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Masuda T, Bečková M, Turóczy Z, Pilný J, Sobotka R, Trinugroho JP, Nixon PJ, Prášil O, Komenda J. Accumulation of Cyanobacterial Photosystem II Containing the 'Rogue' D1 Subunit Is Controlled by FtsH Protease and Synthesis of the Standard D1 Protein. PLANT & CELL PHYSIOLOGY 2023; 64:660-673. [PMID: 36976618 DOI: 10.1093/pcp/pcad027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 06/16/2023]
Abstract
Unicellular diazotrophic cyanobacteria contribute significantly to the photosynthetic productivity of the ocean and the fixation of molecular nitrogen, with photosynthesis occurring during the day and nitrogen fixation during the night. In species like Crocosphaera watsonii WH8501, the decline in photosynthetic activity in the night is accompanied by the disassembly of oxygen-evolving photosystem II (PSII) complexes. Moreover, in the second half of the night phase, a small amount of rogue D1 (rD1), which is related to the standard form of the D1 subunit found in oxygen-evolving PSII, but of unknown function, accumulates but is quickly degraded at the start of the light phase. We show here that the removal of rD1 is independent of the rD1 transcript level, thylakoid redox state and trans-thylakoid pH but requires light and active protein synthesis. We also found that the maximal level of rD1 positively correlates with the maximal level of chlorophyll (Chl) biosynthesis precursors and enzymes, which suggests a possible role for rogue PSII (rPSII) in the activation of Chl biosynthesis just before or upon the onset of light, when new photosystems are synthesized. By studying strains of Synechocystis PCC 6803 expressing Crocosphaera rD1, we found that the accumulation of rD1 is controlled by the light-dependent synthesis of the standard D1 protein, which triggers the fast FtsH2-dependent degradation of rD1. Affinity purification of FLAG-tagged rD1 unequivocally demonstrated the incorporation of rD1 into a non-oxygen-evolving PSII complex, which we term rPSII. The complex lacks the extrinsic proteins stabilizing the oxygen-evolving Mn4CaO5 cluster but contains the Psb27 and Psb28-1 assembly factors.
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Affiliation(s)
- Takako Masuda
- Institute of Microbiology, The Czech Academy of Sciences, Centre Algatech, Opatovický mlýn, Třeboň 37901, Czech Republic
| | - Martina Bečková
- Institute of Microbiology, The Czech Academy of Sciences, Centre Algatech, Opatovický mlýn, Třeboň 37901, Czech Republic
| | - Zoltán Turóczy
- Institute of Microbiology, The Czech Academy of Sciences, Centre Algatech, Opatovický mlýn, Třeboň 37901, Czech Republic
| | - Jan Pilný
- Institute of Microbiology, The Czech Academy of Sciences, Centre Algatech, Opatovický mlýn, Třeboň 37901, Czech Republic
| | - Roman Sobotka
- Institute of Microbiology, The Czech Academy of Sciences, Centre Algatech, Opatovický mlýn, Třeboň 37901, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 1760, České Budějovice 370 05, Czech Republic
| | - Joko P Trinugroho
- Sir Ernst Chain Building-Wolfson Laboratories, Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Peter J Nixon
- Sir Ernst Chain Building-Wolfson Laboratories, Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Ondřej Prášil
- Institute of Microbiology, The Czech Academy of Sciences, Centre Algatech, Opatovický mlýn, Třeboň 37901, Czech Republic
| | - Josef Komenda
- Institute of Microbiology, The Czech Academy of Sciences, Centre Algatech, Opatovický mlýn, Třeboň 37901, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 1760, České Budějovice 370 05, Czech Republic
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Multiple Light-Dark Signals Regulate Expression of the DEAD-Box RNA Helicase CrhR in Synechocystis PCC 6803. Cells 2022; 11:cells11213397. [DOI: 10.3390/cells11213397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 10/18/2022] [Accepted: 10/20/2022] [Indexed: 11/16/2022] Open
Abstract
Since oxygenic photosynthesis evolved in the common ancestor of cyanobacteria during the Archean, a range of sensing and response strategies evolved to allow efficient acclimation to the fluctuating light conditions experienced in the diverse environments they inhabit. However, how these regulatory mechanisms are assimilated at the molecular level to coordinate individual gene expression is still being elucidated. Here, we demonstrate that integration of a series of three distinct light signals generate an unexpectedly complex network regulating expression of the sole DEAD-box RNA helicase, CrhR, encoded in Synechocystis sp. PCC 6803. The mechanisms function at the transcriptional, translational and post-translation levels, fine-tuning CrhR abundance to permit rapid acclimation to fluctuating light and temperature regimes. CrhR abundance is enhanced 15-fold by low temperature stress. We initially confirmed that the primary mechanism controlling crhR transcript accumulation at 20 °C requires a light quantity-driven reduction of the redox poise in the vicinity of the plastoquinone pool. Once transcribed, a specific light quality cue, a red light signal, was required for crhR translation, far-red reversal of which indicates a phytochrome-mediated mechanism. Examination of CrhR repression at 30 °C revealed that a redox- and light quality-independent light signal was required to initiate CrhR degradation. The crucial role of light was further revealed by the observation that dark conditions superseded the light signals required to initiate each of these regulatory processes. The findings reveal an unexpected complexity of light-dark sensing and signaling that regulate expression of an individual gene in cyanobacteria, an integrated mechanism of environmental perception not previously reported.
