17/2023] [Indexed: 06/17/2023]
Abstract
Bioconversion using insects has gradually become a promising technology for biowaste management and protein production. However, knowledge about microbiological risk of insect related bioaerosols is sparse and conventional methods failed to provide higher resolved information of environmental microbe. In this study, a metagenomic analysis including microorganisms, antibiotic resistance genes (ARGs), virulence factor genes (VFGs), mobile gene elements (MGEs), and endotoxin distribution in bioaerosols during biowaste conversion via Musca domestica revealed that bioaerosols in Fly rearing room possess the highest ARGs abundances and MGEs diversity. Through a metagenome-assembled genomes (MAGs)-based pipeline, compelling evidence of ARGs/VFGs host assignment and ARG-VFG co-occurrence pattern were provided from metagenomic perspective. Bioaerosols in Bioconversion and Maggot separation zone were identified to own high density of MAGs carrying both ARGs and VFGs. Bacteria in Proteobacteria, Actinobacteriota, and Firmicutes phyla were predominate hosts of ARGs and VFGs. Multidrug-Motility, Multidrug-Adherence, and Beta lactam-Motility pairs were the most common ARG-VFG co-occurrence pattern in this study. Results obtained are of great significance for microbiological risk assessment during housefly biowaste conversion process.
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Affiliation(s)
- Xinyue Kang
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Fan Lü
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-processing and Energy Utilization, Shanghai 200092, China
| | - Yujing Wang
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Haowen Duan
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Hua Zhang
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-processing and Energy Utilization, Shanghai 200092, China
| | - Pinjing He
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-processing and Energy Utilization, Shanghai 200092, China.
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4
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Mandal FB. Interaction between marine protists and bacteria results in magnetotaxis and iron recycling. Isr J Ecol Evol 2022. [DOI: 10.1163/22244662-bja10042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Abstract
Marine protists are eukaryotic trophic linkers that play a crucial role in iron recycling. Some marine protists have the ability of magnetotaxis, which they gain by consuming their ectosymbiotic bacteria. They graze and internalize the magnetotactic bacteria along with their magnetosome chains. Through egestion, marine protists avoid iron toxicity. Colloidal iron digestion by protists produces bioavailable iron for other marine organisms, passing to phytoplankton and mesozooplankton through the mesotrophic system. Indeed, ectosymbiotic bacteria and their protistan host form a microbial holobiont acting as an ecological unit. Some of the genetic mechanisms influencing the biosynthesis of magnetite in both prokaryotes and eukaryotes appear to be common. The recorded history of the magnetoreception ability of some marine protists goes back to the study by F.F. Torres de Araujo in 1986. After research over 35 years or more, it is safe to record that magnetotaxis in marine protists is yet to be fully understood, and might be similar to that of free-living magnetotactic bacteria. However, the attainment of magnetotaxis by protistan grazers through bacterivory and its role in iron recycling in the marine ecosystem is very interesting. The present article aims to provide an account of such interesting facts.
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Affiliation(s)
- Fatik Baran Mandal
- Department of Zoology, Bankura Christian College, College Road, Bankura, West Bengal, 722101, India
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Sehein TR, Gast RJ, Pachiadaki M, Guillou L, Edgcomb VP. Parasitic infections by Group II Syndiniales target selected dinoflagellate host populations within diverse protist assemblages in a model coastal pond. Environ Microbiol 2022; 24:1818-1834. [PMID: 35315564 DOI: 10.1111/1462-2920.15977] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 03/13/2022] [Indexed: 11/29/2022]
Abstract
Protists are integral to marine food webs and biogeochemical cycles; however, there is a paucity of data describing specific ecological niches for some of the most abundant taxa in marker gene libraries. Syndiniales are one such group, often representing the majority of sequence reads recovered from picoplankton samples across the global ocean. However, the prevalence and impacts of syndinian parasitism in marine environments remains unclear. We began to address these critical knowledge gaps by generating a high-resolution time series (March-October 2018) in a productive coastal pond. Seasonal shifts in protist populations, including parasitic Syndiniales, were documented during periods of higher primary productivity and increased summer temperature-driven stratification. Elevated concentrations of infected hosts and free-living parasite spores occurred at nearly monthly intervals in July, August, and September. We suggest intensifying stratification during this period correlated with the increased prevalence of dinoflagellates that were parasitized by Group II Syndiniales. Infections in some protist populations were comparable to previously reported large single-taxon dinoflagellate blooms. Infection dynamics in Salt Pond demonstrated the propagation of syndinian parasites through mixed protist assemblages and highlighted patterns of host/parasite interactions that better reflect many other marine environments where single taxon blooms are uncommon.
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Affiliation(s)
- Taylor R Sehein
- MIT-WHOI Joint Program in Biological Oceanography, Cambridge and Woods Hole, MA, United States
| | - Rebecca J Gast
- Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Maria Pachiadaki
- Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Laure Guillou
- Sorbonne Université & Centre National pour la Recherche Scientifique, Station Biologique de Roscoff, UMR7144, Roscoff, France
| | - Virginia P Edgcomb
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
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6
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Keim CN, da Silva DM, de Melo RD, Acosta-Avalos D, Farina M, de Barros HL. Swimming behavior of the multicellular magnetotactic prokaryote 'Candidatus Magnetoglobus multicellularis' near solid boundaries and natural magnetic grains. Antonie van Leeuwenhoek 2021; 114:1899-1913. [PMID: 34478018 DOI: 10.1007/s10482-021-01649-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 08/24/2021] [Indexed: 11/26/2022]
Abstract
The magnetotactic yet uncultured species 'Candidatus Magnetoglobus multicellularis' is a spherical, multicellular ensemble of bacterial cells able to align along magnetic field lines while swimming propelled by flagella. Magnetotaxis is due to intracytoplasmic, membrane-bound magnetic crystals called magnetosomes. The net magnetic moment of magnetosomes interacts with local magnetic fields, imparting the whole microorganism a torque. Previous works investigated 'Ca. M. multicellularis' behavior when free swimming in water; however, they occur in sediments where bumping into solid particles must be routine. In this work, we investigate the swimming trajectories of 'Ca. M. multicellularis' close to solid boundaries using video microscopy. We applied magnetic fields 0.25-8.0 mT parallel to the optical axis of a light microscope, such that microorganisms were driven upwards towards a coverslip. Because their swimming trajectories approach cylindrical helixes, circular profiles would be expected. Nevertheless, at fields 0.25-1.1 mT, most trajectory projections were roughly sinusoidal, and net movements were approximately perpendicular to applied magnetic fields. Closed loops appeared in some trajectory projections at 1.1 mT, which could indicate a transition to the loopy profiles observed at magnetic fields ≥ 2.15 mT. The behavior of 'Ca. M. multicellularis' near natural magnetic grains showed that they were temporarily trapped by the particle's magnetic field but could reverse the direction of movement to flee away. Our results show that interactions of 'Ca. M. multicellularis with solid boundaries and magnetic grains are complex and possibly involve mechano-taxis.
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Affiliation(s)
- Carolina N Keim
- Instituto de Microbiologia Paulo de Góes, CCS, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, RJ, 21941-902, Brazil.
| | - Daniel Mendes da Silva
- Instituto de Microbiologia Paulo de Góes, CCS, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, RJ, 21941-902, Brazil
| | - Roger Duarte de Melo
- Centro Brasileiro de Pesquisas Físicas - CBPF, Rua Xavier Sigaud 150, Urca, Rio de Janeiro, RJ, 22290-180, Brazil
| | - Daniel Acosta-Avalos
- Centro Brasileiro de Pesquisas Físicas - CBPF, Rua Xavier Sigaud 150, Urca, Rio de Janeiro, RJ, 22290-180, Brazil
| | - Marcos Farina
- Instituto de Ciências Biomédicas, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Henrique Lins de Barros
- Centro Brasileiro de Pesquisas Físicas - CBPF, Rua Xavier Sigaud 150, Urca, Rio de Janeiro, RJ, 22290-180, Brazil
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7
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Busigny V, Mathon FP, Jézéquel D, Bidaud CC, Viollier E, Bardoux G, Bourrand JJ, Benzerara K, Duprat E, Menguy N, Monteil CL, Lefevre CT. Mass collection of magnetotactic bacteria from the permanently stratified ferruginous Lake Pavin, France. Environ Microbiol 2021; 24:721-736. [PMID: 33687779 DOI: 10.1111/1462-2920.15458] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 03/04/2021] [Accepted: 03/07/2021] [Indexed: 01/16/2023]
Abstract
Obtaining high biomass yields of specific microorganisms for culture-independent approaches is a challenge faced by scientists studying organism's recalcitrant to laboratory conditions and culture. This difficulty is highly decreased when studying magnetotactic bacteria (MTB) since their unique behaviour allows their enrichment and purification from other microorganisms present in aquatic environments. Here, we use Lake Pavin, a permanently stratified lake in the French Massif Central, as a natural laboratory to optimize collection and concentration of MTB that thrive in the water column and sediments. A method is presented to separate MTB from highly abundant abiotic magnetic particles in the sediment of this crater lake. For the water column, different sampling approaches are compared such as in situ collection using a Niskin bottle and online pumping. By monitoring several physicochemical parameters of the water column, we identify the ecological niche where MTB live. Then, by focusing our sampling at the peak of MTB abundance, we show that the online pumping system is the most efficient for fast recovering of large volumes of water at a high spatial resolution, which is necessary considering the sharp physicochemical gradients observed in the water column. Taking advantage of aerotactic and magnetic MTB properties, we present an efficient method for MTB concentration from large volumes of water. Our methodology represents a first step for further multidisciplinary investigations of the diversity, metagenomic and ecology of MTB populations in Lake Pavin and elsewhere, as well as chemical and isotopic analyses of their magnetosomes.
