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Guido A, Calcagnile M, Talà A, Tredici SM, Belmonte G, Alifano P. Microbial consortium involved in ferromanganese and francolite biomineralization in an anchialine environment (Zinzulùsa Cave, Castro, Italy). THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 936:173423. [PMID: 38797412 DOI: 10.1016/j.scitotenv.2024.173423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 05/03/2024] [Accepted: 05/19/2024] [Indexed: 05/29/2024]
Abstract
Tidally-influenced subterranean settings represent natural geomicrobiological laboratories, relatively unexplored, that facilitate the investigation of new biomineralization processes. The unusual water chemistry of Zinzulùsa Cave and its oligotrophic and aphotic conditions have allowed the development of a unique ecosystem in which complex bacterial activities induce rare biomineralization processes. A diversified microbial community develops on centimeter-thick crusts that form in the submerged part of the cave. The crusts are formed of Ca-phosphate minerals, mostly carbonate-fluoroapatite (francolite), covered by a black crust, few microns in thickness, composed of ferromanganiferous oxides (hematite and vernadite). Diffuse coccoidal and filamentous bacteria and amorphous organic matter are mixed with the minerals. The micromorphologies and comparative 16S rRNA gene-based metabarcoding analyses identify a "core microbiota" also common to other natural environments characterized by FeMn and Ca-phosphate mineralization. The microbiota is characterized by nitrifying, sulfide/sulfur/thiosulfate-oxidizing and sulfate/thiosulfate/sulfur-reducing bacteria. In addition, manganese-oxidizing bacteria include the recently described "Ca. Manganitrophus noduliformans" and an abundance of bacteria belonging to the Planctomycetes-Verrucomicrobia-Chlamydiae (PVC) superphylum, as well as Haliangiales (fruiting body-forming bacteria) and Hyphomicrobiales (stalked and budding bacteria) that are known to produce extracellular polymers that trap iron and manganese oxides. 16S rRNA gene metabarcoding analysis showed the presence of bacteria able to utilize many organic P substrates, including Ramlibacter, and SEM images revealed traces of fossilized microorganisms resembling "cable bacteria", which may play a role in Ca-phosphate biomineralization. Overall, the data indicate biomineralization processes induced by microbial metabolic activities for both ferromanganiferous oxide and francolite components of these crusts.
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Affiliation(s)
- Adriano Guido
- Department of Biology, Ecology and Earth Sciences, University of Calabria, Rende, Cosenza, Italy.
| | - Matteo Calcagnile
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy.
| | - Adelfia Talà
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy.
| | | | - Genuario Belmonte
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy.
| | - Pietro Alifano
- Department of Experimental Medicine, University of Salento, Lecce, Italy.
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Jiang Y, Zhao J, Zhang D. Manganese Dioxide-Based Nanomaterials for Medical Applications. ACS Biomater Sci Eng 2024; 10:2680-2702. [PMID: 38588342 DOI: 10.1021/acsbiomaterials.3c01852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Manganese dioxide (MnO2) nanomaterials can react with trace hydrogen peroxide (H2O2) to produce paramagnetic manganese (Mn2+) and oxygen (O2), which can be used for magnetic resonance imaging and alleviate the hypoxic environment of tumors, respectively. MnO2 nanomaterials also can oxidize glutathione (GSH) to produce oxidized glutathione (GSSG) to break the balance of intracellular redox reactions. As a consequence of the sensitivity of the tumor microenvironment to MnO2-based nanomaterials, these materials can be used as multifunctional diagnostic and therapeutic platforms for tumor imaging and treatment. Importantly, when MnO2 nanomaterials are implanted along with other therapeutics, synergetic tumor therapy can be achieved. In addition to tumor treatment, MnO2-based nanomaterials display promising prospects for tissue repair, organ protection, and the treatment of other diseases. Herein, we provide a thorough review of recent progress in the use of MnO2-based nanomaterials for biomedical applications, which may be helpful for the design and clinical translation of next-generation MnO2 nanomaterials.
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Affiliation(s)
- Yuting Jiang
- Department of Chemistry, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Jiayi Zhao
- Department of Chemistry, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Dinglin Zhang
- Department of Chemistry, College of Basic Medicine, Army Medical University (Third Military Medical University), Chongqing 400038, China
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Marques Mendonca R, Fulton T, Blackwood C, Costello D. Sublethal nickel toxicity shuts off manganese oxidation and pellicle biofilm formation in Pseudomonas putida GB-1. Environ Microbiol 2023; 25:3639-3654. [PMID: 37875338 DOI: 10.1111/1462-2920.16529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 10/11/2023] [Indexed: 10/26/2023]
Abstract
In sediments, the bioavailability and toxicity of Ni are strongly influenced by its sorption to manganese (Mn) oxides, which largely originate from the redox metabolism of microbes. However, microbes are concurrently susceptible to the toxic effects of Ni, which establishes complex interactions between toxicity and redox processes. This study measured the effect of Ni on growth, pellicle biofilm formation and oxidation of the Mn-oxidizing bacteria Pseudomonas putida GB-1. In liquid media, Ni exposure decreased the intrinsic growth rate but allowed growth to the stationary phase in all intermediate treatments. Manganese oxidation was 67% less than control for bacteria exposed to 5 μM Ni and completely ceased in all treatments above 50 μM. Pellicle biofilm development decreased exponentially with Ni concentration (maximum 92% reduction) and was replaced by planktonic growth in higher Ni treatments. In solid media assays, growth was unaffected by Ni exposure, but Mn oxidation completely ceased in treatments above 10 μM of Ni. Our results show that sublethal Ni concentrations substantially alter Mn oxidation rates and pellicle biofilm development in P. putida GB-1, which has implications for toxic metal bioavailability to the entire benthic community and the environmental consequences of metal contamination.
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Affiliation(s)
| | - Taylor Fulton
- Department of Biological Sciences, Kent State University, Kent, Ohio, USA
- Department of Food, Agricultural and Biological Engineering, Ohio State University, Columbus, Ohio, USA
| | - Christopher Blackwood
- Department of Biological Sciences, Kent State University, Kent, Ohio, USA
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, Michigan, USA
| | - David Costello
- Department of Biological Sciences, Kent State University, Kent, Ohio, USA
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Ren CY, Xu QJ, Alvarez PJJ, Zhu L, Zhao HP. Simultaneous antibiotic removal and mitigation of resistance induction by manganese bio-oxidation process. WATER RESEARCH 2023; 244:120442. [PMID: 37549546 DOI: 10.1016/j.watres.2023.120442] [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: 06/21/2023] [Revised: 07/31/2023] [Accepted: 08/01/2023] [Indexed: 08/09/2023]
Abstract
Microbial degradation to remove residual antibiotics in wastewater is of growing interest. However, biological treatment of antibiotics may cause resistance dissemination by mutations and horizontal gene transfer (HGT) of antibiotic resistance genes (ARGs). In this study, a Mn(Ⅱ)-oxidizing bacterium (MnOB), Pseudomonas aeruginosa MQ2, simultaneously degraded antibiotics, decreased HGT, and mitigated antibiotic resistance mutation. Intracellular Mn(II) levels increased during manganese oxidation, and biogenic manganese oxides (BioMnOx, including Mn(II), Mn(III) and Mn(IV)) tightly coated the cell surface. Mn(II) bio-oxidation mitigated antibiotic resistance acquisition from an E. coli ARG donor and mitigated antibiotic resistance inducement by decreasing conjugative transfer and mutation, respectively. BioMnOx also oxidized ciprofloxacin (1 mg/L) and tetracycline (5 mg/L), respectively removing 93% and 96% within 24 h. Transcriptomic analysis revealed that two new multicopper oxidase and one peroxidase genes are involved in Mn(II) oxidation. Downregulation of SOS response, multidrug resistance and type Ⅳ secretion system related genes explained that Mn(II) and BioMnOx decreased HGT and mitigated resistance mutation by alleviating oxidative stress, which makes recipient cells more vulnerable to ARG acquisition and mutation. A manganese bio-oxidation based reactor was constructed and completely removed tetracycline with environmental concentration within 4-hour hydraulic retention time. Overall, this study suggests that Mn (II) bio-oxidation process could be exploited to control antibiotic contamination and mitigate resistance propagation during water treatment.
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Affiliation(s)
- Chong-Yang Ren
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Qiu-Jin Xu
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Pedro J J Alvarez
- Department of Civil and Environmental Engineering, Rice University, Houston 77005, United States
| | - Lizhong Zhu
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - He-Ping Zhao
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China.
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Alvares JJ, Gaonkar SK, Naik CC, Asogekar P, Furtado IJ. Characterization of Mn 3 O 4 -MnO 2 nanocomposites biosynthesized by cell lysate of Haloferax alexandrinus GUSF-1. J Basic Microbiol 2023; 63:996-1006. [PMID: 37160695 DOI: 10.1002/jobm.202300023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 04/13/2023] [Accepted: 04/20/2023] [Indexed: 05/11/2023]
Abstract
Manganese oxide nanocomposites attract huge attention in various biotechnological fields due to their extensive catalytic properties. This study reports an easy, rapid, and cost-effective method of using the cell lysate of haloarchaeon, Haloferax alexandrinus GUSF-1 for the synthesis of manganese oxide nanoparticles. The reaction between the cell lysate and manganese sulfate resulted in the formation of a dark brown precipitate within 48 h at room temperature. The X-ray diffraction pattern showed the existence of Mn3 O4 and MnO2 phases consistent with the JCPDS card no. (01-075-1560 and 00-050-0866). The dark brown colloidal suspension of MnO3 -MnO2 in methanol showed maximum absorption between 220 and 260 nm. The EDX spectrum confirmed the presence of manganese and oxygen. The Transmission electron microscopy revealed the spherical morphology with an average particle size between 30 and 60 nm. The magnetic moment versus magnetic field (MH) curve, at room temperature (300 K) did not saturate even at a high magnetic field (±3T) indicating the paramagnetic nature of the prepared nanocomposite. The Atomic Emission Spectroscopic analysis showed a negligible amount of soluble manganese (0.03 ppm in 50 ppm) in the Mn3 O4 -MnO2 suspension suggesting the maximum stability of the material in the solvent over time. Interstingly, Mn3 O4 -MnO2 nanocomposites evidenced antimicrobial activity in the order of Pseudomonas aeruginosa > Salmonella typhi > Escherichia coli > Proteus vulgaris > Candida albicans > Staphylococcus aureus. Conclusively, this is the first report on the formation of Mn3 O4 -MnO2 nanocomposites using cell lysate of salt pan haloarcheon Haloferax alexandrinus GUSF-1 with antimicrobial potential.