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Kılıç M, Gollan PJ, Lepistö A, Isojärvi J, Sakurai I, Aro E, Mulo P. Gene expression and organization of thylakoid protein complexes in the PSII-less mutant of Synechocystis sp. PCC 6803. PLANT DIRECT 2022; 6:e409. [PMID: 35774619 PMCID: PMC9219013 DOI: 10.1002/pld3.409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 05/13/2022] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
Photosystems I and II (PSI and PSII) are the integral components of the photosynthetic electron transport chain that utilize light to provide chemical energy for CO2 fixation. In this study, we investigated how the deficiency of PSII affects the gene expression, accumulation, and organization of thylakoid protein complexes as well as physiological characteristics of Synechocystis sp. PCC 6803 by combining biochemical, biophysical, and transcriptomic approaches. RNA-seq analysis showed upregulated expression of genes encoding the PSII core proteins, and downregulation of genes associated with interaction between light-harvesting phycobilisomes and PSI. Two-dimensional separation of thylakoid protein complexes confirmed the lack of PSII complexes, yet unassembled PSII subunits were detected. The content of PsaB representing PSI was lower, while the content of cytochrome b6f complexes was higher in the PSII-less strain as compared with control (CS). Application of oxygraph measurements revealed higher rates of dark respiration and lower PSI activity in the mutant. The latter likely resulted from the detected decrease in the accumulation of PSI, PSI monomerization, increased proportion of energetically decoupled phycobilisomes in PSII-less cultures, and low abundance of phycocyanin. Merging the functional consequences of PSII depletion with differential protein and transcript accumulation in the mutant, in comparison to CS, identified signal transduction from the photosynthetic apparatus to the genome level.
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Affiliation(s)
- Mehmet Kılıç
- Molecular Plant Biology, Department of Life TechnologiesUniversity of TurkuTurkuFinland
| | - Peter J. Gollan
- Molecular Plant Biology, Department of Life TechnologiesUniversity of TurkuTurkuFinland
| | - Anniina Lepistö
- Molecular Plant Biology, Department of Life TechnologiesUniversity of TurkuTurkuFinland
| | - Janne Isojärvi
- Molecular Plant Biology, Department of Life TechnologiesUniversity of TurkuTurkuFinland
- Present address:
Turku PET CentreUniversity of TurkuTurkuFinland
| | - Isamu Sakurai
- Molecular Plant Biology, Department of Life TechnologiesUniversity of TurkuTurkuFinland
| | - Eva‐Mari Aro
- Molecular Plant Biology, Department of Life TechnologiesUniversity of TurkuTurkuFinland
| | - Paula Mulo
- Molecular Plant Biology, Department of Life TechnologiesUniversity of TurkuTurkuFinland
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4
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Roles of Close Homologues SigB and SigD in Heat and High Light Acclimation of the Cyanobacterium Synechocystis sp. PCC 6803. Life (Basel) 2022; 12:life12020162. [PMID: 35207450 PMCID: PMC8875361 DOI: 10.3390/life12020162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/15/2022] [Accepted: 01/19/2022] [Indexed: 11/18/2022] Open
Abstract
Acclimation of cyanobacterium Synechocystis sp. PCC6803 to suboptimal conditions is largely dependent on adjustments of gene expression, which is highly controlled by the σ factor subunits of RNA polymerase (RNAP). The SigB and SigD σ factors are close homologues. Here we show that the sigB and sigD genes are both induced in high light and heat stresses. Comparison of transcriptomes of the control strain (CS), ΔsigB, ΔsigD, ΔsigBCE (containing SigD as the only functional group 2 σ factor), and ΔsigCDE (SigB as the only functional group 2 σ factor) strains in standard, high light, and high temperature conditions revealed that the SigB and SigD factors regulate different sets of genes and SigB and SigD regulons are highly dependent on stress conditions. The SigB regulon is bigger than the SigD regulon at high temperature, whereas, in high light, the SigD regulon is bigger than the SigB regulon. Furthermore, our results show that favoring the SigB or SigD factor by deleting other group 2 σ factors does not lead to superior acclimation to high light or high temperature, indicating that all group 2 σ factors play roles in the acclimation processes.