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Affiliation(s)
- Vincent Busigny
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, Paris, F-75005, France.,Institut Universitaire de France, Paris, 75005, France
| | - François P Mathon
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, Paris, F-75005, France.,Aix-Marseille University, CNRS, CEA, UMR7265 Institute of Biosciences and Biotechnologies of Aix-Marseille, CEA Cadarache, Saint-Paul-lez-Durance, F-13108, France
| | - Didier Jézéquel
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, Paris, F-75005, France.,INRAE & Université Savoie Mont Blanc, UMR CARRTEL, Thonon-les-Bains, 74200, France
| | - Cécile C Bidaud
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, IRD. Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), Paris, France
| | - Eric Viollier
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, Paris, F-75005, France
| | - Gérard Bardoux
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, Paris, F-75005, France
| | - Jean-Jacques Bourrand
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, Paris, F-75005, France
| | - Karim Benzerara
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, IRD. Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), Paris, France
| | - Elodie Duprat
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, IRD. Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), Paris, France
| | - Nicolas Menguy
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, IRD. Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), Paris, France
| | - Caroline L Monteil
- Aix-Marseille University, CNRS, CEA, UMR7265 Institute of Biosciences and Biotechnologies of Aix-Marseille, CEA Cadarache, Saint-Paul-lez-Durance, F-13108, France
| | - Christopher T Lefevre
- Aix-Marseille University, CNRS, CEA, UMR7265 Institute of Biosciences and Biotechnologies of Aix-Marseille, CEA Cadarache, Saint-Paul-lez-Durance, F-13108, France
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8
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Tan SM, Ismail MH, Cao B. Biodiversity of magnetotactic bacteria in the tropical marine environment of Singapore revealed by metagenomic analysis. ENVIRONMENTAL RESEARCH 2021; 194:110714. [PMID: 33422504 DOI: 10.1016/j.envres.2021.110714] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/22/2020] [Accepted: 01/01/2021] [Indexed: 06/12/2023]
Abstract
Most studies on the diversity of magnetotactic bacteria (MTB) have been conducted on samples obtained from the Northern or the Southern hemispheres. The diversity of MTB in tropical Asia near the geo-equator, with a close-to-zero geomagnetic inclination, weak magnetic field and constantly high seawater temperature has never been explored. This study aims to decipher the diversity of MTB in the marine environment of Singapore through shotgun metagenomics. Although MTB has been acknowledged to be ubiquitous in aquatic environments, we did not observe magnetotactic behaviour in the samples. However, we detected the presence and determined the diversity of MTB through bioinformatic analyses. Metagenomic analysis suggested majority of the MTB in the seafloor sediments represents novel MTB taxa that cannot be classified at the species level. The relative abundance of MTB (~0.2-1.69%) in the samples collected from the marine environment of Singapore was found to be substantially lower than studies for other regions. In contrast to other studies, the genera Magnetovibrio and Desulfamplus, but not Magnetococcus, were the dominant MTB. Additionally, we recovered 3 MTB genomic bins that are unclassified at the species level, with Magnetovibrio blakemorei being the closest-associated genome. All the recovered genomic bins contain homologs of at least 5 of the 7 mam genes but lack homologs for mamI, a membrane protein suggested to take part in the magenetosome invagination. This study fills in the knowledge gap of MTB biodiversity in the tropical marine environment near the geo-equator. Our findings will facilitate future research efforts aiming to unravel the ecological roles of MTB in the tropical marine environments as well as to bioprospecting novel MTB that have been adapted to tropical marine environments for biotechnological applications.
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Affiliation(s)
- Shi Ming Tan
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Drive, SBS-01N-27, 637551, Singapore
| | - Muhammad Hafiz Ismail
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Drive, SBS-01N-27, 637551, Singapore
| | - Bin Cao
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 60 Nanyang Drive, SBS-01N-27, 637551, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Ave, N1-01C-69, 639798, Singapore.
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9
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Pan H, Dong Y, Teng Z, Li J, Zhang W, Xiao T, Wu LF. A species of magnetotactic deltaproteobacterium was detected at the highest abundance during an algal bloom. FEMS Microbiol Lett 2019; 366:5681391. [PMID: 31855240 DOI: 10.1093/femsle/fnz253] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 12/18/2019] [Indexed: 11/13/2022] Open
Abstract
Magnetotactic bacteria (MTB) are a group of microorganisms that have the ability to synthesize intracellular magnetic crystals (magnetosomes). They prefer microaerobic or anaerobic aquatic sediments. Thus, there is growing interest in their ecological roles in various habitats. In this study we found co-occurrence of a large rod-shaped deltaproteobacterial magnetotactic bacterium (tentatively named LR-1) in the sediment of a brackish lagoon with algal bloom. Electron microscopy observations showed that they were ovoid to slightly curved rods having a mean length of 6.3 ± 1.1 μm and a mean width of 4.1 ± 0.4 μm. Each cell had a single polar flagellum. They contained hundreds of bullet-shaped intracellular magnetite magnetosomes. Phylogenetic analysis revealed that they were most closely related to Desulfamplus magnetovallimortis strain BW-1, and belonged to the Deltaproteobacteria. Our findings indicate that LR-1 may be a new species of MTB. We propose that deltaproteobacterial MTB may play an important role in iron cycling and so may represent a reservoir of iron, and be an indicator species for monitoring algal blooms in such eutrophic ecosystems. These observations provide new clues to the cultivation of magnetotactic Deltaproteobacteria and the control of algal blooms, although further studies are needed.
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Affiliation(s)
- Hongmiao Pan
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Qingdao, 266237, China.,Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.,International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, 7 Nanhai Road, Qingdao, 266071, China
| | - Yi Dong
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Qingdao, 266237, China.,Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.,International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, 7 Nanhai Road, Qingdao, 266071, China
| | - Zhaojie Teng
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China
| | - Jinhua Li
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Qingdao, 266237, China.,Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, 19 Beitucheng Western Road, Beijing, 100029, China.,International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, 7 Nanhai Road, Qingdao, 266071, China
| | - Wenyan Zhang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Qingdao, 266237, China.,Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.,International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, 7 Nanhai Road, Qingdao, 266071, China
| | - Tian Xiao
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Qingdao, 266237, China.,Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, China.,International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, 7 Nanhai Road, Qingdao, 266071, China
| | - Long-Fei Wu
- International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, 7 Nanhai Road, Qingdao, 266071, China.,LCB, Aix-Marseille Univ, CNRS, 31 Chemin Joseph Aiguier, Marseille, 13402, France
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10
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Amor M, Tharaud M, Gélabert A, Komeili A. Single-cell determination of iron content in magnetotactic bacteria: implications for the iron biogeochemical cycle. Environ Microbiol 2019; 22:823-831. [PMID: 31187921 DOI: 10.1111/1462-2920.14708] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 05/24/2019] [Accepted: 06/09/2019] [Indexed: 12/14/2022]
Abstract
Magnetotactic bacteria (MTB) are ubiquitous aquatic microorganisms that mineralize dissolved iron into intracellular magnetic crystals. After cell death, these crystals are trapped into sediments that remove iron from the soluble pool. MTB may significantly impact the iron biogeochemical cycle, especially in the ocean where dissolved iron limits nitrogen fixation and primary productivity. A thorough assessment of their impact has been hampered by a lack of methodology to measure the amount of, and variability in, their intracellular iron content. We quantified the iron mass contained in single MTB cells of Magnetospirillum magneticum strain AMB-1 using a time-resolved inductively coupled plasma-mass spectrometry methodology. Bacterial iron content depends on the external iron concentration, and reaches a maximum value of ~10-6 ng of iron per cell. From these results, we calculated the flux of dissolved iron incorporation into environmental MTB populations and conclude that MTB may mineralize a significant fraction of dissolved iron into crystals.
