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Li J, Guo YK, Zhao QX, He JZ, Zhang Q, Cao HY, Liang CQ. Microbial cell wall sorption and Fe-Mn binding in rhizosphere contribute to the obstruction of cadmium from soil to rice. Front Microbiol 2023; 14:1162119. [PMID: 37138638 PMCID: PMC10149983 DOI: 10.3389/fmicb.2023.1162119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 03/07/2023] [Indexed: 05/05/2023] Open
Abstract
Screening high-tolerant microorganisms to cadmium (Cd) and revealing their bio-obstruction mechanism could be significant for Cd regulation from farmland to the food chain. We examined the tolerance and bio-removal efficiency of Cd ions of two bacterial strains, Pseudomonas putida 23483 and Bacillus sp. GY16, and measured the accumulation of Cd ions in rice tissues and its different chemical forms in soil. The results showed that the two strains had high tolerance to Cd, but the removal efficiency was decreased successively with increasing Cd concentrations (0.05 to 5 mg kg-1). Cell-sorption accounted for the major proportion of Cd removal compared with excreta binding in both strains, which was conformed to the pseudo-second-order kinetics. At the subcellular level, Cd was mostly taken up by the cell mantle and cell wall, and only a small amount entered into the cytomembrane and cytoplasmic with time progressed (0 to 24 h) in each concentration. The cell mantle and cell wall sorption decreased with increasing Cd concentration, especially in the cytomembrane and cytoplasmic. The scanning electron microscope (SEM) and energy dispersive X-ray (EDS) analysis verified that Cd ions were attached to the cell surface, and the functional groups of C-H, C-N, C=O, N-H, and O-H in the cell surface may participate in cell-sorption process tested by the FTIR analysis. Furthermore, inoculation of the two strains significantly decreased Cd accumulation in rice straw and grain but increased in the root, increased Cd enrichment ratio in root from soil, decreased Cd translocation ratio from root to straw and grain, and increased the Cd concentrations of Fe-Mn binding form and residual form in rhizosphere soil. This study highlights that the two strains mainly removed Cd ions in solution through biosorption and passivated soil Cd as Fe-Mn combined form ascribe to its characteristics of manganese-oxidizing, eventually achieving bio-obstruction of Cd from soil to rice grain.
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Affiliation(s)
- Jie Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yi-Kai Guo
- Ecological Environment Planning and Environmental Protection Technology Center of Qinghai Province, Xining, China
| | - Qing-Xia Zhao
- Institute of New Rural Development, Guizhou University, Guiyang, China
| | - Ji-Zheng He
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Qian Zhang
- Key Laboratory of Land Surface Pattern and Simulation, Beijing Key Laboratory of Environmental Damage Assessment and Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Hong-Ying Cao
- Key Laboratory of Land Surface Pattern and Simulation, Beijing Key Laboratory of Environmental Damage Assessment and Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- *Correspondence: Hong-Ying Cao
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The “Infernaccio” Gorges: Microbial Diversity of Black Deposits and Isolation of Manganese-Solubilizing Bacteria. BIOLOGY 2022; 11:biology11081204. [PMID: 36009831 PMCID: PMC9404752 DOI: 10.3390/biology11081204] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/02/2022] [Accepted: 08/10/2022] [Indexed: 11/17/2022]
Abstract
Simple Summary “Infernaccio” gorges are one of the Earth’s hidden habitats in Central Italy. Beyond the deep incisions and high slopes, these gorges are characterized by black deposits in gorge walls and covering rock surfaces. Several geological events have shaped these unique geological formations and their microbiota. This study investigated microbial contribution to black deposit formation and isolating Mn-oxide-solubilizing bacteria. Our results provided evidence of the putative role of Bacteria and Archaea in forming manganese oxide deposits. Findings also showed that these deposits are a source of valuable strains with manganese oxide bioleaching properties, essential for bioremediation and metal recovery. Abstract The present study explored the microbial diversity of black deposits found in the “Infernaccio” gorge. X-ray Powdered Diffraction (XRPD) was used to investigate the crystallinity of the samples and to identify the minerals. Scanning electron microscope and energy-dispersive X-ray spectroscopy (SEM-EDS) were used to detect the bacterial imprints, analyze microbe–mineral interactions, and highlight the chemical element distribution in the black deposits. 16S rRNA gene metabarcoding allowed the study of Archaea and Bacteria communities. Mn-oxide-solubilizing isolates were also obtained and characterized by culturable and molecular approaches. The multidisciplinary approach showed the occurrence of deposits composed of birnessite, diopside, halloysite, and leucite. Numerous bacterial imprints confirmed the role of microorganisms in forming these deposits. The Bacteria and Archaea communities associated with these deposits and runoff waters are dynamic and shaped by seasonal changes. The uncultured and unknown taxa are the most common and abundant. These amplicon sequence variants (ASVs) were mainly assigned to Proteobacteria and Bacteroidetes phyla. Six isolates showed interesting Mn solubilization abilities under microaerophilic conditions. Molecular characterization associated isolates to Brevibacterium, Bacillus, Neobacillus, and Rhodococcus genera. The findings enriched our knowledge of geomicrobiological aspects of one of the Earth’s hidden habitats. The study also unveiled the potential of this environment as an isolation source of biotechnologically relevant bacteria.