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5
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Linhartová M, Skotnicová P, Hakkila K, Tichý M, Komenda J, Knoppová J, Gilabert JF, Guallar V, Tyystjärvi T, Sobotka R. Mutations Suppressing the Lack of Prepilin Peptidase Provide Insights Into the Maturation of the Major Pilin Protein in Cyanobacteria. Front Microbiol 2021; 12:756912. [PMID: 34712217 PMCID: PMC8546353 DOI: 10.3389/fmicb.2021.756912] [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: 08/11/2021] [Accepted: 09/14/2021] [Indexed: 11/24/2022] Open
Abstract
Type IV pili are bacterial surface-exposed filaments that are built up by small monomers called pilin proteins. Pilins are synthesized as longer precursors (prepilins), the N-terminal signal peptide of which must be removed by the processing protease PilD. A mutant of the cyanobacterium Synechocystis sp. PCC 6803 lacking the PilD protease is not capable of photoautotrophic growth because of the impaired function of Sec translocons. Here, we isolated phototrophic suppressor strains of the original ΔpilD mutant and, by sequencing their genomes, identified secondary mutations in the SigF sigma factor, the γ subunit of RNA polymerase, the signal peptide of major pilin PilA1, and in the pilA1-pilA2 intergenic region. Characterization of suppressor strains suggests that, rather than the total prepilin level in the cell, the presence of non-glycosylated PilA1 prepilin is specifically harmful. We propose that the restricted lateral mobility of the non-glycosylated PilA1 prepilin causes its accumulation in the translocon-rich membrane domains, which attenuates the synthesis of membrane proteins.
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Affiliation(s)
- Markéta Linhartová
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia.,Faculty of Science, University of South Bohemia, České Budějovice, Czechia
| | - Petra Skotnicová
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Kaisa Hakkila
- Biotechnology/Molecular Plant Biology, University of Turku, Turku, Finland
| | - Martin Tichý
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Josef Komenda
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Jana Knoppová
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | | | - Victor Guallar
- Barcelona Supercomputing Center, Barcelona, Spain.,ICREA: Institucio Catalana de Recerca i Estudis Avançats Passeig Lluis Companys, Barcelona, Spain
| | - Taina Tyystjärvi
- Biotechnology/Molecular Plant Biology, University of Turku, Turku, Finland
| | - Roman Sobotka
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
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Migur A, Heyl F, Fuss J, Srikumar A, Huettel B, Steglich C, Prakash JSS, Reinhardt R, Backofen R, Owttrim GW, Hess WR. The temperature-regulated DEAD-box RNA helicase CrhR interactome: Autoregulation and photosynthesis-related transcripts. JOURNAL OF EXPERIMENTAL BOTANY 2021:erab416. [PMID: 34499142 DOI: 10.1093/jxb/erab416] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Indexed: 06/13/2023]
Abstract
RNA helicases play crucial functions in RNA biology. In plants, RNA helicases are encoded by large gene families, performing roles in abiotic stress responses, development, the post-transcriptional regulation of gene expression as well as house-keeping functions. Several of these RNA helicases are targeted to the organelles, mitochondria and chloroplasts. Cyanobacteria are the direct evolutionary ancestors of plant chloroplasts. The cyanobacterium Synechocystis 6803 encodes a single DEAD-box RNA helicase, CrhR, that is induced by a range of abiotic stresses, including low temperature. Though the ΔcrhR mutant exhibits a severe cold-sensitive phenotype, the physiological function(s) performed by CrhR have not been described. To identify transcripts interacting with CrhR, we performed RNA co-immunoprecipitation with extracts from a Synechocystis crhR deletion mutant expressing the FLAG-tagged native CrhR or a K57A mutated version with an anticipated enhanced RNA binding. The composition of the interactome was strikingly biased towards photosynthesis-associated and redox-controlled transcripts. A transcript highly enriched in all experiments was the crhR mRNA, suggesting an auto-regulatory molecular mechanism. The identified interactome explains the described physiological role of CrhR in response to the redox poise of the photosynthetic electron transport chain and characterizes CrhR as an enzyme with a diverse range of transcripts as molecular targets.
