1
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Schneider H, Lai B, Krömer J. Utilizing Cyanobacteria in Biophotovoltaics: An Emerging Field in Bioelectrochemistry. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2023; 183:281-302. [PMID: 36441187 DOI: 10.1007/10_2022_212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Anthropogenic global warming is driven by the increasing energy demand and the still dominant use of fossil energy carriers to meet these needs. New carbon-neutral energy sources are urgently needed to solve this problem. Biophotovoltaics, a member of the so-called bioelectrochemical systems family, will provide an important piece of the energy puzzle. It aims to harvest the electrons from sunlight-driven water splitting using the natural oxygenic photosystem (e.g., of cyanobacteria) and utilize them in the form of, e.g., electricity or hydrogen. Several key aspects of biophotovoltaics have been intensively studied in recent years like physicochemical properties of electrodes or efficient wiring of microorganisms to electrodes. Yet, the exact mechanisms of electron transfer between the biocatalyst and the electrode remain unresolved today. Most research is conducted on microscale reactors generating small currents over short time-scales, but multiple experiments have shown biophotovoltaics great potential with lab-scale reactors producing currents over weeks to months. Although biophotovoltaics is still in its infancy with many open research questions to be addressed, new promising results from various labs around the world suggest an important opportunity for biophotovoltaics in the decades to come. In this chapter, we will introduce the concept of biophotovoltaics, summarize its recent key progress, and finally critically discuss the potentials and challenges for future rational development of biophotovoltaics.
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Affiliation(s)
- Hans Schneider
- Department of Solar Materials, Helmholtz Center for Environmental Research, Leipzig, Germany.
| | - Bin Lai
- Department of Solar Materials, Helmholtz Center for Environmental Research, Leipzig, Germany
| | - Jens Krömer
- Department of Solar Materials, Helmholtz Center for Environmental Research, Leipzig, Germany
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2
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Elucidation of the coping strategy in an OMP homozygous knockout mutant of Synechocystis 6803 defective in iron uptake. Arch Microbiol 2022; 204:358. [DOI: 10.1007/s00203-022-02968-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 04/18/2022] [Accepted: 05/09/2022] [Indexed: 11/02/2022]
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3
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Ansari AA, Ansari AA, Abouhend AS, Gikonyo JG, Park C. Photogranulation in a Hydrostatic Environment Occurs with Limitation of Iron. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:10672-10683. [PMID: 34255495 DOI: 10.1021/acs.est.0c07374] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Filamentous cyanobacteria are an essential element of oxygenic photogranules for granule-based wastewater treatment with photosynthetic aeration. Currently, mechanisms for the selection of this microbial group and their development in the granular structure are not well understood. Here, we studied the characteristics and fate of iron in photogranulation that proceeds in a hydrostatic environment with an activated sludge (AS) inoculum. We found that the level of Fe in bulk liquids (FeBL) sharply increased due to the decay of the inoculum but quickly diminished along with the bloom of microalgae and the advent of the oxic environment. Iron linked with extracellular polymeric substances (FeEPS) continued to decline but reached steady low values, which occurred along with the appearance of granular structure. Strong negative correlations were found between FeEPS and the pigments specific for cyanobacteria. Spectroscopies revealed the presence of amorphous ferric oxides in pellet biomass, which seemed to remain unaltered during the photogranulation process. These results suggest that the availability of FeEPS in AS inoculums-after algal bloom-selects cyanobacteria, and the limitation of this Fe pool becomes an important driver for cyanobacteria to granulate in a hydrostatic environment. We therefore propose that the availability of iron has a strong influence on the photogranulation process.
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Affiliation(s)
- Abeera A Ansari
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
- U.S.-Pakistan Center for Advanced Studies in Energy (USPCAS-E), National University of Sciences and Technology (NUST), H-12 Sector, 44000 Islamabad , Pakistan
| | - Arfa A Ansari
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
| | - Ahmed S Abouhend
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
| | - Joseph G Gikonyo
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
| | - Chul Park
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
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4
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Hashemi S, Hashemi SE, Lien KM, Lamb JJ. Molecular Microbial Community Analysis as an Analysis Tool for Optimal Biogas Production. Microorganisms 2021; 9:microorganisms9061162. [PMID: 34071282 PMCID: PMC8226781 DOI: 10.3390/microorganisms9061162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/17/2021] [Accepted: 05/26/2021] [Indexed: 11/16/2022] Open
Abstract
The microbial diversity in anaerobic digestion (AD) is important because it affects process robustness. High-throughput sequencing offers high-resolution data regarding the microbial diversity and robustness of biological systems including AD; however, to understand the dynamics of microbial processes, knowing the microbial diversity is not adequate alone. Advanced meta-omic techniques have been established to determine the activity and interactions among organisms in biological processes like AD. Results of these methods can be used to identify biomarkers for AD states. This can aid a better understanding of system dynamics and be applied to producing comprehensive models for AD. The paper provides valuable knowledge regarding the possibility of integration of molecular methods in AD. Although meta-genomic methods are not suitable for on-line use due to long operating time and high costs, they provide extensive insight into the microbial phylogeny in AD. Meta-proteomics can also be explored in the demonstration projects for failure prediction. However, for these methods to be fully realised in AD, a biomarker database needs to be developed.