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Affiliation(s)
- Matthieu Amor
- Department of Plant and Microbial Biology, University of California, Berkeley, California, 94720-3102, USA
| | - Mickaël Tharaud
- Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Univ. Paris Diderot, UMR 7154 CNRS, 1 rue Jussieu, 75238 Paris, France
| | - Alexandre Gélabert
- Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Univ. Paris Diderot, UMR 7154 CNRS, 1 rue Jussieu, 75238 Paris, France
| | - Arash Komeili
- Department of Plant and Microbial Biology, University of California, Berkeley, California, 94720-3102, USA.,Department of Molecular and Cell Biology, University of California, Berkeley, California, 94720-3200, USA
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11
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Fan X, Ding S, Gong M, Chen M, Gao S, Jin Z, Tsang DCW. Different Influences of Bacterial Communities on Fe (III) Reduction and Phosphorus Availability in Sediments of the Cyanobacteria- and Macrophyte-Dominated Zones. Front Microbiol 2018; 9:2636. [PMID: 30487778 PMCID: PMC6247781 DOI: 10.3389/fmicb.2018.02636] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 10/16/2018] [Indexed: 12/05/2022] Open
Abstract
Little is known about the effects of bacterial community on iron (Fe) and phosphorus (P) cycles in sediments under different primary producer habitats in different seasons. Lake Taihu has both the cyanobacteria- and macrophyte-dominated lake zones. In this work, the abundance and structure of bacterial community was investigated using qPCR and 16S rRNA gene high throughput sequencing, respectively. Compared with the sediments in the cyanobacteria-dominated lake zone, sediments in the macrophyte-dominated lake zone had higher TP, TOC and TN contents but lower DO and Eh values. Dissolved reactive P, dissolved Fe, and their molar ratios (Fe/P) were lower in the sediments of the cyanobacteria-dominated lake zone than those in the macrophyte-dominated lake zone. Consistent with this was the significantly lower abundance of total and typical Fe redox transforming bacteria in the sediment of the cyanobacteria-dominated lake zone than those in the macrophyte-dominated lake zone. Correlation analyses also revealed positive influence of abundances of total bacteria and typical Fe reducing bacteria on dissolved Fe and Fe/P ratio. The results showed that, in the cyanobacteria-dominated open water zone, Acidimicrobiaceae was capable of Fe metabolism, contributing to higher P flux in summer. In the cyanobacteria-dominated bay, Sva0081 sediment group and Desulfobulbaceae could transform sulfate to sulfide, which resulted in the reduction of Fe (III), while in the macrophyte-dominated zones, Clostridium sensu stricto 1 could couple oxidation of organic carbon with the reduction of Fe (III). The present study adds new knowledge linking the bacterial communities with the physicochemical cycles of Fe and P in sediments under different primary producer habitats.
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Affiliation(s)
- Xianfang Fan
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - Shiming Ding
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - Mengdan Gong
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
- Graduate School of the Chinese Academy of Sciences, Beijing, China
| | - Musong Chen
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - ShuaiShuai Gao
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
- Graduate School of the Chinese Academy of Sciences, Beijing, China
| | - Zengfeng Jin
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
- Graduate School of the Chinese Academy of Sciences, Beijing, China
| | - Daniel C. W. Tsang
- Department of Civil and Environmental Engineering, Faculty of Construction and Environment, The Hong Kong Polytechnic University, Kowloon, China
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Liu J, Zhang W, Du H, Leng X, Li JH, Pan H, Xu J, Wu LF, Xiao T. Seasonal changes in the vertical distribution of two types of multicellular magnetotactic prokaryotes in the sediment of Lake Yuehu, China. ENVIRONMENTAL MICROBIOLOGY REPORTS 2018; 10:475-484. [PMID: 29687636 DOI: 10.1111/1758-2229.12652] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
There are two genetically distinct morphological types of multicellular magnetotactic prokaryotes (MMPs) in the intertidal zone of Lake Yuehu (China): ellipsoidal MMPs (eMMPs) and spherical MMPs (sMMPs). We studied the vertical distribution of both types of MMPs in the sediment at Lake Yuehu during 1 year. Both types of MMPs were observed at sediment depths ranging from 1 to 34 cm, depending on the seasons. The eMMPs distributed at depths of 2-34 cm during spring, 1-11 cm during summer, 2-21 cm during autumn and 9-32 cm during winter. The eMMP species Candidatus Magnetananas rongchenensis, with magnetite magnetosomes, dominated at all distribution depths. These results suggested that Ca. M. rongchenensis migrated vertically during four seasons. The vertical profiles of oxidation-reduction potential (ORP) in Lake Yuehu changed seasonally, and these changes coincided with the seasonal distribution of MMPs, suggesting that the ORP affected the vertical distribution of MMPs. In addition, high concentrations of ammonium and silicate were associated with low abundances of MMPs.
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Affiliation(s)
- Jia Liu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
- College of Earth Science, University of Chinese Academy of Sciences, Beijing 100864, China
| | - Wenyan Zhang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
- International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, Marseille, Beijing-Qingdao-Sanya
| | - Haijian Du
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Xiaoyun Leng
- College of Marine and Environmental Sciences, Tianjin University of Science and Technology, Tianjin 300457, PR China
| | - Jin-Hua Li
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
- International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, Marseille, Beijing-Qingdao-Sanya
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Hongmiao Pan
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
- International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, Marseille, Beijing-Qingdao-Sanya
| | - Jianhong Xu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology Chinese Academy of Sciences, Qingdao 266071, China
| | - Long-Fei Wu
- International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, Marseille, Beijing-Qingdao-Sanya
- Aix-Marseille Univ, CNRS, LCB, Marseille, 31 chemin Joseph Aiguier, F-13402, France
| | - Tian Xiao
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
- International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), CNRS-CAS, Marseille, Beijing-Qingdao-Sanya
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Perrin E, Bacci G, Garrelly L, Canganella F, Bianconi G, Fani R, Mengoni A. Furnishing spaceship environment: evaluation of bacterial biofilms on different materials used inside International Space Station. Res Microbiol 2018; 169:289-295. [PMID: 29751063 DOI: 10.1016/j.resmic.2018.04.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 03/22/2018] [Accepted: 04/22/2018] [Indexed: 12/26/2022]
Abstract
Performed inside International Space Station (ISS) from 2011 to 2016, VIABLE (eValuatIon And monitoring of microBiofiLms insidE International Space Station) ISS was a long-lasting experiment aimed at evaluating the bacterial contamination on different surface space materials subjected to different pre-treatment, to provide useful information for future space missions. In this work, surfaces samples of the VIABLE ISS experiment were analyzed to determine both the total bacterial load (ATP-metry, qPCR) and the composition of the microbial communities (16S rRNA genes amplicon sequencing). Data obtained showed a low bacterial contamination of all the surfaces, with values in agreement with those allowed inside ISS, and with a taxonomic composition similar to those found in previous studies (Enterobacteriales, Bacillales, Lactobacillales and Actinomycetales). No pre-treatment or material effect were observed on both the bacterial load and the composition of the communities, but for both a slight effect of the position (expose/not expose to air) was observed. In conclusion, under the conditions used for VIABLE ISS, no material or pre-treatment seems to be better than others in terms of quantity and type of bacterial contamination.
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Affiliation(s)
- Elena Perrin
- Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino (FI), I-50019, Italy.
| | - Giovanni Bacci
- Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino (FI), I-50019, Italy.
| | - Laurent Garrelly
- GLBiocontrol, 9, avenue de l'Europe, Cap Alpha, 34 830 Clapiers, France.
| | - Francesco Canganella
- Department of Biological, Agricultural and Forestry Sciences, Università della Tuscia, Via San Camillo de Lellis snc, I-01100 Viterbo Italy.
| | - Giovanna Bianconi
- Department of Biological, Agricultural and Forestry Sciences, Università della Tuscia, Via San Camillo de Lellis snc, I-01100 Viterbo Italy.
| | | | - Renato Fani
- Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino (FI), I-50019, Italy.
| | - Alessio Mengoni
- Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino (FI), I-50019, Italy.
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14
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Yan L, Xing W. Methods to Study Magnetotactic Bacteria and Magnetosomes. J Microbiol Methods 2018. [DOI: 10.1016/bs.mim.2018.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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15
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Bacterial community structure and novel species of magnetotactic bacteria in sediments from a seamount in the Mariana volcanic arc. Sci Rep 2017; 7:17964. [PMID: 29269894 PMCID: PMC5740136 DOI: 10.1038/s41598-017-17445-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 11/27/2017] [Indexed: 12/15/2022] Open
Abstract
Seamounts are undersea mountains rising abruptly from the sea floor and interacting dynamically with underwater currents. They represent unique biological habitats with various microbial community structures. Certain seamount bacteria form conspicuous extracellular iron oxide structures, including encrusted stalks, flattened bifurcating tubes, and filamentous sheaths. To extend our knowledge of seamount ecosystems, we performed an integrated study on population structure and the occurrence of magnetotactic bacteria (MTB) that synthesize intracellular iron oxide nanocrystals in sediments of a seamount in the Mariana volcanic arc. We found Proteobacteria dominant at 13 of 14 stations, but ranked second in abundance to members of the phylum Firmicutes at the deep-water station located on a steep slope facing the Mariana-Yap Trench. Live MTB dwell in biogenic sediments from all 14 stations ranging in depth from 238 to 2,023 m. Some magnetotactic cocci possess the most complex flagellar apparatus yet reported; 19 flagella are arranged in a 3:4:5:4:3 array within a flagellar bundle. Phylogenetic analysis of 16S rRNA gene sequences identified 16 novel species of MTB specific to this seamount. Together the results obtained indicate that geographic properties of the seamount stations are important in shaping the bacterial community structure and the MTB composition.