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Affiliation(s)
- Anzhela Migur
- Faculty of Biology, University of Freiburg, Schänzlestr., Freiburg, Germany
| | - Florian Heyl
- Department of Computer Science, University of Freiburg, Georges-Koehler-Allee, Freiburg, Germany
| | - Janina Fuss
- Max Planck-Genome-Centre Cologne, Carl-von-Linné-Weg, Köln, Germany
| | - Afshan Srikumar
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Bruno Huettel
- Max Planck-Genome-Centre Cologne, Carl-von-Linné-Weg, Köln, Germany
| | - Claudia Steglich
- Faculty of Biology, University of Freiburg, Schänzlestr., Freiburg, Germany
| | - Jogadhenu S S Prakash
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | | | - Rolf Backofen
- Department of Computer Science, University of Freiburg, Georges-Koehler-Allee, Freiburg, Germany
| | - George W Owttrim
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Wolfgang R Hess
- Faculty of Biology, University of Freiburg, Schänzlestr., Freiburg, Germany
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Bashir F, Rehman AU, Szabó M, Vass I. Singlet oxygen damages the function of Photosystem II in isolated thylakoids and in the green alga Chlorella sorokiniana. PHOTOSYNTHESIS RESEARCH 2021; 149:93-105. [PMID: 34009505 PMCID: PMC8382655 DOI: 10.1007/s11120-021-00841-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
Singlet oxygen (1O2) is an important damaging agent, which is produced during illumination by the interaction of the triplet excited state pigment molecules with molecular oxygen. In cells of photosynthetic organisms 1O2 is formed primarily in chlorophyll containing complexes, and damages pigments, lipids, proteins and other cellular constituents in their environment. A useful approach to study the physiological role of 1O2 is the utilization of external photosensitizers. In the present study, we employed a multiwell plate-based screening method in combination with chlorophyll fluorescence imaging to characterize the effect of externally produced 1O2 on the photosynthetic activity of isolated thylakoid membranes and intact Chlorella sorokiniana cells. The results show that the external 1O2 produced by the photosensitization reactions of Rose Bengal damages Photosystem II both in isolated thylakoid membranes and in intact cells in a concentration dependent manner indicating that 1O2 plays a significant role in photodamage of Photosystem II.
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Affiliation(s)
- Faiza Bashir
- Biological Research Centre, Institute of Plant Biology, Eötvös Loránd Research Network (ELKH), Szeged, Hungary
- Doctoral School of Biology, University of Szeged, Szeged, Hungary
| | - Ateeq Ur Rehman
- Biological Research Centre, Institute of Plant Biology, Eötvös Loránd Research Network (ELKH), Szeged, Hungary
| | - Milán Szabó
- Biological Research Centre, Institute of Plant Biology, Eötvös Loránd Research Network (ELKH), Szeged, Hungary
- Climate Change Cluster, University of Technology Sydney, Sydney, Australia
| | - Imre Vass
- Biological Research Centre, Institute of Plant Biology, Eötvös Loránd Research Network (ELKH), Szeged, Hungary.
