1
|
Johnston IG. The Nitroplast and Its Relatives Support a Universal Model of Features Predicting Gene Retention in Endosymbiont and Organelle Genomes. Genome Biol Evol 2024; 16:evae132. [PMID: 38900924 PMCID: PMC11221429 DOI: 10.1093/gbe/evae132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 06/03/2024] [Accepted: 06/14/2024] [Indexed: 06/22/2024] Open
Abstract
Endosymbiotic relationships have shaped eukaryotic life. As endosymbionts coevolve with their host, toward full integration as organelles, their genomes tend to shrink, with genes being completely lost or transferred to the host nucleus. Modern endosymbionts and organelles show diverse patterns of gene retention, and why some genes and not others are retained in these genomes is not fully understood. Recent bioinformatic study has explored hypothesized influences on these evolutionary processes, finding that hydrophobicity and amino acid chemistry predict patterns of gene retention, both in organelles across eukaryotes and in less mature endosymbiotic relationships. The exciting ongoing elucidation of endosymbiotic relationships affords an independent set of instances to test this theory. Here, we compare the properties of retained genes in the nitroplast, recently reported to be an integrated organelle, two related cyanobacterial endosymbionts that form "spheroid bodies" in their host cells, and a range of other endosymbionts, with free-living relatives of each. We find that in each case, the symbiont's genome encodes proteins with higher hydrophobicity and lower amino pKa than their free-living relative, supporting the data-derived model predicting the retention propensity of genes across endosymbiont and organelle genomes.
Collapse
Affiliation(s)
- Iain G Johnston
- Department of Mathematics, University of Bergen, Bergen, Norway
- Computational Biology Unit, University of Bergen, Bergen, Norway
| |
Collapse
|
2
|
Du Z, Huang X, Wu H, Luo X. Tri-layered core-shell structured deferoxamine magnetic particles promote Microcystis aeruginosa growth. ENVIRONMENTAL RESEARCH 2024; 252:119062. [PMID: 38719066 DOI: 10.1016/j.envres.2024.119062] [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: 10/30/2023] [Revised: 04/21/2024] [Accepted: 04/30/2024] [Indexed: 05/12/2024]
Abstract
This experiment prepared magnetic composite siderophores (DMPs) with strong magnetism, excellent adsorption capacity, and high specific surface area. Exploring the synergistic effect of magnetic nanoparticles and siderophores on Microcystis aeruginosa growth under iron-deficient condition, by utilizing the characteristics of the three-layer core-shell structure of DMPs. This study elucidated the potential mechanism by which DMPs promote the cyanobacterial growth through physiological indicators and transcriptome analysis. On the experiment's final day, cell density in DMPs treatment group at 2, 4, and 8 mg/L were 1.10, 1.14 and 1.16 times higher than those in the control group (Ct), respectively. Similarly, chlorophyll and photosynthetic efficiency results showed improved algae growth with increasing DMPs dosage. The microcystin content in DMPs experimental groups at low, medium, and high concentration were 0.91, 0.86, and 0.83 times that of Ct, indicating alleviation of iron deficiency stress. Additionally, based on extracellular polymers, intracellular and extracellular siderophores, and visualization techniques, DMPs nanoparticles captured free iron sources in the environment, promoting algae growth by entering algal cells and facilitating the uptake and utilization of free iron ions from the solution. During the experiment, the iron uptake and transport genes (feoA and feoB) were significantly upregulated, whereas the algal siderophore synthesis gene (pchF) and the TonB-dependent transport system gene (TonB_C) were significantly downregulated, suggesting heightened activity in intracellular iron uptake and transport. This indicates an abundance of intracellular iron, eliminating the need for secrete siderophores to overcome iron deficiency. Microcystis aeruginosa increased iron bioavailability by using iron transported through DMPs in the environment while internalizing these DMPs. This study explored the mechanism of this synergistic effect to boost algal growth, and provided new ideas for elucidating the mechanism of cyanobacterial bloom outbreaks as well as the innovative application of biotechnology.
Collapse
Affiliation(s)
- Zunqing Du
- Department of Environmental Science and Engineering, Fudan University, Shanghai, China
| | - Xuhui Huang
- Department of Environmental Science and Engineering, Fudan University, Shanghai, China
| | - Hanqi Wu
- Department of Environmental Science and Engineering, Fudan University, Shanghai, China
| | - Xingzhang Luo
- Department of Environmental Science and Engineering, Fudan University, Shanghai, China.
| |
Collapse
|
3
|
Qiu GW, Zheng WC, Yang HM, Wang YY, Qi X, Huang D, Dai GZ, Shi H, Price NM, Qiu BS. Phosphorus deficiency alleviates iron limitation in Synechocystis cyanobacteria through direct PhoB-mediated gene regulation. Nat Commun 2024; 15:4426. [PMID: 38789507 PMCID: PMC11126600 DOI: 10.1038/s41467-024-48847-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 05/14/2024] [Indexed: 05/26/2024] Open
Abstract
Iron and phosphorus are essential nutrients that exist at low concentrations in surface waters and may be co-limiting resources for phytoplankton growth. Here, we show that phosphorus deficiency increases the growth of iron-limited cyanobacteria (Synechocystis sp. PCC 6803) through a PhoB-mediated regulatory network. We find that PhoB, in addition to its well-recognized role in controlling phosphate homeostasis, also regulates key metabolic processes crucial for iron-limited cyanobacteria, including ROS detoxification and iron uptake. Transcript abundances of PhoB-targeted genes are enriched in samples from phosphorus-depleted seawater, and a conserved PhoB-binding site is widely present in the promoters of the target genes, suggesting that the PhoB-mediated regulation may be highly conserved. Our findings provide molecular insights into the responses of cyanobacteria to simultaneous iron/phosphorus nutrient limitation.