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Affiliation(s)
- Jyothi J Alvares
- Microbiology Programme, School of Biological Sciences and Biotechnology, Goa University, Taleigao, Goa, India
| | - Sanket K Gaonkar
- Microbiology Programme, School of Biological Sciences and Biotechnology, Goa University, Taleigao, Goa, India
- Department of Microbiology, P.E.S's R.S.N College of Arts and Science, Farmagudi, Ponda-Goa, India
| | - Chandan C Naik
- Department of Chemistry, Dhempe College of Arts & Science, Panaji, Goa, India
| | - Pratik Asogekar
- School of Chemical Sciences, Goa University, Taleigao, Goa, India
- Department of Chemistry, P.E.S's R.S.N College of Arts and Science, Farmagudi, Ponda-Goa, India
| | - Irene J Furtado
- Microbiology Programme, School of Biological Sciences and Biotechnology, Goa University, Taleigao, Goa, India
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Nivetha N, Srivarshine B, Sowmya B, Rajendiran M, Saravanan P, Rajeshkannan R, Rajasimman M, Pham THT, Shanmugam V, Dragoi EN. A comprehensive review on bio-stimulation and bio-enhancement towards remediation of heavy metals degeneration. CHEMOSPHERE 2023; 312:137099. [PMID: 36372332 DOI: 10.1016/j.chemosphere.2022.137099] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/20/2022] [Accepted: 10/30/2022] [Indexed: 06/16/2023]
Abstract
Pollution of heavy metals is one of the risky contaminations that should be managed for all intents and purposes of general well-being concerns. The bioaccumulation of these heavy metals inside our bodies and pecking orders will influence our people in the future. Bioremediation is a bio-mechanism where residing organic entities use and reuse the squanders that are reused to one more form. This could be accomplished by taking advantage of the property of explicit biomolecules or biomass that is equipped for restricting by concentrating the necessary heavy metal particles. The microorganisms can't obliterate the metal yet can change it into a less harmful substance. In this unique circumstance, this review talks about the sources, poisonousness, impacts, and bioremediation strategies of five heavy metals: lead, mercury, arsenic, chromium, and manganese. The concentrations here are the ordinary strategies for bioremediation such as biosorption methods, the use of microbes, green growth, and organisms, etc. This review demonstrates the toxicity of heavy metal contamination degradation by biotransformation through bacterioremediation and biodegradation through mycoremediation.
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Affiliation(s)
- N Nivetha
- School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India
| | - B Srivarshine
- School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India
| | - B Sowmya
- School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India
| | | | - Panchamoorthy Saravanan
- Department of Petrochemical Technology, UCE - BIT Campus, Anna University, Tiruchirappalli, Tamil Nadu, India
| | - R Rajeshkannan
- Department of Chemical Engineering, Annamalai University, Tamilnadu, India
| | - M Rajasimman
- Department of Chemical Engineering, Annamalai University, Tamilnadu, India
| | - Thi Hong Trang Pham
- Institute for Global Health Innovations, Duy Tan University, Da Nang, 550000, Viet Nam; Faculty of Natural Science, Duy Tan University, Da Nang, 550000, Viet Nam
| | - VenkatKumar Shanmugam
- School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India.
| | - Elena-Niculina Dragoi
- "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, "Gheorghe Asachi" Technical University, Iasi, Bld Mangeron No 73, 700050, Romania
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Cyclic di-GMP Signaling Links Biofilm Formation and Mn(II) Oxidation in Pseudomonas resinovorans. mBio 2022; 13:e0273422. [PMID: 36374078 PMCID: PMC9765421 DOI: 10.1128/mbio.02734-22] [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] [Indexed: 11/16/2022] Open
Abstract
Bioaugmentation of biological sand filters with Mn(II)-oxidizing bacteria (MOB) is used to increase the efficiency of Mn removal from groundwater. While the biofilm-forming ability of MOB is important to achieve optimal Mn filtration, the regulatory link between biofilm formation and Mn(II) oxidation remains unclear. Here, an environmental isolate of Pseudomonas resinovorans strain MOB-513 was used as a model to investigate the role of c-di-GMP, a second messenger crucially involved in the regulation of biofilm formation by Pseudomonas, in the oxidation of Mn(II). A novel role for c-di-GMP in the upregulation of Mn(II) oxidation through induction of the expression of manganese-oxidizing peroxidase enzymes was revealed. MOB-513 macrocolony biofilms showed a strikingly stratified pattern of biogenic Mn oxide (BMnOx) accumulation in a localized top layer. Remarkably, elevated cellular levels of c-di-GMP correlated not only with increased accumulation of BMnOx in the same top layer but also with the appearance of a second BMnOx stratum in the bottom region of macrocolony biofilms, and the expression of mop genes correlated with this pattern. Proteomic analysis under Mn(II) conditions revealed changes in the abundance of a PilZ domain protein. Subsequent analyses supported a model in which this protein sensed c-di-GMP and affected a regulatory cascade that ultimately inhibited mop gene expression, providing a molecular link between c-di-GMP signaling and Mn(II) oxidation. Finally, we observed that high c-di-GMP levels were correlated with higher lyophilization efficiencies and higher groundwater Mn(II) oxidation capacities of freeze-dried bacterial cells, named lyophiles, showing the biotechnological relevance of understanding the role of c-di-GMP in MOB-513. IMPORTANCE The presence of Mn(II) in groundwater, a common source of drinking water, is a cause of water quality impairment, interfering with its disinfection, causing operation problems, and affecting human health. Purification of groundwater containing Mn(II) plays an important role in environmental and social safety. The typical method for Mn(II) removal is based on bacterial oxidation of metals to form insoluble oxides that can be filtered out of the water. Evidence of reducing the start-up periods and enhancing Mn removal efficiencies through bioaugmentation with appropriate biofilm-forming and MOB has emerged. As preliminary data suggest a link between these two phenotypes in Pseudomonas strains, the need to investigate the underlying regulatory mechanisms is apparent. The significance of our research lies in determining the role of c-di-GMP for increased biofilm formation and Mn(II)-oxidizing capabilities in MOB, which will allow the generation of super-biofilm-elaborating and Mn-oxidizing strains, enabling their implementation in biotechnological applications.
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Ciancio Casalini L, Piazza A, Masotti F, Garavaglia BS, Ottado J, Gottig N. Manganese oxidation counteracts the deleterious effect of low temperatures on biofilm formation in Pseudomonas sp. MOB-449. Front Mol Biosci 2022; 9:1015582. [DOI: 10.3389/fmolb.2022.1015582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/10/2022] [Indexed: 11/13/2022] Open
Abstract
Mn removal from groundwater by biological sand filter technology is negatively impacted by low temperatures in winter periods. Therefore, the need to study Mn(II)-oxidizing bacteria (MOB) having the potential to oxidize Mn(II) and form biofilms at low temperatures is imperative. These MOB can have potential as inocula for sand filter bioaugmentation strategies to optimize Mn removal during winter periods. We previously showed that a Pseudomonas sp. MOB-449 (MOB-449), isolated from a Mn biofilter, oxidizes Mn(II) in a biofilm-dependent way at low temperatures. In this work, MOB-449 Mn(II) oxidation and growth capacities were evaluated under planktonic and biofilm conditions at different temperatures. At 18°C, MOB-449 showed enhanced biofilm formation due to the addition of Mn(II) to the medium correlating with Mn(II) oxidation, compared to biofilms grown in control medium. Moreover, this enhancement on biofilm formation due to the addition of Mn(II) was only observed at 18°C. At this temperature, Mn(II) oxidation in membrane fractions collected from biofilms was induced by uncoupling oxidative phosphorylation from the electron transport chain with 2,4-Dinitrophenol. In Pseudomonas, a role for c-type cytochrome in Mn(II) oxidation has been demonstrated. Accordingly, transcriptional profiles of all terminal oxidases genes found in MOB-449 showed an induction of cytochrome c terminal oxidases expression mediated by Mn(II) oxidation at 18°C. Finally, heme peroxidase activity assays and MS analysis revealed that PetC, a cytochrome c5, and also CcmE, involved in the cytochrome c biogenesis machinery, are induced at 18°C only in the presence of Mn(II). These results present evidence supporting that cytochromes c and also the cytochrome c terminal oxidases are activated at low temperatures in the presence of Mn(II). Overall, this work demonstrate that in MOB-449 Mn(II) oxidation is activated at low temperatures to gain energy, suggesting that this process is important for survival under adverse environmental conditions and contributing to the understanding of the physiological role of bacterial Mn(II) oxidation.
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Song F, Zhang G, Li H, Ma L, Yang N. Comparative transcriptomic analysis of Stenotrophomonas sp. MNB17 revealed mechanisms of manganese tolerance at different concentrations and the role of histidine biosynthesis in manganese removal. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 244:114056. [PMID: 36075124 DOI: 10.1016/j.ecoenv.2022.114056] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 08/21/2022] [Accepted: 09/03/2022] [Indexed: 06/15/2023]
Abstract
Bacteria possess protective mechanisms against excess Mn(Ⅱ) to reduce its toxicity. Stenotrophomonas sp. MNB17 showed high Mn(Ⅱ) removal capacity (92.24-99.16 %) by forming Mn-precipitates (MnCO3 and Mn-oxides), whose Mn-oxides content increased with increasing Mn(Ⅱ) concentrations (10-50 mM). Compared with 0 mM Mn(Ⅱ)-stressed cells, transcriptomic analysis identified genes with the same transcriptional trends in 10 mM and 50 mM Mn(Ⅱ)-stressed cells, including genes involved in metal transport, cell envelope homeostasis, and histidine biosynthesis, as well as genes with different transcriptional trends, such as those involved in oxidative stress response, glyoxylate cycle, electron transport, and protein metabolism. The upregulation of histidine biosynthesis and oxidative stress responses were the most prominent features of these metabolisms under Mn(Ⅱ) stress. We confirmed that the increased level of reactive oxygen species was one of the reasons for the increased Mn-oxides formation at high Mn(Ⅱ) concentrations. Metabolite analysis indicated that the enhanced histidine biosynthesis rather than the tricarboxylic acid cycle resulted in an elevated level of α-ketoglutarate, which helped eliminate reactive oxygen species. Consistent with these results, the exogenous addition of histidine significantly reduced the production of reactive oxygen species and Mn-oxides and enhanced the removal of Mn(Ⅱ) as MnCO3. This study is the first to correlate histidine biosynthesis, reactive oxygen species, and Mn-oxides formation at high Mn(Ⅱ) concentrations, providing novel insights into the molecular regulatory mechanisms associated with Mn(Ⅱ) removal in bacteria.
