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Broussos PI, Romanos GE, Stamatakis K. Salt and heat stress enhances hydrogen production in cyanobacteria. PHOTOSYNTHESIS RESEARCH 2024; 161:117-125. [PMID: 38546812 DOI: 10.1007/s11120-024-01098-2] [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: 11/24/2023] [Accepted: 03/22/2024] [Indexed: 07/25/2024]
Abstract
Cyanobacteria are among the most suitable organisms for the capture of excessive amounts of CO2 and can be grown in extreme environments. In our research we use the single-celled freshwater cyanobacteria Synechococcus elongatus PCC7942 PAMCOD strain and Synechocystis sp. PCC6714 for the production of carbohydrates and hydrogen. PAMCOD strain and Synechocystis sp. PCC6714 synthesize sucrose when exposed to salinity stress, as their main compatible osmolyte. We examined the cell proliferation rate and the sucrose accumulation in those two different strains of cyanobacteria under salt (0.4 M NaCl) and heat stress (35 0C) conditions. The intracellular sucrose (mol sucrose content per Chl a) was found to increase by 50% and 108% in PAMCOD strain and Synechocystis sp. PCC6714 cells, respectively. As previously reported, PAMCOD strain has the ability to produce hydrogen through the process of dark anaerobic fermentation (Vayenos D, Romanos GE, Papageorgiou GC, Stamatakis K (2020) Photosynth Res 146, 235-245). In the present study, we demonstrate that Synechocystis sp. PCC6714 has also this ability. We further examined the optimal conditions during the dark fermentation of PAMCOD and Synechocystis sp. PCC6714 regarding H2 formation, increasing the PAMCOD H2 productivity from 2 nmol H2 h- 1 mol Chl a- 1 to 23 nmol H2 h- 1 mol Chl a- 1. Moreover, after the dark fermentation, the cells demonstrated proliferation in both double BG-11 and BG-11 medium enriched in NaNO3, thus showing the sustainability of the procedure.
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Affiliation(s)
- Panayiotis-Ilias Broussos
- Institute of Biosciences and Applications, NCSR Demokritos, Patr. Gregoriou E & Neapoleos 27, 15341 Agia Paraskevi, Attikis, Greece
| | - George E Romanos
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, Patr. Gregoriou E & Neapoleos 27, 15341 Agia Paraskevi, Attikis, Greece
| | - Kostas Stamatakis
- Institute of Biosciences and Applications, NCSR Demokritos, Patr. Gregoriou E & Neapoleos 27, 15341 Agia Paraskevi, Attikis, Greece.
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2
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Watanabe S, Stazic D, Georg J, Ohtake S, Sakamaki Y, Numakura M, Asayama M, Chibazakura T, Wilde A, Steglich C, Hess WR. Regulation of RNase E during the UV stress response in the cyanobacterium Synechocystis sp. PCC 6803. MLIFE 2023; 2:43-57. [PMID: 38818332 PMCID: PMC10989929 DOI: 10.1002/mlf2.12056] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 12/07/2022] [Accepted: 12/15/2022] [Indexed: 06/01/2024]
Abstract
Endoribonucleases govern the maturation and degradation of RNA and are indispensable in the posttranscriptional regulation of gene expression. A key endoribonuclease in Gram-negative bacteria is RNase E. To ensure an appropriate supply of RNase E, some bacteria, such as Escherichia coli, feedback-regulate RNase E expression via the rne 5'-untranslated region (5' UTR) in cis. However, the mechanisms involved in the control of RNase E in other bacteria largely remain unknown. Cyanobacteria rely on solar light as an energy source for photosynthesis, despite the inherent ultraviolet (UV) irradiation. In this study, we first investigated globally the changes in gene expression in the cyanobacterium Synechocystis sp. PCC 6803 after a brief exposure to UV. Among the 407 responding genes 2 h after UV exposure was a prominent upregulation of rne mRNA level. Moreover, the enzymatic activity of RNase E rapidly increased as well, although the protein stability decreased. This unique response was underpinned by the increased accumulation of full-length rne mRNA caused by the stabilization of its 5' UTR and suppression of premature transcriptional termination, but not by an increased transcription rate. Mapping of RNA 3' ends and in vitro cleavage assays revealed that RNase E cleaves within a stretch of six consecutive uridine residues within the rne 5' UTR, indicating autoregulation. These observations suggest that RNase E in cyanobacteria contributes to reshaping the transcriptome during the UV stress response and that its required activity level is secured at the RNA level despite the enhanced turnover of the protein.
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Affiliation(s)
- Satoru Watanabe
- Faculty of Biology, Genetics and Experimental BioinformaticsUniversity of FreiburgFreiburgGermany
| | - Damir Stazic
- Department of BioscienceTokyo University of AgricultureSetagaya‐kuTokyoJapan
- Present address:
NexxiotPrime Tower (Hardstrasse 201)ZurichSwitzerland
| | - Jens Georg
- Department of BioscienceTokyo University of AgricultureSetagaya‐kuTokyoJapan
| | - Shota Ohtake
- Faculty of Biology, Genetics and Experimental BioinformaticsUniversity of FreiburgFreiburgGermany
| | - Yutaka Sakamaki
- Faculty of Biology, Genetics and Experimental BioinformaticsUniversity of FreiburgFreiburgGermany
| | - Megumi Numakura
- Faculty of Biology, Genetics and Experimental BioinformaticsUniversity of FreiburgFreiburgGermany
| | - Munehiko Asayama
- School of Agriculture, Molecular GeneticsIbaraki UniversityIbarakiJapan
| | - Taku Chibazakura
- Faculty of Biology, Genetics and Experimental BioinformaticsUniversity of FreiburgFreiburgGermany
| | - Annegret Wilde
- Faculty of Biology, Molecular GeneticsUniversity of FreiburgFreiburgGermany
| | - Claudia Steglich
- Department of BioscienceTokyo University of AgricultureSetagaya‐kuTokyoJapan
| | - Wolfgang R. Hess
- Department of BioscienceTokyo University of AgricultureSetagaya‐kuTokyoJapan
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Kariyazono R, Osanai T. Identification of the genome-wide distribution of cyanobacterial group-2 sigma factor SigE, accountable for its regulon. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 110:548-561. [PMID: 35092706 DOI: 10.1111/tpj.15687] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/18/2022] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Affiliation(s)
- Ryo Kariyazono
- School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa, 214-8571, Japan
| | - Takashi Osanai
- School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa, 214-8571, Japan
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4
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Bozan M, Schmid A, Bühler K. Evaluation of self-sustaining cyanobacterial biofilms for technical applications. Biofilm 2022; 4:100073. [PMID: 35434604 PMCID: PMC9006728 DOI: 10.1016/j.bioflm.2022.100073] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/14/2022] [Accepted: 03/02/2022] [Indexed: 11/27/2022] Open
Abstract
Cyanobacteria are potent microorganisms for sustainable photo-biotechnological production processes, as they are depending mainly on water, light, and carbon dioxide. Persisting challenges preventing their application include low biomass, as well as insufficient process stability and productivity. Here, we evaluate different cyanobacteria to be applied in a novel capillary biofilm reactor. Cultivated as biofilms, the organisms self-immobilize to the reactor walls, reach high biomass and enable long and robust production processes. As ‘best performer’ Tolypothrix sp. PCC 7712 emerged from this study. It reached the highest biomass in the reactors with 62.6 ± 6.34 gBDWL−1, produced 0.14 μmole H2 mgChl a−1h−1 under N2-fixing conditions, showed optimal surface coverage of the available growth surface, and only minor detachment in contrast to other tested species, highlighting its potential for photobiotechnology in the near future. Testing biofilm forming ability of selected cyanobacterial strains in a technical setting. Tolypothrix sp. PCC 7712 shows the highest biomass, 62.6 ± 6.34 gBDWL−1, the lowest detachment, and high surface coverage. Continuous H2 production under N2 fixation conditions. Tolypothrix sp. PCC 7712 as new photo-biotechnology workhorse.