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Mineralogical and Genomic Constraints on the Origin of Microbial Mn Oxide Formation in Complexed Microbial Community at the Terrestrial Hot Spring. Life (Basel) 2022; 12:life12060816. [PMID: 35743847 PMCID: PMC9224936 DOI: 10.3390/life12060816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/18/2022] [Accepted: 05/26/2022] [Indexed: 11/17/2022] Open
Abstract
Manganese (Mn) oxides are widespread on the surface environments of the modern Earth. The role of microbial activities in the formation of Mn oxides has been discussed for several decades. However, the mechanisms of microbial Mn oxidation, and its role in complex microbial communities in natural environments, remain uncertain. Here, we report the geochemical, mineralogical, and metagenomic evidence for biogenic Mn oxides, found in Japanese hot spring sinters. The low crystallinity of Mn oxides, and their spatial associations with organic matter, support the biogenic origin of Mn oxides. Specific multicopper oxidases (MCOs), which are considered Mn-oxidizing enzymes, were identified using metagenomic analyses. Nanoscale nuggets of copper sulfides were, also, discovered in the organic matter in Mn-rich sinters. A part of these copper sulfides most likely represents traces of MCOs, and this is the first report of traces of Mn-oxidizing enzyme in geological samples. Metagenomic analyses, surprisingly, indicated a close association of Mn oxides, not only in aerobic but also in anaerobic microbial communities. These new findings offer the unique and unified positions of Mn oxides, with roles that have not been ignored, to sustain anaerobic microbial communities in hot spring environments.
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Sjöberg S, Stairs CW, Allard B, Homa F, Martin T, Sjöberg V, Ettema TJG, Dupraz C. Microbiomes in a manganese oxide producing ecosystem in the Ytterby mine, Sweden: impact on metal mobility. FEMS Microbiol Ecol 2020; 96:fiaa169. [PMID: 32815988 PMCID: PMC7593233 DOI: 10.1093/femsec/fiaa169] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 08/13/2020] [Indexed: 12/28/2022] Open
Abstract
Microbe-mediated precipitation of Mn-oxides enriched in rare earth elements (REE) and other trace elements was discovered in tunnels leading to the main shaft of the Ytterby mine, Sweden. Defining the spatial distribution of microorganisms and elements in this ecosystem provide a better understanding of specific niches and parameters driving the emergence of these communities and associated mineral precipitates. Along with elemental analyses, high-throughput sequencing of the following four subsystems were conducted: (i) water seeping from a rock fracture into the tunnel, (ii) Mn-oxides and associated biofilm; referred to as the Ytterby Black Substance (YBS) biofilm (iii) biofilm forming bubbles on the Mn-oxides; referred to as the bubble biofilm and (iv) fracture water that has passed through the biofilms. Each subsystem hosts a specific collection of microorganisms. Differentially abundant bacteria in the YBS biofilm were identified within the Rhizobiales (e.g. Pedomicrobium), PLTA13 Gammaproteobacteria, Pirellulaceae, Hyphomonadaceae, Blastocatellia and Nitrospira. These taxa, likely driving the Mn-oxide production, were not detected in the fracture water. This biofilm binds Mn, REE and other trace elements in an efficient, dynamic process, as indicated by substantial depletion of these metals from the fracture water as it passes through the Mn deposit zone. Microbe-mediated oxidation of Mn(II) and formation of Mn(III/IV)-oxides can thus have considerable local environmental impact by removing metals from aquatic environments.
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Affiliation(s)
- Susanne Sjöberg
- Department of Geological Sciences, Stockholm University, Svante Arrhenius väg 8, SE-106 91 Stockholm, Sweden
| | - Courtney W Stairs
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, SE-751 23 Uppsala, Sweden
| | - Bert Allard
- Man-Technology-Environment Research Centre (MTM), Örebro University, SE-701 82 Örebro, Sweden
| | - Felix Homa
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, SE-751 23 Uppsala, Sweden
- Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, Stippeneng 4, 6708WE Wageningen, The Netherlands
| | - Tom Martin
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, SE-751 23 Uppsala, Sweden
| | - Viktor Sjöberg
- Man-Technology-Environment Research Centre (MTM), Örebro University, SE-701 82 Örebro, Sweden
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, SE-751 23 Uppsala, Sweden
- Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, Stippeneng 4, 6708WE Wageningen, The Netherlands
| | - Christophe Dupraz
- Department of Geological Sciences, Stockholm University, Svante Arrhenius väg 8, SE-106 91 Stockholm, Sweden
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Thomas PJ, Boller AJ, Satagopan S, Tabita FR, Cavanaugh CM, Scott KM. Isotope discrimination by form IC RubisCO from
Ralstonia eutropha
and
Rhodobacter sphaeroides
, metabolically versatile members of ‘
Proteobacteria
’ from aquatic and soil habitats. Environ Microbiol 2018; 21:72-80. [DOI: 10.1111/1462-2920.14423] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 09/18/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Phaedra J. Thomas
- Department of Integrative Biology University of South Florida Tampa FL USA
| | - Amanda J. Boller
- Department of Integrative Biology University of South Florida Tampa FL USA
| | - Sriram Satagopan
- Department of Microbiology The Ohio State University Columbus OH USA
| | - F. Robert Tabita
- Department of Microbiology The Ohio State University Columbus OH USA
| | - Colleen M. Cavanaugh
- Department of Organismic and Evolutionary Biology Harvard University Cambridge MA USA
| | - Kathleen M. Scott
- Department of Integrative Biology University of South Florida Tampa FL USA
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The Role of Bacterial Spores in Metal Cycling and Their Potential Application in Metal Contaminant Bioremediation. Microbiol Spectr 2016; 4. [DOI: 10.1128/microbiolspec.tbs-0018-2013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
ABSTRACT
Bacteria are one of the premier biological forces that, in combination with chemical and physical forces, drive metal availability in the environment. Bacterial spores, when found in the environment, are often considered to be dormant and metabolically inactive, in a resting state waiting for favorable conditions for them to germinate. However, this is a highly oversimplified view of spores in the environment. The surface of bacterial spores represents a potential site for chemical reactions to occur. Additionally, proteins in the outer layers (spore coats or exosporium) may also have more specific catalytic activity. As a consequence, bacterial spores can play a role in geochemical processes and may indeed find uses in various biotechnological applications. The aim of this review is to introduce the role of bacteria and bacterial spores in biogeochemical cycles and their potential use as toxic metal bioremediation agents.