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Affiliation(s)
- Fuhang Song
- School of Light Industry, Beijing Technology and Business University, 11 Fucheng Road, Beijing 100048, China
| | - Guoliang Zhang
- Center of Deep Sea Research, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China
| | - Honghua Li
- School of Light Industry, Beijing Technology and Business University, 11 Fucheng Road, Beijing 100048, China
| | - Linlin Ma
- Griffith Institute for Drug Discovery, Griffith University, Australia; School of Environment and Science, Griffith University, Australia
| | - Na Yang
- CAS Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Qingdao 266237, China.
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Zhao G, Wang W, Zheng L, Chen L, Duan G, Chang R, Chen Z, Zhang S, Dai M, Yang G. Catalase-peroxidase StKatG is a bacterial manganese oxidase from endophytic Salinicola tamaricis. Int J Biol Macromol 2022; 224:281-291. [DOI: 10.1016/j.ijbiomac.2022.10.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/09/2022] [Accepted: 10/13/2022] [Indexed: 11/05/2022]
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Li H, Wu Y, Tang Y, Fang B, Luo P, Yang L, Jiang Q. A manganese-oxidizing bacterium-Enterobacter hormaechei strain DS02Eh01: Capabilities of Mn(II) immobilization, plant growth promotion and biofilm formation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 309:119775. [PMID: 35843452 DOI: 10.1016/j.envpol.2022.119775] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 07/06/2022] [Accepted: 07/10/2022] [Indexed: 06/15/2023]
Abstract
While biogenic Mn oxides (BioMnOx) generated by Mn(II)-oxidizing bacteria (MOB) have attracted increasing attention, a MOB strain isolated from Mn-polluted sediments was identified and assigned as Enterobacter hormaechei DS02Eh01. Its Mn(II) immobilization activity, plant growth-promoting traits, and biofilm formation capability were investigated. The results showed that strain DS02Eh01 was found to be able to tolerate Mn(II) up to 122 mM. The strain immobilized Mn(II) in aquatic media mainly through extracellular adsorption, bio-oxidation and pH-induced precipitation as well as manganese oxidation. DS02Eh01-derived BioMnOx are negatively charged and have a larger specific surface area (86.70 m2/g) compared to the previously reported BioMnOx. The strain can immobilize Mn(II) at extreme levels, for instance, when it was exposed to 20 mM Mn(II), about 59% of Mn(II) were found immobilized and 17% of Mn(II) were converted to MnOx. The SEM and TEM observation revealed that the DS02Eh01-derived BioMnOx were aggregates doped with granules and microbial pellets. The precipitated Mn(II) and the Mn(III)/Mn(IV) oxides co-existed in BioMnOx, in which Mn(II) and Mn(IV) were found dominant with Mn(II) accounting for 49.6% and Mn(IV) accounting for 41.3%. DS02Eh01 possesses plant growth-promoting traits and biofilm formation capacity even under Mn(II) exposure. Mn(II) exposure at 5 mM was found to stimulate strain DS02Eh01 to form biofilms, from which, the extracted EPS was mainly composed of aromatic proteins. This study reveals that E. hormaechei strain DS02Eh01 possesses the potential in environmental ecoremediation via coupling processes of macrophytes extraction, biochemical immobilization and biosorption.
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Affiliation(s)
- Huilan Li
- Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials & MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials, School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China; Key Laboratory of Environmental Protection (Guangxi University), Education Department of Guangxi Zhuang Autonomous Region, Nanning, 530004, China
| | - Yu Wu
- Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials & MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials, School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China; Key Laboratory of Environmental Protection (Guangxi University), Education Department of Guangxi Zhuang Autonomous Region, Nanning, 530004, China
| | - Yankui Tang
- Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials & MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials, School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China; Key Laboratory of Environmental Protection (Guangxi University), Education Department of Guangxi Zhuang Autonomous Region, Nanning, 530004, China.
| | - Bo Fang
- Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials & MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials, School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China; Key Laboratory of Environmental Protection (Guangxi University), Education Department of Guangxi Zhuang Autonomous Region, Nanning, 530004, China
| | - Penghong Luo
- Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials & MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials, School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China; Key Laboratory of Environmental Protection (Guangxi University), Education Department of Guangxi Zhuang Autonomous Region, Nanning, 530004, China
| | - Luling Yang
- Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials & MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials, School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China; Key Laboratory of Environmental Protection (Guangxi University), Education Department of Guangxi Zhuang Autonomous Region, Nanning, 530004, China
| | - Qiming Jiang
- Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials & MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials, School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China; Key Laboratory of Environmental Protection (Guangxi University), Education Department of Guangxi Zhuang Autonomous Region, Nanning, 530004, China
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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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13
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Jeyaraj A, Subramanian S. Synthesis, optimization, and characterization of biogenic manganese oxide (BioMnOx) by bacterial isolates from mangrove soils with sorbents property towards different toxic metals. Biometals 2022; 35:429-449. [PMID: 35357611 DOI: 10.1007/s10534-022-00378-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 11/17/2021] [Indexed: 11/02/2022]
Abstract
Manganese oxidizing bacteria, Bacillus mycoides and Bacillus subtilis were isolated from mangrove soils and optimized for the removal of Mn(II) with simultaneous production of biogenic manganese oxide (BioMnOx). The removal rate of Mn(II) was 90% in 48 h for B. mycoides and 72 h for B. subtilis under the optimized conditions at pH 7, temperature 37 °C, 120 rpm, with 1% inoculum containing 10 mM MnCl2. Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Energy dispersive X-Ray analysis (EDAX), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) were used to characterize the synthesized biogenic manganese oxide. BioMnOx by Bacillus mycoides and Bacillus subtilis were identified as Bixbyite (Mn2O3) and Hausmannite (Mn3O4), respectively, with nano-sized monocrystalline nature. BioMnOx of Bacillus subtilis strain was more efficient in the removal of metals Zn and Co than BioMnOx of Bacillus mycoides except for mercury. The removal property of synthesized BioMnOx could be applied to treat multi-metal containing wastewater.
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Affiliation(s)
- Anitha Jeyaraj
- Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore-632014, Tamil Nadu, India
| | - Sangeetha Subramanian
- Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore-632014, Tamil Nadu, India.
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14
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Shobnam N, Sun Y, Mahmood M, Löffler FE, Im J. Biologically mediated abiotic degradation (BMAD) of bisphenol A by manganese-oxidizing bacteria. JOURNAL OF HAZARDOUS MATERIALS 2021; 417:125987. [PMID: 34229371 DOI: 10.1016/j.jhazmat.2021.125987] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 04/28/2021] [Accepted: 04/28/2021] [Indexed: 06/13/2023]
Abstract
Bisphenol A (BPA), a chemical of environmental concern, is recalcitrant under anoxic conditions, but is susceptible to oxidative degradation by manganese(IV)-oxide (MnO2). Microbial Mn(II)-oxidation generates MnO2-bio; however, BPA degradation in cultures of Mn(II)-oxidizing bacteria has not been explored. We assessed MnO2-bio-mediated BPA degradation using three Mn(II)-oxidizing bacteria, Roseobacter sp. AzwK-3b, Erythrobacter sp. SD-21, and Pseudomonas putida GB-1. In cultures of all three strains, enhanced BPA degradation was evident in the presence of Mn(II) compared to replicate incubations without Mn(II), suggesting MnO2-bio mediated BPA degradation. Increased Mn(II) concentrations up to 100 µM resulted in more MnO2-bio formation but the highest BPA degradation rates were observed with 10 µM Mn(II). Compared to abiotic BPA degradation with 10 μM synthetic MnO2, live cultures of strain GB-1 amended with 10 μM Mn(II) consumed 9-fold more BPA at about 5-fold higher rates. Growth of strain AzwK-3b was sensitive to BPA and the organism showed increased tolerance against BPA in the presence of Mn(II), suggesting MnO2-bio alleviated the inhibition by mediating BPA degradation. The findings demonstrate that Mn(II)-oxidizing bacteria contribute to BPA degradation but organism-specific differences exist, and for biologically-mediated-abiotic-degradation (BMAD), Mn-flux, rather than the absolute amount of MnO2-bio, is the key determinant for oxidation activity.
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Affiliation(s)
- Nusrat Shobnam
- Department of Civil Engineering, Kansas State University, Manhattan, KS 66506, USA
| | - Yanchen Sun
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, USA; Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, USA
| | - Maheen Mahmood
- Department of Civil Engineering, Kansas State University, Manhattan, KS 66506, USA
| | - Frank E Löffler
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, USA; Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN 37996, USA; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA; Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN 37996, USA
| | - Jeongdae Im
- Department of Civil Engineering, Kansas State University, Manhattan, KS 66506, USA.