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8
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Forsman JA, Eaton-Rye JJ. The hydrophobicity of mutations targeting D1:Val219 modifies formate and diuron binding in the quinone-Fe-acceptor complex of Photosystem II. PHYSIOLOGIA PLANTARUM 2021; 172:2217-2225. [PMID: 34050526 DOI: 10.1111/ppl.13469] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/10/2021] [Accepted: 05/26/2021] [Indexed: 06/12/2023]
Abstract
The D1:Val219 residue of Photosystem II in the cyanobacterium Synechocystis sp. PCC 6803 was mutated to alanine or isoleucine, creating the V219A and V219I mutants, respectively. Oxygen evolution was slowed in these mutants, while chlorophyll a fluorescence induction assays indicated slowed electron transfer. As previously observed [Erickson J.M., Rahire, M., Rochaix, J.-D. and Mets. L. (1985) Science, 228, 204-207], the V219I mutant was resistant to 3,4-dichloro-1,1-dimethyl urea (DCMU); however, the V219A strain displayed no DCMU resistance. Additionally, the V219A strain was less sensitive to the addition of formate than the control, while the V219I strain was more sensitive to formate. Both mutant strains were susceptible to photodamage and required protein synthesis for recovery. We hypothesize that the sensitivity to DCMU and the extent of bicarbonate-reversible formate-induced inhibition, as well as the capacity for recovery in cells following photodamage, are influenced by the hydrophobicity of the environment associated with the Val219 residue in D1.
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Affiliation(s)
- Jack A Forsman
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
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9
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Kang MJ, Hong SJ, Yoo D, Cho BK, Lee H, Choi HK, Kim DM, Lee CG. Photosynthetic production of biodiesel in Synechocystis sp. PCC6803 transformed with insect or plant fatty acid methyltransferase. Bioprocess Biosyst Eng 2021; 44:1433-1439. [PMID: 33656615 DOI: 10.1007/s00449-021-02520-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 01/25/2021] [Indexed: 01/10/2023]
Abstract
Biodiesel contains methyl or ethyl esters of long-chain fatty acids and has recently attracted increasing attention. Microalgae have emerged as a sustainable biodiesel production system owing to their photosynthetic potential. However, the conversion of microalgal biomass to biodiesel requires high energy and is costly. This study aimed to overcome the high cost of the pretreatment process by generating cyanobacteria converting fatty acids to fatty acids methyl ester (FAME) in vivo by introducing the fatty acid methyl ester transferase (FAMT) gene. Two FAMT genes from Drosophila melanogaster and Arabidopsis thaliana were selected and their codons were optimized for insertion in the Synechocystis sp. PCC6803 genome through homologous recombination, respectively. FAMT mRNA and protein expression levels were confirmed through reverse-transcription PCR and western blot analysis, respectively. Furthermore, heterologous expression of the FAMT genes yielded FAME, which was analyzed by gas chromatography. We found that FAMT transformants can be further metabolically optimized and applied for commercial production of biodiesel.
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Affiliation(s)
- Mi-Jin Kang
- Department of Biological Engineering, Inha University, Incheon, 22212, Republic of Korea
| | - Seong-Joo Hong
- Department of Biological Engineering, Inha University, Incheon, 22212, Republic of Korea
| | - Danbi Yoo
- Department of Biological Engineering, Inha University, Incheon, 22212, Republic of Korea
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 34051, Republic of Korea
| | - Hookeun Lee
- College of Pharmacy, Gachon University, Incheon, 21936, Republic of Korea
| | - Hyung-Kyoon Choi
- College of Pharmacy, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Dong-Myung Kim
- Department of Fine Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Choul-Gyun Lee
- Department of Biological Engineering, Inha University, Incheon, 22212, Republic of Korea.