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Riediger M, Hernández-Prieto MA, Song K, Hess WR, Futschik ME. Genome-wide identification and characterization of Fur-binding sites in the cyanobacteria Synechocystis sp. PCC 6803 and PCC 6714. DNA Res 2021; 28:6407143. [PMID: 34672328 PMCID: PMC8634477 DOI: 10.1093/dnares/dsab023] [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: 06/21/2021] [Accepted: 10/16/2021] [Indexed: 11/16/2022] Open
Abstract
The Ferric uptake regulator (Fur) is crucial to both pathogenic and non-pathogenic bacteria for the maintenance of iron homeostasis as well as the defence against reactive oxygen species. Based on datasets from the genome-wide mapping of transcriptional start sites and transcriptome data, we identified a high confidence regulon controlled by Fur for the model cyanobacterium Synechocystis sp. PCC 6803 and its close relative, strain 6714, based on the conserved strong iron starvation response and Fur-binding site occurrence. This regulon comprises 33 protein-coding genes and the sRNA IsaR1 that are under the control of 16 or 14 individual promoters in strains 6803 and 6714, respectively. The associated gene functions are mostly restricted to transporters and enzymes involved in the uptake and storage of iron ions, with few exceptions or unknown functional relevance. Within the isiABC operon, we identified a previously neglected gene encoding a small cysteine-rich protein, which we suggest calling, IsiE. The regulation of iron uptake, storage, and utilization ultimately results from the interplay between the Fur regulon, several other transcription factors, the FtsH3 protease, and the sRNA IsaR1.
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Affiliation(s)
- Matthias Riediger
- Institute of Biology III, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Miguel A Hernández-Prieto
- ARC Centre of Excellence for Translational Photosynthesis & School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Kuo Song
- Institute of Biology III, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Wolfgang R Hess
- Institute of Biology III, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Matthias E Futschik
- SysBioLab, Centre of Marine Sciences (CCMAR), University of Algarve, 8005-139 Faro, Portugal.,MRC London Institute of Medical Sciences (LMS), Faculty of Medicine, Imperial College London, London W12 0NN, UK
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Maeda K, Okuda Y, Enomoto G, Watanabe S, Ikeuchi M. Biosynthesis of a sulfated exopolysaccharide, synechan, and bloom formation in the model cyanobacterium Synechocystis sp. strain PCC 6803. eLife 2021; 10:66538. [PMID: 34127188 PMCID: PMC8205485 DOI: 10.7554/elife.66538] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 05/07/2021] [Indexed: 01/10/2023] Open
Abstract
Extracellularpolysaccharides of bacteria contribute to biofilm formation, stress tolerance, and infectivity. Cyanobacteria, the oxygenic photoautotrophic bacteria, uniquely produce sulfated extracellular polysaccharides among bacteria to support phototrophic biofilms. In addition, sulfated polysaccharides of cyanobacteria and other organisms have been focused as beneficial biomaterial. However, very little is known about their biosynthesis machinery and function in cyanobacteria. Here, we found that the model cyanobacterium, Synechocystis sp. strain PCC 6803, formed bloom-like cell aggregates embedded in sulfated extracellular polysaccharides (designated as synechan) and identified whole set of genes responsible for synechan biosynthesis and its transcriptional regulation, thereby suggesting a model for the synechan biosynthesis apparatus. Because similar genes are found in many cyanobacterial genomes with wide variation, our findings may lead elucidation of various sulfated polysaccharides, their functions, and their potential application in biotechnology. Bacteria are single-cell microorganisms that can form communities called biofilms, which stick to surfaces such as rocks, plants or animals. Biofilms confer protection to bacteria and allow them to colonize new environments. The physical scaffold of biofilms is a viscous matrix made of several molecules, the main one being polysaccharides, complex carbohydrates formed by many monosaccharides (single sugar molecules) joined together. Cyanobacteria, also known as blue-green algae, are a type of bacteria that produce oxygen and use sunlight as an energy source, just as plants and algae do. Cyanobacteria produce extracellular polysaccharides that contain sulfate groups. These sulfated polysaccharides are also produced by animals and algae but are not common in other bacteria or plants. One possible role of sulfated, extracellular polysaccharides in cyanobacteria is keeping cells together in the floating aggregates found in cyanobacterial blooms. These are visible discolorations of the water caused by an overgrowth of cyanobacteria that occur in lakes, estuaries and coastal waters. However, little is known about how these polysaccharides are synthesized in cyanobacteria and what their natural role is. Maeda et al. found a strain of cyanobacteria that formed bloom-like aggregates that were embedded in sulfated extracellular polysaccharides. Using genetic engineering techniques, the researchers identified a set of genes responsible for producing a sulfated extracellular polysaccharide and regulating its levels. They also found that cell aggregates of cyanobacteria can float without having intracellular gas vesicles, which was previously thought to enable blooms to float. The results of the present study could have applications for human health, since many sulfated polysaccharides have antiviral, antitumor or anti-inflammatory properties, and similar genes are found in many cyanobacteria. In addition, these findings could be useful for controlling toxic cyanobacterial blooms, which are becoming increasingly problematic for society.
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Affiliation(s)
- Kaisei Maeda
- Department of Life Sciences (Biology), Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan
| | - Yukiko Okuda
- Department of Life Sciences (Biology), Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan
| | - Gen Enomoto
- Department of Life Sciences (Biology), Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan
| | - Satoru Watanabe
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Masahiko Ikeuchi
- Department of Life Sciences (Biology), Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan.,Faculty of Education and Integrated Arts and Sciences, Waseda University, Tokyo, Japan
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Zhan J, Steglich C, Scholz I, Hess WR, Kirilovsky D. Inverse regulation of light harvesting and photoprotection is mediated by a 3'-end-derived sRNA in cyanobacteria. THE PLANT CELL 2021; 33:358-380. [PMID: 33793852 PMCID: PMC8136909 DOI: 10.1093/plcell/koaa030] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 12/01/2020] [Indexed: 06/12/2023]
Abstract
Phycobilisomes (PBSs), the principal cyanobacterial antenna, are among the most efficient macromolecular structures in nature, and are used for both light harvesting and directed energy transfer to the photosynthetic reaction center. However, under unfavorable conditions, excess excitation energy needs to be rapidly dissipated to avoid photodamage. The orange carotenoid protein (OCP) senses light intensity and induces thermal energy dissipation under stress conditions. Hence, its expression must be tightly controlled; however, the molecular mechanism of this regulation remains to be elucidated. Here, we describe the discovery of a posttranscriptional regulatory mechanism in Synechocystis sp. PCC 6803 in which the expression of the operon encoding the allophycocyanin subunits of the PBS is directly and in an inverse fashion linked to the expression of OCP. This regulation is mediated by ApcZ, a small regulatory RNA that is derived from the 3'-end of the tetracistronic apcABC-apcZ operon. ApcZ inhibits ocp translation under stress-free conditions. Under most stress conditions, apc operon transcription decreases and ocp translation increases. Thus, a key operon involved in the collection of light energy is functionally connected to the expression of a protein involved in energy dissipation. Our findings support the view that regulatory RNA networks in bacteria evolve through the functionalization of mRNA 3'-UTRs.