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Affiliation(s)
- Seyedbehnam Hashemi
- Department of Energy and Process Engineering & Enersense, Norwegian University of Science and Technology (NTNU), 7034 Trondheim, Norway; (S.H.); (S.E.H.); (K.M.L.)
| | - Sayed Ebrahim Hashemi
- Department of Energy and Process Engineering & Enersense, Norwegian University of Science and Technology (NTNU), 7034 Trondheim, Norway; (S.H.); (S.E.H.); (K.M.L.)
| | - Kristian M. Lien
- Department of Energy and Process Engineering & Enersense, Norwegian University of Science and Technology (NTNU), 7034 Trondheim, Norway; (S.H.); (S.E.H.); (K.M.L.)
| | - Jacob J. Lamb
- Department of Energy and Process Engineering & Enersense, Norwegian University of Science and Technology (NTNU), 7034 Trondheim, Norway; (S.H.); (S.E.H.); (K.M.L.)
- Department of Electronic Systems, Norwegian University of Science and Technology (NTNU), 7034 Trondheim, Norway
- Correspondence:
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5
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Jeong Y, Hong SJ, Cho SH, Yoon S, Lee H, Choi HK, Kim DM, Lee CG, Cho S, Cho BK. Multi-Omic Analyses Reveal Habitat Adaptation of Marine Cyanobacterium Synechocystis sp. PCC 7338. Front Microbiol 2021; 12:667450. [PMID: 34054774 PMCID: PMC8155712 DOI: 10.3389/fmicb.2021.667450] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 04/19/2021] [Indexed: 11/13/2022] Open
Abstract
Cyanobacteria are considered as promising microbial cell factories producing a wide array of bio-products. Among them, Synechocystis sp. PCC 7338 has the advantage of growing in seawater, rather than requiring arable land or freshwater. Nonetheless, how this marine cyanobacterium grows under the high salt stress condition remains unknown. Here, we determined its complete genome sequence with the embedded regulatory elements and analyzed the transcriptional changes in response to a high-salt environment. Complete genome sequencing revealed a 3.70 mega base pair genome and three plasmids with a total of 3,589 genes annotated. Differential RNA-seq and Term-seq data aligned to the complete genome provided genome-wide information on genetic regulatory elements, including promoters, ribosome-binding sites, 5'- and 3'-untranslated regions, and terminators. Comparison with freshwater Synechocystis species revealed Synechocystis sp. PCC 7338 genome encodes additional genes, whose functions are related to ion channels to facilitate the adaptation to high salt and high osmotic pressure. Furthermore, a ferric uptake regulator binding motif was found in regulatory regions of various genes including SigF and the genes involved in energy metabolism, suggesting the iron-regulatory network is connected to not only the iron acquisition, but also response to high salt stress and photosynthesis. In addition, the transcriptomics analysis demonstrated a cyclic electron transport through photosystem I was actively used by the strain to satisfy the demand for ATP under high-salt environment. Our comprehensive analyses provide pivotal information to elucidate the genomic functions and regulations in Synechocystis sp. PCC 7338.
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Affiliation(s)
- Yujin Jeong
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Seong-Joo Hong
- Department of Biological Engineering, Inha University, Incheon, South Korea.,Department of Biological Sciences and Bioengineering, Inha University, Incheon, South Korea
| | - Sang-Hyeok Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Seonghoon Yoon
- Department of Biological Engineering, Inha University, Incheon, South Korea.,Department of Biological Sciences and Bioengineering, Inha University, Incheon, South Korea
| | - Hookeun Lee
- Institute of Pharmaceutical Research, College of Pharmacy, Gachon University, Incheon, South Korea
| | | | - Dong-Myung Kim
- Department of Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon, South Korea
| | - Choul-Gyun Lee
- Department of Biological Engineering, Inha University, Incheon, South Korea.,Department of Biological Sciences and Bioengineering, Inha University, Incheon, South Korea
| | - Suhyung Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,Innovative Biomaterials Center, KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,Innovative Biomaterials Center, KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,Intelligent Synthetic Biology Center, Daejeon, South Korea
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6
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Tanaka K, Shimakawa G, Kusama S, Harada T, Kato S, Nakanishi S. Ferrihydrite Reduction by Photosynthetic Synechocystis sp. PCC 6803 and Its Correlation With Electricity Generation. Front Microbiol 2021; 12:650832. [PMID: 33763051 PMCID: PMC7982531 DOI: 10.3389/fmicb.2021.650832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 02/16/2021] [Indexed: 11/29/2022] Open
Abstract
Microbial extracellular electron transfer (EET) to solid-state electron acceptors such as anodes and metal oxides, which was originally identified in dissimilatory metal-reducing bacteria, is a key process in microbial electricity generation and the biogeochemical cycling of metals. Although it is now known that photosynthetic microorganisms can also generate (photo)currents via EET, which has attracted much interest in the field of biophotovoltaics, little is known about the reduction of metal (hydr)oxides via photosynthetic microbial EET. The present work quantitatively assessed the reduction of ferrihydrite in conjunction with the EET of the photosynthetic microbe Synechocystis sp. PCC 6803. Microbial reduction of ferrihydrite was found to be initiated in response to light but proceeded at higher rates when exogenous glucose was added, even under dark conditions. These results indicate that current generation from Synechocystis cells does not always need light irradiation. The qualitative trends exhibited by the ferrihydrite reduction rates under various conditions showed significant correlation with those of the microbial currents. Notably, the maximum concentration of Fe(II) generated by the cyanobacterial cells under dark conditions in the presence of glucose was comparable to the levels observed in the photic layers of Fe-rich microbial mats.