Collapse
Affiliation(s)
- Guo-Wei Qiu
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Wen-Can Zheng
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Hao-Ming Yang
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Yu-Ying Wang
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Xing Qi
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Da Huang
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Guo-Zheng Dai
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Huazhong Shi
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, 79409, USA
| | - Neil M Price
- Department of Biology, McGill University, 1205 Docteur Penfield, Montreal, Québec, H3A 1B1, Canada
| | - Bao-Sheng Qiu
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China.
| |
Collapse
|
4
|
Schiksnis C, Xu M, Saito MA, McIlvin M, Moran D, Bian X, John SG, Zheng Q, Yang N, Fu F, Hutchins DA. Proteomics analysis reveals differential acclimation of coastal and oceanic Synechococcus to climate warming and iron limitation. Front Microbiol 2024; 15:1323499. [PMID: 38444803 PMCID: PMC10912551 DOI: 10.3389/fmicb.2024.1323499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 01/30/2024] [Indexed: 03/07/2024] Open
Abstract
In many oceanic regions, anthropogenic warming will coincide with iron (Fe) limitation. Interactive effects between warming and Fe limitation on phytoplankton physiology and biochemical function are likely, as temperature and Fe availability affect many of the same essential cellular pathways. However, we lack a clear understanding of how globally significant phytoplankton such as the picocyanobacteria Synechococcus will respond to these co-occurring stressors, and what underlying molecular mechanisms will drive this response. Moreover, ecotype-specific adaptations can lead to nuanced differences in responses between strains. In this study, Synechococcus isolates YX04-1 (oceanic) and XM-24 (coastal) from the South China Sea were acclimated to Fe limitation at two temperatures, and their physiological and proteomic responses were compared. Both strains exhibited reduced growth due to warming and Fe limitation. However, coastal XM-24 maintained relatively higher growth rates in response to warming under replete Fe, while its growth was notably more compromised under Fe limitation at both temperatures compared with YX04-1. In response to concurrent heat and Fe stress, oceanic YX04-1 was better able to adjust its photosynthetic proteins and minimize the generation of reactive oxygen species while reducing proteome Fe demand. Its intricate proteomic response likely enabled oceanic YX04-1 to mitigate some of the negative impact of warming on its growth during Fe limitation. Our study highlights how ecologically-shaped adaptations in Synechococcus strains even from proximate oceanic regions can lead to differing physiological and proteomic responses to these climate stressors.
Collapse
Affiliation(s)
- Cara Schiksnis
- Marine and Environmental Biology, University of Southern California, Los Angeles, CA, United States
| | - Min Xu
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Mak A. Saito
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Matthew McIlvin
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Dawn Moran
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Xiaopeng Bian
- Marine and Environmental Biology, University of Southern California, Los Angeles, CA, United States
| | - Seth G. John
- Marine and Environmental Biology, University of Southern California, Los Angeles, CA, United States
| | - Qiang Zheng
- State Key Laboratory of Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
| | - Nina Yang
- Marine and Environmental Biology, University of Southern California, Los Angeles, CA, United States
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
- Marine Policy Center, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Feixue Fu
- Marine and Environmental Biology, University of Southern California, Los Angeles, CA, United States
| | - David A. Hutchins
- Marine and Environmental Biology, University of Southern California, Los Angeles, CA, United States
| |
Collapse
|
5
|
Sun X, Xiao Y, Yong C, Sun H, Li S, Huang H, Jiang H. Interactions between the nitrogen-fixing cyanobacterium Trichodesmium and siderophore-producing cyanobacterium Synechococcus under iron limitation. ISME COMMUNICATIONS 2024; 4:ycae072. [PMID: 38873030 PMCID: PMC11171426 DOI: 10.1093/ismeco/ycae072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 04/07/2024] [Indexed: 06/15/2024]
Abstract
As diazotrophic cyanobacteria of tremendous biomass, Trichodesmium continuously provide a nitrogen source for carbon-fixing cyanobacteria and drive the generation of primary productivity in marine environments. However, ocean iron deficiencies limit growth and metabolism of Trichodesmium. Recent studies have shown the co-occurrence of Trichodesmium and siderophore-producing Synechococcus in iron-deficient oceans, but whether siderophores secreted by Synechococcus can be used by Trichodesmium to adapt to iron deficiency is not clear. We constructed a mutant Synechococcus strain unable to produce siderophores to explore this issue. Synechococcus filtrates with or without siderophores were added into a Trichodesmium microbial consortium consisting of Trichodesmium erythraeum IMS 101 as the dominant microbe with chronic iron deficiency. By analyzing the physiological phenotype, metagenome, and metatranscriptome, we investigated the interactions between the nitrogen-fixing cyanobacterium Tricodesmium and siderophore-producing cyanobacterium Synechococcus under conditions of iron deficiency. The results indicated that siderophores secreted by Synechococcus are likely to chelate with free iron in the culture medium of the Trichodesmium consortium, reducing the concentration of bioavailable iron and posing greater challenges to the absorption of iron by Trichodesmium. These findings revealed the characteristics of iron-competitive utilization between diazotrophic cyanobacteria and siderophore-producing cyanobacteria, as well as potential interactions, and provide a scientific basis for understanding the regulatory effects of nutrient limitation on marine primary productivity.