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7
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DeLorenzo S, Bräuer SL, Edgmont CA, Herfort L, Tebo BM, Zuber P. Ubiquitous dissolved inorganic carbon assimilation by marine bacteria in the Pacific Northwest coastal ocean as determined by stable isotope probing. PLoS One 2012; 7:e46695. [PMID: 23056406 PMCID: PMC3463544 DOI: 10.1371/journal.pone.0046695] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2012] [Accepted: 09/06/2012] [Indexed: 11/25/2022] Open
Abstract
In order to identify bacteria that assimilate dissolved inorganic carbon (DIC) in the northeast Pacific Ocean, stable isotope probing (SIP) experiments were conducted on water collected from 3 different sites off the Oregon and Washington coasts in May 2010, and one site off the Oregon Coast in September 2008 and March 2009. Samples were incubated in the dark with 2 mM (13)C-NaHCO(3), doubling the average concentration of DIC typically found in the ocean. Our results revealed a surprising diversity of marine bacteria actively assimilating DIC in the dark within the Pacific Northwest coastal waters, indicating that DIC fixation is relevant for the metabolism of different marine bacterial lineages, including putatively heterotrophic taxa. Furthermore, dark DIC-assimilating assemblages were widespread among diverse bacterial classes. Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes dominated the active DIC-assimilating communities across the samples. Actinobacteria, Betaproteobacteria, Deltaproteobacteria, Planctomycetes, and Verrucomicrobia were also implicated in DIC assimilation. Alteromonadales and Oceanospirillales contributed significantly to the DIC-assimilating Gammaproteobacteria within May 2010 clone libraries. 16S rRNA gene sequences related to the sulfur-oxidizing symbionts Arctic96BD-19 were observed in all active DIC assimilating clone libraries. Among the Alphaproteobacteria, clones related to the ubiquitous SAR11 clade were found actively assimilating DIC in all samples. Although not a dominant contributor to our active clone libraries, Betaproteobacteria, when identified, were predominantly comprised of Burkholderia. DIC-assimilating bacteria among Deltaproteobacteria included members of the SAR324 cluster. Our research suggests that DIC assimilation is ubiquitous among many bacterial groups in the coastal waters of the Pacific Northwest marine environment and may represent a significant metabolic process.
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Affiliation(s)
- Suzanne DeLorenzo
- Center for Coastal Margin Observation & Prediction and Division of Environmental & Biomolecular Systems, Oregon Health & Science University, Beaverton, Oregon, United States of America.
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8
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Anderson CR, Davis RE, Bandolin NS, Baptista AM, Tebo BM. Analysis of in situ manganese(II) oxidation in the Columbia River and offshore plume: linking Aurantimonas and the associated microbial community to an active biogeochemical cycle. Environ Microbiol 2011; 13:1561-76. [PMID: 21418498 DOI: 10.1111/j.1462-2920.2011.02462.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Columbia River is a major source of dissolved nutrients and trace metals for the west coast of North America. A large proportion of these nutrients are sourced from the Columbia River Estuary, where coastal and terrestrial waters mix and resuspend particulate matter within the water column. As estuarine water is discharged off the coast, it transports the particulate matter, dissolved nutrients and microorganisms forming nutrient-rich and metabolically dynamic plumes. In this study, bacterial manganese oxidation within the plume and estuary was investigated during spring and neap tides. The microbial community proteome was fractionated and assayed for Mn oxidation activity. Proteins from the outer membrane and the loosely bound outer membrane fractions were separated using size exclusion chromatography and Mn(II)-oxidizing eluates were analysed with tandem mass spectrometry to identify potential Mn oxidase protein targets. Multi-copper oxidase (MCO) and haem-peroxidase enzymes were identified in active fractions. T-RFLP profiles and cluster analysis indicates that organisms and bacterial communities capable of oxidizing Mn(II) can be sourced from the Columbia River estuary and nearshore coastal ocean. These organisms are producing up to 10 fM MnO₂ cell⁻¹ day⁻¹. Evidence for the presence of Mn(II)-oxidizing bacterial isolates from the genera Aurantimonas, Rhodobacter, Bacillus and Shewanella was found in T-RFLP profiles. Specific Q-PCR probes were designed to target potential homologues of the Aurantimonas manganese oxidizing peroxidase (Mop). By comparing total Mop homologues, Aurantimonas SSU rRNA and total bacterial SSU rRNA gene copies, it appears that Aurantimonas can only account for ~1.7% of the peroxidase genes quantified. Under the broad assumption that at least some of the peroxidase homologues quantified are involved in manganese oxidation, it is possible that other organisms oxidize manganese via peroxidases.