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10
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Kodru S, Ur Rehman A, Vass I. Chloramphenicol enhances Photosystem II photodamage in intact cells of the cyanobacterium Synechocystis PCC 6803. PHOTOSYNTHESIS RESEARCH 2020; 145:227-235. [PMID: 32979144 PMCID: PMC7541379 DOI: 10.1007/s11120-020-00784-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 09/09/2020] [Indexed: 06/11/2023]
Abstract
The effect of chloramphenicol, an often used protein synthesis inhibitor, in photosynthetic systems was studied on the rate of Photosystem II (PSII) photodamage in the cyanobacterium Synechocystis PCC 6803. Light-induced loss of PSII activity was compared in the presence of chloramphenicol and another protein synthesis inhibitor, lincomycin, by measuring the rate of oxygen evolution in Synechocystis 6803 cells. Our data show that the rate of PSII photodamage was significantly enhanced by chloramphenicol, at the usually applied 200 μg mL-1 concentration, relative to that obtained in the presence of lincomycin. Chloramphenicol-induced enhancement of photodamage has been observed earlier in isolated PSII membrane particles, and has been assigned to the damaging effect of chloramphenicol-mediated superoxide production (Rehman et al. 2016, Front Plant Sci 7:479). This effect points to the involvement of superoxide as damaging agent in the presence of chloramphenicol also in Synechocystis cells. The chloramphenicol-induced enhancement of photodamage was observed not only in wild-type Synechocystis 6803, which contains both Photosystem I (PSI) and PSII, but also in a PSI-less mutant which contains only PSII. Importantly, the rate of PSII photodamage was also enhanced by the absence of PSI when compared to that in the wild-type strain under all conditions studied here, i.e., without addition and in the presence of protein synthesis inhibitors. We conclude that chloramphenicol enhances photodamage mostly by its interaction with PSII, leading probably to superoxide production. The presence of PSI is also an important regulatory factor of PSII photodamage most likely via decreasing excitation pressure on PSII.
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Affiliation(s)
- Sandeesha Kodru
- Institute of Plant Biology, Biological Research Centre, Temesvari krt. 62, Szeged, 6726, Hungary
- Doctoral School of Biology, University of Szeged, Szeged, Hungary
| | - Ateeq Ur Rehman
- Institute of Plant Biology, Biological Research Centre, Temesvari krt. 62, Szeged, 6726, Hungary
| | - Imre Vass
- Institute of Plant Biology, Biological Research Centre, Temesvari krt. 62, Szeged, 6726, Hungary.
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11
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Mahbub M, Hemm L, Yang Y, Kaur R, Carmen H, Engl C, Huokko T, Riediger M, Watanabe S, Liu LN, Wilde A, Hess WR, Mullineaux CW. mRNA localization, reaction centre biogenesis and thylakoid membrane targeting in cyanobacteria. NATURE PLANTS 2020; 6:1179-1191. [PMID: 32895528 DOI: 10.1038/s41477-020-00764-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
The thylakoid membranes of cyanobacteria form a complex intracellular membrane system with a distinctive proteome. The sites of biogenesis of thylakoid proteins remain uncertain, as do the signals that direct thylakoid membrane-integral proteins to the thylakoids rather than to the plasma membrane. Here, we address these questions by using fluorescence in situ hybridization to probe the subcellular location of messenger RNA molecules encoding core subunits of the photosystems in two cyanobacterial species. These mRNAs cluster at thylakoid surfaces mainly adjacent to the central cytoplasm and the nucleoid, in contrast to mRNAs encoding proteins with other locations. Ribosome association influences the distribution of the photosynthetic mRNAs on the thylakoid surface, but thylakoid affinity is retained in the absence of ribosome association. However, thylakoid association is disrupted in a mutant lacking two mRNA-binding proteins, which probably play roles in targeting photosynthetic proteins to the thylakoid membrane.
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Affiliation(s)
- Moontaha Mahbub
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
- Department of Botany, Jagannath University, Dhaka, Bangladesh
| | - Luisa Hemm
- Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Yuxiao Yang
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Ramanpreet Kaur
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Helder Carmen
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Christoph Engl
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Tuomas Huokko
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | | | - Satoru Watanabe
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Lu-Ning Liu
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
- College of Marine Life Sciences, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China
| | - Annegret Wilde
- Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Wolfgang R Hess
- Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Conrad W Mullineaux
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK.