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Affiliation(s)
- Kenya Tanaka
- Graduate School of Engineering Science, Osaka University, Toyonaka, Japan
| | - Ginga Shimakawa
- Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
| | - Shoko Kusama
- Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
| | - Takashi Harada
- Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
| | - Souichiro Kato
- Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan.,Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Sapporo, Japan
| | - Shuji Nakanishi
- Graduate School of Engineering Science, Osaka University, Toyonaka, Japan.,Research Center for Solar Energy Chemistry, Osaka University, Toyonaka, Japan
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7
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Hunnestad AV, Vogel AIM, Armstrong E, Digernes MG, Ardelan MV, Hohmann-Marriott MF. From the Ocean to the Lab-Assessing Iron Limitation in Cyanobacteria: An Interface Paper. Microorganisms 2020; 8:E1889. [PMID: 33260337 PMCID: PMC7760322 DOI: 10.3390/microorganisms8121889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/25/2020] [Accepted: 11/26/2020] [Indexed: 12/22/2022] Open
Abstract
Iron is an essential, yet scarce, nutrient in marine environments. Phytoplankton, and especially cyanobacteria, have developed a wide range of mechanisms to acquire iron and maintain their iron-rich photosynthetic machinery. Iron limitation studies often utilize either oceanographic methods to understand large scale processes, or laboratory-based, molecular experiments to identify underlying molecular mechanisms on a cellular level. Here, we aim to highlight the benefits of both approaches to encourage interdisciplinary understanding of the effects of iron limitation on cyanobacteria with a focus on avoiding pitfalls in the initial phases of collaboration. In particular, we discuss the use of trace metal clean methods in combination with sterile techniques, and the challenges faced when a new collaboration is set up to combine interdisciplinary techniques. Methods necessary for producing reliable data, such as High Resolution Inductively Coupled Plasma Mass Spectrometry (HR-ICP-MS), Flow Injection Analysis Chemiluminescence (FIA-CL), and 77K fluorescence emission spectroscopy are discussed and evaluated and a technical manual, including the preparation of the artificial seawater medium Aquil, cleaning procedures, and a sampling scheme for an iron limitation experiment is included. This paper provides a reference point for researchers to implement different techniques into interdisciplinary iron studies that span cyanobacteria physiology, molecular biology, and biogeochemistry.
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Affiliation(s)
- Annie Vera Hunnestad
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.V.H.); (M.G.D.)
| | - Anne Ilse Maria Vogel
- PhotoSynLab, Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.I.M.V.); (M.F.H.-M.)
| | - Evelyn Armstrong
- NIWA/University of Otago Research Centre for Oceanography, Department of Chemistry, University of Otago, 9054 Dunedin, New Zealand;
| | - Maria Guadalupe Digernes
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.V.H.); (M.G.D.)
| | - Murat Van Ardelan
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.V.H.); (M.G.D.)
| | - Martin Frank Hohmann-Marriott
- PhotoSynLab, Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.I.M.V.); (M.F.H.-M.)
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8
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Schirmacher AM, Hanamghar SS, Zedler JAZ. Function and Benefits of Natural Competence in Cyanobacteria: From Ecology to Targeted Manipulation. Life (Basel) 2020; 10:E249. [PMID: 33105681 PMCID: PMC7690421 DOI: 10.3390/life10110249] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 10/18/2020] [Accepted: 10/20/2020] [Indexed: 02/03/2023] Open
Abstract
Natural competence is the ability of a cell to actively take up and incorporate foreign DNA in its own genome. This trait is widespread and ecologically significant within the prokaryotic kingdom. Here we look at natural competence in cyanobacteria, a group of globally distributed oxygenic photosynthetic bacteria. Many cyanobacterial species appear to have the genetic potential to be naturally competent, however, this ability has only been demonstrated in a few species. Reasons for this might be due to a high variety of largely uncharacterised competence inducers and a lack of understanding the ecological context of natural competence in cyanobacteria. To shed light on these questions, we describe what is known about the molecular mechanisms of natural competence in cyanobacteria and analyse how widespread this trait might be based on available genomic datasets. Potential regulators of natural competence and what benefits or drawbacks may derive from taking up foreign DNA are discussed. Overall, many unknowns about natural competence in cyanobacteria remain to be unravelled. A better understanding of underlying mechanisms and how to manipulate these, can aid the implementation of cyanobacteria as sustainable production chassis.
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Affiliation(s)
| | | | - Julie A. Z. Zedler
- Matthias Schleiden Institute for Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, 07743 Jena, Germany; (A.M.S.); (S.S.H.)
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9
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Russo DA, Zedler JAZ. Genomic insights into cyanobacterial protein translocation systems. Biol Chem 2020; 402:39-54. [PMID: 33544489 DOI: 10.1515/hsz-2020-0247] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 09/25/2020] [Indexed: 02/07/2023]
Abstract
Cyanobacteria are ubiquitous oxygenic photosynthetic bacteria with a versatile metabolism that is highly dependent on effective protein targeting. Protein sorting in diderm bacteria is not trivial and, in cyanobacteria, even less so due to the presence of a complex membrane system: the outer membrane, the plasma membrane and the thylakoid membrane. In cyanobacteria, protein import into the thylakoids is essential for photosynthesis, export to the periplasm fulfills a multifunctional role in maintaining cell homeostasis, and secretion mediates motility, DNA uptake and environmental interactions. Intriguingly, only one set of genes for the general secretory and the twin-arginine translocation pathways seem to be present. However, these systems have to operate in both plasma and thylakoid membranes. This raises the question of how substrates are recognized and targeted to their correct, final destination. Additional complexities arise when a protein has to be secreted across the outer membrane, where very little is known regarding the mechanisms involved. Given their ecological importance and biotechnological interest, a better understanding of protein targeting in cyanobacteria is of great value. This review will provide insights into the known knowns of protein targeting, propose hypotheses based on available genomic sequences and discuss future directions.