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Affiliation(s)
- Jiao Zhan
- Université Paris-Saclay, Commissariat à l’Énergie Atomiques et aux Énergies Alternatives, Centre National de la Recherche Scientifique (CEA, CNRS), Institute for Integrative Biology of the Cell (I2BC), 91198 Gif sur Yvette, France
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Claudia Steglich
- Faculty of Biology, Institute of Biology III, University of Freiburg, D-79104 Freiburg im Breisgau, Germany
| | - Ingeborg Scholz
- Faculty of Biology, Institute of Biology III, University of Freiburg, D-79104 Freiburg im Breisgau, Germany
| | - Wolfgang R Hess
- Faculty of Biology, Institute of Biology III, University of Freiburg, D-79104 Freiburg im Breisgau, Germany
| | - Diana Kirilovsky
- Université Paris-Saclay, Commissariat à l’Énergie Atomiques et aux Énergies Alternatives, Centre National de la Recherche Scientifique (CEA, CNRS), Institute for Integrative Biology of the Cell (I2BC), 91198 Gif sur Yvette, France
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8
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Genetic, Genomics, and Responses to Stresses in Cyanobacteria: Biotechnological Implications. Genes (Basel) 2021; 12:genes12040500. [PMID: 33805386 PMCID: PMC8066212 DOI: 10.3390/genes12040500] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/25/2021] [Accepted: 03/25/2021] [Indexed: 02/07/2023] Open
Abstract
Cyanobacteria are widely-diverse, environmentally crucial photosynthetic prokaryotes of great interests for basic and applied science. Work to date has focused mostly on the three non-nitrogen fixing unicellular species Synechocystis PCC 6803, Synechococcus PCC 7942, and Synechococcus PCC 7002, which have been selected for their genetic and physiological interests summarized in this review. Extensive "omics" data sets have been generated, and genome-scale models (GSM) have been developed for the rational engineering of these cyanobacteria for biotechnological purposes. We presently discuss what should be done to improve our understanding of the genotype-phenotype relationships of these models and generate robust and predictive models of their metabolism. Furthermore, we also emphasize that because Synechocystis PCC 6803, Synechococcus PCC 7942, and Synechococcus PCC 7002 represent only a limited part of the wide biodiversity of cyanobacteria, other species distantly related to these three models, should be studied. Finally, we highlight the need to strengthen the communication between academic researchers, who know well cyanobacteria and can engineer them for biotechnological purposes, but have a limited access to large photobioreactors, and industrial partners who attempt to use natural or engineered cyanobacteria to produce interesting chemicals at reasonable costs, but may lack knowledge on cyanobacterial physiology and metabolism.
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Mittermair S, Richter J, Doppler P, Trenzinger K, Nicoletti C, Forsich C, Spadiut O, Herwig C, Lackner M. Impact ofexoDgene knockout on the polyhydroxybutyrate overaccumulating mutant Mt_a24. INTERNATIONAL JOURNAL OF BIOBASED PLASTICS 2021. [DOI: 10.1080/24759651.2020.1863020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Sandra Mittermair
- Department of Chemistry and Biology, University of Applied Sciences Upper Austria, AG Biosciences , Wels, Austria
| | - Juliane Richter
- Department of Chemistry and Biology, University of Applied Sciences Upper Austria, AG Biosciences , Wels, Austria
| | - Philipp Doppler
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area Biochemical Engineering, Technische Universität Wien , Vienna, Austria
| | - Kevin Trenzinger
- Department of Chemistry and Biology, University of Applied Sciences Upper Austria, AG Biosciences , Wels, Austria
| | - Cecilia Nicoletti
- Department of Chemistry and Biology, University of Applied Sciences Upper Austria, AG Biosciences , Wels, Austria
| | - Christian Forsich
- Department of Materials Technology, University of Applied Sciences Upper Austria , Wels, Austria
| | - Oliver Spadiut
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area Biochemical Engineering, Technische Universität Wien , Vienna, Austria
| | - Christoph Herwig
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area Biochemical Engineering, Technische Universität Wien , Vienna, Austria
| | - Maximilian Lackner
- Lackner Ventures & Consulting GmbH , Vienna, Austria
- University of Applied Sciences Technikum Wien , Vienna, Austria
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Abstract
While the model bacteria Escherichia coli and Bacillus subtilis harbor single chromosomes, which is known as monoploidy, some freshwater cyanobacteria contain multiple chromosome copies per cell throughout their cell cycle, which is known as polyploidy. In the model cyanobacteria Synechococcus elongatus PCC 7942 and Synechocystis sp. PCC 6803, chromosome copy number (ploidy) is regulated in response to growth phase and environmental factors. In S. elongatus 7942, chromosome replication is asynchronous both among cells and chromosomes. Comparative analysis of S. elongatus 7942 and S. sp. 6803 revealed a variety of DNA replication mechanisms. In this review, the current knowledge of ploidy and DNA replication mechanisms in cyanobacteria is summarized together with information on the features common with plant chloroplasts. It is worth noting that the occurrence of polyploidy and its regulation are correlated with certain cyanobacterial lifestyles and are shared between some cyanobacteria and chloroplasts. ABBREVIATIONS NGS: next-generation sequencing; Repli-seq: replication sequencing; BrdU: 5-bromo-2'-deoxyuridine; TK: thymidine kinase; GCSI: GC skew index; PET: photosynthetic electron transport; RET: respiration electron transport; Cyt b6f complex: cytochrome b6f complex; PQ: plastoquinone; PC: plastocyanin.
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Affiliation(s)
- Satoru Watanabe
- Department of Bioscience, Tokyo University of Agriculture , Tokyo, Japan
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Kunjapur AM, Prather KLJ. Development of a Vanillate Biosensor for the Vanillin Biosynthesis Pathway in E. coli. ACS Synth Biol 2019; 8:1958-1967. [PMID: 31461264 DOI: 10.1021/acssynbio.9b00071] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The engineered de novo vanillin biosynthesis pathway constructed in Escherichia coli is industrially relevant but limited by the reaction catalyzed by catechol O-methyltransferase, which is intended to catalyze the conversion of protocatechuate to vanillate. To identify alternative O-methyltransferases, we constructed a vanillate sensor based on the Caulobacter crescentus VanR-VanO system. Using an E. coli promoter library, we achieved greater than 14-fold dynamic range in our best rationally constructed sensor. We found that this construct and an evolved variant demonstrate remarkable substrate selectivity, exhibiting no detectable response to the regioisomer byproduct isovanillate and minimal response to structurally similar pathway intermediates. We then harnessed the evolved biosensor to conduct rapid bioprospecting of natural catechol O-methyltransferases and identified three previously uncharacterized but active O-methyltransferases. Collectively, these efforts enrich our knowledge of how biosensing can aid metabolic engineering and constitute the foundation for future improvements in vanillin pathway productivity.
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Affiliation(s)
- Aditya M. Kunjapur
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Kristala L. J. Prather
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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12
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Abstract
Global (metabolic) regulatory networks allow microorganisms to survive periods of nitrogen starvation or general nutrient stress. Uptake and utilization of various nitrogen sources are thus commonly tightly regulated in Prokarya (Bacteria and Archaea) in response to available nitrogen sources. Those well-studied regulations occur mainly at the transcriptional and posttranslational level. Surprisingly, and in contrast to their involvement in most other stress responses, small RNAs (sRNAs) involved in the response to environmental nitrogen fluctuations are only rarely reported. In addition to sRNAs indirectly affecting nitrogen metabolism, only recently it was demonstrated that three sRNAs were directly involved in regulation of nitrogen metabolism in response to changes in available nitrogen sources. All three trans-acting sRNAs are under direct transcriptional control of global nitrogen regulators and affect expression of components of nitrogen metabolism (glutamine synthetase, nitrogenase, and PII-like proteins) by either masking the ribosome binding site and thus inhibiting translation initiation or stabilizing the respective target mRNAs. Most likely, there are many more sRNAs and other types of noncoding RNAs, e.g., riboswitches, involved in the regulation of nitrogen metabolism in Prokarya that remain to be uncovered. The present review summarizes the current knowledge on sRNAs involved in nitrogen metabolism and their biological functions and targets.