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15
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Martínez-Ruiz EB, Cooper M, Barrero-Canosa J, Haryono MAS, Bessarab I, Williams RBH, Szewzyk U. Genome analysis of Pseudomonas sp. OF001 and Rubrivivax sp. A210 suggests multicopper oxidases catalyze manganese oxidation required for cylindrospermopsin transformation. BMC Genomics 2021; 22:464. [PMID: 34157973 PMCID: PMC8218464 DOI: 10.1186/s12864-021-07766-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 06/03/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cylindrospermopsin is a highly persistent cyanobacterial secondary metabolite toxic to humans and other living organisms. Strain OF001 and A210 are manganese-oxidizing bacteria (MOB) able to transform cylindrospermopsin during the oxidation of Mn2+. So far, the enzymes involved in manganese oxidation in strain OF001 and A210 are unknown. Therefore, we analyze the genomes of two cylindrospermopsin-transforming MOB, Pseudomonas sp. OF001 and Rubrivivax sp. A210, to identify enzymes that could catalyze the oxidation of Mn2+. We also investigated specific metabolic features related to pollutant degradation and explored the metabolic potential of these two MOB with respect to the role they may play in biotechnological applications and/or in the environment. RESULTS Strain OF001 encodes two multicopper oxidases and one haem peroxidase potentially involved in Mn2+ oxidation, with a high similarity to manganese-oxidizing enzymes described for Pseudomonas putida GB-1 (80, 83 and 42% respectively). Strain A210 encodes one multicopper oxidase potentially involved in Mn2+ oxidation, with a high similarity (59%) to the manganese-oxidizing multicopper oxidase in Leptothrix discophora SS-1. Strain OF001 and A210 have genes that might confer them the ability to remove aromatic compounds via the catechol meta- and ortho-cleavage pathway, respectively. Based on the genomic content, both strains may grow over a wide range of O2 concentrations, including microaerophilic conditions, fix nitrogen, and reduce nitrate and sulfate in an assimilatory fashion. Moreover, the strain A210 encodes genes which may convey the ability to reduce nitrate in a dissimilatory manner, and fix carbon via the Calvin cycle. Both MOB encode CRISPR-Cas systems, several predicted genomic islands, and phage proteins, which likely contribute to their genome plasticity. CONCLUSIONS The genomes of Pseudomonas sp. OF001 and Rubrivivax sp. A210 encode sequences with high similarity to already described MCOs which may catalyze manganese oxidation required for cylindrospermopsin transformation. Furthermore, the analysis of the general metabolism of two MOB strains may contribute to a better understanding of the niches of cylindrospermopsin-removing MOB in natural habitats and their implementation in biotechnological applications to treat water.
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Affiliation(s)
- Erika Berenice Martínez-Ruiz
- Chair of Environmental Microbiology, Technische Universität Berlin, Institute of Environmental Technology, Straße des 17. Juni 135, 10623, Berlin, Germany.
| | - Myriel Cooper
- Chair of Environmental Microbiology, Technische Universität Berlin, Institute of Environmental Technology, Straße des 17. Juni 135, 10623, Berlin, Germany.
| | - Jimena Barrero-Canosa
- Chair of Environmental Microbiology, Technische Universität Berlin, Institute of Environmental Technology, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Mindia A S Haryono
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, 119077, Singapore
| | - Irina Bessarab
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, 119077, Singapore
| | - Rohan B H Williams
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, 119077, Singapore
| | - Ulrich Szewzyk
- Chair of Environmental Microbiology, Technische Universität Berlin, Institute of Environmental Technology, Straße des 17. Juni 135, 10623, Berlin, Germany
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16
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An Q, Jin L, Deng S, Li Z, Zhang C. Removal of Mn(II) by a nitrifying bacterium Acinetobacter sp. AL-6: efficiency and mechanisms. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:31218-31229. [PMID: 33599926 DOI: 10.1007/s11356-021-12764-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 01/27/2021] [Indexed: 06/12/2023]
Abstract
A nitrifying bacterium Acinetobacter sp. AL-6 showed a high efficiency of 99.05% for Mn(II) removal within 144 h when the Mn(II) concentration was 200 mg L-1; meanwhile, 64.23% of NH4+-N was removed. With the Mn(II) concentration increased from 25 to 300 mg L-1, bacterial growth and Mn(II) removal were stimulated. However, due to the electron acceptor competition between Mn(II) oxidation and nitrification reactions, the increase in NH4+-N concentration would inhibit Mn(II) removal. By measuring Mn metabolic form and locating oxidative active factors, it was proved that extracellular oxidation effect played a dominant role in the removal process of Mn(II). The self-regulation of pH during strain metabolism further promoted the occurrence of biological Mn oxidation. Characterization results showed that the Mn oxidation products were tightly attached to the surface of the bacteria in the form of flakes. The product crystal composition (mainly MnO2 and Mn2O3), Mn-O functional group, and element level fluctuations confirmed the biological oxidation information. The changes of -OH, N-H, and -CH2 groups and the appearance of new functional groups (such as C-H and C-O) provided more possibilities for Mn ion adsorption and bonding.
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Affiliation(s)
- Qiang An
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, People's Republic of China.
- The Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Chongqing University, Chongqing, 400045, People's Republic of China.
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China.
| | - Lin Jin
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Shuman Deng
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Zheng Li
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Chenyi Zhang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, People's Republic of China
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17
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Abstract
In this study, graphite–metal oxide (Gr–MO) composites were produced and explored as potential anodic catalysts for microbial fuel cells. Fe2O3, Fe3O4, or Mn3O4 were used as a catalyst precursor. The morphology and structure of the fabricated materials were analyzed by scanning electron microscopy and X-ray diffraction, respectively, and their corrosion resistance was examined by linear voltammetry. The manufactured Gr–MO electrodes were tested at applied constant potential +0.2 V (vs. Ag/AgCl) in the presence of pure culture Pseudomonas putida 1046 used as a model biocatalyst. The obtained data showed that the applied poising resulted in a generation of anodic currents, which gradually increased during the long-term experiments, indicating a formation of electroactive biofilms on the electrode surfaces. All composite electrodes exhibited higher electrocatalytic activity compared to the non-modified graphite. The highest current density (ca. 100 mA.m−2), exceeding over eight-fold that with graphite, was achieved with Gr–Mn3O4. The additional analyses performed by cyclic voltammetry and electrochemical impedance spectroscopy supported the changes in the electrochemical activity and revealed substantial differences in the mechanism of current generation processes with the use of different catalysts.
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18
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Murgas CJ, Green SP, Forney AK, Korba RM, An SS, Kitten T, Lucas HR. Intracellular Metal Speciation in Streptococcus sanguinis Establishes SsaACB as Critical for Redox Maintenance. ACS Infect Dis 2020; 6:1906-1921. [PMID: 32329608 DOI: 10.1021/acsinfecdis.0c00132] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Streptococcus sanguinis is an oral commensal bacterium, but it can colonize pre-existing heart valve vegetations if introduced into the bloodstream, leading to infective endocarditis. Loss of Mn- or Fe-cofactored virulence determinants are thought to result in weakening of this bacterium. Indeed, intracellular Mn accumulation mediated by the lipoprotein SsaB, a component of the SsaACB transporter complex, has been shown to promote virulence for endocarditis and O2 tolerance. To delineate intracellular metal-ion abundance and redox speciation within S. sanguinis, we developed a protocol exploiting two spectroscopic techniques, Inductively coupled plasma-optical emission spectrometry (ICP-OES) and electron paramagnetic resonance (EPR) spectroscopy, to respectively quantify total intracellular metal concentrations and directly measure redox speciation of Fe and Mn within intact whole-cell samples. Addition of the cell-permeable siderophore deferoxamine shifts the oxidation states of accessible Fe and Mn from reduced-to-oxidized, as verified by magnetic moment calculations, aiding in the characterization of intracellular metal pools and metal sequestration levels for Mn2+ and Fe. We have applied this methodology to S. sanguinis and an SsaACB knockout strain (ΔssaACB), indicating that SsaACB mediates both Mn and Fe uptake, directly influencing the metal-ion pools available for biological inorganic pathways. Mn supplementation of ΔssaACB returns total intracellular Mn to wild-type levels, but it does not restore wild-type redox speciation or distribution of metal cofactor availability for either Mn or Fe. Our results highlight the biochemical basis for S. sanguinis oxidative resistance, revealing a dynamic role for SsaACB in controlling redox homeostasis by managing the intracellular Fe/Mn composition and distribution.
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Affiliation(s)
- Cody J. Murgas
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Shannon P. Green
- Philips Institute for Oral Health Research, Virginia Commonwealth University, Richmond, Virginia 23298, United States
- Department of Microbiology & Immunology, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Ashley K. Forney
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Rachel M. Korba
- Philips Institute for Oral Health Research, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Seon-Sook An
- Philips Institute for Oral Health Research, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Todd Kitten
- Philips Institute for Oral Health Research, Virginia Commonwealth University, Richmond, Virginia 23298, United States
- Department of Microbiology & Immunology, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Heather R. Lucas
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
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19
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Moura HM, Unterlass MM. Biogenic Metal Oxides. Biomimetics (Basel) 2020; 5:E29. [PMID: 32585892 PMCID: PMC7345149 DOI: 10.3390/biomimetics5020029] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/16/2020] [Accepted: 06/19/2020] [Indexed: 12/11/2022] Open
Abstract
Biogenic metal oxides (MxOy) feature structures as highly functional and unique as the organisms generating them. They have caught the attention of scientists for the development of novel materials by biomimicry. In order to understand how biogenic MxOy could inspire novel technologies, we have reviewed examples of all biogenic MxOy, as well as the current state of understanding of the interactions between the inorganic MxOy and the biological matter they originate from and are connected to. In this review, we first summarize the origins of the precursors that living nature converts into MxOy. From the point-of-view of our materials chemists, we present an overview of the biogenesis of silica, iron and manganese oxides, as the only reported biogenic MxOy to date. These MxOy are found across all five kingdoms (bacteria, protoctista, fungi, plants and animals). We discuss the key molecules involved in the biosynthesis of MxOy, the functionality of the MxOy structures, and the techniques by which the biogenic MxOy can be studied. We close by outlining the biomimetic approaches inspired by biogenic MxOy materials and their challenges, and we point at promising directions for future organic-inorganic materials and their synthesis.