Collapse
Affiliation(s)
- Xumei Sun
- School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang, 315211, People’s Republic of China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), 1 Jintang Road, Zhuhai, Guangdong, 519000, People’s Republic of China
| | - Yan Xiao
- School of Life Sciences, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, People’s Republic of China
| | - Chengwen Yong
- School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang, 315211, People’s Republic of China
| | - Hansheng Sun
- School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang, 315211, People’s Republic of China
| | - Shuangqing Li
- School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang, 315211, People’s Republic of China
| | - Hailong Huang
- School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang, 315211, People’s Republic of China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), 1 Jintang Road, Zhuhai, Guangdong, 519000, People’s Republic of China
| | - Haibo Jiang
- School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang, 315211, People’s Republic of China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), 1 Jintang Road, Zhuhai, Guangdong, 519000, People’s Republic of China
- School of Life Sciences, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, People’s Republic of China
| |
Collapse
|
6
|
Müller B. Iron transport mechanisms and their evolution focusing on chloroplasts. JOURNAL OF PLANT PHYSIOLOGY 2023; 288:154059. [PMID: 37586271 DOI: 10.1016/j.jplph.2023.154059] [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: 01/23/2023] [Revised: 07/26/2023] [Accepted: 07/28/2023] [Indexed: 08/18/2023]
Abstract
Iron (Fe) is an essential element for photosynthetic organisms, required for several vital biological functions. Photosynthesis, which takes place in the chloroplasts of higher plants, is the major Fe consumer. Although the components of the root Fe uptake system in dicotyledonous and monocotyledonous plants have been extensively studied, the Fe transport mechanisms of chloroplasts in these two groups of plants have received little attention. This review focuses on the comparative analysis of Fe transport processes in the evolutionary ancestors of chloroplasts (cyanobacteria) with the processes in embryophytes and green algae (Viridiplantae). The aim is to summarize how chloroplasts are integrated into cellular Fe homeostasis and how Fe transporters and Fe transport mechanisms have been modified by evolution.
Collapse
Affiliation(s)
- Brigitta Müller
- Department of Plant Physiology and Molecular Biology, Institute of Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/C, Budapest, H-1117, Hungary.
| |
Collapse
|
7
|
Lin S, Li S, Ouyang T, Chen G. Site-2 Protease Slr1821 Regulates Carbon/Nitrogen Homeostasis during Ammonium Stress Acclimation in Cyanobacterium Synechocystis sp. PCC 6803. Int J Mol Sci 2023; 24:ijms24076606. [PMID: 37047577 PMCID: PMC10094980 DOI: 10.3390/ijms24076606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 03/25/2023] [Accepted: 03/27/2023] [Indexed: 04/05/2023] Open
Abstract
Excess ammonium imposes toxicity and stress response in cyanobacteria. How cyanobacteria acclimate to NH4+ stress is so far poorly understood. Here, Synechocystis sp. PCC6803 S2P homolog Slr1821 was identified as the essential regulator through physiological characterization and transcriptomic analysis of its knockout mutant. The proper expression of 60% and 67% of the NH4+ activated and repressed genes, respectively, were actually Slr1821-dependent since they were abolished or reversed in ∆slr1821. Synechocystis 6803 suppressed nitrogen uptake and assimilation, ammonium integration and mobilization of other nitrogen sources upon NH4+ stress. Opposite regulation on genes for assimilation of nitrogen and carbon, such as repression of nitrogen regulatory protein PII, PII interactive protein PirC and activation of carbon acquisition regulator RcbR, demonstrated that Synechocystis 6803 coordinated regulation to maintain carbon/nitrogen homeostasis under increasing nitrogen, while functional Slr1821 was indispensable for most of this coordinated regulation. Additionally, slr1821 knockout disrupted the proper response of regulators and transporters in the ammonium-specific stimulon, and resulted in defective photosynthesis as well as compromised translational and transcriptional machinery. These results provide new insight into the coordinated regulation of nutritional fluctuation and the functional characterization of S2Ps. They also provide new targets for bioengineering cyanobacteria in bioremediation and improving ammonium tolerance in crop plants.
Collapse
Affiliation(s)
- Shiqi Lin
- School of Food Sciences and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou 510641, China
| | - Shiliang Li
- School of Food Sciences and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou 510641, China
| | - Tong Ouyang
- School of Food Sciences and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou 510641, China
| | - Gu Chen
- School of Food Sciences and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou 510641, China
| |
Collapse
|
8
|
Diversity and Evolution of Iron Uptake Pathways in Marine Cyanobacteria from the Perspective of the Coastal Strain Synechococcus sp. Strain PCC 7002. Appl Environ Microbiol 2023; 89:e0173222. [PMID: 36533965 PMCID: PMC9888192 DOI: 10.1128/aem.01732-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Marine cyanobacteria contribute to approximately half of the ocean primary production, and their biomass is limited by low iron (Fe) bioavailability in many regions of the open seas. The mechanisms by which marine cyanobacteria overcome Fe limitation remain unclear. In this study, multiple Fe uptake pathways have been identified in a coastal strain of Synechococcus sp. strain PCC 7002. A total of 49 mutants were obtained by gene knockout methods, and 10 mutants were found to have significantly decreased growth rates compared to the wild type (WT). The genes related to active Fe transport pathways such as TonB-dependent transporters and the synthesis and secretion of siderophores are found to be essential for the adaptation of Fe limitation in Synechococcus sp. PCC 7002. By comparing the Fe uptake pathways of this coastal strain with other open-ocean cyanobacterial strains, it can be concluded that the Fe uptake strategies from different cyanobacteria have a strong relationship with the Fe bioavailability in their habitats. The evolution and adaptation of cyanobacterial iron acquisition strategies with the change of iron environments from ancient oceans to modern oceans are discussed. This study provides new insights into the diversified strategies of marine cyanobacteria in different habitats from temporal and spatial scales. IMPORTANCE Iron (Fe) is an important limiting factor of marine primary productivity. Cyanobacteria, the oldest photosynthetic oxygen-evolving organisms on the earth, play crucial roles in marine primary productivity, especially in the oligotrophic ocean. How they overcome Fe limitation during the long-term evolution process has not been fully revealed. Fe uptake mechanisms of cyanobacteria have been partially studied in freshwater cyanobacteria but are largely unknown in marine cyanobacterial species. In this paper, the characteristics of Fe uptake mechanisms in a coastal model cyanobacterium, Synechococcus sp. PCC 7002, were studied. Furthermore, the relationship between Fe uptake strategies and Fe environments of cyanobacterial habitats has been revealed from temporal and spatial scales, which provides a good case for marine microorganisms adapting to changes in the marine environment.