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12
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Fagerlund RD, Forsman JA, Biswas S, Vass I, Davies FK, Summerfield TC, Eaton-Rye JJ. Stabilization of Photosystem II by the PsbT protein impacts photodamage, repair and biogenesis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148234. [PMID: 32485158 DOI: 10.1016/j.bbabio.2020.148234] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 05/02/2020] [Accepted: 05/25/2020] [Indexed: 10/24/2022]
Abstract
Photosystem II (PS II) catalyzes the light-driven process of water splitting in oxygenic photosynthesis. Four core membrane-spanning proteins, including D1 that binds the majority of the redox-active co-factors, are surrounded by 13 low-molecular-weight (LMW) proteins. We previously observed that deletion of the LMW PsbT protein in the cyanobacterium Synechocystis sp. PCC 6803 slowed electron transfer between the primary and secondary plastoquinone electron acceptors QA and QB and increased the susceptibility of PS II to photodamage. Here we show that photodamaged ∆PsbT cells exhibit unimpaired rates of oxygen evolution if electron transport is supported by HCO3- even though the cells exhibit negligible variable fluorescence. We find that the protein environment in the vicinity of QA and QB is altered upon removal of PsbT resulting in inhibition of QA- oxidation in the presence of 2,5-dimethyl-1,4-benzoquinone, an artificial PS II-specific electron acceptor. Thermoluminescence measurements revealed an increase in charge recombination between the S2 oxidation state of the water-oxidizing complex and QA- by the indirect radiative pathway in ∆PsbT cells and this is accompanied by increased 1O2 production. At the protein level, both D1 removal and replacement, as well as PS II biogenesis, were accelerated in the ∆PsbT strain. Our results demonstrate that PsbT plays a key role in optimizing the electron acceptor complex of the acceptor side of PS II and support the view that repair and biogenesis of PS II share an assembly pathway that incorporates both de novo synthesis and recycling of the assembly modules associated with the core membrane-spanning proteins.
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Affiliation(s)
- Robert D Fagerlund
- Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand
| | - Jack A Forsman
- Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand
| | - Sandeep Biswas
- Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand
| | - Imre Vass
- Institute of Plant Biology, Biological Research Center, Szeged, Hungary
| | - Fiona K Davies
- Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand
| | | | - Julian J Eaton-Rye
- Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand.
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Lysine Propionylation is a Widespread Post-Translational Modification Involved in Regulation of Photosynthesis and Metabolism in Cyanobacteria. Int J Mol Sci 2019; 20:ijms20194792. [PMID: 31561603 PMCID: PMC6801645 DOI: 10.3390/ijms20194792] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 12/31/2022] Open
Abstract
Lysine propionylation is a reversible and widely distributed post-translational modification that is known to play a regulatory role in both eukaryotes and prokaryotes. However, the extent and function of lysine propionylation in photosynthetic organisms remains unclear. Cyanobacteria are the most ancient group of Gram-negative bacteria capable of oxygenic photosynthesis, and are of great importance to global carbon and nitrogen cycles. Here, we carried out a systematic study of lysine propionylaiton in cyanobacteria where we used Synechocystis sp. PCC 6803 (Synechocystis) as a model. Combining high-affinity anti-propionyllysine pan antibodies with high-accuracy mass spectrometry (MS) analysis, we identified 111 unique lysine propionylation sites on 69 proteins in Synechocystis. Further bioinformatic analysis showed that a large fraction of the propionylated proteins were involved in photosynthesis and metabolism. The functional significance of lysine propionylation on the enzymatic activity of fructose-1,6-bisphosphatase (FbpI) was studied by site-directed mutagenesis and biochemical studies. Further functional studies revealed that the propionylation level of subunit II of photosystem I (PsaD) was obviously increased after high light (HL) treatment, suggesting that propionylation may be involved in high light adaption in Synechocystis. Thus, our findings provide novel insights into the range of functions regulated by propionylation and reveal that reversible propionylation is a functional modification with the potential to regulate photosynthesis and carbon metabolism in Synechocystis, as well as in other photosynthetic organisms.