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Affiliation(s)
- Hipassia M. Moura
- Institute of Materials Chemistry, Vienna University of Technology, 1060 Vienna, Austria;
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, 1060 Vienna, Austria
| | - Miriam M. Unterlass
- Institute of Materials Chemistry, Vienna University of Technology, 1060 Vienna, Austria;
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, 1060 Vienna, Austria
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria
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20
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Panchenko O. Biodegrading Properties of the Microbiocenosis of Iron and Manganese Removal Rapid Filters for Groundwater. INNOVATIVE BIOSYSTEMS AND BIOENGINEERING 2020. [DOI: 10.20535/ibb.2020.4.2.204919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
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21
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Wang X, Yu M, Wang L, Lin H, Li B, Xue CX, Sun H, Zhang XH. Comparative genomic and metabolic analysis of manganese-oxidizing mechanisms in Celeribacter manganoxidans DY25 T: Its adaptation to the environment of polymetallic nodules. Genomics 2019; 112:2080-2091. [PMID: 31809796 DOI: 10.1016/j.ygeno.2019.12.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 11/23/2019] [Accepted: 12/02/2019] [Indexed: 11/28/2022]
Abstract
Manganese (Mn) nodule is one of the ubiquitous polymetallic concretions and mainly consists of Mn - Fe oxi-hydroxide precipitations. A primary oxidation of Mn(II) to MnO2, in which microorganisms may play important roles, is followed by agglomeration of MnO2 into nodules. Celeribater manganoxidans DY25T, belonging to family Rhodobacteraceae, has ability to catalyze the formation of MnO2 [1]. The concentration of MnO2 formed by harvested cells reached 7.08 μM after suspended in 10 mM HEPES (pH 7.5). Genomic and physiological characteristics of strain DY25T provided a better understanding of its Mn-oxidizing mechanism. Fifteen genes (including four multicopper oxidases) may be involved in Mn(II)-oxidation, whereas only three of them can promote this process. Sulfur-oxidizing activity was detected, which may be associated with manganese oxidation. Genes involved in import and export of primary elemental ingredients (C, N, P and S) and metallic elements (e.g. Mn) were discovered, demonstrating its potential roles in the biogeochemical cycle.
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Affiliation(s)
- Xiaolei Wang
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Min Yu
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Long Wang
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Heyu Lin
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Bei Li
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Chun-Xu Xue
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Hao Sun
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Xiao-Hua Zhang
- MOE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China; Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China.
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22
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23
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Piazza A, Ciancio Casalini L, Pacini VA, Sanguinetti G, Ottado J, Gottig N. Environmental Bacteria Involved in Manganese(II) Oxidation and Removal From Groundwater. Front Microbiol 2019; 10:119. [PMID: 30853942 PMCID: PMC6396730 DOI: 10.3389/fmicb.2019.00119] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 01/18/2019] [Indexed: 12/22/2022] Open
Abstract
The presence of iron (Fe) and manganese (Mn) in groundwater is an important concern in populations that use it as source of drinking water. The ingestion of high concentrations of these metals may affect human health. In addition, these metals cause aesthetic and organoleptic problems that affect water quality and also induce corrosion in distribution networks, generating operational and system maintenance problems. Biological sand filter systems are widely used to remove Fe and Mn from groundwater since they are a cost-effective technology and minimize the use of chemical oxidants. In this work, the bacterial communities of two biological water treatment plants from Argentina, exposed to long term presence of Mn(II) and with a high Mn(II) removal efficiency, were characterized using 16S rRNA gene Illumina sequencing. Several selective media were used to culture Mn-oxidizing bacteria (MOB) and a large number of known MOB and several isolates that have never been reported before as MOB were cultivated. These bacteria were characterized to select those with the highest Mn(II) oxidation and biofilm formation capacities and also those that can oxidize Mn(II) at different environmental growth conditions. In addition, studies were performed to determine if the selected MOB were able to oxidize Mn(II) present in groundwater while immobilized on sand. This work allowed the isolation of several bacterial strains adequate to develop an inoculum applicable to improve Mn(II) removal efficiency of sand filter water treatment plants.
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Affiliation(s)
- Ainelén Piazza
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Lucila Ciancio Casalini
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Virginia A. Pacini
- Centro de Ingeniería Sanitaria, Universidad Nacional de Rosario, Rosario, Argentina
| | - Graciela Sanguinetti
- Centro de Ingeniería Sanitaria, Universidad Nacional de Rosario, Rosario, Argentina
| | - Jorgelina Ottado
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Universidad Nacional de Rosario (UNR), Rosario, Argentina
- Centro de Ingeniería Sanitaria, Universidad Nacional de Rosario, Rosario, Argentina
| | - Natalia Gottig
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Universidad Nacional de Rosario (UNR), Rosario, Argentina
- Centro de Ingeniería Sanitaria, Universidad Nacional de Rosario, Rosario, Argentina
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24
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Zerfaß C, Asally M, Soyer OS. Interrogating metabolism as an electron flow system. CURRENT OPINION IN SYSTEMS BIOLOGY 2019; 13:59-67. [PMID: 31008413 PMCID: PMC6472609 DOI: 10.1016/j.coisb.2018.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Metabolism is generally considered as a neatly organised system of modular pathways, shaped by evolution under selection for optimal cellular growth. This view falls short of explaining and predicting a number of key observations about the structure and dynamics of metabolism. We highlight these limitations of a pathway-centric view on metabolism and summarise studies suggesting how these could be overcome by viewing metabolism as a thermodynamically and kinetically constrained, dynamical flow system. Such a systems-level, first-principles based view of metabolism can open up new avenues of metabolic engineering and cures for metabolic diseases and allow better insights to a myriad of physiological processes that are ultimately linked to metabolism. Towards further developing this view, we call for a closer interaction among physical and biological disciplines and an increased use of electrochemical and biophysical approaches to interrogate cellular metabolism together with the microenvironment in which it exists.
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Affiliation(s)
- Christian Zerfaß
- Bio-Electrical Engineering (BEE) Innovation Hub, University of Warwick, Coventry, CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Munehiro Asally
- Bio-Electrical Engineering (BEE) Innovation Hub, University of Warwick, Coventry, CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
- Warwick Integrative Synthetic Biology Centre (WISB), University of Warwick, Coventry, CV4 7AL, UK
| | - Orkun S. Soyer
- Bio-Electrical Engineering (BEE) Innovation Hub, University of Warwick, Coventry, CV4 7AL, UK
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
- Warwick Integrative Synthetic Biology Centre (WISB), University of Warwick, Coventry, CV4 7AL, UK
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25
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Zerfaß C, Christie-Oleza JA, Soyer OS. Manganese Oxide Biomineralization Provides Protection against Nitrite Toxicity in a Cell-Density-Dependent Manner. Appl Environ Microbiol 2019; 85:e02129-18. [PMID: 30413475 PMCID: PMC6328764 DOI: 10.1128/aem.02129-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 11/01/2018] [Indexed: 12/12/2022] Open
Abstract
Manganese biomineralization is a widespread process among bacteria and fungi. To date, there is no conclusive experimental evidence for how and if this process impacts microbial fitness in the environment. Here, we show how a model organism for manganese oxidation is growth inhibited by nitrite, and that this inhibition is mitigated in the presence of manganese. We show that such manganese-mediated mitigation of nitrite inhibition is dependent on the culture inoculum size, and that manganese oxide (MnOX) forms granular precipitates in the culture, rather than sheaths around individual cells. We provide evidence that MnOX protection involves both its ability to catalyze nitrite oxidation into (nontoxic) nitrate under physiological conditions and its potential role in influencing processes involving reactive oxygen species (ROS). Taken together, these results demonstrate improved microbial fitness through MnOX deposition in an ecological setting, i.e., mitigation of nitrite toxicity, and point to a key role of MnOX in handling stresses arising from ROS.IMPORTANCE We present here a direct fitness benefit (i.e., growth advantage) for manganese oxide biomineralization activity in Roseobacter sp. strain AzwK-3b, a model organism used to study this process. We find that strain AzwK-3b in a laboratory culture experiment is growth inhibited by nitrite in manganese-free cultures, while the inhibition is considerably relieved by manganese supplementation and manganese oxide (MnOX) formation. We show that biogenic MnOX interacts directly with nitrite and possibly with reactive oxygen species and find that its beneficial effects are established through formation of dispersed MnOX granules in a manner dependent on the population size. These experiments raise the possibility that manganese biomineralization could confer protection against nitrite toxicity to a population of cells. They open up new avenues of interrogating this process in other species and provide possible routes to their biotechnological applications, including in metal recovery, biomaterials production, and synthetic community engineering.
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Affiliation(s)
- Christian Zerfaß
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- Warwick Integrative Synthetic Biology Centre (WISB), University of Warwick, Coventry, United Kingdom
| | - Joseph A Christie-Oleza
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- Warwick Integrative Synthetic Biology Centre (WISB), University of Warwick, Coventry, United Kingdom
| | - Orkun S Soyer
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- Warwick Integrative Synthetic Biology Centre (WISB), University of Warwick, Coventry, United Kingdom
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26
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Zhou NQ, Liu DF, Min D, Cheng L, Huang XN, Tian LJ, Li DB, Yu HQ. Continuous degradation of ciprofloxacin in a manganese redox cycling system driven by Pseudomonas putida MnB-1. CHEMOSPHERE 2018; 211:345-351. [PMID: 30077930 DOI: 10.1016/j.chemosphere.2018.07.117] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 07/16/2018] [Accepted: 07/21/2018] [Indexed: 05/22/2023]
Abstract
Ciprofloxacin (CIP), as an extensively used antibiotic, has been widely detected at a high level in the environment and has raised environmental pollution concerns. Thus, efficient and cost-effective methods for CIP degradation are highly desired. Biologically produced manganese oxides (BioMnOx) offer a promising perspective for CIP degradation because of their catalytic reactivity and cost-effectiveness. However, the release of Mn(II) from BioMnOx prevents the further oxidation of pollutants. As a consequence, continuous CIP degradation by BioMnOx is not feasible. In this work, a manganese redox cycling system driven by Pseudomonas putida MnB-1 was constructed for continuous degradation of CIP. In such a system CIP was oxidized continuously and rapidly by re-oxidizing the formed Mn(II) to regenerate reactive BioMnOx, which also protected the strain from CIP toxicity. CIP was degraded through N-dealkylation passway. No significant loss of BioMnOx reactivity was observed in three-cycle CIP degradation process, suggesting the stability of this system. An overlooked intracellular BioMnOx, which was involved in CIP degradation, was discovered in P. putida MnB-1. Moreover, the important role of Mn(III) in facilitating CIP removal in this system was also identified. This work provides useful information to better understand the degradation of antibiotic compounds mediated by microbes in environments.