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Affiliation(s)
- David A Russo
- Bioorganic Analytics, Institute for Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, D-07743 Jena, Germany
| | - Julie A Z Zedler
- Matthias Schleiden Institute for Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, Dornburgerstr. 159, D-07743 Jena, Germany
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10
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Thirumurthy MA, Hitchcock A, Cereda A, Liu J, Chavez MS, Doss BL, Ros R, El-Naggar MY, Heap JT, Bibby TS, Jones AK. Type IV Pili-Independent Photocurrent Production by the Cyanobacterium Synechocystis sp. PCC 6803. Front Microbiol 2020; 11:1344. [PMID: 32714295 PMCID: PMC7344198 DOI: 10.3389/fmicb.2020.01344] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/26/2020] [Indexed: 11/13/2022] Open
Abstract
Biophotovoltaic devices utilize photosynthetic organisms such as the model cyanobacterium Synechocystis sp. PCC 6803 (Synechocystis) to generate current for power or hydrogen production from light. These devices have been improved by both architecture engineering and genetic engineering of the phototrophic organism. However, genetic approaches are limited by lack of understanding of cellular mechanisms of electron transfer from internal metabolism to the cell exterior. Type IV pili have been implicated in extracellular electron transfer (EET) in some species of heterotrophic bacteria. Furthermore, conductive cell surface filaments have been reported for cyanobacteria, including Synechocystis. However, it remains unclear whether these filaments are type IV pili and whether they are involved in EET. Herein, a mediatorless electrochemical setup is used to compare the electrogenic output of wild-type Synechocystis to that of a ΔpilD mutant that cannot produce type IV pili. No differences in photocurrent, i.e., current in response to illumination, are detectable. Furthermore, measurements of individual pili using conductive atomic force microscopy indicate these structures are not conductive. These results suggest that pili are not required for EET by Synechocystis, supporting a role for shuttling of electrons via soluble redox mediators or direct interactions between the cell surface and extracellular substrates.
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Affiliation(s)
| | - Andrew Hitchcock
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, United Kingdom
| | - Angelo Cereda
- School of Molecular Sciences, Arizona State University, Tempe, AZ, United States
| | - Jiawei Liu
- Department of Physics, Arizona State University, Tempe, AZ, United States
| | - Marko S. Chavez
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, United States
| | - Bryant L. Doss
- Department of Physics, Arizona State University, Tempe, AZ, United States
| | - Robert Ros
- Department of Physics, Arizona State University, Tempe, AZ, United States
| | - Mohamed Y. El-Naggar
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, United States
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
- Department of Chemistry, University of Southern California, Los Angeles, CA, United States
| | - John T. Heap
- Imperial College Centre for Synthetic Biology, Department of Life Sciences, Imperial College London, London, United Kingdom
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Thomas S. Bibby
- Ocean and Earth Science, University of Southampton, Southampton, United Kingdom
| | - Anne K. Jones
- School of Molecular Sciences, Arizona State University, Tempe, AZ, United States
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11
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Chen Z, Li X, Tan X, Zhang Y, Wang B. Recent Advances in Biological Functions of Thick Pili in the Cyanobacterium Synechocystis sp. PCC 6803. FRONTIERS IN PLANT SCIENCE 2020; 11:241. [PMID: 32210999 PMCID: PMC7076178 DOI: 10.3389/fpls.2020.00241] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 02/17/2020] [Indexed: 05/05/2023]
Abstract
Cyanobacteria have evolved various strategies to sense and adapt to biotic and abiotic stresses including active movement. Motility in cyanobacteria utilizing the type IV pili (TFP) is useful to cope with changing environmental conditions. The model cyanobacterium Synechocystis sp. PCC 6803 (hereafter named Synechocystis) exhibits motility via TFP called thick pili, and uses it to seek out favorable light/nutrition or escape from unfavorable conditions. Recently, a number of studies on Synechocystis thick pili have been undertaken. Molecular approaches support the role of the pilin in motility, cell adhesion, metal utilization, and natural competence in Synechocystis. This review summarizes the most recent studies on the function of thick pili as well as their formation and regulation in this cyanobacterium.
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Affiliation(s)
- Zhuo Chen
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan, China
| | - Xitong Li
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan, China
| | - Xiaoming Tan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Yan Zhang
- Biotechnology Research Center, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Baoshan Wang
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan, China
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12
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Abstract
A merged system incorporating paperfluidics and papertronics has recently emerged as a simple, single-use, low-cost paradigm for disposable point-of-care (POC) diagnostic applications. Stand-alone and self-sustained paper-based systems are essential to providing effective and lifesaving treatments in resource-constrained environments. Therefore, a realistic and accessible power source is required for actual paper-based POC systems as their diagnostic performance and portability rely significantly on power availability. Among many paper-based batteries and energy storage devices, paper-based microbial fuel cells have attracted much attention because bacteria can harvest electricity from any type of organic matter that is readily available in those challenging regions. However, the promise of this technology has not been translated into practical power applications because of its short power duration, which is not enough to fully operate those systems for a relatively long period. In this work, we for the first time demonstrate a simple and long-lasting paper-based biological solar cell that uses photosynthetic bacteria as biocatalysts. The bacterial photosynthesis and respiration continuously and self-sustainably generate power by converting light energy into electricity. With a highly porous and conductive anode and an innovative solid-state cathode, the biological solar cell built upon the paper substrates generated the maximum current and power density of 65 µA/cm2 and 10.7 µW/cm2, respectively, which are considerably greater than those of conventional micro-sized biological solar cells. Furthermore, photosynthetic bacteria in a 3-D volumetric chamber made of a stack of papers provided stable and long-lasting electricity for more than 5 h, while electrical current from the heterotrophic culture on 2-D paper dramatically decreased within several minutes.