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Affiliation(s)
- C R Anderson
- Division of Environmental and Biomolecular Systems, Oregon Health & Science University, Beaverton, OR 97006, USA.
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9
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Manganese Oxidation by Bacteria: Biogeochemical Aspects. MOLECULAR BIOMINERALIZATION 2011; 52:49-76. [DOI: 10.1007/978-3-642-21230-7_3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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10
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Meng YT, Zheng YM, Zhang LM, He JZ. Biogenic Mn oxides for effective adsorption of Cd from aquatic environment. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2009; 157:2577-2583. [PMID: 19345460 DOI: 10.1016/j.envpol.2009.02.035] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2008] [Revised: 02/22/2009] [Accepted: 02/25/2009] [Indexed: 05/27/2023]
Abstract
Biogenic Mn oxides exert important controls on trace metal cycling in aquatic and soil environments. A Mn-oxidizing bacterium Bacillus sp. WH4 was isolated from Fe-Mn nodules of an agrudalf in central China. The biogenic Mn oxides formed by mediation of this Mn oxidizing microorganism were identified as short-ranged and nano-sized Mn oxides. Cd adsorption isotherms, pH effect on adsorption and kinetics were investigated in comparison with an abiotic Mn oxide todorokite. Maximum adsorption of Cd to the biogenic Mn oxides and todorokite was 2.04 and 0.69 mmol g(-1) sorbent, respectively. Thus, the biogenic Mn oxides were more effective Cd adsorbents than the abiotic Mn oxide in the aquatic environment. The findings could improve our knowledge of biogenic Mn oxides formation in the environment and their important roles in the biogeochemical cycles of heavy metals.
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Affiliation(s)
- You-Ting Meng
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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11
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Anderson CR, Dick GJ, Chu ML, Cho JC, Davis RE, Bräuer SL, Tebo BM. Aurantimonas manganoxydans, sp. nov. and Aurantimonas litoralis, sp. nov.: Mn(II) oxidizing representatives of a globally distributed clade of alpha-Proteobacteria from the order Rhizobiales. GEOMICROBIOLOGY JOURNAL 2009; 26:189-198. [PMID: 19768133 PMCID: PMC2746641 DOI: 10.1080/01490450902724840] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Several closely related Mn(II)-oxidizing alpha-Proteobacteria were isolated from very different marine environments: strain SI85-9A1 from the oxic/anoxic interface of a stratified Canadian fjord, strain HTCC 2156 from the surface waters off the Oregon coast, and strain AE01 from the dorsal surface of a hydrothermal vent tubeworm. 16S rRNA analysis reveals that these isolates are part of a tight phylogenetic cluster with previously characterized members of the genus Aurantimonas. Other organisms within this clade have been isolated from disparate environments such as surface waters of the Arctic and Mediterranean seas, a deep-sea hydrothermal plume, and a Caribbean coral. Further analysis of all these strains revealed that many of them are capable of oxidizing dissolved Mn(II) and producing particulate Mn(III/IV) oxides. Strains SI85-9A1 and HTCC 2156 were characterized further. Despite sharing nearly identical 16S rRNA gene sequences with the previously described Aurantimonas coralicida, whole genome DNA-DNA hybridization indicated that their overall genomic similarity is low. Polyphasic phenotype characterization further supported distinguishing characteristics among these bacteria. Thus SI85-9A1 and HTCC 2156 are described as two new species within the family 'Aurantimionadaceae': Aurantimonas manganoxydans sp. nov. and Aurantimonas litoralis sp. nov. This clade of bacteria is widely distributed around the globe and may be important contributors to Mn cycling in many environments. Our results highlight the difficulty in utilizing 16S rRNA-based approaches to investigate the microbial ecology of Mn(II) oxidation.