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16
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He K, Gilder SA, Orsi WD, Zhao X, Petersen N. Constant Flux of Spatial Niche Partitioning through High-Resolution Sampling of Magnetotactic Bacteria. Appl Environ Microbiol 2017; 83:e01382-17. [PMID: 28778897 PMCID: PMC5626982 DOI: 10.1128/aem.01382-17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 08/01/2017] [Indexed: 11/20/2022] Open
Abstract
Magnetotactic bacteria (MTB) swim along magnetic field lines in water. They are found in aquatic habitats throughout the world, yet knowledge of their spatial and temporal distribution remains limited. To help remedy this, we took MTB-bearing sediment from a natural pond, mixed the thoroughly homogenized sediment into two replicate aquaria, and then counted three dominant MTB morphotypes (coccus, spirillum, and rod-shaped MTB cells) at a high spatiotemporal sampling resolution: 36 discrete points in replicate aquaria were sampled every ∼30 days over 198 days. Population centers of the MTB coccus and MTB spirillum morphotypes moved in continual flux, yet they consistently inhabited separate locations, displaying significant anticorrelation. Rod-shaped MTB were initially concentrated toward the northern end of the aquaria, but at the end of the experiment, they were most densely populated toward the south. The finding that the total number of MTB cells increased over time during the experiment argues that population reorganization arose from relative changes in cell division and death and not from migration. The maximum net growth rates were 10, 3, and 1 doublings day-1 and average net growth rates were 0.24, 0.11, and 0.02 doublings day-1 for MTB cocci, MTB spirilla, and rod-shaped MTB, respectively; minimum growth rates for all three morphotypes were -0.03 doublings day-1 Our results suggest that MTB cocci and MTB spirilla occupy distinctly different niches: their horizontal positioning in sediment is anticorrelated and under constant flux.IMPORTANCE Little is known about the horizontal distribution of magnetotactic bacteria in sediment or how the distribution changes over time. We therefore measured three dominant magnetotactic bacterium morphotypes at 36 places in two replicate aquaria each month for 7 months. We found that the spatial positioning of population centers changed over time and that the two most abundant morphotypes (MTB cocci and MTB spirilla) occupied distinctly different niches in the aquaria. Maximum and average growth and death rates were quantified for each of the three morphotypes based on 72 sites that were measured six times. The findings provided novel insight into the differential behavior of noncultured magnetotactic bacteria.
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Affiliation(s)
- Kuang He
- Department of Earth and Environmental Sciences, Ludwig-Maximilians Universität, Munich, Germany
| | - Stuart A Gilder
- Department of Earth and Environmental Sciences, Ludwig-Maximilians Universität, Munich, Germany
| | - William D Orsi
- Department of Earth and Environmental Sciences, Ludwig-Maximilians Universität, Munich, Germany
- GeoBio-Center, Ludwig-Maximilians Universität, Munich, Germany
| | - Xiangyu Zhao
- National Institute of Polar Research, Tokyo, Japan
| | - Nikolai Petersen
- Department of Earth and Environmental Sciences, Ludwig-Maximilians Universität, Munich, Germany
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17
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Descamps ECT, Monteil CL, Menguy N, Ginet N, Pignol D, Bazylinski DA, Lefèvre CT. Desulfamplus magnetovallimortis gen. nov., sp. nov., a magnetotactic bacterium from a brackish desert spring able to biomineralize greigite and magnetite, that represents a novel lineage in the Desulfobacteraceae. Syst Appl Microbiol 2017. [PMID: 28622795 DOI: 10.1016/j.syapm.2017.05.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A magnetotactic bacterium, designated strain BW-1T, was isolated from a brackish spring in Death Valley National Park (California, USA) and cultivated in axenic culture. The Gram-negative cells of strain BW-1T are relatively large and rod-shaped and possess a single polar flagellum (monotrichous). This strain is the first magnetotactic bacterium isolated in axenic culture capable of producing greigite and/or magnetite nanocrystals aligned in one or more chains per cell. Strain BW-1T is an obligate anaerobe that grows chemoorganoheterotrophically while reducing sulfate as a terminal electron acceptor. Optimal growth occurred at pH 7.0 and 28°C with fumarate as electron donor and carbon source. Based on its genome sequence, the G+C content is 40.72mol %. Phylogenomic and phylogenetic analyses indicate that strain BW-1T belongs to the Desulfobacteraceae family within the Deltaproteobacteria class. Based on average amino acid identity, strain BW-1T can be considered as a novel species of a new genus, for which the name Desulfamplus magnetovallimortis is proposed. The type strain of D. magnetovallimortis is BW-1T (JCM 18010T-DSM 103535T).
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Affiliation(s)
- Elodie C T Descamps
- CNRS/CEA/Aix-Marseille Université, UMR7265 Institut de biosciences et biotechnologies, Laboratoire de Bioénergétique Cellulaire, 13108 Saint Paul lez Durance, France
| | - Caroline L Monteil
- CNRS/CEA/Aix-Marseille Université, UMR7265 Institut de biosciences et biotechnologies, Laboratoire de Bioénergétique Cellulaire, 13108 Saint Paul lez Durance, France
| | - Nicolas Menguy
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, UMR 7590 CNRS-UPMC-MNHN-Sorbonne Université, 4 place Jussieu, 75252 Paris Cedex 05, France
| | - Nicolas Ginet
- CNRS/CEA/Aix-Marseille Université, UMR7265 Institut de biosciences et biotechnologies, Laboratoire de Bioénergétique Cellulaire, 13108 Saint Paul lez Durance, France; CNRS/Aix-Marseille Université, UMR7283 Laboratoire de Chimie Bactérienne, 13009 Marseille, France
| | - David Pignol
- CNRS/CEA/Aix-Marseille Université, UMR7265 Institut de biosciences et biotechnologies, Laboratoire de Bioénergétique Cellulaire, 13108 Saint Paul lez Durance, France
| | - Dennis A Bazylinski
- School of Life Sciences, University of Nevada at Las Vegas, Las Vegas, NV 89154-4004, USA
| | - Christopher T Lefèvre
- CNRS/CEA/Aix-Marseille Université, UMR7265 Institut de biosciences et biotechnologies, Laboratoire de Bioénergétique Cellulaire, 13108 Saint Paul lez Durance, France.
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Abstract
Magnetotactic bacteria derive their magnetic orientation from magnetosomes, which are unique organelles that contain nanometre-sized crystals of magnetic iron minerals. Although these organelles have evident potential for exciting biotechnological applications, a lack of genetically tractable magnetotactic bacteria had hampered the development of such tools; however, in the past decade, genetic studies using two model Magnetospirillum species have revealed much about the mechanisms of magnetosome biogenesis. In this Review, we highlight these new insights and place the molecular mechanisms of magnetosome biogenesis in the context of the complex cell biology of Magnetospirillum spp. Furthermore, we discuss the diverse properties of magnetosome biogenesis in other species of magnetotactic bacteria and consider the value of genetically 'magnetizing' non-magnetotactic bacteria. Finally, we discuss future prospects for this highly interdisciplinary and rapidly advancing field.
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19
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Fan X, Xing P. Differences in the Composition of Archaeal Communities in Sediments from Contrasting Zones of Lake Taihu. Front Microbiol 2016; 7:1510. [PMID: 27708641 PMCID: PMC5030832 DOI: 10.3389/fmicb.2016.01510] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 09/09/2016] [Indexed: 11/13/2022] Open
Abstract
In shallow lakes, different primary producers might impact the physiochemical characteristics of the sediment and the associated microbial communities. Until now, little was known about the features of sediment Archaea and their variation across different primary producer-dominated ecosystems. Lake Taihu provides a suitable study area with cyanobacteria- and macrophyte-dominated zones co-occurring in one ecosystem. The composition of the sediment archaeal community was assessed using 16S rRNA gene amplicon sequencing technology, based on which the potential variation with respect to the physiochemical characteristics of the sediment was analyzed. Euryarchaeota (30.19% of total archaeal sequences) and Bathyarchaeota (28.00%) were the two most abundant phyla, followed by Crenarchaeota (11.37%), Aigarchaeota (10.24%) and Thaumarchaeota (5.98%). The differences found in the composition of the archaeal communities between the two zones was significant (p = 0.005). Sediment from macrophyte-dominated zones had high TOC and TN content and an abundance of archaeal lineages potentially involved in the degradation of complex organic compounds, such as the order Thermoplasmatales. In the area dominated by Cyanobacteria, archaeal lineages related to sulfur metabolism, for example, Sulfolobales and Desulfurococcales, were significantly enriched. Among Bathyarchaeota, subgroups MCG-6 and MCG-15 were significantly accumulated in the sediment of areas dominated by macrophytes whereas MCG-4 was consistently dominant in both type of sediments. The present study contributes to the knowledge of sediment archaeal communities with different primary producers and their possible biogeochemical functions in sediment habitats.