Collapse
|
9
|
Isani G, Ferlizza E, Bertocchi M, Dalmonte T, Menotta S, Fedrizzi G, Andreani G. Iron Content, Iron Speciation and Phycocyanin in Commercial Samples of Arthrospira spp. Int J Mol Sci 2022; 23:ijms232213949. [PMID: 36430428 PMCID: PMC9698952 DOI: 10.3390/ijms232213949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/05/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
Cyanobacteria are characterized by high iron content. In this research, we collected ten commercial samples of Arthrospira spp. sold as food supplement to determine iron content and assess whether iron speciation showed variability among samples and changed respect to A. platensis grown in controlled conditions. Particular attention was also paid to phycocyanin, as an iron-binding protein. In six of the ten samples, 14 essential and non-essential trace elements were analysed using ICP-MS. Iron content measured in samples using atomic absorption spectrometry (AAS) varied from 353 (sample S5) to 1459 (sample S7) µg g-1 dry weight and was in the range of those reported by other authors in commercial supplements. Iron speciation was studied using size exclusion chromatography followed by the analysis of the collected fraction for the determination of iron by AAS and for protein separation using SDS-PAGE. Overlapping chromatographic profiles were obtained for total proteins, phycocyanin and iron, although quantitative differences were evidenced among the samples analysed. In most samples, iron was mainly bound to ligands with high molecular mass; however, in four samples iron was also bound to ligands with low molecular mass. In fractions containing the most relevant iron burden, the principal protein was phycocyanin, confirming its role as an iron-binding protein in commercial samples.
Collapse
Affiliation(s)
- Gloria Isani
- Department of Veterinary Medical Sciences, Alma Mater Studiorum, University of Bologna, Via Tolara di sopra 50, 40064 Ozzano dell’Emilia, Italy
| | - Enea Ferlizza
- Department of Experimental, Diagnostic and Specialty Medicine, Alma Mater Studiorum, University of Bologna, Via Belmeloro 8, 40126 Bologna, Italy
- Correspondence:
| | - Martina Bertocchi
- Department of Veterinary Medical Sciences, Alma Mater Studiorum, University of Bologna, Via Tolara di sopra 50, 40064 Ozzano dell’Emilia, Italy
| | - Thomas Dalmonte
- Department of Veterinary Medical Sciences, Alma Mater Studiorum, University of Bologna, Via Tolara di sopra 50, 40064 Ozzano dell’Emilia, Italy
| | - Simonetta Menotta
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna, Chemical Department, Via P. Fiorini 5, 40127 Bologna, Italy
| | - Giorgio Fedrizzi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia Romagna, Chemical Department, Via P. Fiorini 5, 40127 Bologna, Italy
| | - Giulia Andreani
- Department of Veterinary Medical Sciences, Alma Mater Studiorum, University of Bologna, Via Tolara di sopra 50, 40064 Ozzano dell’Emilia, Italy
| |
Collapse
|
10
|
Enzingmüller-Bleyl TC, Boden JS, Herrmann AJ, Ebel KW, Sánchez-Baracaldo P, Frankenberg-Dinkel N, Gehringer MM. On the trail of iron uptake in ancestral Cyanobacteria on early Earth. GEOBIOLOGY 2022; 20:776-789. [PMID: 35906866 DOI: 10.1111/gbi.12515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/28/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
Cyanobacteria oxygenated Earth's atmosphere ~2.4 billion years ago, during the Great Oxygenation Event (GOE), through oxygenic photosynthesis. Their high iron requirement was presumably met by high levels of Fe(II) in the anoxic Archean environment. We found that many deeply branching Cyanobacteria, including two Gloeobacter and four Pseudanabaena spp., cannot synthesize the Fe(II) specific transporter, FeoB. Phylogenetic and relaxed molecular clock analyses find evidence that FeoB and the Fe(III) transporters, cFTR1 and FutB, were present in Proterozoic, but not earlier Archaean lineages of Cyanobacteria. Furthermore Pseudanabaena sp. PCC7367, an early diverging marine, benthic strain grown under simulated Archean conditions, constitutively expressed cftr1, even after the addition of Fe(II). Our genetic profiling suggests that, prior to the GOE, ancestral Cyanobacteria may have utilized alternative metal iron transporters such as ZIP, NRAMP, or FicI, and possibly also scavenged exogenous siderophore bound Fe(III), as they only acquired the necessary Fe(II) and Fe(III) transporters during the Proterozoic. Given that Cyanobacteria arose 3.3-3.6 billion years ago, it is possible that limitations in iron uptake may have contributed to the delay in their expansion during the Archean, and hence the oxygenation of the early Earth.