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Affiliation(s)
- C. R. Anderson
- Division of Environmental and Biomolecular Systems, Oregon Health and Science University, 20000 NW Walker Road, Beaverton, OR, 97006, USA, Telephone: 503 748 1992, Fax: 503 748 1464
| | - G. J. Dick
- Dept of Geological Sciences, University of Michigan, 2534 CC Little Bldg, 1100 North University Ave, Ann Arbor, MI 48109-1005
| | - M-L. Chu
- Division of Environmental and Biomolecular Systems, Oregon Health and Science University, 20000 NW Walker Road, Beaverton, OR, 97006, USA, Telephone: 503 748 1992, Fax: 503 748 1464
| | - J-C. Cho
- Department of Ocean Sciences, Division of Biology and Ocean Sciences, Inha University, Incheon 402-751, Republic of Korea
| | - R. E. Davis
- Division of Environmental and Biomolecular Systems, Oregon Health and Science University, 20000 NW Walker Road, Beaverton, OR, 97006, USA, Telephone: 503 748 1992, Fax: 503 748 1464
| | - S. L. Bräuer
- Rankin Science South, Appalachian State University, 572 Rivers Street, Boone, NC 28608-2027
| | - B. M. Tebo
- Division of Environmental and Biomolecular Systems, Oregon Health and Science University, 20000 NW Walker Road, Beaverton, OR, 97006, USA, Telephone: 503 748 1992, Fax: 503 748 1464
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Dick GJ, Podell S, Johnson HA, Rivera-Espinoza Y, Bernier-Latmani R, McCarthy JK, Torpey JW, Clement BG, Gaasterland T, Tebo BM. Genomic insights into Mn(II) oxidation by the marine alphaproteobacterium Aurantimonas sp. strain SI85-9A1. Appl Environ Microbiol 2008; 74:2646-58. [PMID: 18344346 PMCID: PMC2394881 DOI: 10.1128/aem.01656-07] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Accepted: 03/02/2008] [Indexed: 01/06/2023] Open
Abstract
Microbial Mn(II) oxidation has important biogeochemical consequences in marine, freshwater, and terrestrial environments, but many aspects of the physiology and biochemistry of this process remain obscure. Here, we report genomic insights into Mn(II) oxidation by the marine alphaproteobacterium Aurantimonas sp. strain SI85-9A1, isolated from the oxic/anoxic interface of a stratified fjord. The SI85-9A1 genome harbors the genetic potential for metabolic versatility, with genes for organoheterotrophy, methylotrophy, oxidation of sulfur and carbon monoxide, the ability to grow over a wide range of O(2) concentrations (including microaerobic conditions), and the complete Calvin cycle for carbon fixation. Although no growth could be detected under autotrophic conditions with Mn(II) as the sole electron donor, cultures of SI85-9A1 grown on glycerol are dramatically stimulated by addition of Mn(II), suggesting an energetic benefit from Mn(II) oxidation. A putative Mn(II) oxidase is encoded by duplicated multicopper oxidase genes that have a complex evolutionary history including multiple gene duplication, loss, and ancient horizontal transfer events. The Mn(II) oxidase was most abundant in the extracellular fraction, where it cooccurs with a putative hemolysin-type Ca(2+)-binding peroxidase. Regulatory elements governing the cellular response to Fe and Mn concentration were identified, and 39 targets of these regulators were detected. The putative Mn(II) oxidase genes were not among the predicted targets, indicating that regulation of Mn(II) oxidation is controlled by other factors yet to be identified. Overall, our results provide novel insights into the physiology and biochemistry of Mn(II) oxidation and reveal a genome specialized for life at the oxic/anoxic interface.
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Affiliation(s)
- Gregory J Dick
- Department of Environmental and Biomolecular Systems, OGI School of Science & Engineering, Oregon Health & Sciences University, 20000 NW Walker Rd., Beaverton, OR 97006, USA
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Nigro LM, King GM. Disparate distributions of chemolithotrophs containing form IA or IC large subunit genes for ribulose-1,5-bisphosphate carboxylase/oxygenase in intertidal marine and littoral lake sediments. FEMS Microbiol Ecol 2007; 60:113-25. [PMID: 17381527 DOI: 10.1111/j.1574-6941.2007.00272.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The distributions of bacterial form IA and form IC ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) were investigated using Lowes Cove intertidal mudflat and Damariscotta Lake littoral sediments by PCR amplification of 492-495 bp fragments of the large subunit RuBisCO gene, cbbL. Genomic extracts for amplification were obtained from lake surface (upper 2 mm), mudflat surface (upper 2 mm), subsurface (5-7 cm), and soft-shell clam (Mya arenaria) burrow-wall sediments, as well as from a sulfide-oxidizing mat. Phylogenetic analyses of cbbL clone libraries revealed that Lowes Cove sediments were dominated by form IA cbbL-containing sequences most closely related to cbbL genes of sulfur-oxidizing bacteria or sulfide-oxidizing mats. In contrast, Damariscotta Lake cbbL clones contained primarily form IC cbbL sequences, which typify aerobic CO- and hydrogen-oxidizing facultative chemolithotrophs. Statistical analyses supported clear differentiation of intertidal and lake chemolithotroph communities, and provided evidence for some differentiation among intertidal communities. amova and libshuff analyses of Lowes Cove libraries suggested that M. arenaria burrow-wall sediments did not harbour distinct communities compared with surface and subsurface sediments, but that surface and subsurface libraries displayed moderate differences. The results collectively support a conceptual model in which the relative distribution of form IA- and IC-containing bacterial chemolithotrophs depends on sulfide availability, which could reflect the role of sulfate reduction in sediment organic matter metabolism, or the presence of geothermal sulfide sources.