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Affiliation(s)
- Xianfang Fan
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology (CAS)Nanjing, China; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science (CAS)Nanjing, China
| | - Peng Xing
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology (CAS) Nanjing, China
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20
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Revathy T, Jacob JJ, Jayasri MA, Suthindhiran K. Isolation and characterization of Magnetospirillum from saline lagoon. World J Microbiol Biotechnol 2016; 32:109. [PMID: 27263004 DOI: 10.1007/s11274-016-2075-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/24/2016] [Indexed: 10/21/2022]
Abstract
Magnetotactic bacteria (MTB) are aquatic prokaryotes that orient themselves to earth's magnetic field with the help of intracellular organelle magnetosomes. Although many species of MTB have been identified, the isolation of MTB is a challenging task due to the lack of systematic isolation procedure and/or commercial media. In this study, we are reporting the isolation of magnetotactic spirillum from the Pulicat lagoon, India using a systematic and selective procedure. Sampling site was chosen on the basis of physicochemical properties of the ecosystem and the catalysed reporter deposition fluorescence in situ hybridization (CARD-FISH) analysis of sediment samples. In the current study, a combination of techniques including 'capillary racetrack' Purification and gradient cultivation resulted in the isolation of magnetotactic spirilla from aquatic sediments. Based on the 16S rRNA gene sequence analysis, the strain was identified as Magnetospirillum and was designated as Magnetospirillum sp. VITRJS1. The genes responsible for magnetosome formation (mamA, B, E, F, K, M, O, P, Q, T) were successfully detected using PCR amplification. The presence of cbbM gene confirmed that the isolate is chemolithoautotroph and utilises reduced sulphur as an electron source. Furthermore, magnetosomes extracted from VITRJS1 found to be cubo-octahedral in shape and 45 nm in size. Our results indicate that the systematic procedure using sediment analysis, CARD-FISH, and a combination of isolation methods enables the selective and rapid isolation of MTB from aquatic sediment sample.
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Affiliation(s)
- T Revathy
- Marine Biotechnology and Bioproducts Lab, School of Biosciences and Technology, VIT University, Vellore, 632014, Tamilnadu, India
| | - Jobin John Jacob
- Marine Biotechnology and Bioproducts Lab, School of Biosciences and Technology, VIT University, Vellore, 632014, Tamilnadu, India
| | - M A Jayasri
- Marine Biotechnology and Bioproducts Lab, School of Biosciences and Technology, VIT University, Vellore, 632014, Tamilnadu, India
| | - K Suthindhiran
- Marine Biotechnology and Bioproducts Lab, School of Biosciences and Technology, VIT University, Vellore, 632014, Tamilnadu, India.
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Alsaiari SK, Ezzedine AH, Abdallah AM, Sougrat R, Khashab NM. Magnetotactic bacterial cages as safe and smart gene delivery vehicles. OPENNANO 2016. [DOI: 10.1016/j.onano.2016.07.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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Du HJ, Chen YR, Zhang R, Pan HM, Zhang WY, Zhou K, Wu LF, Xiao T. Temporal distributions and environmental adaptations of two types of multicellular magnetotactic prokaryote in the sediments of Lake Yuehu, China. ENVIRONMENTAL MICROBIOLOGY REPORTS 2015; 7:538-546. [PMID: 25727488 DOI: 10.1111/1758-2229.12284] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Accepted: 02/22/2015] [Indexed: 06/04/2023]
Abstract
Two morphotypes (spherical and ellipsoidal) of multicellular magnetotactic prokaryotes (MMPs) have been reported from the sediments of Lake Yuehu, China. Here, their temporal distributions and their relationships with biogeochemical parameters are studied. Samples were collected at approximately 2-week intervals from two sites (A and B) during the period September 2012 to December 2013. The abundance of MMPs was high in summer and autumn, but low in winter and spring. Furthermore, the peaks in the numbers of the two types of MMPs were sequential, with the highest concentration of the spherical MMPs occurring prior to that of the ellipsoidal MMPs. This may be related to different optimal growth temperatures for the two types. Although the two types of MMP coexisted at both sites, their numbers were different; at most times, spherical MMPs dominated at site A, whereas ellipsoidal MMPs dominated at site B. Geochemical analysis revealed that the environmental conditions at site A varied more than at site B. Compared with the widely distributed spherical MMPs, ellipsoidal MMPs seemed to prefer more stable habitats. This is the first report of the temporal distribution of ellipsoidal MMPs in sediments, suggesting that their environmental adaptations differ from those of spherical MMPs.
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Affiliation(s)
- Hai-Jian Du
- Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
- College of Earth Science, University of Chinese Academy of Sciences, Beijing, 100864, China
| | - Yi-Ran Chen
- Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
- CNRS, Laboratoire International Associé de la Bio-Minéralisation et Nano-Structures (LIA-BioMNSL), Marseille, F-13402, France
| | - Rui Zhang
- Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
- College of Earth Science, University of Chinese Academy of Sciences, Beijing, 100864, China
| | - Hong-Miao Pan
- Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
- CNRS, Laboratoire International Associé de la Bio-Minéralisation et Nano-Structures (LIA-BioMNSL), Marseille, F-13402, France
| | - Wen-Yan Zhang
- Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
- CNRS, Laboratoire International Associé de la Bio-Minéralisation et Nano-Structures (LIA-BioMNSL), Marseille, F-13402, France
| | - Ke Zhou
- College of Resources and Environment, Qingdao Agriculture University, Qingdao, 266109, China
| | - Long-Fei Wu
- CNRS, Laboratoire International Associé de la Bio-Minéralisation et Nano-Structures (LIA-BioMNSL), Marseille, F-13402, France
- CNRS, LCB UMR 7257, Institut de Microbiologie de la Méditerranée, Aix Marseille Université, Marseille, F-13402, France
| | - Tian Xiao
- Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
- CNRS, Laboratoire International Associé de la Bio-Minéralisation et Nano-Structures (LIA-BioMNSL), Marseille, F-13402, France
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Sorty AM, Shaikh NR. Novel co-enrichment method for isolation of magnetotactic bacteria. J Basic Microbiol 2014; 55:520-6. [PMID: 25546328 DOI: 10.1002/jobm.201400457] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 11/09/2014] [Indexed: 11/09/2022]
Abstract
A novel co-enrichment technique was designed for enrichment of magnetotactic bacteria from soil, water, and sediments. Delayed addition of iron uptake inducer and the iron source proved amenable to induce magnetosome synthesis by MTB followed by their separation from consortium using magnetic flux. We successfully enriched and isolated both North seeking as well as South seeking magnetotactic bacteria from Lonar Lake (Buldhana), Moti Lake (Jalna), Ghanewadi Lake (Jalna), Ganesh Lake (Miraj), Rankala Lake (Kolhapur), and industrial metal-contaminated glaying soils (Jalna) and a soil (Karad), (MS, India) exposed to high-voltage electric current. The hanging drop preparations and growth under magnetic stress on low-agar media allowed conformation of magnetotactic behavior of the isolates. Both Gram positive and Gram negative MTB were isolated with diverse morphologies. South seeking population was more predominant. The soil inhabitants showed little dwelling property which was more prominent in case of aquatic inhabitants. The use of in situ pH and salt concentrations during enrichment and isolation found suited. The simultaneous growth of whole consortium in the system ensured the in situ simulation of microenvironment needful for proper growth of fastidious MTB.
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Affiliation(s)
- Ajay M Sorty
- PG Department of Microbiology, Yashwantrao Chavan College of Science, Karad (MS), India
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24
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Fuduche M, Postec A, Davidson S, Chauvin JP, Galès G, Hirschler-Réa A, Ollivier B, Wu LF, Pradel N. Diversity of Magnetotactic Bacteria from a French Pristine Mediterranean Area. Curr Microbiol 2014; 70:499-505. [DOI: 10.1007/s00284-014-0745-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 10/27/2014] [Indexed: 10/24/2022]
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Sudden motility reversal indicates sensing of magnetic field gradients in Magnetospirillum magneticum AMB-1 strain. ISME JOURNAL 2014; 9:1399-409. [PMID: 25478682 DOI: 10.1038/ismej.2014.224] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 09/14/2014] [Accepted: 10/23/2014] [Indexed: 11/08/2022]
Abstract
Many motile unicellular organisms have evolved specialized behaviors for detecting and responding to environmental cues such as chemical gradients (chemotaxis) and oxygen gradients (aerotaxis). Magnetotaxis is found in magnetotactic bacteria and it is defined as the passive alignment of these cells to the geomagnetic field along with active swimming. Herein we show that Magnetospirillum magneticum (AMB-1) show a unique set of responses that indicates they sense and respond not only to the direction of magnetic fields by aligning and swimming, but also to changes in the magnetic field or magnetic field gradients. We present data showing that AMB-1 cells exhibit sudden motility reversals when we impose them to local magnetic field gradients. Our system employs permalloy (Ni(80)Fe(20)) islands to curve and diverge the magnetic field lines emanating from our custom-designed Helmholtz coils in the vicinity of the islands (creating a drop in the field across the islands). The three distinct movements we have observed as they approach the permalloy islands are: unidirectional, single reverse and double reverse. Our findings indicate that these reverse movements occur in response to magnetic field gradients. In addition, using a permanent magnet we found further evidence that supports this claim. Motile AMB-1 cells swim away from the north and south poles of a permanent magnet when the magnet is positioned less than ∼30 mm from the droplet of cells. All together, these results indicate previously unknown response capabilities arising from the magnetic sensing systems of AMB-1 cells. These responses could enable them to cope with magnetic disturbances that could in turn potentially inhibit their efficient search for nutrients.