Collapse
Affiliation(s)
| | - Joanne S Boden
- School of Geographical Sciences, Faculty of Science, University of Bristol, Bristol, UK
- School of Earth and Environmental Sciences, University of St. Andrews, St. Andrews, UK
| | - Achim J Herrmann
- Department of Microbiology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Katharina W Ebel
- Department of Microbiology, University of Kaiserslautern, Kaiserslautern, Germany
| | | | | | - Michelle M Gehringer
- Department of Microbiology, University of Kaiserslautern, Kaiserslautern, Germany
| |
Collapse
|
11
|
Gilbert NE, LeCleir GR, Strzepek RF, Ellwood MJ, Twining BS, Roux S, Pennacchio C, Boyd PW, Wilhelm SW. Bioavailable iron titrations reveal oceanic Synechococcus ecotypes optimized for different iron availabilities. ISME COMMUNICATIONS 2022; 2:54. [PMID: 37938659 PMCID: PMC9723758 DOI: 10.1038/s43705-022-00132-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 05/24/2022] [Accepted: 06/09/2022] [Indexed: 04/18/2023]
Abstract
The trace metal iron (Fe) controls the diversity and activity of phytoplankton across the surface oceans, a paradigm established through decades of in situ and mesocosm experimental studies. Despite widespread Fe-limitation within high-nutrient, low chlorophyll (HNLC) waters, significant contributions of the cyanobacterium Synechococcus to the phytoplankton stock can be found. Correlations among differing strains of Synechococcus across different Fe-regimes have suggested the existence of Fe-adapted ecotypes. However, experimental evidence of high- versus low-Fe adapted strains of Synechococcus is lacking, and so we investigated the transcriptional responses of microbial communities inhabiting the HNLC, sub-Antarctic region of the Southern Ocean during the Spring of 2018. Analysis of metatranscriptomes generated from on-deck incubation experiments reflecting a gradient of Fe-availabilities reveal transcriptomic signatures indicative of co-occurring Synechococcus ecotypes adapted to differing Fe-regimes. Functional analyses comparing low-Fe and high-Fe conditions point to various Fe-acquisition mechanisms that may allow persistence of low-Fe adapted Synechococcus under Fe-limitation. Comparison of in situ surface conditions to the Fe-titrations indicate ecological relevance of these mechanisms as well as persistence of both putative ecotypes within this region. This Fe-titration approach, combined with transcriptomics, highlights the short-term responses of the in situ phytoplankton community to Fe-availability that are often overlooked by examining genomic content or bulk physiological responses alone. These findings expand our knowledge about how phytoplankton in HNLC Southern Ocean waters adapt and respond to changing Fe supply.
Collapse
Affiliation(s)
- Naomi E Gilbert
- Department of Microbiology, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Gary R LeCleir
- Department of Microbiology, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Robert F Strzepek
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7004, Australia
- Australian Antarctic Program Partnership (AAPP), Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7004, Australia
| | - Michael J Ellwood
- Research School of Earth Sciences, Australian National University, Canberra, ACT, Australia
| | | | - S Roux
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - C Pennacchio
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Philip W Boyd
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7004, Australia
| | - Steven W Wilhelm
- Department of Microbiology, The University of Tennessee, Knoxville, TN, 37996, USA.
| |
Collapse
|
12
|
Lima S, Matinha-Cardoso J, Giner-Lamia J, Couto N, Pacheco CC, Florencio FJ, Wright PC, Tamagnini P, Oliveira P. Extracellular vesicles as an alternative copper-secretion mechanism in bacteria. JOURNAL OF HAZARDOUS MATERIALS 2022; 431:128594. [PMID: 35259694 DOI: 10.1016/j.jhazmat.2022.128594] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 02/18/2022] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
Metal homeostasis is fundamental for optimal performance of cell metabolic pathways. Over the course of evolution, several systems emerged to warrant an intracellular metal equilibrium. When exposed to growth-challenging copper concentrations, Gram-negative bacteria quickly activate copper-detoxification mechanisms, dependent on transmembrane-protein complexes and metallochaperones that mediate metal efflux. Here, we show that vesiculation is also a common bacterial response mechanism to high copper concentrations, and that extracellular vesicles (EVs) play a role in transporting copper. We present evidence that bacteria from different ecological niches release copious amounts of EVs when exposed to copper. Along with the activation of the classical detoxification systems, we demonstrate that copper-stressed cells of the cyanobacterium Synechocystis sp. PCC6803 release EVs loaded with the copper-binding metallochaperone CopM. Under standard growth conditions, CopM-loaded EVs could also be isolated from a Synechocystis strain lacking a functional TolC-protein, which we characterize here as exhibiting a copper-sensitive phenotype. Analyses of Synechocystis tolC-mutant's EVs isolated from cells cultivated under standard conditions indicated the presence of copper therein, in significantly higher levels as compared to those from the wild-type. Altogether, these results suggest that release of EVs in bacteria represent a novel copper-secretion mechanism, shedding light into alternative mechanisms of bacterial metal resistance.