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Affiliation(s)
- Nan-Qing Zhou
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Dong-Feng Liu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China.
| | - Di Min
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Lei Cheng
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Xue-Na Huang
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Li-Jiao Tian
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Dao-Bo Li
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China.
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27
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Zheng Y, Li Y, Long H, Zhao X, Jia K, Li J, Wang L, Wang R, Lu X, Zhang D. bifA Regulates Biofilm Development of Pseudomonas putida MnB1 as a Primary Response to H 2O 2 and Mn 2. Front Microbiol 2018; 9:1490. [PMID: 30042743 PMCID: PMC6048274 DOI: 10.3389/fmicb.2018.01490] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 06/15/2018] [Indexed: 12/15/2022] Open
Abstract
Pseudomonas putida (P. putida) MnB1 is a widely used model strain in environment science and technology for determining microbial manganese oxidation. Numerous studies have demonstrated that the growth and metabolism of P. putida MnB1 are influenced by various environmental factors. In this study, we investigated the effects of hydrogen peroxide (H2O2) and manganese (Mn2+) on proliferation, Mn2+ acquisition, anti-oxidative system, and biofilm formation of P. putida MnB1. The related orthologs of 4 genes, mco, mntABC, sod, and bifA, were amplified from P. putida GB1 and their involvement were assayed, respectively. We found that P. putida MnB1 degraded H2O2, and quickly recovered for proliferation, but its intracellular oxidative stress state was maintained, with rapid biofilm formation after H2O2 depletion. The data from mco, mntABC, sod and bifA expression levels by qRT-PCR, elucidated a sensitivity toward bifA-mediated biofilm formation, in contrary to intracellular anti-oxidative system under H2O2 exposure. Meanwhile, Mn2+ ion supply inhibited biofilm formation of P. putida MnB1. The expression pattern of these genes showed that Mn2+ ion supply likely functioned to modulate biofilm formation rather than only acting as nutrient substrate for P. putida MnB1. Furthermore, blockade of BifA activity by GTP increased the formation and development of biofilms during H2O2 exposure, while converse response to Mn2+ ion supply was evident. These distinct cellular responses to H2O2 and Mn2+ provide insights on the common mechanism by which environmental microorganisms may be protected from exogenous factors. We postulate that BifA-mediated biofilm formation but not intracellular anti-oxidative system may be a primary protective strategy adopted by P. putida MnB1. These findings will highlight the understanding of microbial adaptation mechanisms to distinct environmental stresses.
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Affiliation(s)
- Yanjing Zheng
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Yumei Li
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Hongyan Long
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Xiaojuan Zhao
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Keke Jia
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Juan Li
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, China
| | - Leyong Wang
- Key Laboratory of Mesoscopic Chemistry of MOE and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing, China
| | - Ruiyong Wang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Xiancai Lu
- State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, China
| | - Dongmei Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
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28
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Sousa LPD, da Silva MJD, Mondego JMC. Leaf-associated bacterial microbiota of coffee and its correlation with manganese and calcium levels on leaves. Genet Mol Biol 2018; 41:455-465. [PMID: 29782032 PMCID: PMC6082234 DOI: 10.1590/1678-4685-gmb-2017-0255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 10/14/2017] [Indexed: 01/16/2023] Open
Abstract
Coffee is one of the most valuable agricultural commodities and the plants’
leaves are the primary site of infection for most coffee diseases, such as the
devastating coffee leaf rust. Therefore, the use of bacterial microbiota that
inhabits coffee leaves to fight infections could be an alternative agricultural
method to protect against coffee diseases. Here, we report the leaf-associated
bacteria in three coffee genotypes over the course of a year, with the aim to
determine the diversity of bacterial microbiota. The results indicate a
prevalence of Enterobacteriales in Coffea canephora,
Pseudomonadales in C. arabica ‘Obatã’, and an intriguing lack
of bacterial dominance in C. arabica ‘Catuaí’. Using PERMANOVA
analyses, we assessed the association between bacterial abundance in the coffee
genotypes and environmental parameters such as temperature, precipitation, and
mineral nutrients in the leaves. We detected a close relationship between the
amount of Mn and the abundance of Pseudomonadales in ‘Obatã’ and the amount of
Ca and the abundance of Enterobacteriales in C. canephora. We
suggest that mineral nutrients can be key drivers that shape leaf microbial
communities.
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Affiliation(s)
- Leandro Pio de Sousa
- Instituto Agronômico, Campinas, SP, Brazil.,Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia Universidade de Campinas (UNICAMP), Campinas, SP, Brazil.,Programa de Pós Graduação em Genética e Biologia Molecular, Instituto de Biologia, Universidade de Campinas (UNICAMP), Campinas, SP, Brazil
| | - Marcio José da da Silva
- Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade de Campinas (UNICAMP), Campinas, SP, Brazil
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29
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Biogenic manganese oxide nanoparticle formation by a multimeric multicopper oxidase Mnx. Nat Commun 2017; 8:746. [PMID: 28963463 PMCID: PMC5622069 DOI: 10.1038/s41467-017-00896-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 08/02/2017] [Indexed: 12/28/2022] Open
Abstract
Bacteria that produce Mn oxides are extraordinarily skilled engineers of nanomaterials that contribute significantly to global biogeochemical cycles. Their enzyme-based reaction mechanisms may be genetically tailored for environmental remediation applications or bioenergy production. However, significant challenges exist for structural characterization of the enzymes responsible for biomineralization. The active Mn oxidase in Bacillus sp. PL-12, Mnx, is a complex composed of a multicopper oxidase (MCO), MnxG, and two accessory proteins, MnxE and MnxF. MnxG shares sequence similarity with other, structurally characterized MCOs. MnxE and MnxF have no similarity to any characterized proteins. The ~200 kDa complex has been recalcitrant to crystallization, so its structure is unknown. Here, we show that native mass spectrometry defines the subunit topology and copper binding of Mnx, while high-resolution electron microscopy visualizes the protein and nascent Mn oxide minerals. These data provide critical structural information for understanding Mn biomineralization by such unexplored enzymes. Significant challenges exist for structural characterization of enzymes responsible for biomineralization. Here the authors show that native mass spectrometry and high resolution electron microscopy can define the subunit topology and copper binding of a manganese oxidizing complex, and describe early stage formation of its mineral products
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30
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Bak EN, Larsen MG, Moeller R, Nissen SB, Jensen LR, Nørnberg P, Jensen SJK, Finster K. Silicates Eroded under Simulated Martian Conditions Effectively Kill Bacteria-A Challenge for Life on Mars. Front Microbiol 2017; 8:1709. [PMID: 28955310 PMCID: PMC5601068 DOI: 10.3389/fmicb.2017.01709] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 08/23/2017] [Indexed: 11/17/2022] Open
Abstract
The habitability of Mars is determined by the physical and chemical environment. The effect of low water availability, temperature, low atmospheric pressure and strong UV radiation has been extensively studied in relation to the survival of microorganisms. In addition to these stress factors, it was recently found that silicates exposed to simulated saltation in a Mars-like atmosphere can lead to a production of reactive oxygen species. Here, we have investigated the stress effect induced by quartz and basalt abraded in Mars-like atmospheres by examining the survivability of the three microbial model organisms Pseudomonas putida, Bacillus subtilis, and Deinococcus radiodurans upon exposure to the abraded silicates. We found that abraded basalt that had not been in contact with oxygen after abrasion killed more than 99% of the vegetative cells while endospores were largely unaffected. Exposure of the basalt samples to oxygen after abrasion led to a significant reduction in the stress effect. Abraded quartz was generally less toxic than abraded basalt. We suggest that the stress effect of abraded silicates may be caused by a production of reactive oxygen species and enhanced by transition metal ions in the basalt leading to hydroxyl radicals through Fenton-like reactions. The low survivability of the usually highly resistant D. radiodurans indicates that the effect of abraded silicates, as is ubiquitous on the Martian surface, would limit the habitability of Mars as well as the risk of forward contamination. Furthermore, the reactivity of abraded silicates could have implications for future manned missions, although the lower effect of abraded silicates exposed to oxygen suggests that the effects would be reduced in human habitats.
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Affiliation(s)
- Ebbe N Bak
- Department of Bioscience, Aarhus UniversityAarhus, Denmark
| | | | - Ralf Moeller
- Space Microbiology Research Group, Institute of Aerospace Medicine, German Aerospace Center (DLR)Cologne, Germany
| | - Silas B Nissen
- Department of Bioscience, Aarhus UniversityAarhus, Denmark
| | - Lasse R Jensen
- Department of Bioscience, Aarhus UniversityAarhus, Denmark
| | - Per Nørnberg
- Department of Bioscience, Aarhus UniversityAarhus, Denmark
| | | | - Kai Finster
- Department of Bioscience, Aarhus UniversityAarhus, Denmark.,Stellar Astrophysics Center, Department of Physics and Astronomy, Aarhus UniversityAarhus, Denmark
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31
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Tsuji K, Asayama T, Shiraki N, Inoue S, Okuda E, Hayashi C, Nishida K, Hasegawa H, Harada E. Mn accumulation in a submerged plant Egeria densa (Hydrocharitaceae) is mediated by epiphytic bacteria. PLANT, CELL & ENVIRONMENT 2017; 40:1163-1173. [PMID: 28098343 DOI: 10.1111/pce.12910] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Revised: 12/24/2016] [Accepted: 01/04/2017] [Indexed: 06/06/2023]
Abstract
Many aquatic plants act as biosorbents, removing and recovering metals from the environment. To assess the biosorbent activity of Egeria densa, a submerged freshwater macrophyte, plants were collected monthly from a circular drainage area in Lake Biwa basin and the Mn concentrations of the plants were analysed. Mn concentrations in these plants were generally above those of terrestrial hyperaccumulators, and were markedly higher in spring and summer than in autumn. Mn concentrations were much lower in plants incubated in hydroponic medium at various pH levels with and without Mn supplementation than in field-collected plants. The precipitation of Mn oxides on the leaves was determined by variable pressure scanning electron microscopy-energy dispersive X-ray analysis and Leucoberbelin blue staining. Several strains of epiphytic bacteria were isolated from the field-collected E. densa plants, with many of these strains, including those of the genera Acidovorax, Comamonas, Pseudomonas and Rhizobium, found to have Mn-oxidizing activity. High Mn concentrations in E. densa were mediated by the production of biogenic Mn oxide in biofilms on leaf surfaces. These findings provide new insights into plant epidermal bacterial flora that affect metal accumulation in plants and suggest that these aquatic plants may have use in Mn phytomining.