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26
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Joshi KB. Microbes: mini iron factories. Indian J Microbiol 2014; 54:483-5. [PMID: 25320452 DOI: 10.1007/s12088-014-0497-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 09/06/2014] [Indexed: 11/26/2022] Open
Abstract
Microbes have flourished in extreme habitats since beginning of the Earth and have played an important role in geological processes like weathering, mineralization, diagenesis, mineral formation and destruction. Biotic mineralization is one of the most fascinating examples of how microbes have been influencing geological processes. Iron oxidizing and reducing bacteria are capable of precipitating wide varieties of iron oxides (magnetite), carbonates (siderite) and sulphides (greigite) via controlled or induced mineralization processes. Microbes have also been considered to play an important role in the history of evolution of sedimentary rocks on Earth from the formation of banded iron formations during the Archean to modern biotic bog iron and ochre deposits. Here, we discuss the role that microbes have been playing in precipitation of iron and the role and importance of interdisciplinary studies in the field of geology and biology in solving some of the major geological mysteries.
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Taoka A, Kondo J, Oestreicher Z, Fukumori Y. Characterization of uncultured giant rod-shaped magnetotactic Gammaproteobacteria from a freshwater pond in Kanazawa, Japan. Microbiology (Reading) 2014; 160:2226-2234. [DOI: 10.1099/mic.0.078717-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Magnetotactic bacteria (MTB) are widespread aquatic bacteria, and are a phylogenetically, physiologically and morphologically heterogeneous group, but they all have the ability to orientate and move along the geomagnetic field using intracellular magnetic organelles called magnetosomes. Isolation and cultivation of novel MTB are necessary for a comprehensive understanding of magnetosome formation and function in divergent MTB. In this study, we enriched a giant rod-shaped magnetotactic bacterium (strain GRS-1) from a freshwater pond in Kanazawa, Japan. Cells of strain GRS-1 were unusually large (~13×~8 µm). They swam in a helical trajectory towards the south pole of a bar magnet by means of a polar bundle of flagella. Another striking feature of GRS-1 was the presence of two distinct intracellular biomineralized structures: large electron-dense granules composed of calcium and long chains of magnetosomes that surround the large calcium granules. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that this strain belongs to the Gammaproteobacteria and represents a new genus of MTB.
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Affiliation(s)
- Azuma Taoka
- Bio-AFM Frontier Research Center, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Japan
- School of Natural System, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Japan
| | - Junya Kondo
- Department of Life Science, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, Japan
| | - Zachery Oestreicher
- School of Natural System, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Japan
| | - Yoshihiro Fukumori
- Bio-AFM Frontier Research Center, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Japan
- School of Natural System, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Japan
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Kolinko S, Richter M, Glöckner FO, Brachmann A, Schüler D. Single-cell genomics reveals potential for magnetite and greigite biomineralization in an uncultivated multicellular magnetotactic prokaryote. ENVIRONMENTAL MICROBIOLOGY REPORTS 2014; 6:524-531. [PMID: 25079475 DOI: 10.1111/1758-2229.12198] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 07/25/2014] [Indexed: 06/03/2023]
Abstract
For magnetic orientation, magnetotactic bacteria biosynthesize magnetosomes, which consist of membrane-enveloped magnetic nanocrystals of either magnetite (Fe3 O4 ) or greigite (Fe3 S4 ). While magnetite formation is increasingly well understood, much less is known about the genetic control of greigite biomineralization. Recently, two related yet distinct sets of magnetosome genes were discovered in a cultivated magnetotactic deltaproteobacterium capable of synthesizing either magnetite or greigite, or both minerals. This led to the conclusion that greigite and magnetite magnetosomes are synthesized by separate biomineralization pathways. Although magnetosomes of both mineral types co-occurred in uncultured multicellular magnetotactic prokaryotes (MMPs), so far only one type of magnetosome genes could be identified in the available genome data. The MMP Candidatus Magnetomorum strain HK-1 from coastal tidal sand flats of the North Sea (Germany) was analysed by a targeted single-cell approach. The draft genome assembly resulted in a size of 14.3 Mb and an estimated completeness of 95%. In addition to genomic features consistent with a sulfate-reducing lifestyle, we identified numerous genes putatively involved in magnetosome biosynthesis. Remarkably, most mam orthologues were present in two paralogous copies with highest similarity to either magnetite or greigite type magnetosome genes, supporting the ability to synthesize magnetite and greigite magnetosomes.
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Affiliation(s)
- Sebastian Kolinko
- Ludwig-Maximilians-Universität Munich, Microbiology, Großhaderner Str. 2-4, 82152, Planegg-Martinsried, Germany
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29
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Magnetic properties of uncultivated magnetotactic bacteria and their contribution to a stratified estuary iron cycle. Nat Commun 2014; 5:4797. [DOI: 10.1038/ncomms5797] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 07/25/2014] [Indexed: 11/08/2022] Open
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Chen YR, Zhang R, Du HJ, Pan HM, Zhang WY, Zhou K, Li JH, Xiao T, Wu LF. A novel species of ellipsoidal multicellular magnetotactic prokaryotes from Lake Yuehu in China. Environ Microbiol 2014; 17:637-47. [PMID: 24725306 DOI: 10.1111/1462-2920.12480] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 04/04/2014] [Indexed: 11/26/2022]
Abstract
Two morphotypes of multicellular magnetotactic prokaryotes (MMPs) have been identified: spherical (several species) and ellipsoidal (previously one species). Here, we report novel ellipsoidal MMPs that are ∼ 10 × 8 μm in size, and composed of about 86 cells arranged in six to eight interlaced circles. Each MMP was composed of cells that synthesized either bullet-shaped magnetite magnetosomes alone, or both bullet-shaped magnetite and rectangular greigite magnetosomes. They showed north-seeking magnetotaxis, ping-pong motility and negative phototaxis at a velocity up to 300 μm s(-1) . During reproduction, they divided along either their long- or short-body axes. For genetic analysis, we sorted the ellipsoidal MMPs with micromanipulation and amplified their genomes using multiple displacement amplification. We sequenced the 16S rRNA gene and found 6.9% sequence divergence from that of ellipsoidal MMPs, Candidatus Magnetananas tsingtaoensis and > 8.3% divergence from those of spherical MMPs. Therefore, the novel MMPs belong to different species and genus compared with the currently known ellipsoidal and spherical MMPs respectively. The novel MMPs display a morphological cell differentiation, implying a potential division of labour. These findings provide new insights into the diversity of MMPs in general, and contribute to our understanding of the evolution of multicellularity among prokaryotes.
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Affiliation(s)
- Yi-Ran Chen
- Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; University of Chinese Academy of Sciences, Beijing, China
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31
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Abstract
Magnetotactic bacteria (MTB) are widespread, motile, diverse prokaryotes that biomineralize a unique organelle called the magnetosome. Magnetosomes consist of a nano-sized crystal of a magnetic iron mineral that is enveloped by a lipid bilayer membrane. In cells of almost all MTB, magnetosomes are organized as a well-ordered chain. The magnetosome chain causes the cell to behave like a motile, miniature compass needle where the cell aligns and swims parallel to magnetic field lines. MTB are found in almost all types of aquatic environments, where they can account for an important part of the bacterial biomass. The genes responsible for magnetosome biomineralization are organized as clusters in the genomes of MTB, in some as a magnetosome genomic island. The functions of a number of magnetosome genes and their associated proteins in magnetosome synthesis and construction of the magnetosome chain have now been elucidated. The origin of magnetotaxis appears to be monophyletic; that is, it developed in a common ancestor to all MTB, although horizontal gene transfer of magnetosome genes also appears to play a role in their distribution. The purpose of this review, based on recent progress in this field, is focused on the diversity and the ecology of the MTB and also the evolution and transfer of the molecular determinants involved in magnetosome formation.