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Affiliation(s)
- Lin Liu
- Bioelectronics & Microsystems Laboratory, Department of Electrical & Computer Engineering, State University of New York at Binghamton, Binghamton, NY, USA
| | - Seokheun Choi
- Bioelectronics & Microsystems Laboratory, Department of Electrical & Computer Engineering, State University of New York at Binghamton, Binghamton, NY, USA
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13
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Årstøl E, Hohmann-Marriott MF. Cyanobacterial Siderophores-Physiology, Structure, Biosynthesis, and Applications. Mar Drugs 2019; 17:E281. [PMID: 31083354 PMCID: PMC6562677 DOI: 10.3390/md17050281] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/06/2019] [Accepted: 05/07/2019] [Indexed: 11/16/2022] Open
Abstract
Siderophores are low-molecular-weight metal chelators that function in microbial iron uptake. As iron limits primary productivity in many environments, siderophores are of great ecological importance. Additionally, their metal binding properties have attracted interest for uses in medicine and bioremediation. Here, we review the current state of knowledge concerning the siderophores produced by cyanobacteria. We give an overview of all cyanobacterial species with known siderophore production, finding siderophores produced in all but the most basal clades, and in a wide variety of environments. We explore what is known about the structure, biosynthesis, and cycling of the cyanobacterial siderophores that have been characterized: Synechobactin, schizokinen and anachelin. We also highlight alternative siderophore functionality and technological potential, finding allelopathic effects on competing phytoplankton and likely roles in limiting heavy-metal toxicity. Methodological improvements in siderophore characterization and detection are briefly described. Since most known cyanobacterial siderophores have not been structurally characterized, the application of mass spectrometry techniques will likely reveal a breadth of variation within these important molecules.
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Affiliation(s)
- Erland Årstøl
- Department of Biotechnology, PhotoSynLab, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| | - Martin F Hohmann-Marriott
- Department of Biotechnology, PhotoSynLab, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
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14
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Polyviou D, Baylay AJ, Hitchcock A, Robidart J, Moore CM, Bibby TS. Desert Dust as a Source of Iron to the Globally Important Diazotroph Trichodesmium. Front Microbiol 2018; 8:2683. [PMID: 29387046 PMCID: PMC5776111 DOI: 10.3389/fmicb.2017.02683] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 12/22/2017] [Indexed: 12/22/2022] Open
Abstract
The marine cyanobacterium Trichodesmium sp. accounts for approximately half of the annual ‘new’ nitrogen introduced to the global ocean but its biogeography and activity is often limited by the availability of iron (Fe). A major source of Fe to the open ocean is Aeolian dust deposition in which Fe is largely comprised of particles with reduced bioavailability over soluble forms of Fe. We report that Trichodesmium erythraeum IMS101 has improved growth rate and photosynthetic physiology and down-regulates Fe-stress biomarker genes when cells are grown in the direct vicinity of, rather than physically separated from, Saharan dust particles as the sole source of Fe. These findings suggest that availability of non-soluble forms of dust-associated Fe may depend on cell contact. Transcriptomic analysis further reveals unique profiles of gene expression in all tested conditions, implying that Trichodesmium has distinct molecular signatures related to acquisition of Fe from different sources. Trichodesmium thus appears to be capable of employing specific mechanisms to access Fe from complex sources in oceanic systems, helping to explain its role as a key microbe in global biogeochemical cycles.
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Affiliation(s)
- Despo Polyviou
- Ocean and Earth Science, University of Southampton, Waterfront Campus, Southampton, United Kingdom
| | - Alison J Baylay
- Ocean and Earth Science, University of Southampton, Waterfront Campus, Southampton, United Kingdom
| | - Andrew Hitchcock
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Sheffield, United Kingdom
| | - Julie Robidart
- Ocean Technology and Engineering Group, National Oceanography Centre, Southampton, United Kingdom
| | - C M Moore
- Ocean and Earth Science, University of Southampton, Waterfront Campus, Southampton, United Kingdom
| | - Thomas S Bibby
- Ocean and Earth Science, University of Southampton, Waterfront Campus, Southampton, United Kingdom
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15
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Gonzalez-Aravena AC, Yunus K, Zhang L, Norling B, Fisher AC. Tapping into cyanobacteria electron transfer for higher exoelectrogenic activity by imposing iron limited growth. RSC Adv 2018; 8:20263-20274. [PMID: 35541668 PMCID: PMC9080828 DOI: 10.1039/c8ra00951a] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 05/14/2018] [Indexed: 11/21/2022] Open
Abstract