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Affiliation(s)
- Lisa M Nigro
- University of Maine, 193 Clarks Cove Road, Walpole, ME 04573, USA
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Denner EBM, Smith GW, Busse HJ, Schumann P, Narzt T, Polson SW, Lubitz W, Richardson LL. Aurantimonas coralicida gen. nov., sp. nov., the causative agent of white plague type II on Caribbean scleractinian corals. Int J Syst Evol Microbiol 2003; 53:1115-1122. [PMID: 12892136 DOI: 10.1099/ijs.0.02359-0] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A bacterium previously isolated from a diseased colony of the scleractinian coral Dichocoenia stokesi (common name elliptical star coral) was subjected to a detailed polyphasic taxonomic characterization. The isolate, designated WP1T, was halophilic and strictly aerobic and formed golden-orange-pigmented colonies after prolonged incubation. Cells of WP1T were gram-negative, rod-shaped and showed a characteristic branching rod morphology. Chemotaxonomically, WP1T was characterized by having Q-10 as the major respiratory lipoquinone and sym-homospermidine as the main component of the cellular polyamine content. The predominant constituent in the cellular fatty acid profile was C18:1 omega7c, along with C19:0 cyclo omega8c and C16:0. Other fatty acids present in smaller amounts were C17:0, C18:0, C16:1 omega7c, C20:1 omega7c and C18:1 2-OH. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. Minor amounts of diphosphatidylglycerol, phosphatidylmonomethylethanolamine and phosphatidyldimethylethanolamine were present. The G + C content of the genomic DNA was 66.3 mol%. Phylogenetic analysis of the 16S rRNA gene sequence showed that WP1T represents a separate subline of descent within the order 'Rhizobiales' of the 'Alphaproteobacteria'. The new line of descent falls within the group of families that includes the Rhizobiaceae, Bartonellaceae, Brucellaceae and 'Phyllobacteriaceae', with no particular relative within this group. The 16S rRNA gene sequence similarity to all established taxa within this group was not higher than 92.0% (to Mesorhizobium mediterraneum). To accommodate this emerging coral pathogen, the creation of a new genus and species is proposed, Aurantimonas coralicida gen. nov., sp. nov. (type strain WP1T = CIP 107386T = DSM 14790T).
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Affiliation(s)
- Ewald B M Denner
- Institut für Mikrobiologie und Genetik, Universität Wien, A-1030 Vienna, Austria
| | - Garriet W Smith
- Department of Biology and Geology, University of South Carolina Aiken, Aiken, SC, USA
| | - Hans-Jürgen Busse
- Institut für Bakteriologie, Mykologie und Hygiene, Veterinärmedizinische Universität, A-1210 Vienna, Austria
- Institut für Mikrobiologie und Genetik, Universität Wien, A-1030 Vienna, Austria
| | - Peter Schumann
- DSMZ - Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Braunschweig, Germany
| | - Thomas Narzt
- Institut für Zoologie, Abteilung Ultrastrukturforschung, Universität Wien, A-1090 Wien, Austria
| | - Shawn W Polson
- Department of Microbiology and Molecular Medicine, Clemson University, Clemson, SC 29634, USA
| | - Werner Lubitz
- Institut für Mikrobiologie und Genetik, Universität Wien, A-1030 Vienna, Austria
| | - Laurie L Richardson
- Department of Biological Sciences, Florida International University, Miami, FL 33199, USA
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15
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Francis CA, Co EM, Tebo BM. Enzymatic manganese(II) oxidation by a marine alpha-proteobacterium. Appl Environ Microbiol 2001; 67:4024-9. [PMID: 11526000 PMCID: PMC93124 DOI: 10.1128/aem.67.9.4024-4029.2001] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A yellow-pigmented marine bacterium, designated strain SD-21, was isolated from surface sediments of San Diego Bay, San Diego, Calif., based on its ability to oxidize soluble Mn(II) to insoluble Mn(III, IV) oxides. 16S rRNA analysis revealed that this organism was most closely related to members of the genus Erythrobacter, aerobic anoxygenic phototrophic bacteria within the alpha-4 subgroup of the Proteobacteria (alpha-4 Proteobacteria). SD-21, however, has a number of distinguishing phenotypic features relative to Erythrobacter species, including the ability to oxidize Mn(II). During the logarithmic phase of growth, this organism produces Mn(II)-oxidizing factors of approximately 250 and 150 kDa that are heat labile and inhibited by both azide and o-phenanthroline, suggesting the involvement of a metalloenzyme. Although the expression of the Mn(II) oxidase was not dependent on the presence of Mn(II), higher overall growth yields were reached in cultures incubated with Mn(II) in the culture medium. In addition, the rate of Mn(II) oxidation appeared to be slower in cultures grown in the light. This is the first report of Mn(II) oxidation within the alpha-4 Proteobacteria as well as the first Mn(II)-oxidizing proteins identified in a marine gram-negative bacterium.
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Affiliation(s)
- C A Francis
- Marine Biology Research Division and Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093-0202, USA
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16
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Mergaert J, Verhelst A, Cnockaert MC, Tan TL, Swings J. Characterization of facultative oligotrophic bacteria from polar seas by analysis of their fatty acids and 16S rDNA sequences. Syst Appl Microbiol 2001; 24:98-107. [PMID: 11403404 DOI: 10.1078/0723-2020-00012] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
One hundred and seventy three bacterial strains, isolated previously after enrichment under oligotrophic, psychrophylic conditions from Arctic (98 strains) and Antarctic seawater (75 strains), were characterized by gas-liquid chromatographic analysis of their fatty acid compositions. By numerical analysis, 8 clusters, containing 2 to 59 strains, could be delineated, and 8 strains formed separate branches. Five clusters contained strains from both poles, two minor clusters were confined to Arctic isolates, and one cluster consisted of Antarctic isolates only. The 16S rRNA genes from 23 strains, representing the different fatty acid profile clusters and including the unclustered strains, were sequenced. The sequences grouped with the alpha and gamma Proteobacteria, the high percent G+C gram positives, and the Cytophaga-Flavobacterium-Bacteroides branch. The sequences of strains from 4 clusters and of 7 unclustered strains were closely related (sequence similarities above 97%) to reference sequences of Sulfitobacter mediterraneus, Halomonas variabilis, Alteromonas macleodii, Pseudoalteromonas species, Shewanella frigidimarina, and Rhodococcus fascians. Strains from the other four clusters and an unclustered strain showed sequence similarities below 97% with nearest named neighbours, including Rhizobium, Glaciecola, Pseudomonas, Alteromonas macleodii and Cytophaga marinoflava, indicating that the clusters which they represent form as yet unnamed taxa.