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32
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Bacci G, Pagoto E, Passaponti M, Vannocci P, Ugolini A, Mengoni A. Composition of supralittoral sediments bacterial communities in a Mediterranean island. ANN MICROBIOL 2014. [DOI: 10.1007/s13213-014-0829-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Lin W, Bazylinski DA, Xiao T, Wu LF, Pan Y. Life with compass: diversity and biogeography of magnetotactic bacteria. Environ Microbiol 2013; 16:2646-58. [PMID: 24148107 DOI: 10.1111/1462-2920.12313] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 10/12/2013] [Indexed: 11/29/2022]
Abstract
Magnetotactic bacteria (MTB) are unique in their ability to synthesize intracellular nano-sized minerals of magnetite and/or greigite magnetosomes for magnetic orientation. Thus, they provide an excellent model system to investigate mechanisms of biomineralization. MTB play important roles in bulk sedimentary magnetism and have numerous versatile applications in paleoenvironmental reconstructions, and biotechnological and biomedical fields. Significant progress has been made in recent years in describing the composition of MTB communities and distribution through innovative cultivation-dependent and -independent techniques. In this review, the most recent contributions to the field of diversity and biogeography of MTB are summarized and reviewed. Emphasis is on the novel insights into various factors/processes potentially affecting MTB community distribution. An understanding of the present-day biogeography of MTB, and the ruling parameters of their spatial distribution, will eventually help us predict MTB community shifts with environmental changes and assess their roles in global iron cycling.
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Affiliation(s)
- Wei Lin
- Biogeomagnetism Group, Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth's Deep Interior, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China; France-China Bio-Mineralization and Nano-Structures Laboratory, Chinese Academy of Sciences, Beijing, 100029, China
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Zhou K, Zhang WY, Pan HM, Li JH, Yue HD, Xiao T, Wu LF. Adaptation of spherical multicellular magnetotactic prokaryotes to the geochemically variable habitat of an intertidal zone. Environ Microbiol 2013; 15:1595-605. [DOI: 10.1111/1462-2920.12057] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 11/05/2012] [Accepted: 11/22/2012] [Indexed: 11/29/2022]
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35
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Lin W, Wang Y, Pan Y. Short-term effects of temperature on the abundance and diversity of magnetotactic cocci. Microbiologyopen 2012; 1:53-63. [PMID: 22950012 PMCID: PMC3426400 DOI: 10.1002/mbo3.7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 12/06/2011] [Accepted: 12/11/2011] [Indexed: 02/01/2023] Open
Abstract
Temperature is one of the most important climate factors that can regulate the activity and growth of organisms. However, it is so far unclear how temperature influences the abundance and community composition of magnetotactic bacteria (MTB) that mineralize intracellular magnetite and/or greigite magnetosomes and play significant roles in the global iron cycling and sediment magnetization. To address this specific problem, in this study we have assessed the impact of temperature on freshwater magnetotactic cocci through laboratory microcosm simulations. Microcosms containing MTB were exposed to four constant temperatures ranging from 9°C to 37°C. After 10 days and 28 days of incubation, no significant differences in abundance were detected in microcosms at 9°C, 15°C, and 26°C (Student's t-test, P > 0.05); however, microcosms exposed to 37°C exhibited a significant decrease of magnetotactic cocci abundance (P < 0.05). Dendrogram analysis of community-amplified ribosomal DNA restriction analysis (community ARDRA) banding patterns distinguished the 37°C samples from samples at lower temperatures regardless of incubation periods. Furthermore, clone library analysis revealed that most of the operational taxonomic units (OTUs) detected in samples from 9°C to 26°C were absent from the 37°C microcosms, whereas six OTUs were exclusively detected in the 37°C samples. Community compositions from four incubation temperatures were further compared using statistical phylogenetic methods (UniFrac and LIBSHUFF), which revealed that the 37°C samples harbored phylogenetically distinct MTB communities compared to those found in 9°C, 15°C, and 26°C samples. Taken together, our results indicate that elevated temperature can influence the abundance and diversity of dominant members of magnetotactic cocci. This linkage further infers that the abundance and diversity of MTB (e.g., based on the fossil magnetosomes) may be useful in reconstruction of paleotemperature.
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Affiliation(s)
- Wei Lin
- Biogeomagnetism Group, Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth's Deep Interior, Institute of Geology and Geophysics, Chinese Academy of SciencesBeijing 100029, China
- France-China Bio-Mineralization and Nano-Structures Laboratory, Institute of Geology and Geophysics, Chinese Academy of SciencesBeijing 100029, China
| | - Yinzhao Wang
- Biogeomagnetism Group, Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth's Deep Interior, Institute of Geology and Geophysics, Chinese Academy of SciencesBeijing 100029, China
- France-China Bio-Mineralization and Nano-Structures Laboratory, Institute of Geology and Geophysics, Chinese Academy of SciencesBeijing 100029, China
| | - Yongxin Pan
- Biogeomagnetism Group, Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth's Deep Interior, Institute of Geology and Geophysics, Chinese Academy of SciencesBeijing 100029, China
- France-China Bio-Mineralization and Nano-Structures Laboratory, Institute of Geology and Geophysics, Chinese Academy of SciencesBeijing 100029, China
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36
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Komeili A. Molecular mechanisms of compartmentalization and biomineralization in magnetotactic bacteria. FEMS Microbiol Rev 2012; 36:232-55. [PMID: 22092030 DOI: 10.1111/j.1574-6976.2011.00315.x] [Citation(s) in RCA: 158] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Magnetotactic bacteria (MB) are remarkable organisms with the ability to exploit the earth's magnetic field for navigational purposes. To do this, they build specialized compartments called magnetosomes that consist of a lipid membrane and a crystalline magnetic mineral. These organisms have the potential to serve as models for the study of compartmentalization as well as biomineralization in bacteria. Additionally, they offer the opportunity to design applications that take advantage of the particular properties of magnetosomes. In recent years, a sustained effort to identify the molecular basis of this process has resulted in a clearer understanding of the magnetosome formation and biomineralization. Here, I present an overview of MB and explore the possible molecular mechanisms of membrane remodeling, protein sorting, cytoskeletal organization, iron transport, and biomineralization that lead to the formation of a functional magnetosome organelle.
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Affiliation(s)
- Arash Komeili
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.
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37
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Postec A, Tapia N, Bernadac A, Joseph M, Davidson S, Wu LF, Ollivier B, Pradel N. Magnetotactic bacteria in microcosms originating from the French Mediterranean Coast subjected to oil industry activities. MICROBIAL ECOLOGY 2012; 63:1-11. [PMID: 21766218 DOI: 10.1007/s00248-011-9910-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 06/30/2011] [Indexed: 05/31/2023]
Abstract
Magnetotactic bacteria (MTB) mineralize nanosized magnetite or greigite crystals within cells and thus play an important role in the biogeochemical process. Despite decades of research, knowledge of MTB distribution and ecology, notably in areas subjected to oil industry activities, is still limited. In the present study, we investigated the presence of MTB in the Gulf of Fos, French Mediterranean coast, which is subjected to intensive oil industry activities. Microcosms containing sediments/water (1:2, v/v) from several sampling sites were monitored over several weeks. The presence of MTB was revealed in five of eight sites. Diverse and numerous MTB were revealed particularly from one site (named CAR), whilst temporal variations of a homogenous magnetotactic cocci population was shown within the LAV site microcosm over a 4-month period. Phylogenetic analysis revealed that they belonged to Alphaproteobacteria, and a novel genus from the LAV site was evidenced. Among the physicochemical parameters measured, a correlation was shown between the variation of MTB abundance in microcosms and the redox state of sulphur compounds.
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Affiliation(s)
- Anne Postec
- IRD, UMR_D 180, Université Aix Marseille, ESIL case 925, 163 Avenue de Luminy, 13288, Marseille Cedex 9, France
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38
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Müller WEG, Binder M, von Lintig J, Guo YW, Wang X, Kaandorp JA, Wiens M, Schröder HC. Interaction of the retinoic acid signaling pathway with spicule formation in the marine sponge Suberites domuncula through activation of bone morphogenetic protein-1. Biochim Biophys Acta Gen Subj 2011; 1810:1178-94. [PMID: 21952113 DOI: 10.1016/j.bbagen.2011.09.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2011] [Revised: 09/05/2011] [Accepted: 09/08/2011] [Indexed: 10/17/2022]
Abstract
BACKGROUND The formation of the spicules in siliceous sponges involves the formation of cylinder-like structures in the extraspicular space, composed of the enzyme silicatein and the calcium-dependent lectin. SCOPE OF REVIEW Molecular cloning of the cDNAs (carotene dioxygenase, retinal dehydrogenase, and BMB-1 [bone morphogenic protein-1]) from the demosponge Suberites domuncula was performed. These tools were used to understand the retinoid metabolism in the animal by qRT-PCR, immunoblotting and TEM. MAJOR CONCLUSIONS We demonstrate that silintaphin-2, a silicatein-interacting protein, is processed from a longer-sized 15-kDa precursor to a truncated, shorter-sized 13kDa calcium-binding protein via proteolytic cleavage at the dipeptide Ala↓Asp, mediated by BMP-1. The expression of this protease as well as the expression of two key enzymes of the carotinoid metabolism, the β,β-carotene-15,15'-dioxygenase and the retinal dehydrogenase/reductase, were found to be strongly up-regulated by retinoic acid. Hence retinoic acid turned out to be a key factor in skeletogenesis in the most ancient still existing metazoans, the sponges. GENERAL SIGNIFICANCE It is shown that retinoic acid regulates the formation of the organic cylinder that surrounds the axis of the spicules and enables, as a scaffold, the radial apposition of new silica layers and hence the growth of the spicules.