Collapse
Affiliation(s)
- Steeve Lima
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; MCbiology Doctoral Program, ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Jorge Matinha-Cardoso
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
| | - Joaquín Giner-Lamia
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC C, Américo Vespucio, 49, 41092 Sevilla, Spain; Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Parque Científico y Tecnológico, UPM Campus de Montegancedo, Ctra, M-40, km 38, 28223 Madrid, Spain; Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid (UPM), Campus, Av. Puerta de Hierro, nº 2, 4, 28040 Madrid, Spain
| | - Narciso Couto
- Department of Chemical and Biological Engineering, University of Sheffield, Mappin St, Sheffield City Centre, Sheffield S1 4NL, United Kingdom
| | - Catarina C Pacheco
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
| | - Francisco J Florencio
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC C, Américo Vespucio, 49, 41092 Sevilla, Spain; Departamento de Bioquímica Vegetal y Biología Molecular, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes s/n, 41012 Sevilla, Spain
| | - Phillip C Wright
- University of Southampton, Office of the President and Vice Chancellor B37, University Rd, Highfield, Southampton SO17 1BJ, United Kingdom
| | - Paula Tamagnini
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal
| | - Paulo Oliveira
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
| |
Collapse
|
13
|
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]
|
14
|
Iron Speciation and Iron Binding Proteins in Arthrospira platensis Grown in Media Containing Different Iron Concentrations. Int J Mol Sci 2022; 23:ijms23116283. [PMID: 35682960 PMCID: PMC9181241 DOI: 10.3390/ijms23116283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 05/31/2022] [Accepted: 06/02/2022] [Indexed: 01/27/2023] Open
Abstract
Cyanobacteria are characterized by high iron content. This study investigated the effects of varying iron concentrations (1, 5, and 10 mg L-1) in the culture media on the biochemical composition and the iron bioaccumulation and speciation in Arthrospira platensis F&M-C256. Iron content measured in biomasses varied from 0.35 to 2.34 mg g-1 dry weight depending on the iron concentration in the culture media. These biomasses can be considered of interest for the production of spirulina-based supplements with low and high iron content. Iron speciation was studied using size exclusion chromatography followed by atomic absorption spectrometry and proteomic analysis. The role of C-phycocyanin as an iron binding protein was also investigated. Overall, the present results provide a better understanding of iron metabolism in cyanobacteria and a foundation for further studies.
Collapse
|
15
|
de Vries S, de Vries J. Evolutionary genomic insights into cyanobacterial symbioses in plants. QUANTITATIVE PLANT BIOLOGY 2022; 3:e16. [PMID: 37077989 PMCID: PMC10095879 DOI: 10.1017/qpb.2022.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 02/03/2022] [Accepted: 02/07/2022] [Indexed: 05/03/2023]
Abstract
Photosynthesis, the ability to fix atmospheric carbon dioxide, was acquired by eukaryotes through symbiosis: the plastids of plants and algae resulted from a cyanobacterial symbiosis that commenced more than 1.5 billion years ago and has chartered a unique evolutionary path. This resulted in the evolutionary origin of plants and algae. Some extant land plants have recruited additional biochemical aid from symbiotic cyanobacteria; these plants associate with filamentous cyanobacteria that fix atmospheric nitrogen. Examples of such interactions can be found in select species from across all major lineages of land plants. The recent rise in genomic and transcriptomic data has provided new insights into the molecular foundation of these interactions. Furthermore, the hornwort Anthoceros has emerged as a model system for the molecular biology of cyanobacteria-plant interactions. Here, we review these developments driven by high-throughput data and pinpoint their power to yield general patterns across these diverse symbioses.
Collapse
Affiliation(s)
- Sophie de Vries
- Department of Applied Bioinformatics, Institute for Microbiology and Genetics, University of Goettingen, Goettingen, Germany
- Authors for correspondence: Sophie de Vries E-mail: Jan de Vries E-mail:
| | - Jan de Vries
- Department of Applied Bioinformatics, Institute for Microbiology and Genetics, University of Goettingen, Goettingen, Germany
- Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, Goettingen, Germany
- Campus Institute Data Science (CIDAS), University of Goettingen, Goettingen, Germany
- Authors for correspondence: Sophie de Vries E-mail: Jan de Vries E-mail:
| |
Collapse
|
16
|
Cardoso D, Lima S, Matinha-Cardoso J, Tamagnini P, Oliveira P. The Role of Outer Membrane Protein(s) Harboring SLH/OprB-Domains in Extracellular Vesicles’ Production in Synechocystis sp. PCC 6803. PLANTS 2021; 10:plants10122757. [PMID: 34961227 PMCID: PMC8707739 DOI: 10.3390/plants10122757] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/04/2021] [Accepted: 12/09/2021] [Indexed: 01/07/2023]
Abstract
Cyanobacteria are a group of photosynthetic prokaryotes that contribute to primary production on a global scale. These microorganisms release vesicles to the extracellular environment, spherical nanosized structures, derived essentially from the outer membrane. Even though earlier works in model Gram-negative bacteria have hypothesized that outer membrane stability is crucial in vesicle formation, the mechanisms determining vesicle biogenesis in cyanobacteria remain unknown. Here, we report on the identification of six candidate genes encoding outer membrane proteins harboring SLH/OprB-domains in the genome of the model cyanobacterium Synechocystis sp. PCC 6803. Using a genetics-based approach, one gene was found to encode an essential protein (Slr1841), while the remaining five are not essential for growth under standard conditions. Vesicle production was monitored, and it was found that a mutant in the gene encoding the second most abundant SLH/OprB protein in Synechocystis sp. PCC 6803 outer membrane (Slr1908) produces more vesicles than any of the other tested strains. Moreover, the Slr1908-protein was also found to be important for iron uptake. Altogether, our results suggest that proteins containing the SLH/OprB-domains may have dual biological role, related to micronutrient uptake and to outer membrane stability, which, together or alone, seem to be involved in cyanobacterial vesicle biogenesis.