The exoelectrogenic capacity of the cyanobacterium Synechococcus elongatus PCC7942 was studied in iron limited growth in order to establish conditions favouring extracellular electron transfer in cyanobacteria for photo-bioelectricity generation. Investigation into extracellular reduction of ferricyanide by Synechococcus elongatus PCC7942 demonstrated enhanced capability for the iron limited conditions in comparison to the iron sufficient conditions. Furtheremore, the significance of pH showed that higher rates of ferricyanide reduction occurred at pH 7, with a 2.7-fold increase with respect to pH 9.5 for iron sufficient cultures and 24-fold increase for iron limited cultures. The strategy presented induced exoelectrogenesis driven mainly by photosynthesis and an estimated redirection of the 28% of electrons from photosynthetic activity was achieved by the iron limited conditions. In addition, ferricyanide reduction in the dark by iron limited cultures also presented a significant improvement, with a 6-fold increase in comparison to iron sufficient cultures. Synechococcus elongatus PCC7942 ferricyanide reduction rates are unprecedented for cyanobacteria and they are comparable to those of microalgae. The redox activity of biofilms directly on ITO-coated glass, in the absence of any artificial mediator, was also enhanced under the iron limited conditions, implying that iron limitation increased exoelectrogenesis at the outer membrane level. Cyclic voltammetry of Synechococcus elongatus PCC7942 biofilms on ITO-coated glass showed a midpoint potential around 0.22 V vs. Ag/AgCl and iron limited biofilms had the capability to sustain currents in a saturated-like fashion. The present work proposes an iron related exoelectrogenic capacity of Synechococcus elongatus PCC7942 and sets a starting point for the study of this strain in order to improve photo-bioelectricity and dark-bioelectricity generation by cyanobacteria, including more sustainable mediatorless systems. Iron limited growth induces unprecedented rates of extracellular electron transport in cyanobacteria delivering enhanced photosynthesis driven bioelectricity in electrochemical platforms.![]()
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Affiliation(s)
| | - K. Yunus
- Department of Chemical Engineering and Biotechnology
- University of Cambridge
- Cambridge
- UK
| | - L. Zhang
- School of Biological Sciences
- Nanyang Technological University
- Singapore
| | - B. Norling
- School of Biological Sciences
- Nanyang Technological University
- Singapore
| | - A. C. Fisher
- Department of Chemical Engineering and Biotechnology
- University of Cambridge
- Cambridge
- UK
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16
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Lamb JJ, Hohmann-Marriott MF. Manganese acquisition is facilitated by PilA in the cyanobacterium Synechocystis sp. PCC 6803. PLoS One 2017; 12:e0184685. [PMID: 29016622 PMCID: PMC5634550 DOI: 10.1371/journal.pone.0184685] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 08/29/2017] [Indexed: 01/26/2023] Open
Abstract
Manganese is an essential element required by cyanobacteria, as it is an essential part of the oxygen-evolving center of photosystem II. In the presence of atmospheric oxygen, manganese is present as manganese oxides, which have low solubility and consequently provide low bioavailability. It is unknown if cyanobacteria are able to utilize these manganese sources, and what mechanisms may be employed to do so. Recent evidence suggests that type IV pili in non-photosynthetic bacteria facilitate electron donation to extracellular electron acceptors, thereby enabling metal acquisition. Our present study investigates whether PilA1 (major pilin protein of type IV pili) enables the cyanobacterium Synechocystis PCC 6808 to access to Mn from manganese oxides. We present physiological and spectroscopic data, which indicate that the presence of PilA1 enhances the ability of cyanobacteria to grow on manganese oxides. These observations suggest a role of PilA1-containing pili in cyanobacterial manganese acquisition.
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Affiliation(s)
- Jacob J. Lamb
- Department of Biotechnology & PhotoSynLab, NTNU, Trondheim, Norway
- Department of Electronic Systems & ENERSENSE, NTNU, Trondheim, Norway
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17
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Esteves-Ferreira AA, Inaba M, Obata T, Fort A, Fleming GTA, Araújo WL, Fernie AR, Sulpice R. A Novel Mechanism, Linked to Cell Density, Largely Controls Cell Division in Synechocystis. PLANT PHYSIOLOGY 2017; 174:2166-2182. [PMID: 28646084 PMCID: PMC5543973 DOI: 10.1104/pp.17.00729] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 06/20/2017] [Indexed: 05/28/2023]
Abstract
Many studies have investigated the various genetic and environmental factors regulating cyanobacterial growth. Here, we investigated the growth and metabolism of Synechocystis sp. PCC 6803 under different nitrogen sources, light intensities, and CO2 concentrations. Cells grown on urea showed the highest growth rates. However, for all conditions tested, the daily growth rates in batch cultures decreased steadily over time, and stationary phase was obtained with similar cell densities. Unexpectedly, metabolic and physiological analyses showed that growth rates during log phase were not controlled primarily by the availability of photoassimilates. Further physiological investigations indicated that nutrient limitation, quorum sensing, light quality, and light intensity (self-shading) were not the main factors responsible for the decrease in the growth rate and the onset of the stationary phase. Moreover, cell division rates in fed-batch cultures were positively correlated with the dilution rates. Hence, not only light, CO2, and nutrients can affect growth but also a cell-cell interaction. Accordingly, we propose that cell-cell interaction may be a factor responsible for the gradual decrease of growth rates in batch cultures during log phase, culminating with the onset of stationary phase.