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Affiliation(s)
- Werner E G Müller
- ERC Advanced Grant Research Group, Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Germany.
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Shapiro OH, Hatzenpichler R, Buckley DH, Zinder SH, Orphan VJ. Multicellular photo-magnetotactic bacteria. ENVIRONMENTAL MICROBIOLOGY REPORTS 2011; 3:233-238. [PMID: 23761255 DOI: 10.1111/j.1758-2229.2010.00215.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Multicellular magnetotactic bacteria (MMB) are unique microorganisms typically comprised of 10-40 bacterial cells arranged around a central acellular compartment. Their life cycle has no known unicellular stage and division occurs by separation of a single MMB aggregate into two identical offspring. In this study, South-seeking multicellular magnetotactic bacteria (ssMMB) were enriched from a New England salt marsh. When exposed to light, ssMMB reversed their magnetotactic behaviour to become North-seeking. The exposure time needed to generate the reversal response varied with light wavelength and intensity. Extensive exposure to light appeared to be lethal. This is the first report of a Northern hemisphere MMB displaying South-seeking behaviour and the first time a MMB is found to exhibit photo-magnetotaxis. We suggest that this mechanism enables ssMMB to optimize their location with regard to chemical gradients and light intensities, and propose a model to explain the peculiar balance between photo- and magnetotaxis.
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Affiliation(s)
- Orr H Shapiro
- Microbial Diversity Course, Marine Biological Laboratory, Woods Hole, MA 02543, USA Department of Biotechnology Engineering, Ben-Gurion University of the Negev, Be'er-Sheva 84105, Israel Department of Microbial Ecology, University of Vienna, Vienna, A-1090, AustriaDepartments of Crop and Soil Sciences Microbiology, Cornell University, Ithaca, NY 14853, USA Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
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Bacterial community and "Candidatus Accumulibacter" population dynamics in laboratory-scale enhanced biological phosphorus removal reactors. Appl Environ Microbiol 2010; 76:5479-87. [PMID: 20601516 DOI: 10.1128/aem.00370-10] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
"Candidatus Accumulibacter" and total bacterial community dynamics were studied in two lab-scale enhanced biological phosphorus removal (EBPR) reactors by using a community fingerprint technique, automated ribosomal intergenic spacer analysis (ARISA). We first evaluated the quantitative capability of ARISA compared to quantitative real-time PCR (qPCR). ARISA and qPCR provided comparable relative quantification of the two dominant "Ca. Accumulibacter" clades (IA and IIA) detected in our reactors. The quantification of total "Ca. Accumulibacter" 16S rRNA genes relative to that from the total bacterial community was highly correlated, with ARISA systematically underestimating "Ca. Accumulibacter" abundance, probably due to the different normalization techniques applied. During 6 months of normal (undisturbed) operation, the distribution of the two clades within the total "Ca. Accumulibacter" population was quite stable in one reactor while comparatively dynamic in the other reactor. However, the variance in the clade distribution did not appear to affect reactor performance. Instead, good EBPR activity was positively associated with the abundance of total "Ca. Accumulibacter." Therefore, we concluded that the different clades in the system provided functional redundancy. We disturbed the reactor operation by adding nitrate together with acetate feeding in the anaerobic phase to reach initial reactor concentrations of 10 mg/liter NO(3)-N for 35 days. The reactor performance deteriorated with a concomitant decrease in the total "Ca. Accumulibacter" population, suggesting that a population shift was the cause of performance upset after a long exposure to nitrate in the anaerobic phase.
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Preparation of genomic DNA from a single species of uncultured magnetotactic bacterium by multiple-displacement amplification. Appl Environ Microbiol 2010; 76:1480-5. [PMID: 20081000 DOI: 10.1128/aem.02124-09] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Magnetotactic bacteria comprise a phylogenetically diverse group that is capable of synthesizing intracellular magnetic particles. Although various morphotypes of magnetotactic bacteria have been observed in the environment, bacterial strains available in pure culture are currently limited to a few genera due to difficulties in their enrichment and cultivation. In order to obtain genetic information from uncultured magnetotactic bacteria, a genome preparation method that involves magnetic separation of cells, flow cytometry, and multiple displacement amplification (MDA) using phi29 polymerase was used in this study. The conditions for the MDA reaction using samples containing 1 to 100 cells were evaluated using a pure-culture magnetotactic bacterium, "Magnetospirillum magneticum AMB-1," whose complete genome sequence is available. Uniform gene amplification was confirmed by quantitative PCR (Q-PCR) when 100 cells were used as a template. This method was then applied for genome preparation of uncultured magnetotactic bacteria from complex bacterial communities in an aquatic environment. A sample containing 100 cells of the uncultured magnetotactic coccus was prepared by magnetic cell separation and flow cytometry and used as an MDA template. 16S rRNA sequence analysis of the MDA product from these 100 cells revealed that the amplified genomic DNA was from a single species of magnetotactic bacterium that was phylogenetically affiliated with magnetotactic cocci in the Alphaproteobacteria. The combined use of magnetic separation, flow cytometry, and MDA provides a new strategy to access individual genetic information from magnetotactic bacteria in environmental samples.
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Lin W, Li J, Schüler D, Jogler C, Pan Y. Diversity analysis of magnetotactic bacteria in Lake Miyun, northern China, by restriction fragment length polymorphism. Syst Appl Microbiol 2009; 32:342-50. [DOI: 10.1016/j.syapm.2008.10.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Accepted: 10/05/2008] [Indexed: 10/21/2022]
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Geelhoed JS, Sorokin DY, Epping E, Tourova TP, Banciu HL, Muyzer G, Stams AJM, van Loosdrecht MCM. Microbial sulfide oxidation in the oxic-anoxic transition zone of freshwater sediment: involvement of lithoautotrophic Magnetospirillum strain J10. FEMS Microbiol Ecol 2009; 70:54-65. [PMID: 19659746 DOI: 10.1111/j.1574-6941.2009.00739.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The oxic-anoxic transition zone (OATZ) of freshwater sediments, where opposing gradients exist of reduced iron and sulfide with oxygen, creates a suitable environment for microorganisms that derive energy from the oxidation of iron or sulfide. Gradient microcosms incubated with freshwater sediment showed rapid microbial turnover of sulfide and oxygen compared with sterile systems. Microcosms with FeS as a substrate also showed growth at the OATZ and subsequent dilution series resulted in the isolation of three novel strains, of which strain J10 grows chemolithoautotrophically with reduced sulfur compounds under microaerobic conditions. All three strains are motile spirilla with bipolar flagella, related to the genera Magnetospirillum and Dechlorospirillum within the Alphaproteobacteria. Strain J10 is closely related to Magnetospirillum gryphiswaldense and is the first strain in this genus found to be capable of autotrophic growth. Thiosulfate was oxidized completely to sulfate, with a yield of 4 g protein mol(-1) thiosulfate, and autotrophic growth was evidenced by incorporation of (13)C derived from bicarbonate into biomass. A putative gene encoding ribulose 1,5-bisphosphate carboxylase/oxygenase type II was identified in strain J10, suggesting that the Calvin-Benson-Bassham cycle is used for autotrophic growth. Analogous genes are also present in other magnetospirilla, and in the autotrophically growing alphaproteobacterium magnetic vibrio MV-1.
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Affiliation(s)
- Jeanine S Geelhoed
- Department of Biotechnology, Environmental Biotechnology, Delft University of Technology, Delft, The Netherlands.
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Affiliation(s)
- Damien Faivre
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
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Abstract
Thanks to the work of Terrance J. Beveridge and other pioneers in the field of metal-microbe interactions, prokaryotes are well known to sequester metals and other ions intracellularly in various forms. These forms range from poorly ordered deposits of metals to well-ordered mineral crystals. Studies on well-ordered crystalline structures have generally focused on intracellular organelles produced by magnetotactic bacteria that are ubiquitous in terrestrial and marine environments that precipitate Fe(3)O(4) or Fe(3)S(4), Fe-bearing minerals that have magnetic properties and are enclosed in intracellular membranes. In contrast, studies on less-well ordered minerals have focused on Fe-, As-, Mn-, Au-, Se- and Cd-precipitates that occur intracellularly. The biological and environmental function of these particles remains a matter of debate.
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Affiliation(s)
- K J Edwards
- Geomicrobiology Group, Department of Biological Sciences, University of Southern California, 3616 Trousdale Parkway, Los Angeles, CA 90089-0371, USA.
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