Collapse
Affiliation(s)
- Delfim Cardoso
- MABBS—Mestrado em Aplicações em Biotecnologia e Biologia Sintética, Faculdade de Ciências, Universidade do Porto, R. Campo Alegre s/n, 4169-007 Porto, Portugal;
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal; (S.L.); (J.M.-C.); (P.T.)
- IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Steeve Lima
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal; (S.L.); (J.M.-C.); (P.T.)
- IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
- MCbiology Doctoral Program, ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, R. Jorge de Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Jorge Matinha-Cardoso
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal; (S.L.); (J.M.-C.); (P.T.)
- IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Paula Tamagnini
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal; (S.L.); (J.M.-C.); (P.T.)
- IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, R. Campo Alegre s/n, 4169-007 Porto, Portugal
| | - Paulo Oliveira
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal; (S.L.); (J.M.-C.); (P.T.)
- IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, R. Campo Alegre s/n, 4169-007 Porto, Portugal
- Correspondence: ; Tel.: +351-22-607-4900
| |
Collapse
|
17
|
Sengupta S, Sahasrabuddhe D, Wangikar PP. Transporter engineering for the development of cyanobacteria as cell factories: A text analytics guided survey. Biotechnol Adv 2021; 54:107816. [PMID: 34411662 DOI: 10.1016/j.biotechadv.2021.107816] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 08/10/2021] [Accepted: 08/13/2021] [Indexed: 11/28/2022]
Abstract
Cyanobacteria are attractive candidates for photoautotrophic production of platform chemicals due to their inherent ability to utilize carbon dioxide as the sole carbon source. Metabolic pathways can be engineered more readily in cyanobacteria compared to higher photosynthetic organisms. Although significant progress has been made in pathway engineering, intracellular accumulation of the product is a potential bottleneck in large-scale production. Likewise, substrate uptake is known to limit growth and product formation. These limitations can potentially be addressed by targeted and controlled expression of transporter proteins in the metabolically engineered strains. This review focuses on the transporters that have been explored in cyanobacteria. To highlight the progress on characterization and application of cyanobacterial transporters, we applied text analytics to extract relevant information from over 1000 publications. We have categorized the transporters based on their source, their function and the solute they transport. Further, the review provides insights into the potential of transporters in the metabolic engineering of cyanobacteria for improved product titer.
Collapse
Affiliation(s)
- Shinjinee Sengupta
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India; DBT-Pan IIT Center for Bioenergy, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Deepti Sahasrabuddhe
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India; DBT-Pan IIT Center for Bioenergy, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India; Wadhwani Research Center for Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Pramod P Wangikar
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India; DBT-Pan IIT Center for Bioenergy, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India; Wadhwani Research Center for Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
| |
Collapse
|
18
|
Iron transport in cyanobacteria - from molecules to communities. Trends Microbiol 2021; 30:229-240. [PMID: 34175176 DOI: 10.1016/j.tim.2021.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/01/2021] [Accepted: 06/01/2021] [Indexed: 11/22/2022]
Abstract
Iron is an essential micronutrient for the ecologically important photoautotrophic cyanobacteria which are found across diverse aquatic environments. Low concentrations and poor bioavailability of certain iron species exert a strong control on cyanobacterial growth, affecting ecosystem structure and biogeochemical cycling. Here, we review the iron-acquisition pathways cyanobacteria utilize for overcoming these challenges. As the molecular details of cyanobacterial iron transport are being uncovered, an overall scheme of how cyanobacteria handle and exploit this scarce and redox-active micronutrient is emerging. Importantly, the range of biological solutions used by cyanobacteria to increase iron fluxes goes beyond transport and includes behavioral traits of colonial cyanobacteria and intricate cyanobacteria-bacteria interactions.
Collapse
|
19
|
Schätzle H, Brouwer EM, Liebhart E, Stevanovic M, Schleiff E. Comparative Phenotypic Analysis of Anabaena sp. PCC 7120 Mutants of Porinlike Genes. J Microbiol Biotechnol 2021; 31:645-658. [PMID: 33879642 PMCID: PMC9705863 DOI: 10.4014/jmb.2103.03009] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/05/2021] [Accepted: 04/06/2021] [Indexed: 12/15/2022]
Abstract
Porins are essential for the viability of Gram-negative bacteria. They ensure the uptake of nutrients, can be involved in the maintenance of outer membrane integrity and define the antibiotic or drug resistance of organisms. The function and structure of porins in proteobacteria is well described, while their function in photoautotrophic cyanobacteria has not been systematically explored. We compared the domain architecture of nine putative porins in the filamentous cyanobacterium Anabaena sp. PCC 7120 and analyzed the seven candidates with predicted OprB-domain. Single recombinant mutants of the seven genes were created and their growth capacity under different conditions was analyzed. Most of the putative porins seem to be involved in the transport of salt and copper, as respective mutants were resistant to elevated concentrations of these substances. In turn, only the mutant of alr2231 was less sensitive to elevated zinc concentrations, while mutants of alr0834, alr4741 and all4499 were resistant to high manganese concentrations. Notably the mutant of alr4550 shows a high sensitivity against harmful compounds, which is indicative for a function related to the maintenance of outer membrane integrity. Moreover, the mutant of all5191 exhibited a phenotype which suggests either a higher nitrate demand or an inefficient nitrogen fixation. The dependency of porin membrane insertion on Omp85 proteins was tested exemplarily for Alr4550, and an enhanced aggregation of Alr4550 was observed in two omp85 mutants. The comparative analysis of porin mutants suggests that the proteins in parts perform distinct functions related to envelope integrity and solute uptake.