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Alex A, Antunes A. Genus-wide comparison of Pseudovibrio bacterial genomes reveal diverse adaptations to different marine invertebrate hosts. PLoS One 2018; 13:e0194368. [PMID: 29775460 PMCID: PMC5959193 DOI: 10.1371/journal.pone.0194368] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 03/01/2018] [Indexed: 11/18/2022] Open
Abstract
Bacteria belonging to the genus Pseudovibrio have been frequently found in association with a wide variety of marine eukaryotic invertebrate hosts, indicative of their versatile and symbiotic lifestyle. A recent comparison of the sponge-associated Pseudovibrio genomes has shed light on the mechanisms influencing a successful symbiotic association with sponges. In contrast, the genomic architecture of Pseudovibrio bacteria associated with other marine hosts has received less attention. Here, we performed genus-wide comparative analyses of 18 Pseudovibrio isolated from sponges, coral, tunicates, flatworm, and seawater. The analyses revealed a certain degree of commonality among the majority of sponge- and coral-associated bacteria. Isolates from other marine invertebrate host, tunicates, exhibited a genetic repertoire for cold adaptation and specific metabolic abilities including mucin degradation in the Antarctic tunicate-associated bacterium Pseudovibrio sp. Tun.PHSC04_5.I4. Reductive genome evolution was simultaneously detected in the flatworm-associated bacteria and the sponge-associated bacterium P. axinellae AD2, through the loss of major secretion systems (type III/VI) and virulence/symbioses factors such as proteins involved in adhesion and attachment to the host. Our study also unraveled the presence of a CRISPR-Cas system in P. stylochi UST20140214-052 a flatworm-associated bacterium possibly suggesting the role of CRISPR-based adaptive immune system against the invading virus particles. Detection of mobile elements and genomic islands (GIs) in all bacterial members highlighted the role of horizontal gene transfer for the acquisition of novel genetic features, likely enhancing the bacterial ecological fitness. These findings are insightful to understand the role of genome diversity in Pseudovibrio as an evolutionary strategy to increase their colonizing success across a wide range of marine eukaryotic hosts.
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Affiliation(s)
- Anoop Alex
- CIIMAR/CIMAR, Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Porto, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal
- * E-mail: (AA); (AA)
| | - Agostinho Antunes
- CIIMAR/CIMAR, Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Porto, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal
- * E-mail: (AA); (AA)
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The host-encoded RNase E endonuclease as the crRNA maturation enzyme in a CRISPR-Cas subtype III-Bv system. Nat Microbiol 2018; 3:367-377. [PMID: 29403013 DOI: 10.1038/s41564-017-0103-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 12/20/2017] [Indexed: 02/08/2023]
Abstract
Specialized RNA endonucleases for the maturation of clustered regularly interspaced short palindromic repeat (CRISPR)-derived RNAs (crRNAs) are critical in CRISPR-CRISPR-associated protein (Cas) defence mechanisms. The Cas6 and Cas5d enzymes are the RNA endonucleases in many class 1 CRISPR-Cas systems. In some class 2 systems, maturation and effector functions are combined within a single enzyme or maturation proceeds through the combined actions of RNase III and trans-activating CRISPR RNAs (tracrRNAs). Three separate CRISPR-Cas systems exist in the cyanobacterium Synechocystis sp. PCC 6803. Whereas Cas6-type enzymes act in two of these systems, the third, which is classified as subtype III-B variant (III-Bv), lacks cas6 homologues. Instead, the maturation of crRNAs proceeds through the activity of endoribonuclease E, leaving unusual 13- and 14-nucleotide-long 5'-handles. Overexpression of RNase E leads to overaccumulation and knock-down to the reduced accumulation of crRNAs in vivo, suggesting that RNase E is the limiting factor for CRISPR complex formation. Recognition by RNase E depends on a stem-loop in the CRISPR repeat, whereas base substitutions at the cleavage site trigger the appearance of secondary products, consistent with a two-step recognition and cleavage mechanism. These results suggest the adaptation of an otherwise very conserved housekeeping enzyme to accommodate new substrates and illuminate the impressive plasticity of CRISPR-Cas systems that enables them to function in particular genomic environments.
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Rai S, Lucius S, Kern R, Bauwe H, Kaplan A, Kopka J, Hagemann M. The Synechocystis sp. PCC 6803 Genome Encodes Up to Four 2-Phosphoglycolate Phosphatases. FRONTIERS IN PLANT SCIENCE 2018; 9:1718. [PMID: 30542360 PMCID: PMC6278635 DOI: 10.3389/fpls.2018.01718] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 11/05/2018] [Indexed: 05/07/2023]
Abstract
Photorespiratory phosphoglycolate (2PG) metabolism is essential for cyanobacteria, algae, and plants. The first enzyme of the pathway, 2PG phosphatase (PGPase), is known from plants and algae but was scarcely investigated in cyanobacteria. In silico analysis revealed four candidate genes (slr0458, slr0586, sll1349, and slr1762) in the genome of the model cyanobacterium Synechocystis sp. PCC 6803 that all belong to the 2-haloacid dehalogenase (HAD) superfamily and could possibly encode PGPase proteins. However, in contrast to known algal and plant PGPases, the putative cyanobacterial PGPases belong to another HAD subfamily implying that PGPases in eukaryotic phototrophs did not originate from cyanobacterial PGPases. To verify their function, these four genes were inactivated both individually and in combination. A mild high-CO2-requiring (HCR) growth phenotype typical for photorespiratory mutants was observed only in Δsll1349. Combinatorial inactivation enhanced the HCR phenotype in specific double and triple mutants. Heterologous expression of the putative cyanobacterial PGPases in E. coli led to higher PGPase activities in crude cell extracts, but only the purified Slr0458 protein showed PGPase activity. Hence, we propose that a consortium of up to four photorespiratory PGPases may initiate photorespiratory 2PG metabolism in Synechocystis. We suggest that redundancy of this essential enzyme activity could be related to the highly adaptive lifestyle of cyanobacteria such as Synechocystis sp. PCC 6803, which allows them to grow under very diverse conditions.
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Affiliation(s)
- Snigdha Rai
- Department of Plant Physiology, University of Rostock, Rostock, Germany
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi, India
| | - Stefan Lucius
- Department of Plant Physiology, University of Rostock, Rostock, Germany
| | - Ramona Kern
- Department of Plant Physiology, University of Rostock, Rostock, Germany
| | - Hermann Bauwe
- Department of Plant Physiology, University of Rostock, Rostock, Germany
| | - Aaron Kaplan
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Joachim Kopka
- Applied Metabolome Analysis, Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Martin Hagemann
- Department of Plant Physiology, University of Rostock, Rostock, Germany
- Department Life, Light and Matter, University of Rostock, Rostock, Germany
- *Correspondence: Martin Hagemann,
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16
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Teng JLL, Yeung ML, Chan E, Jia L, Lin CH, Huang Y, Tse H, Wong SSY, Sham PC, Lau SKP, Woo PCY. PacBio But Not Illumina Technology Can Achieve Fast, Accurate and Complete Closure of the High GC, Complex Burkholderia pseudomallei Two-Chromosome Genome. Front Microbiol 2017; 8:1448. [PMID: 28824579 PMCID: PMC5539568 DOI: 10.3389/fmicb.2017.01448] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 07/17/2017] [Indexed: 12/19/2022] Open
Abstract
Although PacBio third-generation sequencers have improved the read lengths of genome sequencing which facilitates the assembly of complete genomes, no study has reported success in using PacBio data alone to completely sequence a two-chromosome bacterial genome from a single library in a single run. Previous studies using earlier versions of sequencing chemistries have at most been able to finish bacterial genomes containing only one chromosome with de novo assembly. In this study, we compared the robustness of PacBio RS II, using one SMRT cell and the latest P6-C4 chemistry, with Illumina HiSeq 1500 in sequencing the genome of Burkholderia pseudomallei, a bacterium which contains two large circular chromosomes, very high G+C content of 68–69%, highly repetitive regions and substantial genomic diversity, and represents one of the largest and most complex bacterial genomes sequenced, using a reference genome generated by hybrid assembly using PacBio and Illumina datasets with subsequent manual validation. Results showed that PacBio data with de novo assembly, but not Illumina, was able to completely sequence the B. pseudomallei genome without any gaps or mis-assemblies. The two large contigs of the PacBio assembly aligned unambiguously to the reference genome, sharing >99.9% nucleotide identities. Conversely, Illumina data assembled using three different assemblers resulted in fragmented assemblies (201–366 contigs), sharing only 92.2–100% and 92.0–100% nucleotide identities to chromosomes I and II reference sequences, respectively, with no indication that the B. pseudomallei genome consisted of two chromosomes with four copies of ribosomal operons. Among all assemblies, the PacBio assembly recovered the highest number of core and virulence proteins, and housekeeping genes based on whole-genome multilocus sequence typing (wgMLST). Most notably, assembly solely based on PacBio outperformed even hybrid assembly using both PacBio and Illumina datasets. Hybrid approach generated only 74 contigs, while the PacBio data alone with de novo assembly achieved complete closure of the two-chromosome B. pseudomallei genome without additional costly bench work and further sequencing. PacBio RS II using P6-C4 chemistry is highly robust and cost-effective and should be the platform of choice in sequencing bacterial genomes, particularly for those that are well-known to be difficult-to-sequence.