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Affiliation(s)
- Kousuke Tsuji
- Graduate School of Environmental Science, The University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan
| | - Takuma Asayama
- Graduate School of Environmental Science, The University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan
| | - Nozomi Shiraki
- School of Environmental Science, The University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan
| | - Shota Inoue
- School of Environmental Science, The University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan
| | - Erina Okuda
- School of Environmental Science, The University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan
| | - Chizuru Hayashi
- School of Environmental Science, The University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan
| | - Kazuma Nishida
- School of Environmental Science, The University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan
| | - Hiroshi Hasegawa
- School of Environmental Science, The University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan
| | - Emiko Harada
- School of Environmental Science, The University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan
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32
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Mechanistic insights into manganese oxidation of a soil-borne Mn(II)-oxidizing Escherichia coli strain by global proteomic and genetic analyses. Sci Rep 2017; 7:1352. [PMID: 28465578 PMCID: PMC5430989 DOI: 10.1038/s41598-017-01552-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 03/30/2017] [Indexed: 11/20/2022] Open
Abstract
An iTRAQ-based comparative and quantitative proteomics analysis of a soil-borne Mn(II)-oxidizing bacterium, Escherichia coli MB266, was conducted during the exponential and stationary growth phases. A total of 1850 proteins were identified in 4 samples, of which 373 and 456 proteins were significantly up- or down-regulated in at least one pairwise comparison, respectively. The iTRAQ data indicated that several enzymes involved in fatty acid metabolism (i.e., FabA, FabD and FabZ) and pyruvate metabolism (particularly pyruvate oxidase PoxB) were significantly up-regulated, while those related to the tricarboxylic acid cycle (such as FrdB, FumB and AcnA) and methylcitrate cycle (i.e., PrpC) were inactivated in the presence of 1 mM Mn(II); the amounts of some stress response and signal transduction system-related proteins (i.e., Spy) were remarkably increased, and the cold shock protein CspD was significantly up-regulated during the exponential growth phase. However, all verified heat shock proteins remained unchanged. The reactive oxygen species response and some redox enzymes might also be involved in Mn oxidation processes. The involvement of several cellular proteins in Mn(II) oxidation, including PoxB, Spy and MCO266, was further confirmed by gene disruption and expression complementation experiments. Based on these results, a signal transduction mechanism coupled to Mn oxidation was proposed.
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33
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Mohanty S, Ghosh S, Nayak S, Das AP. Bioleaching of manganese by Aspergillus sp. isolated from mining deposits. CHEMOSPHERE 2017; 172:302-309. [PMID: 28086158 DOI: 10.1016/j.chemosphere.2016.12.136] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 12/23/2016] [Accepted: 12/27/2016] [Indexed: 06/06/2023]
Abstract
A comprehensive study on fungus assisted bioleaching of manganese (Mn) was carried out to demonstrate Mn solubilization of collected low grade ore from mining deposits of Sanindipur, Odisha, India. A native fungal strain MSF 5 was isolated and identified as Aspergillus sp. by Inter Transcribed Spacer (ITS) sequencing. The identified strain revealed an elevated tolerance ability to Mn under varying optimizing conditions like initial pH (2, 3, 4, 5, 6, 7), carbon sources (dextrose, sucrose, fructose and glucose) and pulp density (2%, 3%, 4%, 5% and 6%). Bioleaching studies carried out under optimized conditions of 2% pulp density of Mn ore at pH 6, temperature 37 °C and carbon dosage (dextrose) resulted with 79% Mn recovery from the ore sample within 20 days. SEM-EDX characterization of the ore sample and leach residue was carried out and the micrographs demonstrated porous and coagulated precipitates scattered across the matrix. The corresponding approach of FTIR analysis regulating the Mn oxide formation shows a distinctive peak of mycelium cells with and without treated Mn, resulting with generalized vibrations like MnOx stretching and CH2 stretch. Thus, our investigation endeavors' the considerate possible mechanism involved in fungal surface cells onto Mn ore illustrating an alteration in cellular Mn interaction.
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Affiliation(s)
- Sansuta Mohanty
- Bioengineering & Biomineral Processing Laboratory, Centre of Biotechnology, Siksha O Anusandhan University, Khandagiri Square, Bhubaneswar, India
| | - Shreya Ghosh
- Bioengineering & Biomineral Processing Laboratory, Centre of Biotechnology, Siksha O Anusandhan University, Khandagiri Square, Bhubaneswar, India
| | - Sanghamitra Nayak
- Bioengineering & Biomineral Processing Laboratory, Centre of Biotechnology, Siksha O Anusandhan University, Khandagiri Square, Bhubaneswar, India
| | - Alok Prasad Das
- Department of Chemical and Polymer Engineering, Tripura University (A Central University), Suryamaninagar, Tripura, India.
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34
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Abstract
The importance of manganese in the physiology of marine microbes, the biogeochemistry of the ocean and the health of microbial communities of past and present is emerging. Manganese is distributed widely throughout the global ocean, taking the form of an essential antioxidant (Mn2+), a potent oxidant (Mn3+) and strong adsorbent (Mn oxides) sequestering disproportionately high levels of trace metals and nutrients in comparison to the surrounding seawater. Manganese is, in fact, linked to nearly all other elemental cycles and intricately involved in the health, metabolism and function of the ocean's microbiome. Here, we briefly review the diversity of microbes and pathways responsible for the transformation of Mn within the three Mn pools and their distribution within the marine environment. Despite decades of interrogation, we still have much to learn about the players, mechanisms and consequences of the Mn cycle, and new and exciting discoveries are being made at a rapid rate. What is clear is the dynamic and ever-inspiring complexity of reactions involving Mn, and the acknowledgement that microorganisms are the catalytic engine driving the Mn cycle.
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Affiliation(s)
- Colleen M Hansel
- Woods Hole Oceanographic Institution, Woods Hole, MA, United States.
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35
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Tao L, Simonov AN, Romano CA, Butterfield CN, Fekete M, Tebo BM, Bond AM, Spiccia L, Martin LL, Casey WH. Biogenic Manganese-Oxide Mineralization is Enhanced by an Oxidative Priming Mechanism for the Multi-Copper Oxidase, MnxEFG. Chemistry 2016; 23:1346-1352. [PMID: 27726210 DOI: 10.1002/chem.201603803] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Indexed: 11/07/2022]
Abstract
In a natural geochemical cycle, manganese-oxide minerals (MnOx ) are principally formed through a microbial process, where a putative multicopper oxidase MnxG plays an essential role. Recent success in isolating the approximately 230 kDa, enzymatically active MnxEFG protein complex, has advanced our understanding of biogenic MnOx mineralization. Here, the kinetics of MnOx formation catalyzed by MnxEFG are examined using a quartz crystal microbalance (QCM), and the first electrochemical characterization of the MnxEFG complex is reported using Fourier transformed alternating current voltammetry. The voltammetric studies undertaken using near-neutral solutions (pH 7.8) establish the apparent reversible potentials for the Type 2 Cu sites in MnxEFG immobilized on a carboxy-terminated monolayer to be in the range 0.36-0.40 V versus a normal hydrogen electrode. Oxidative priming of the MnxEFG protein complex substantially enhances the enzymatic activity, as found by in situ electrochemical QCM analysis. The biogeochemical significance of this enzyme is clear, although the role of an oxidative priming of catalytic activity might be either an evolutionary advantage or an ancient relic of primordial existence.
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Affiliation(s)
- Lizhi Tao
- Department of Chemistry and Department of Earth and Planetary Sciences, University of California, One Shields Avenue, Davis, California, 95616, USA
| | - Alexandr N Simonov
- School of Chemistry, Monash University, Victoria, 3800, Australia.,ARC Centre of Excellence for Electromaterials Science, Monash University, Victoria, 3800, Australia
| | - Christine A Romano
- Division of Environmental and Biomolecular Systems, Institute of Environmental Health, Oregon Health & Science University, Portland, Oregon, 97239, USA
| | - Cristina N Butterfield
- Division of Environmental and Biomolecular Systems, Institute of Environmental Health, Oregon Health & Science University, Portland, Oregon, 97239, USA.,Current address: Department of Earth and Planetary Science, University of California Berkeley, Berkeley, California, 94720, USA
| | - Monika Fekete
- School of Chemistry, Monash University, Victoria, 3800, Australia
| | - Bradley M Tebo
- Division of Environmental and Biomolecular Systems, Institute of Environmental Health, Oregon Health & Science University, Portland, Oregon, 97239, USA
| | - Alan M Bond
- School of Chemistry, Monash University, Victoria, 3800, Australia
| | - Leone Spiccia
- School of Chemistry, Monash University, Victoria, 3800, Australia.,ARC Centre of Excellence for Electromaterials Science, Monash University, Victoria, 3800, Australia
| | | | - William H Casey
- Department of Chemistry and Department of Earth and Planetary Sciences, University of California, One Shields Avenue, Davis, California, 95616, USA
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36
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Microbe-microbe interactions trigger Mn(II)-oxidizing gene expression. ISME JOURNAL 2016; 11:67-77. [PMID: 27518809 DOI: 10.1038/ismej.2016.106] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 06/16/2016] [Accepted: 06/20/2016] [Indexed: 11/08/2022]
Abstract
Manganese (Mn) is an important metal in geochemical cycles. Some microorganisms can oxidize Mn(II) to Mn oxides, which can, in turn, affect the global cycles of other elements by strong sorption and oxidation effects. Microbe-microbe interactions have important roles in a number of biological processes. However, how microbial interactions affect Mn(II) oxidation still remains unknown. Here, we investigated the interactions between two bacteria (Arthrobacter sp. and Sphingopyxis sp.) in a co-culture, which exhibited Mn(II)-oxidizing activity, although neither were able to oxidize Mn(II) in isolation. We demonstrated that the Mn(II)-oxidizing activity in co-culture was most likely induced via contact-dependent interactions. The expressed Mn(II)-oxidizing protein in the co-culture was purified and identified as a bilirubin oxidase belonging to strain Arthrobacter. Full sequencing of the bilirubin oxidase-encoding gene (boxA) was performed. The Mn(II)-oxidizing protein and the transcripts of boxA were detected in the co-culture, but not in either of the isolated cultures. This indicate that boxA was silent in Arthrobacter monoculture, and was activated in response to presence of Sphingopyxis in the co-culture. Further, transcriptomic analysis by RNA-Seq, extracellular superoxide detection and cell density quantification by flow cytometry indicate induction of boxA gene expression in Arthrobacter was co-incident with a stress response triggered by co-cultivation with Sphingopyxis. Our findings suggest the potential roles of microbial physiological responses to stress induced by other microbes in Mn(II) oxidation and extracellular superoxide production.