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Affiliation(s)
- J Mergaert
- Laboratorium voor Microbiologie, Vakgroep Biochemie, Fysiologie en Microbiologie, Universiteit Gent, Belgium.
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17
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Kaye JZ, Baross JA. High incidence of halotolerant bacteria in Pacific hydrothermal-vent and pelagic environments. FEMS Microbiol Ecol 2000; 32:249-260. [PMID: 10858584 DOI: 10.1111/j.1574-6941.2000.tb00718.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The abundance of halotolerant microorganisms in hydrothermal-vent and pelagic waters in the North and South Pacific was estimated by the most probable number (MPN) technique using a heterotrophic 16% NaCl medium incubated at 20-24 degrees C. Based on these MPNs and direct counts with epifluorescence microscopy to enumerate the total microbial population, salt-tolerant microbes comprised from <0.01 to >28% of the total microbial community. Fourteen isolates from these MPN enrichments were identified by sequencing a portion of the 16S rRNA gene, and all were found to belong to the genera Halomonas and Marinobacter. The response to salt of mesophilic hydrothermal-vent microbial isolates obtained without selecting for salt tolerance was also examined. Forty-one of 65 strains cultured from hydrothermal plume waters, low-temperature hydrothermal fluids, sulfide rock and an animal specimen at approximately 2000-2200 m depth from the Endeavour Segment of the Juan de Fuca Ridge were subjected to increasing concentrations of NaCl, and over half grew at a NaCl concentration that is lethal to many commonly isolated marine bacteria. At least 36 of the 65 isolates (>/=55%) grew in the enrichment medium supplemented with 10% NaCl; at least 30 of 65 (>/=46%) grew with 16% NaCl; at least 20 of 65 (>/=31%) tolerated 22% NaCl. Based on phylogenetic analysis of the 16S rRNA gene in nine of these 65 isolates, four belonged to the genus Halomonas. These Halomonas strains tolerated 22-27% NaCl. It is possible that a majority of the other 16 isolates which grew with 22% NaCl are also Halomonas based on their degree of halotolerance, morphology, and apparent abundance as revealed by MPN enrichments. The four Halomonas strains obtained without selecting for halotolerance were further characterized physiologically and metabolically. Overall, they grew between -1 degrees C and 40 degrees C, were facultative aerobes, oxidized between 49 and 70 organic compounds according to Biolog plate substrate utilization matrices, grew with oligotrophic quantities of carbon (0.002% yeast extract) in liquid media, reduced nitrate to nitrite, and tolerated up to 0.05-3 mM Cd(2+). Halomonas is one of the most abundant culturable organisms in the ocean, and its success may be attributed to its metabolic and physiological versatility.
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Affiliation(s)
- JZ Kaye
- University of Washington, School of Oceanography, Box 357940, 98195-7940, Seattle, WA, USA
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18
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Fisk MR, Giovannoni SJ. Sources of nutrients and energy for a deep biosphere on Mars. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999je900010] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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19
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Shively JM, van Keulen G, Meijer WG. Something from almost nothing: carbon dioxide fixation in chemoautotrophs. Annu Rev Microbiol 1999; 52:191-230. [PMID: 9891798 DOI: 10.1146/annurev.micro.52.1.191] [Citation(s) in RCA: 170] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The last decade has seen significant advances in our understanding of the physiology, ecology, and molecular biology of chemoautotrophic bacteria. Many ecosystems are dependent on CO2 fixation by either free-living or symbiotic chemoautotrophs. CO2 fixation in the chemoautotroph occurs via the Calvin-Benson-Bassham cycle. The cycle is characterized by three unique enzymatic activities: ribulose bisphosphate carboxylase/oxygenase, phosphoribulokinase, and sedoheptulose bisphosphatase. Ribulose bisphosphate carboxylase/oxygenase is commonly found in the cytoplasm, but a number of bacteria package much of the enzyme into polyhedral organelles, the carboxysomes. The carboxysome genes are located adjacent to cbb genes, which are often, but not always, clustered in large operons. The availability of carbon and reduced substrates control the expression of cbb genes in concert with the LysR-type transcriptional regulator, CbbR. Additional regulatory proteins may also be involved. All of these, as well as related topics, are discussed in detail in this review.
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Affiliation(s)
- J M Shively
- Department of Biological Sciences, Clemson University, South Carolina 29634, USA.