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Affiliation(s)
- Jade L L Teng
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong KongHong Kong, Hong Kong.,State Key Laboratory of Emerging Infectious Diseases, Department of MicrobiologyThe University of Hong Kong, Hong Kong, Hong Kong.,Research Centre of Infection and ImmunologyThe University of Hong Kong, Hong Kong, Hong Kong.,Carol Yu Centre for Infection, The University of Hong KongHong Kong, Hong Kong
| | - Man Lung Yeung
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong KongHong Kong, Hong Kong.,State Key Laboratory of Emerging Infectious Diseases, Department of MicrobiologyThe University of Hong Kong, Hong Kong, Hong Kong.,Research Centre of Infection and ImmunologyThe University of Hong Kong, Hong Kong, Hong Kong.,Carol Yu Centre for Infection, The University of Hong KongHong Kong, Hong Kong
| | - Elaine Chan
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong KongHong Kong, Hong Kong
| | - Lilong Jia
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong KongHong Kong, Hong Kong
| | - Chi Ho Lin
- Centre for Genomic Sciences, The University of Hong KongHong Kong, Hong Kong
| | - Yi Huang
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong KongHong Kong, Hong Kong
| | - Herman Tse
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong KongHong Kong, Hong Kong.,State Key Laboratory of Emerging Infectious Diseases, Department of MicrobiologyThe University of Hong Kong, Hong Kong, Hong Kong.,Research Centre of Infection and ImmunologyThe University of Hong Kong, Hong Kong, Hong Kong.,Carol Yu Centre for Infection, The University of Hong KongHong Kong, Hong Kong
| | - Samson S Y Wong
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong KongHong Kong, Hong Kong.,State Key Laboratory of Emerging Infectious Diseases, Department of MicrobiologyThe University of Hong Kong, Hong Kong, Hong Kong.,Research Centre of Infection and ImmunologyThe University of Hong Kong, Hong Kong, Hong Kong.,Carol Yu Centre for Infection, The University of Hong KongHong Kong, Hong Kong
| | - Pak Chung Sham
- Centre for Genomic Sciences, The University of Hong KongHong Kong, Hong Kong.,Department of Psychiatry, The University of Hong KongHong Kong, Hong Kong
| | - Susanna K P Lau
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong KongHong Kong, Hong Kong.,State Key Laboratory of Emerging Infectious Diseases, Department of MicrobiologyThe University of Hong Kong, Hong Kong, Hong Kong.,Research Centre of Infection and ImmunologyThe University of Hong Kong, Hong Kong, Hong Kong.,Carol Yu Centre for Infection, The University of Hong KongHong Kong, Hong Kong.,Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong KongHong Kong, Hong Kong
| | - Patrick C Y Woo
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong KongHong Kong, Hong Kong.,State Key Laboratory of Emerging Infectious Diseases, Department of MicrobiologyThe University of Hong Kong, Hong Kong, Hong Kong.,Research Centre of Infection and ImmunologyThe University of Hong Kong, Hong Kong, Hong Kong.,Carol Yu Centre for Infection, The University of Hong KongHong Kong, Hong Kong.,Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong KongHong Kong, Hong Kong
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17
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Pancrace C, Barny MA, Ueoka R, Calteau A, Scalvenzi T, Pédron J, Barbe V, Piel J, Humbert JF, Gugger M. Insights into the Planktothrix genus: Genomic and metabolic comparison of benthic and planktic strains. Sci Rep 2017; 7:41181. [PMID: 28117406 PMCID: PMC5259702 DOI: 10.1038/srep41181] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 12/16/2016] [Indexed: 01/12/2023] Open
Abstract
Planktothrix is a dominant cyanobacterial genus forming toxic blooms in temperate freshwater ecosystems. We sequenced the genome of planktic and non planktic Planktothrix strains to better represent this genus diversity and life style at the genomic level. Benthic and biphasic strains are rooting the Planktothrix phylogenetic tree and widely expand the pangenome of this genus. We further investigated in silico the genetic potential dedicated to gas vesicles production, nitrogen fixation as well as natural product synthesis and conducted complementary experimental tests by cell culture, microscopy and mass spectrometry. Significant differences for the investigated features could be evidenced between strains of different life styles. The benthic Planktothrix strains showed unexpected characteristics such as buoyancy, nitrogen fixation capacity and unique natural product features. In comparison with Microcystis, another dominant toxic bloom-forming genus in freshwater ecosystem, different evolutionary strategies were highlighted notably as Planktothrix exhibits an overall greater genetic diversity but a smaller genomic plasticity than Microcystis. Our results are shedding light on Planktothrix evolution, phylogeny and physiology in the frame of their diverse life styles.
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Affiliation(s)
- Claire Pancrace
- Institut Pasteur, Collection des Cyanobactéries, 28 rue du Dr Roux, 75724 Paris Cedex 05, France.,UMR UPMC 113, CNRS 7618, IRD 242, INRA 1392, PARIS 7 113, UPEC, IEES Paris, 4 Place Jussieu, 75005, Paris, France.,Université Pierre et Marie Curie (UPMC), 4 Place Jussieu, 75005, Paris, France
| | - Marie-Anne Barny
- UMR UPMC 113, CNRS 7618, IRD 242, INRA 1392, PARIS 7 113, UPEC, IEES Paris, 4 Place Jussieu, 75005, Paris, France
| | - Reiko Ueoka
- Institute of Microbiology, Eigenössische Technische Hochschule (ETH) Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Alexandra Calteau
- Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Genoscope &CNRS, UMR 8030, Laboratoire d'Analyse Bioinformatique en Génomique et Métabolisme, 2, rue Gaston Crémieux, CP 5706, 91057 EVRY cedex, France
| | - Thibault Scalvenzi
- Institut Pasteur, Collection des Cyanobactéries, 28 rue du Dr Roux, 75724 Paris Cedex 05, France
| | - Jacques Pédron
- UMR UPMC 113, CNRS 7618, IRD 242, INRA 1392, PARIS 7 113, UPEC, IEES Paris, 4 Place Jussieu, 75005, Paris, France
| | - Valérie Barbe
- Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Genoscope, Laboratoire de Biologie Moléculaire pour l'étude des Génomes, 2, rue Gaston Crémieux, CP 5706, 91057 EVRY cedex, France
| | - Joern Piel
- Institute of Microbiology, Eigenössische Technische Hochschule (ETH) Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Jean-François Humbert
- UMR UPMC 113, CNRS 7618, IRD 242, INRA 1392, PARIS 7 113, UPEC, IEES Paris, 4 Place Jussieu, 75005, Paris, France
| | - Muriel Gugger
- Institut Pasteur, Collection des Cyanobactéries, 28 rue du Dr Roux, 75724 Paris Cedex 05, France
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18
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Baumgartner D, Kopf M, Klähn S, Steglich C, Hess WR. Small proteins in cyanobacteria provide a paradigm for the functional analysis of the bacterial micro-proteome. BMC Microbiol 2016; 16:285. [PMID: 27894276 PMCID: PMC5126843 DOI: 10.1186/s12866-016-0896-z] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 11/14/2016] [Indexed: 12/21/2022] Open
Abstract
Background Despite their versatile functions in multimeric protein complexes, in the modification of enzymatic activities, intercellular communication or regulatory processes, proteins shorter than 80 amino acids (μ-proteins) are a systematically underestimated class of gene products in bacteria. Photosynthetic cyanobacteria provide a paradigm for small protein functions due to extensive work on the photosynthetic apparatus that led to the functional characterization of 19 small proteins of less than 50 amino acids. In analogy, previously unstudied small ORFs with similar degrees of conservation might encode small proteins of high relevance also in other functional contexts. Results Here we used comparative transcriptomic information available for two model cyanobacteria, Synechocystis sp. PCC 6803 and Synechocystis sp. PCC 6714 for the prediction of small ORFs. We found 293 transcriptional units containing candidate small ORFs ≤80 codons in Synechocystis sp. PCC 6803, also including the known mRNAs encoding small proteins of the photosynthetic apparatus. From these transcriptional units, 146 are shared between the two strains, 42 are shared with the higher plant Arabidopsis thaliana and 25 with E. coli. To verify the existence of the respective μ-proteins in vivo, we selected five genes as examples to which a FLAG tag sequence was added and re-introduced them into Synechocystis sp. PCC 6803. These were the previously annotated gene ssr1169, two newly defined genes norf1 and norf4, as well as nsiR6(nitrogen stress-induced RNA 6) and hliR1(high light-inducible RNA 1) , which originally were considered non-coding. Upon activation of expression via the Cu2+.responsive petE promoter or from the native promoters, all five proteins were detected in Western blot experiments. Conclusions The distribution and conservation of these five genes as well as their regulation of expression and the physico-chemical properties of the encoded proteins underline the likely great bandwidth of small protein functions in bacteria and makes them attractive candidates for functional studies.