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Identification of a Third Mn(II) Oxidase Enzyme in Pseudomonas putida GB-1. Appl Environ Microbiol 2016; 82:3774-3782. [PMID: 27084014 DOI: 10.1128/aem.00046-16] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 04/12/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The oxidation of soluble Mn(II) to insoluble Mn(IV) is a widespread bacterial activity found in a diverse array of microbes. In the Mn(II)-oxidizing bacterium Pseudomonas putida GB-1, two Mn(II) oxidase genes, named mnxG and mcoA, were previously identified; each encodes a multicopper oxidase (MCO)-type enzyme. Expression of these two genes is positively regulated by the response regulator MnxR. Preliminary investigation into putative additional regulatory pathways suggested that the flagellar regulators FleN and FleQ also regulate Mn(II) oxidase activity; however, it also revealed the presence of a third, previously uncharacterized Mn(II) oxidase activity in P. putida GB-1. A strain from which both of the Mn(II) oxidase genes and fleQ were deleted exhibited low levels of Mn(II) oxidase activity. The enzyme responsible was genetically and biochemically identified as an animal heme peroxidase (AHP) with domain and sequence similarity to the previously identified Mn(II) oxidase MopA. In the ΔfleQ strain, P. putida GB-1 MopA is overexpressed and secreted from the cell, where it actively oxidizes Mn. Thus, deletion of fleQ unmasked a third Mn(II) oxidase activity in this strain. These results provide an example of an Mn(II)-oxidizing bacterium utilizing both MCO and AHP enzymes. IMPORTANCE The identity of the Mn(II) oxidase enzyme in Pseudomonas putida GB-1 has been a long-standing question in the field of bacterial Mn(II) oxidation. In the current work, we demonstrate that P. putida GB-1 employs both the multicopper oxidase- and animal heme peroxidase-mediated pathways for the oxidation of Mn(II), rendering this model organism relevant to the study of both types of Mn(II) oxidase enzymes. The presence of three oxidase enzymes in P. putida GB-1 deepens the mystery of why microorganisms oxidize Mn(II) while providing the field with the tools necessary to address this question. The initial identification of MopA as a Mn(II) oxidase in this strain required the deletion of FleQ, a regulator involved in both flagellum synthesis and biofilm synthesis in Pseudomonas aeruginosa Therefore, these results are also an important step toward understanding the regulation of Mn(II) oxidation.
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Recent progress in understanding the molecular mechanisms of radioresistance in Deinococcus bacteria. Extremophiles 2015; 19:707-19. [DOI: 10.1007/s00792-015-0759-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 05/17/2015] [Indexed: 12/17/2022]
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Learman DR, Hansel CM. Comparative proteomics of Mn(II)-oxidizing and non-oxidizing Roseobacter clade bacteria reveal an operative manganese transport system but minimal Mn(II)-induced expression of manganese oxidation and antioxidant enzymes. ENVIRONMENTAL MICROBIOLOGY REPORTS 2014; 6:501-509. [PMID: 25646543 DOI: 10.1111/1758-2229.12164] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Manganese (Mn) is an essential nutrient and precipitates as minerals with technological and environmental relevance. To gain a proteomic understanding of how bacteria respond to Mn(II) and its connection to oxidation, a comparative examination of the proteomic response of Mn(II)-oxidizing (Roseobacter sp. AzwK-3b) and non-oxidizing (Ruegeria sp. TM1040) alphaproteobacteria was conducted. Both bacteria show an operative Mn(II) transport system. In the absence of Mn(II), both bacteria have higher expression of proteins that were homologous to SitA and SitB, known proteins in the Mn(II) transport system of other alphaproteobacteria. Overall, each bacterium demonstrated a varied response to Mn(II). Ru. TM1040 had a greater number of proteins differentially expressed in response to Mn(II) and also had a group of proteins related to chemotaxis at higher concentrations of Mn(II), suggesting a potential stress response. While both bacteria are able to generate extracellular superoxide and Mn(II) is a known antioxidant, the presence of Mn(II) did not significantly alter the expression of proteins related to antioxidant activity. Heme peroxidases, previously connected to Mn(II) oxidation, were found in the soluble protein extract of R. AzwK-3b, but only minor differential expression was observed as a function of Mn(II), indicating that their expression was not induced by Mn(II).
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A Mur regulator protein in the extremophilic bacterium Deinococcus radiodurans. PLoS One 2014; 9:e106341. [PMID: 25243898 PMCID: PMC4171365 DOI: 10.1371/journal.pone.0106341] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 07/29/2014] [Indexed: 12/11/2022] Open
Abstract
Ferric uptake regulator (Fur) is a transcriptional regulator that controls the expression of genes involved in the uptake of iron and manganese, as well as vital nutrients, and is essential for intracellular redox cycling. We identified a unique Fur homolog (DR0865) from Deinococcus radiodurans, which is known for its extreme resistance to radiation and oxidants. A dr0865 mutant (Mt-0865) showed a higher sensitivity to manganese stress, hydrogen peroxide, gamma irradiation and ultraviolet (UV) irradiation than the wild-type R1 strain. Cellular manganese (Mn) ion (Mn2+) analysis showed that Mn2+, copper (Cu2+), and ferric (Fe3+) ions accumulated significantly in the mutant, which suggests that the dr0865 gene is not only involved in the regulation of Mn2+ homeostasis, but also affects the uptake of other ions. In addition, transcriptome profiles under MnCl2 stress showed that the expression of many genes involved in Mn metabolism was significantly different in the wild-type R1 and DR0865 mutant (Mt-0865). Furthermore, we found that the dr0865 gene serves as a positive regulator of the manganese efflux pump gene mntE (dr1236), and as a negative regulator of Mn ABC transporter genes, such as dr2283, dr2284 and dr2523. Therefore, it plays an important role in maintaining the homoeostasis of intracellular Mn (II), and also other Mn2+, zinc (Zn2+) and Cu2+ ions. Based on its role in manganese homeostasis, DR0865 likely belongs to the Mur sub-family of Fur homolog.
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Kim J, Park W. Oxidative stress response in Pseudomonas putida. Appl Microbiol Biotechnol 2014; 98:6933-46. [PMID: 24957251 DOI: 10.1007/s00253-014-5883-4] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 06/04/2014] [Accepted: 06/05/2014] [Indexed: 11/30/2022]
Abstract
Pseudomonas putida is widely distributed in nature and is capable of degrading various organic compounds due to its high metabolic versatility. The survival capacity of P. putida stems from its frequent exposure to various endogenous and exogenous oxidative stresses. Oxidative stress is an unavoidable consequence of interactions with various reactive oxygen species (ROS)-inducing agents existing in various niches. ROS could facilitate the evolution of bacteria by mutating genomes. Aerobic bacteria maintain defense mechanisms against oxidative stress throughout their evolution. To overcome the detrimental effects of oxidative stress, P. putida has developed defensive cellular systems involving induction of stress-sensing proteins and detoxification enzymes as well as regulation of oxidative stress response networks. Genetic responses to oxidative stress in P. putida differ markedly from those observed in Escherichia coli and Salmonella spp. Two major redox-sensing transcriptional regulators, SoxR and OxyR, are present and functional in the genome of P. putida. However, the novel regulators FinR and HexR control many genes belonging to the E. coli SoxR regulon. Oxidative stress can be generated by exposure to antibiotics, and iron homeostasis in P. putida is crucial for bacterial cell survival during treatment with antibiotics. This review highlights and summarizes current knowledge of oxidative stress in P. putida, as a model soil bacterium, together with recent studies from molecular genetics perspectives.
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Affiliation(s)
- Jisun Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Anam-Dong 5Ga, Seungbuk-Ku, Seoul, 136-713, Republic of Korea
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Identification of Mn(II)-oxidizing bacteria from a low-pH contaminated former uranium mine. Appl Environ Microbiol 2014; 80:5086-97. [PMID: 24928873 DOI: 10.1128/aem.01296-14] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Biological Mn oxidation is responsible for producing highly reactive and abundant Mn oxide phases in the environment that can mitigate metal contamination. However, little is known about Mn oxidation in low-pH environments, where metal contamination often is a problem as the result of mining activities. We isolated two Mn(II)-oxidizing bacteria (MOB) at pH 5.5 (Duganella isolate AB_14 and Albidiferax isolate TB-2) and nine strains at pH 7 from a former uranium mining site. Isolate TB-2 may contribute to Mn oxidation in the acidic Mn-rich subsoil, as a closely related clone represented 16% of the total community. All isolates oxidized Mn over a small pH range, and isolates from low-pH samples only oxidized Mn below pH 6. Two strains with different pH optima differed in their Fe requirements for Mn oxidation, suggesting that Mn oxidation by the strain found at neutral pH was linked to Fe oxidation. Isolates tolerated Ni, Cu, and Cd and produced Mn oxides with similarities to todorokite and birnessite, with the latter being present in subsurface layers where metal enrichment was associated with Mn oxides. This demonstrates that MOB can be involved in the formation of biogenic Mn oxides in both moderately acidic and neutral pH environments.
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