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Horken KM, Tabita FR. Closely related form I ribulose bisphosphate carboxylase/oxygenase molecules that possess different CO2/O2 substrate specificities. Arch Biochem Biophys 1999; 361:183-94. [PMID: 9882445 DOI: 10.1006/abbi.1998.0979] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The deduced primary sequence (cbbL and cbbS) of form I ribulose 1, 5-bisphosphate carboxylase/oxygenase (rubisco) from Bradyrhizobium japonicum places this enzyme within the Type IC subgroup of red-like rubisco enzymes. In addition, B. japonicum appears to organize most of the structural genes of the Calvin-Benson-Bassham (CBB) pathway in at least one major operon. Functional expression and characterization of the B. japonicum and Xanthobacter flavus enzymes from this group revealed that these molecules exhibit diverse kinetic properties despite their relatively high degree of sequence relatedness. Of prime importance was the fact that these closely related enzymes exhibited CO2 and O2 substrate specificities that varied from relatively low values [tau = (VcKo)/(VoKc) = 45] to values that approximated those obtained for higher plants (tau = 75). These results, combined with the metabolic and genetic versatility of the organisms from which these enzymes were derived, suggest a potential rich resource for future biological selection and structure-function studies aimed at elucidating structural features that govern key enzymological properties of rubisco.
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Affiliation(s)
- K M Horken
- Department of Microbiology, Ohio State University, 484 West 12th Avenue, Columbus, Ohio, 43210-1292, USA
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21
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Caspi R, Tebo BM, Haygood MG. c-type cytochromes and manganese oxidation in Pseudomonas putida MnB1. Appl Environ Microbiol 1998; 64:3549-55. [PMID: 9758766 PMCID: PMC106463 DOI: 10.1128/aem.64.10.3549-3555.1998] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas putida MnB1 is an isolate from an Mn oxide-encrusted pipeline that can oxidize Mn(II) to Mn oxides. We used transposon mutagenesis to construct mutants of strain MnB1 that are unable to oxidize manganese, and we characterized some of these mutants. The mutants were divided into three groups: mutants defective in the biogenesis of c-type cytochromes, mutants defective in genes that encode key enzymes of the tricarboxylic acid cycle, and mutants defective in the biosynthesis of tryptophan. The mutants in the first two groups were cytochrome c oxidase negative and did not contain c-type cytochromes. Mn(II) oxidation capability could be recovered in a c-type cytochrome biogenesis-defective mutant by complementation of the mutation.
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Affiliation(s)
- R Caspi
- Scripps Institution of Oceanography, University of California in San Diego, La Jolla, California 92093-0202, USA
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22
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Kusian B, Bowien B. Organization and regulation of cbb CO2 assimilation genes in autotrophic bacteria. FEMS Microbiol Rev 1997; 21:135-55. [PMID: 9348665 DOI: 10.1111/j.1574-6976.1997.tb00348.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The Calvin-Benson-Bassham cycle constitutes the principal route of CO2 assimilation in aerobic chemoautotrophic and in anaerobic phototrophic purple bacteria. Most of the enzymes of the cycle are found to be encoded by cbb genes. Despite some conservation of the internal gene arrangement cbb gene clusters of the various organisms differ in size and operon organization. The cbb operons of facultative autotrophs are more strictly regulated than those of obligate autotrophs. The major control is exerted by the cbbR gene, which codes for a transcriptional activator of the LysR family. This gene is typically located immediately upstream of and in divergent orientation to the regulated cbb operon, forming a control region for both transcriptional units. Recent studies suggest that additional protein factors are involved in the regulation. Although the metabolic signal(s) received by the regulatory components of the operons is (are) still unknown, the redox state of the cell is believed to play a key role. It is proposed that the control of the cbb operon expression is integrated into a regulatory network.
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Affiliation(s)
- B Kusian
- Institut für Mikrobiologie, Georg-August-Universität Göttingen, Germany
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23
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Pichard SL, Campbell L, Paul JH. Diversity of the ribulose bisphosphate carboxylase/oxygenase form I gene (rbcL) in natural phytoplankton communities. Appl Environ Microbiol 1997; 63:3600-6. [PMID: 9293012 PMCID: PMC168667 DOI: 10.1128/aem.63.9.3600-3606.1997] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The phytoplankton of the world's oceans play an integral part in global carbon cycling and food webs by conversion of carbon dioxide into organic carbon. They accomplish this task through the action of the Calvin cycle enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). Here we have investigated the phylogenetic diversity in the form I rbcL locus in natural phytoplankton communities of the open ocean and representative clones of marine autotrophic picoplankton by mRNA or DNA amplification and sequencing of a 480 to 483 bp internal fragment of this gene. Five gene sequences were recovered from nucleic acids of natural phytoplankton communities of the Gulf of Mexico. The rbcL genes of two Prochlorococcus isolates and one Synechococcus strain (WH8007) were also sequenced. Sequences were aligned with the database of rbcL genes and subjected to both neighbor-joining and parsimony analyses. The five sequences from the natural phytoplankton community spanned nearly the entire diversity of characterized form I rbcL genes, with some sequences closely related to isolates such as Synechococcus and Prochlorococcus (forms IA and I) and prymnesiophyte algae (form ID), while other sequences were deeply rooted. Unexpectedly, the deep euphotic zone contained an organism that possesses a transcriptionally active rbcL gene closely related to that of a recently characterized manganese-oxidizing bacterium, suggesting that such chemoautotrophs may contribute to the diversity of carbon-fixing organisms in the marine euphotic zone.
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Affiliation(s)
- S L Pichard
- Department of Marine Science, University of South Florida, St. Petersburg 33701, USA
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