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Affiliation(s)
- Desiree Baumgartner
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany
| | - Matthias Kopf
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany.,Present Address: Molecular Health GmbH, Kurfürsten-Anlage 21, 69115, Heidelberg, Germany
| | - Stephan Klähn
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany
| | - Claudia Steglich
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany
| | - Wolfgang R Hess
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany.
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19
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Winter S, Jahn K, Wehner S, Kuchenbecker L, Marz M, Stoye J, Böcker S. Finding approximate gene clusters with Gecko 3. Nucleic Acids Res 2016; 44:9600-9610. [PMID: 27679480 PMCID: PMC5175365 DOI: 10.1093/nar/gkw843] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 09/06/2016] [Accepted: 09/12/2016] [Indexed: 12/15/2022] Open
Abstract
Gene-order-based comparison of multiple genomes provides signals for functional analysis of genes and the evolutionary process of genome organization. Gene clusters are regions of co-localized genes on genomes of different species. The rapid increase in sequenced genomes necessitates bioinformatics tools for finding gene clusters in hundreds of genomes. Existing tools are often restricted to few (in many cases, only two) genomes, and often make restrictive assumptions such as short perfect conservation, conserved gene order or monophyletic gene clusters. We present Gecko 3, an open-source software for finding gene clusters in hundreds of bacterial genomes, that comes with an easy-to-use graphical user interface. The underlying gene cluster model is intuitive, can cope with low degrees of conservation as well as misannotations and is complemented by a sound statistical evaluation. To evaluate the biological benefit of Gecko 3 and to exemplify our method, we search for gene clusters in a dataset of 678 bacterial genomes using Synechocystis sp. PCC 6803 as a reference. We confirm detected gene clusters reviewing the literature and comparing them to a database of operons; we detect two novel clusters, which were confirmed by publicly available experimental RNA-Seq data. The computational analysis is carried out on a laptop computer in <40 min.
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Affiliation(s)
- Sascha Winter
- Chair for Bioinformatics, Institute for Computer Science, Friedrich-Schiller-University Jena, Jena, Germany
| | - Katharina Jahn
- Genome Informatics, Faculty of Technology and Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
- Computational Biology Group, Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
- SIB Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Stefanie Wehner
- RNA Bioinformatics and High Throughput Analysis, Institute for Computer Science, Friedrich-Schiller-University Jena, Jena, Germany
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, FK9LA, Scotland, UK
| | - Leon Kuchenbecker
- Genome Informatics, Faculty of Technology and Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
- Berlin-Brandenburg Center for Regenerative Therapies, Charité University Medicine Berlin, Berlin, Germany
| | - Manja Marz
- RNA Bioinformatics and High Throughput Analysis, Institute for Computer Science, Friedrich-Schiller-University Jena, Jena, Germany
- Leibniz Institute for Age Research-Fritz Lipmann Institute (FLI), Jena, Germany
| | - Jens Stoye
- Genome Informatics, Faculty of Technology and Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Sebastian Böcker
- Chair for Bioinformatics, Institute for Computer Science, Friedrich-Schiller-University Jena, Jena, Germany
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20
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Type II Toxin-Antitoxin Systems in the Unicellular Cyanobacterium Synechocystis sp. PCC 6803. Toxins (Basel) 2016; 8:toxins8070228. [PMID: 27455323 PMCID: PMC4963859 DOI: 10.3390/toxins8070228] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 07/11/2016] [Indexed: 12/03/2022] Open
Abstract
Bacterial toxin–antitoxin (TA) systems are genetic elements, which are encoded by plasmid as well as chromosomal loci. They mediate plasmid and genomic island maintenance through post-segregational killing mechanisms but may also have milder effects, acting as mobile stress response systems that help certain cells of a population in persisting adverse growth conditions. Very few cyanobacterial TA system have been characterized thus far. In this work, we focus on the cyanobacterium Synechocystis 6803, a widely used model organism. We expand the number of putative Type II TA systems from 36 to 69 plus seven stand-alone components. Forty-seven TA pairs are located on the chromosome and 22 are plasmid-located. Different types of toxins are associated with various antitoxins in a mix and match principle. According to protein domains and experimental data, 81% of all toxins in Synechocystis 6803 likely exhibit RNase activity, suggesting extensive potential for toxicity-related RNA degradation and toxin-mediated transcriptome remodeling. Of particular interest is the Ssr8013–Slr8014 system encoded on plasmid pSYSG, which is part of a larger defense island or the pSYSX system Slr6056–Slr6057, which is linked to a bacterial ubiquitin-like system. Consequently, Synechocystis 6803 is one of the most prolific sources of new information about these genetic elements.
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21
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D'Arrigo I, Bojanovič K, Yang X, Holm Rau M, Long KS. Genome-wide mapping of transcription start sites yields novel insights into the primary transcriptome ofPseudomonas putida. Environ Microbiol 2016; 18:3466-3481. [DOI: 10.1111/1462-2920.13326] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/01/2016] [Indexed: 01/09/2023]
Affiliation(s)
- Isotta D'Arrigo
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark; Kogle Allé 6 DK-2970 Hørsholm Denmark
| | - Klara Bojanovič
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark; Kogle Allé 6 DK-2970 Hørsholm Denmark
| | - Xiaochen Yang
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark; Kogle Allé 6 DK-2970 Hørsholm Denmark
| | - Martin Holm Rau
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark; Kogle Allé 6 DK-2970 Hørsholm Denmark
| | - Katherine S. Long
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark; Kogle Allé 6 DK-2970 Hørsholm Denmark
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22
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Bravakos P, Kotoulas G, Skaraki K, Pantazidou A, Economou-Amilli A. A polyphasic taxonomic approach in isolated strains of Cyanobacteria from thermal springs of Greece. Mol Phylogenet Evol 2016; 98:147-60. [DOI: 10.1016/j.ympev.2016.02.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 02/08/2016] [Accepted: 02/12/2016] [Indexed: 01/11/2023]
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23
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Klanchui A, Raethong N, Prommeenate P, Vongsangnak W, Meechai A. Cyanobacterial Biofuels: Strategies and Developments on Network and Modeling. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 160:75-102. [PMID: 27783135 DOI: 10.1007/10_2016_42] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cyanobacteria, the phototrophic microorganisms, have attracted much attention recently as a promising source for environmentally sustainable biofuels production. However, barriers for commercial markets of cyanobacteria-based biofuels concern the economic feasibility. Miscellaneous strategies for improving the production performance of cyanobacteria have thus been developed. Among these, the simple ad hoc strategies resulting in failure to optimize fully cell growth coupled with desired product yield are explored. With the advancement of genomics and systems biology, a new paradigm toward systems metabolic engineering has been recognized. In particular, a genome-scale metabolic network reconstruction and modeling is a crucial systems-based tool for whole-cell-wide investigation and prediction. In this review, the cyanobacterial genome-scale metabolic models, which offer a system-level understanding of cyanobacterial metabolism, are described. The main process of metabolic network reconstruction and modeling of cyanobacteria are summarized. Strategies and developments on genome-scale network and modeling through the systems metabolic engineering approach are advanced and employed for efficient cyanobacterial-based biofuels production.