Collapse
Affiliation(s)
- Hannah Schätzle
- Institute for Molecular Biosciences, Goethe University, Frankfurt am Main, Germany,FIERCE, Goethe University, Frankfurt am Main, Germany,Buchmann Institute for Molecular Life Sciences, Goethe University, Frankfurt am Main, Germany
| | - Eva-Maria Brouwer
- Institute for Molecular Biosciences, Goethe University, Frankfurt am Main, Germany
| | - Elisa Liebhart
- Institute for Molecular Biosciences, Goethe University, Frankfurt am Main, Germany
| | - Mara Stevanovic
- Institute for Molecular Biosciences, Goethe University, Frankfurt am Main, Germany
| | - Enrico Schleiff
- Institute for Molecular Biosciences, Goethe University, Frankfurt am Main, Germany,FIERCE, Goethe University, Frankfurt am Main, Germany,Buchmann Institute for Molecular Life Sciences, Goethe University, Frankfurt am Main, Germany,Frankfurt Institute of Advanced Studies, Frankfurt am Main, Germany,Corresponding author Phone: +49 69 798 29287 Fax: +49 69 798 29286 E-mail:
| |
Collapse
|
20
|
Liu LM, Li DL, Deng B, Wang XW, Jiang HB. Special roles for efflux systems in iron homeostasis of non-siderophore-producing cyanobacteria. Environ Microbiol 2021; 24:551-565. [PMID: 33817959 DOI: 10.1111/1462-2920.15506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 04/03/2021] [Indexed: 11/28/2022]
Abstract
In oligotrophic oceans, low bioavailability of Fe is a key factor limiting primary productivity. However, excessive Fe in cells leads to the Fenton reaction, which is toxic to cells. Cyanobacteria must strictly maintain intracellular Fe homeostasis. Here, we knocked out a series of genes encoding efflux systems in Synechocystis sp. PCC 6803, and found eight genes that are required for high Fe detoxification. Unexpectedly, the HlyBD-TolC efflux system plays an important role in the adaptation of Synechocystis under Fe-deficient conditions. Mutants of HlyD and TolC grew worse than the wild-type strain under low-Fe conditions and showed significantly lower intracellular Fe contents than the wild-type strain. We excluded the possibility that the low Fe sensitivity of the HlyBD-TolC mutants was caused by a loss of the S-layer, the main extracellular protein secreted via this efflux system. Inactivation of the HlyD protein influenced type IV pili formation and direct inactivation of type IV pili related genes affected the adaptation to low-Fe conditions. HlyBD-TolC system is likely involved in the formation of type IV pili and indirectly influenced Fe acquisition. Our findings suggest that efflux system in non-siderophore-producing cyanobacteria can facilitate Fe uptake and help cells adapt to Fe-deficient conditions via novel pathways.
Collapse
Affiliation(s)
- Ling-Mei Liu
- School of Life Sciences, Central China Normal University, Wuhan, Hubei, 430079, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, 519080, China
| | - Ding-Lan Li
- School of Life Sciences, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Bin Deng
- School of Life Sciences, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Xin-Wei Wang
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, 519080, China.,School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, 315211, China
| | - Hai-Bo Jiang
- School of Life Sciences, Central China Normal University, Wuhan, Hubei, 430079, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, 519080, China.,School of Marine Sciences, Ningbo University, Ningbo, Zhejiang, 315211, China
| |
Collapse
|
21
|
Qiu GW, Lis H, Qiu BS, Keren N. Long-term iron deprivation and subsequent recovery uncover heterogeneity in the response of cyanobacterial populations. Environ Microbiol 2021; 23:1793-1804. [PMID: 33615658 DOI: 10.1111/1462-2920.15443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/15/2021] [Accepted: 02/20/2021] [Indexed: 11/29/2022]
Abstract
Cyanobacteria are globally important primary producers and nitrogen fixers. They are frequently limited by iron bioavailability in natural environments that often fluctuate due to rapid consumption and irregular influx of external Fe. Here we identify a succession of physiological changes in Synechocystis sp. PCC 6803 occurring over 14-16 days of iron deprivation and subsequent recovery. We observe several adaptive strategies that allow cells to push their metabolic limits under the restriction of declining intracellular Fe quotas. Interestingly, cyanobacterial populations exposed to prolonged iron deprivation showed discernible heterogeneity in cellular auto-fluorescence during the recovery process. Using FACS and microscopy techniques we revealed that only cells with high auto-fluorescence were able to grow and reconstitute thylakoid membranes. We propose that ROS-mediated damage is likely to be associated with the emergence of the two subpopulations, and, indeed, a rapid increase in intracellular ROS content was observed during the first hours following iron addition to Fe-starved cultures. These results suggest that an increasing iron supply is a double-edged sword - posing both an opportunity and a risk. Therefore, phenotypic heterogeneity within populations is crucial for the survival and proliferation of organisms facing iron fluctuations within natural environments.
Collapse
Affiliation(s)
- Guo-Wei Qiu
- Department of Plant and Environmental Sciences, Edmond J. Safra Campus, The Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem, 9190402, Israel.,School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Hagar Lis
- Department of Plant and Environmental Sciences, Edmond J. Safra Campus, The Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem, 9190402, Israel
| | - Bao-Sheng Qiu
- School of Life Sciences, Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei, 430079, China
| | - Nir Keren
- Department of Plant and Environmental Sciences, Edmond J. Safra Campus, The Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem, 9190402, Israel
| |
Collapse
|