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Affiliation(s)
- Alberto A Esteves-Ferreira
- National University of Ireland-Galway, Plant Systems Biology Laboratory, Plant and AgriBiosciences Research Centre, School of Natural Sciences, Galway, Ireland
- CAPES Foundation, Ministry of Education of Brazil, Brasilia DF 70040 020, Brazil
| | - Masami Inaba
- National University of Ireland-Galway, Plant Systems Biology Laboratory, Plant and AgriBiosciences Research Centre, School of Natural Sciences, Galway, Ireland
| | - Toshihiro Obata
- Central Metabolism Laboratory, Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Max Planck Society, 14476 Potsdam-Golm, Germany
| | - Antoine Fort
- National University of Ireland-Galway, Genetics and Biotechnology Research Laboratory, Plant and AgriBiosciences Research Centre, School of Natural Sciences, Galway, Ireland
| | - Gerard T A Fleming
- National University of Ireland-Galway, Microbiology, School of Natural Sciences, Galway, Ireland
| | - Wagner L Araújo
- Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900 Vicosa, Minas Gerais, Brazil
| | - Alisdair R Fernie
- Central Metabolism Laboratory, Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Max Planck Society, 14476 Potsdam-Golm, Germany
| | - Ronan Sulpice
- National University of Ireland-Galway, Plant Systems Biology Laboratory, Plant and AgriBiosciences Research Centre, School of Natural Sciences, Galway, Ireland
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18
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Kranzler C, Kessler N, Keren N, Shaked Y. Enhanced ferrihydrite dissolution by a unicellular, planktonic cyanobacterium: a biological contribution to particulate iron bioavailability. Environ Microbiol 2016; 18:5101-5111. [DOI: 10.1111/1462-2920.13496] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 07/31/2016] [Accepted: 08/11/2016] [Indexed: 11/27/2022]
Affiliation(s)
- Chana Kranzler
- Department of Plant and Environmental Sciences; The Alexander Silberman Institute of Life Sciences, Edmond J. Safra Campus, Givat Ram, Hebrew University of Jerusalem; Jerusalem Israel
- Interuniversity Institute for Marine Sciences in Eilat; POB 469 Eilat 88103 Israel
| | - Nivi Kessler
- Interuniversity Institute for Marine Sciences in Eilat; POB 469 Eilat 88103 Israel
- The Freddy and Nadine Herrmann Institute of Earth Sciences, Edmond J. Safra Campus, Givat Ram, Hebrew University of Jerusalem; Jerusalem Israel
| | - Nir Keren
- Department of Plant and Environmental Sciences; The Alexander Silberman Institute of Life Sciences, Edmond J. Safra Campus, Givat Ram, Hebrew University of Jerusalem; Jerusalem Israel
| | - Yeala Shaked
- Interuniversity Institute for Marine Sciences in Eilat; POB 469 Eilat 88103 Israel
- The Freddy and Nadine Herrmann Institute of Earth Sciences, Edmond J. Safra Campus, Givat Ram, Hebrew University of Jerusalem; Jerusalem Israel
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19
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Sure S, Ackland ML, Gaur A, Gupta P, Adholeya A, Kochar M. Probing Synechocystis-Arsenic Interactions through Extracellular Nanowires. Front Microbiol 2016; 7:1134. [PMID: 27486454 PMCID: PMC4949250 DOI: 10.3389/fmicb.2016.01134] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 07/07/2016] [Indexed: 11/13/2022] Open
Abstract
Microbial nanowires (MNWs) can play an important role in the transformation and mobility of toxic metals/metalloids in environment. The potential role of MNWs in cell-arsenic (As) interactions has not been reported in microorganisms and thus we explored this interaction using Synechocystis PCC 6803 as a model system. The effect of half maximal inhibitory concentration (IC50) [~300 mM As (V) and ~4 mM As (III)] and non-inhibitory [4X lower than IC50, i.e., 75 mM As (V) and 1 mM As (III)] of As was studied on Synechocystis cells in relation to its effect on Chlorophyll (Chl) a, type IV pili (TFP)-As interaction and intracellular/extracellular presence of As. In silico analysis showed that subunit PilA1 of electrically conductive TFP, i.e., microbial nanowires of Synechocystis have putative binding sites for As. In agreement with in silico analysis, transmission electron microscopy analysis showed that As was deposited on Synechocystis nanowires at all tested concentrations. The potential of Synechocystis nanowires to immobilize As can be further enhanced and evaluated on a large scale and thus can be applied for bioremediation studies.
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Affiliation(s)
- Sandeep Sure
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
| | - M L Ackland
- Centre for Cellular & Molecular Biology, Deakin University, Melbourne VIC, Australia
| | - Aditya Gaur
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
| | - Priyanka Gupta
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
| | - Alok Adholeya
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
| | - Mandira Kochar
- TERI-Deakin Nano biotechnology Centre, The Energy and Resources Institute Gurgaon, India
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20
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Snow JT, Polyviou D, Skipp P, Chrismas NAM, Hitchcock A, Geider R, Moore CM, Bibby TS. Quantifying Integrated Proteomic Responses to Iron Stress in the Globally Important Marine Diazotroph Trichodesmium. PLoS One 2015; 10:e0142626. [PMID: 26562022 PMCID: PMC4642986 DOI: 10.1371/journal.pone.0142626] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 10/23/2015] [Indexed: 02/03/2023] Open
Abstract
Trichodesmium is a biogeochemically important marine cyanobacterium, responsible for a significant proportion of the annual 'new' nitrogen introduced into the global ocean. These non-heterocystous filamentous diazotrophs employ a potentially unique strategy of near-concurrent nitrogen fixation and oxygenic photosynthesis, potentially burdening Trichodesmium with a particularly high iron requirement due to the iron-binding proteins involved in these processes. Iron availability may therefore have a significant influence on the biogeography of Trichodesmium. Previous investigations of molecular responses to iron stress in this keystone marine microbe have largely been targeted. Here a holistic approach was taken using a label-free quantitative proteomics technique (MSE) to reveal a sophisticated multi-faceted proteomic response of Trichodesmium erythraeum IMS101 to iron stress. Increased abundances of proteins known to be involved in acclimation to iron stress and proteins known or predicted to be involved in iron uptake were observed, alongside decreases in the abundances of iron-binding proteins involved in photosynthesis and nitrogen fixation. Preferential loss of proteins with a high iron content contributed to overall reductions of 55-60% in estimated proteomic iron requirements. Changes in the abundances of iron-binding proteins also suggested the potential importance of alternate photosynthetic pathways as Trichodesmium reallocates the limiting resource under iron stress. Trichodesmium therefore displays a significant and integrated proteomic response to iron availability that likely contributes to the ecological success of this species in the ocean.