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Affiliation(s)
- Amornpan Klanchui
- Biological Engineering Program, Faculty of Engineering, King Mongkut's University of Technology Thonburi, Bangkok, 10140, Thailand
| | - Nachon Raethong
- Interdisciplinary Graduate Program in Bioscience, Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand
| | - Peerada Prommeenate
- Biochemical Engineering and Pilot Plant Research and Development (BEC) Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Wanwipa Vongsangnak
- Department of Zoology, Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand.,Computational Biomodelling Laboratory for Agricultural Science and Technology (CBLAST), Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand
| | - Asawin Meechai
- Department of Chemical Engineering, Faculty of Engineering, King Mongkut's University of Technology Thonburi, Bangkok, 10140, Thailand.
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25
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The sRNA NsiR4 is involved in nitrogen assimilation control in cyanobacteria by targeting glutamine synthetase inactivating factor IF7. Proc Natl Acad Sci U S A 2015; 112:E6243-52. [PMID: 26494284 DOI: 10.1073/pnas.1508412112] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Glutamine synthetase (GS), a key enzyme in biological nitrogen assimilation, is regulated in multiple ways in response to varying nitrogen sources and levels. Here we show a small regulatory RNA, NsiR4 (nitrogen stress-induced RNA 4), which plays an important role in the regulation of GS in cyanobacteria. NsiR4 expression in the unicellular Synechocystis sp. PCC 6803 and in the filamentous, nitrogen-fixing Anabaena sp. PCC 7120 is stimulated through nitrogen limitation via NtcA, the global transcriptional regulator of genes involved in nitrogen metabolism. NsiR4 is widely conserved throughout the cyanobacterial phylum, suggesting a conserved function. In silico target prediction, transcriptome profiling on pulse overexpression, and site-directed mutagenesis experiments using a heterologous reporter system showed that NsiR4 interacts with the 5'UTR of gifA mRNA, which encodes glutamine synthetase inactivating factor (IF)7. In Synechocystis, we observed an inverse relationship between the levels of NsiR4 and the accumulation of IF7 in vivo. This NsiR4-dependent modulation of gifA (IF7) mRNA accumulation influenced the glutamine pool and thus [Formula: see text] assimilation via GS. As a second target, we identified ssr1528, a hitherto uncharacterized nitrogen-regulated gene. Competition experiments between WT and an ΔnsiR4 KO mutant showed that the lack of NsiR4 led to decreased acclimation capabilities of Synechocystis toward oscillating nitrogen levels. These results suggest a role for NsiR4 in the regulation of nitrogen metabolism in cyanobacteria, especially for the adaptation to rapid changes in available nitrogen sources and concentrations. NsiR4 is, to our knowledge, the first identified bacterial sRNA regulating the primary assimilation of a macronutrient.
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26
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Shimura Y, Hirose Y, Misawa N, Osana Y, Katoh H, Yamaguchi H, Kawachi M. Comparison of the terrestrial cyanobacterium Leptolyngbya sp. NIES-2104 and the freshwater Leptolyngbya boryana PCC 6306 genomes. DNA Res 2015; 22:403-12. [PMID: 26494835 PMCID: PMC4675709 DOI: 10.1093/dnares/dsv022] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 08/31/2015] [Indexed: 11/13/2022] Open
Abstract
The cyanobacterial genus Leptolyngbya is widely distributed throughout terrestrial environments and freshwater. Because environmental factors, such as oxygen level, available water content, and light intensity, vary between soil surface and water bodies, terrestrial Leptolyngbya should have genomic differences with freshwater species to adapt to a land habitat. To study the genomic features of Leptolyngbya species, we determined the complete genome sequence of the terrestrial strain Leptolyngbya sp. NIES-2104 and compared it with that of the near-complete sequence of the freshwater Leptolyngbya boryana PCC 6306. The greatest differences between these two strains were the presence or absence of a nitrogen fixation gene cluster for anaerobic nitrogen fixation and several genes for tetrapyrrole synthesis, which can operate under micro-oxic conditions. These differences might reflect differences in oxygen levels where these strains live. Both strains have the genes for trehalose biosynthesis, but only Leptolyngbya sp. NIES-2104 has genetic capacity to produce a mycosporine-like amino acid, mycosporine-glycine. Mycosporine-glycine has an antioxidant action, which may contribute to adaptation to terrestrial conditions. These features of the genomes yielded additional insights into the classification and physiological characteristics of these strains.
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Affiliation(s)
- Yohei Shimura
- Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, Japan
| | - Yuu Hirose
- Department of Environmental and Life Sciences/Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology, Toyohashi, Aichi 441-8580, Japan
| | - Naomi Misawa
- Department of Environmental and Life Sciences/Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology, Toyohashi, Aichi 441-8580, Japan
| | - Yasunori Osana
- Department of Electrical and Electronics Engineering, University of Ryukyus, Nishihara, Okinawa 903-0213, Japan
| | - Hiroshi Katoh
- Life Science Research Center, Mie University, Tsu, Mie 514-8507, Japan
| | - Haruyo Yamaguchi
- Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, Japan
| | - Masanobu Kawachi
- Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, Japan
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Kopf M, Hess WR. Regulatory RNAs in photosynthetic cyanobacteria. FEMS Microbiol Rev 2015; 39:301-15. [PMID: 25934122 PMCID: PMC6596454 DOI: 10.1093/femsre/fuv017] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 01/06/2015] [Accepted: 03/10/2015] [Indexed: 12/02/2022] Open
Abstract
Regulatory RNAs play versatile roles in bacteria in the coordination of gene expression during various physiological processes, especially during stress adaptation. Photosynthetic bacteria use sunlight as their major energy source. Therefore, they are particularly vulnerable to the damaging effects of excess light or UV irradiation. In addition, like all bacteria, photosynthetic bacteria must adapt to limiting nutrient concentrations and abiotic and biotic stress factors. Transcriptome analyses have identified hundreds of potential regulatory small RNAs (sRNAs) in model cyanobacteria such as Synechocystis sp. PCC 6803 or Anabaena sp. PCC 7120, and in environmentally relevant genera such as Trichodesmium, Synechococcus and Prochlorococcus. Some sRNAs have been shown to actually contain μORFs and encode short proteins. Examples include the 40-amino-acid product of the sml0013 gene, which encodes the NdhP subunit of the NDH1 complex. In contrast, the functional characterization of the non-coding sRNA PsrR1 revealed that the 131 nt long sRNA controls photosynthetic functions by targeting multiple mRNAs, providing a paradigm for sRNA functions in photosynthetic bacteria. We suggest that actuatons comprise a new class of genetic elements in which an sRNA gene is inserted upstream of a coding region to modify or enable transcription of that region.
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Affiliation(s)
- Matthias Kopf
- Faculty of Biology, Institute of Biology III, University of Freiburg, D-79104 Freiburg, Germany
| | - Wolfgang R Hess
- Faculty of Biology, Institute of Biology III, University of Freiburg, D-79104 Freiburg, Germany
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28
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Kopf M, Klähn S, Scholz I, Hess WR, Voß B. Variations in the non-coding transcriptome as a driver of inter-strain divergence and physiological adaptation in bacteria. Sci Rep 2015; 5:9560. [PMID: 25902393 PMCID: PMC5386190 DOI: 10.1038/srep09560] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 03/05/2015] [Indexed: 12/16/2022] Open
Abstract
In all studied organisms, a substantial portion of the transcriptome consists of non-coding RNAs that frequently execute regulatory functions. Here, we have compared the primary transcriptomes of the cyanobacteria Synechocystis sp. PCC 6714 and PCC 6803 under 10 different conditions. These strains share 2854 protein-coding genes and a 16S rRNA identity of 99.4%, indicating their close relatedness. Conserved major transcriptional start sites (TSSs) give rise to non-coding transcripts within the sigB gene, from the 5′UTRs of cmpA and isiA, and 168 loci in antisense orientation. Distinct differences include single nucleotide polymorphisms rendering promoters inactive in one of the strains, e.g., for cmpR and for the asRNA PsbA2R. Based on the genome-wide mapped location, regulation and classification of TSSs, non-coding transcripts were identified as the most dynamic component of the transcriptome. We identified a class of mRNAs that originate by read-through from an sRNA that accumulates as a discrete and abundant transcript while also serving as the 5′UTR. Such an sRNA/mRNA structure, which we name ‘actuaton’, represents another way for bacteria to remodel their transcriptional network. Our findings support the hypothesis that variations in the non-coding transcriptome constitute a major evolutionary element of inter-strain divergence and capability for physiological adaptation.
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Affiliation(s)
- Matthias Kopf
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Stephan Klähn
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Ingeborg Scholz
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Wolfgang R Hess
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Björn Voß
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
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Los DA, Mironov KS. Modes of Fatty Acid desaturation in cyanobacteria: an update. Life (Basel) 2015; 5:554-67. [PMID: 25809965 PMCID: PMC4390868 DOI: 10.3390/life5010554] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 02/06/2015] [Accepted: 02/10/2015] [Indexed: 11/16/2022] Open
Abstract
Fatty acid composition of individual species of cyanobacteria is conserved and it may be used as a phylogenetic marker. The previously proposed classification system was based solely on biochemical data. Today, new genomic data are available, which support a need to update a previously postulated FA-based classification of cyanobacteria. These changes are necessary in order to adjust and synchronize biochemical, physiological and genomic data, which may help to establish an adequate comprehensive taxonomic system for cyanobacteria in the future. Here, we propose an update to the classification system of cyanobacteria based on their fatty acid composition.
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Affiliation(s)
- Dmitry A Los
- Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street, Moscow 127276, Russia.
| | - Kirill S Mironov
- Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street, Moscow 127276, Russia.
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30
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Salt acclimation of cyanobacteria and their application in biotechnology. Life (Basel) 2014; 5:25-49. [PMID: 25551682 PMCID: PMC4390839 DOI: 10.3390/life5010025] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 12/19/2014] [Indexed: 12/25/2022] Open
Abstract
The long evolutionary history and photo-autotrophic lifestyle of cyanobacteria has allowed them to colonize almost all photic habitats on Earth, including environments with high or fluctuating salinity. Their basal salt acclimation strategy includes two principal reactions, the active export of ions and the accumulation of compatible solutes. Cyanobacterial salt acclimation has been characterized in much detail using selected model cyanobacteria, but their salt sensing and regulatory mechanisms are less well understood. Here, we briefly review recent advances in the identification of salt acclimation processes and the essential genes/proteins involved in acclimation to high salt. This knowledge is of increasing importance because the necessary mass cultivation of cyanobacteria for future use in biotechnology will be performed in sea water. In addition, cyanobacterial salt resistance genes also can be applied to improve the salt tolerance of salt sensitive organisms, such as crop plants.
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31
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Finished Genome Sequence of the Unicellular Cyanobacterium Synechocystis sp. Strain PCC 6714. GENOME ANNOUNCEMENTS 2014; 2:2/4/e00757-14. [PMID: 25081267 PMCID: PMC4118070 DOI: 10.1128/genomea.00757-14] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Synechocystis sp. strain PCC 6714 is a unicellular cyanobacterium closely related to the popular model organism Synechocystis sp. strain PCC 6803. A combination of PacBio SMRT and Illumina GAIIx data results in a highly accurate finished genome sequence that provides a reliable resource for further comparative analyses.
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32
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Dempo Y, Ohta E, Nakayama Y, Bamba T, Fukusaki E. Molar-based targeted metabolic profiling of cyanobacterial strains with potential for biological production. Metabolites 2014; 4:499-516. [PMID: 24957038 PMCID: PMC4101518 DOI: 10.3390/metabo4020499] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 06/05/2014] [Accepted: 06/12/2014] [Indexed: 11/28/2022] Open
Abstract
Recently, cyanobacteria have become one of the most attractive hosts for biochemical production due to its high proliferative ability and ease of genetic manipulation. Several researches aimed at biological production using modified cyanobacteria have been reported previously. However, to improve the yield of bioproducts, a thorough understanding of the intercellular metabolism of cyanobacteria is necessary. Metabolic profiling techniques have proven to be powerful tools for monitoring cellular metabolism of various organisms and can be applied to elucidate the details of cyanobacterial metabolism. In this study, we constructed a metabolic profiling method for cyanobacteria using 13C-labeled cell extracts as internal standards. Using this method, absolute concentrations of 84 metabolites were successfully determined in three cyanobacterial strains which are commonly used as background strains for metabolic engineering. By comparing the differences in basic metabolic potentials of the three cyanobacterial strains, we found a well-correlated relationship between intracellular energy state and growth in cyanobacteria. By integrating our results with the previously reported biological production pathways in cyanobacteria, we found putative limiting step of carbon flux. The information obtained from this study will not only help gain insights in cyanobacterial physiology but also serve as a foundation for future metabolic engineering studies using cyanobacteria.
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Affiliation(s)
- Yudai Dempo
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Erika Ohta
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Yasumune Nakayama
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Takeshi Bamba
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Eiichiro Fukusaki
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
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33
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Kopf M, Klähn S, Scholz I, Matthiessen JKF, Hess WR, Voß B. Comparative analysis of the primary transcriptome of Synechocystis sp. PCC 6803. DNA Res 2014; 21:527-39. [PMID: 24935866 PMCID: PMC4195498 DOI: 10.1093/dnares/dsu018] [Citation(s) in RCA: 170] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
RNA-seq and especially differential RNA-seq-type transcriptomic analyses (dRNA-seq) are powerful analytical tools, as they not only provide insights into gene expression changes but also provide detailed information about all promoters active at a given moment, effectively giving a deep insight into the transcriptional landscape. Synechocystis sp. PCC 6803 (Synechocystis 6803) is a unicellular model cyanobacterium that is widely used in research fields from ecology, photophysiology to systems biology, modelling and biotechnology. Here, we analysed the response of the Synechocystis 6803 primary transcriptome to different, environmentally relevant stimuli. We established genome-wide maps of the transcriptional start sites active under 10 different conditions relevant for photosynthetic growth and identified 4,091 transcriptional units, which provide information about operons, 5′ and 3′ untranslated regions (UTRs). Based on a unique expression factor, we describe regulons and relevant promoter sequences at single-nucleotide resolution. Finally, we report several sRNAs with an intriguing expression pattern and therefore likely function, specific for carbon depletion (CsiR1), nitrogen depletion (NsiR4), phosphate depletion (PsiR1), iron stress (IsaR1) or photosynthesis (PsrR1). This dataset is accompanied by comprehensive information providing extensive visualization and data access to allow an easy-to-use approach for the design of experiments, the incorporation into modelling studies of the regulatory system and for comparative analyses.
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Affiliation(s)
- Matthias Kopf
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Stephan Klähn
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Ingeborg Scholz
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Jasper K F Matthiessen
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Wolfgang R Hess
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Björn Voß
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
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