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Affiliation(s)
- Joseph T. Snow
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, United Kingdom
- Stem Cell and Leukaemia Proteomics Laboratory, Manchester Academic Health Science Centre, The University of Manchester, Wolfson Molecular Imaging Centre, Manchester, United Kingdom
- * E-mail:
| | - Despo Polyviou
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, United Kingdom
| | - Paul Skipp
- Centre for Proteomic Research, University of Southampton, Southampton, United Kingdom
| | - Nathan A. M. Chrismas
- School of Geographical Sciences, University of Bristol, University Road, Clifton, Bristol, United Kingdom
| | - Andrew Hitchcock
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, United Kingdom
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, United Kingdom
| | - Richard Geider
- School of Biological Sciences, University of Essex, Colchester, United Kingdom
| | - C. Mark Moore
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, United Kingdom
| | - Thomas S. Bibby
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, United Kingdom
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21
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Sure S, Torriero AAJ, Gaur A, Li LH, Chen Y, Tripathi C, Adholeya A, Ackland ML, Kochar M. Inquisition of Microcystis aeruginosa and Synechocystis nanowires: characterization and modelling. Antonie van Leeuwenhoek 2015; 108:1213-25. [PMID: 26319534 DOI: 10.1007/s10482-015-0576-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 08/24/2015] [Indexed: 10/23/2022]
Abstract
Identification of extracellular conductive pilus-like structures (PLS) i.e. microbial nanowires has spurred great interest among scientists due to their potential applications in the fields of biogeochemistry, bioelectronics, bioremediation etc. Using conductive atomic force microscopy, we identified microbial nanowires in Microcystis aeruginosa PCC 7806 which is an aerobic, photosynthetic microorganism. We also confirmed the earlier finding that Synechocystis sp. PCC 6803 produces microbial nanowires. In contrast to the use of highly instrumented continuous flow reactors for Synechocystis reported earlier, we identified simple and optimum culture conditions which allow increased production of nanowires in both test cyanobacteria. Production of these nanowires in Synechocystis and Microcystis were found to be sensitive to the availability of carbon source and light intensity. These structures seem to be proteinaceous in nature and their diameter was found to be 4.5-7 and 8.5-11 nm in Synechocystis and M. aeruginosa, respectively. Characterization of Synechocystis nanowires by transmission electron microscopy and biochemical techniques confirmed that they are type IV pili (TFP) while nanowires in M. aeruginosa were found to be similar to an unnamed protein (GenBank : CAO90693.1). Modelling studies of the Synechocystis TFP subunit i.e. PilA1 indicated that strategically placed aromatic amino acids may be involved in electron transfer through these nanowires. This study identifies PLS from Microcystis which can act as nanowires and supports the earlier hypothesis that microbial nanowires are widespread in nature and play diverse roles.
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Affiliation(s)
- Sandeep Sure
- TERI-Deakin Nanobiotechnology Centre, TERI Gram, The Energy and Resources Institute, Gual Pahari, Gurgaon Faridabad Road, Gurgaon, 122 001, Haryana, India
| | - Angel A J Torriero
- Centre for Cellular and Molecular Biology, Deakin University, 221 Burwood Highway, Burwood, Melbourne, VIC, 3125, Australia
| | - Aditya Gaur
- TERI-Deakin Nanobiotechnology Centre, TERI Gram, The Energy and Resources Institute, Gual Pahari, Gurgaon Faridabad Road, Gurgaon, 122 001, Haryana, India
| | - Lu Hua Li
- Institute for Frontier Materials, Deakin University, Geelong Waurn Ponds Campus, Geelong, VIC, 3216, Australia
| | - Ying Chen
- Institute for Frontier Materials, Deakin University, Geelong Waurn Ponds Campus, Geelong, VIC, 3216, Australia
| | - Chandrakant Tripathi
- TERI-Deakin Nanobiotechnology Centre, TERI Gram, The Energy and Resources Institute, Gual Pahari, Gurgaon Faridabad Road, Gurgaon, 122 001, Haryana, India
| | - Alok Adholeya
- TERI-Deakin Nanobiotechnology Centre, TERI Gram, The Energy and Resources Institute, Gual Pahari, Gurgaon Faridabad Road, Gurgaon, 122 001, Haryana, India
| | - M Leigh Ackland
- Centre for Cellular and Molecular Biology, Deakin University, 221 Burwood Highway, Burwood, Melbourne, VIC, 3125, Australia
| | - Mandira Kochar
- TERI-Deakin Nanobiotechnology Centre, TERI Gram, The Energy and Resources Institute, Gual Pahari, Gurgaon Faridabad Road, Gurgaon, 122 001, Haryana, India.
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22
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Schuergers N, Wilde A. Appendages of the cyanobacterial cell. Life (Basel) 2015; 5:700-15. [PMID: 25749611 PMCID: PMC4390875 DOI: 10.3390/life5010700] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Revised: 02/12/2015] [Accepted: 02/25/2015] [Indexed: 12/29/2022] Open
Abstract
Extracellular non-flagellar appendages, called pili or fimbriae, are widespread in gram-negative bacteria. They are involved in many different functions, including motility, adhesion, biofilm formation, and uptake of DNA. Sequencing data for a large number of cyanobacterial genomes revealed that most of them contain genes for pili synthesis. However, only for a very few cyanobacteria structure and function of these appendages have been analyzed. Here, we review the structure and function of type IV pili in Synechocystis sp. PCC 6803 and analyze the distribution of type IV pili associated genes in other cyanobacteria. Further, we discuss the role of the RNA-chaperone Hfq in pilus function and the presence of genes for the chaperone-usher pathway of pilus assembly in cyanobacteria.
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Affiliation(s)
- Nils Schuergers
- University of Freiburg, Institute of Biology III, Schänzlestr. 1, 79104 Freiburg, Germany.
| | - Annegret Wilde
- University of Freiburg, Institute of Biology III, Schänzlestr. 1, 79104 Freiburg, Germany.
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