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Santana-Sanchez A, Solymosi D, Mustila H, Bersanini L, Aro EM, Allahverdiyeva Y. Flavodiiron proteins 1-to-4 function in versatile combinations in O 2 photoreduction in cyanobacteria. eLife 2019; 8:e45766. [PMID: 31294693 PMCID: PMC6658166 DOI: 10.7554/elife.45766] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 07/10/2019] [Indexed: 12/15/2022] Open
Abstract
Flavodiiron proteins (FDPs) constitute a group of modular enzymes widespread in Bacteria, Archaea and Eukarya. Synechocystis sp. PCC 6803 has four FDPs (Flv1-4), which are essential for the photoprotection of photosynthesis. A direct comparison of light-induced O2 reduction (Mehler-like reaction) under high (3% CO2, HC) and low (air level CO2, LC) inorganic carbon conditions demonstrated that the Flv1/Flv3 heterodimer is solely responsible for an efficient steady-state O2 photoreduction under HC, with flv2 and flv4 expression strongly down-regulated. Conversely, under LC conditions, Flv1/Flv3 acts only as a transient electron sink, due to the competing withdrawal of electrons by the highly induced NDH-1 complex. Further, in vivo evidence is provided indicating that Flv2/Flv4 contributes to the Mehler-like reaction when naturally expressed under LC conditions, or, when artificially overexpressed under HC. The O2 photoreduction driven by Flv2/Flv4 occurs down-stream of PSI in a coordinated manner with Flv1/Flv3 and supports slow and steady-state O2 photoreduction.
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Affiliation(s)
| | - Daniel Solymosi
- Molecular Plant Biology, Department of BiochemistryUniversity of TurkuTurkuFinland
| | - Henna Mustila
- Molecular Plant Biology, Department of BiochemistryUniversity of TurkuTurkuFinland
| | - Luca Bersanini
- Molecular Plant Biology, Department of BiochemistryUniversity of TurkuTurkuFinland
| | - Eva-Mari Aro
- Molecular Plant Biology, Department of BiochemistryUniversity of TurkuTurkuFinland
| | - Yagut Allahverdiyeva
- Molecular Plant Biology, Department of BiochemistryUniversity of TurkuTurkuFinland
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15
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Xu HF, Dai GZ, Qiu BS. Weak red light plays an important role in awakening the photosynthetic machinery following desiccation in the subaerial cyanobacterium Nostoc flagelliforme. Environ Microbiol 2019; 21:2261-2272. [PMID: 30895692 DOI: 10.1111/1462-2920.14600] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 01/31/2019] [Accepted: 03/19/2019] [Indexed: 11/28/2022]
Abstract
The subaerial cyanobacterium Nostoc flagelliforme can survive for years in the desiccated state and light exposure may stimulate photosynthetic recovery during rehydration. However, the influence of light quality on photosynthetic recovery and the underlying mechanism remain unresolved. Exposure of field collected N. flagelliforme to light intensity ≥2 μmol photons m-2 s-1 showed that the speed of photosystem II (PSII) recovery was in the following order: red > green > blue ≈ violet light. Decreasing the light intensity showed that weak red light stimulated PSII recovery during rehydration. The chlorophyll fluorescence transient and oxygen evolution activity indicated that the oxygen evolution complex (OEC) was the activated site triggered by weak red light. The damaged D1 protein accumulated in the thylakoid membrane during dehydration and is degraded and resynthesized during dark rehydration. PsbO interaction with the thylakoid membrane was induced by weak red light. Thus, weak red light plays an important role in triggering OEC photoactivation and the formation of functional PSII during rehydration. In its arid habitats, weak red light could stimulate the awakening of dormant N. flagelliforme after absorbing water from nighttime dew or rain to maximize growth during the early daylight hours of the dry season.
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Affiliation(s)
- Hai-Feng Xu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, 430079, P. R. China
| | - Guo-Zheng Dai
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, 430079, P. R. China
| | - Bao-Sheng Qiu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, 430079, P. R. China
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16
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Cordara A, Manfredi M, van Alphen P, Marengo E, Pirone R, Saracco G, Branco Dos Santos F, Hellingwerf KJ, Pagliano C. Response of the thylakoid proteome of Synechocystis sp. PCC 6803 to photohinibitory intensities of orange-red light. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 132:524-534. [PMID: 30316162 DOI: 10.1016/j.plaphy.2018.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 10/01/2018] [Accepted: 10/01/2018] [Indexed: 06/08/2023]
Abstract
Photoautotrophic growth of Synechocystis sp. PCC 6803 in a flat-panel photobioreactor, run in turbidostat mode under increasing intensities of orange-red light (636 nm), showed a maximal growth rate (0.12 h-1) at 300 μmolphotons m-2 s-1, whereas first signs of photoinhibition were detected above 800 μmolphotons m-2 s-1. To investigate the dynamic modulation of the thylakoid proteome in response to photoinhibitory light intensities, quantitative proteomics analyses by SWATH mass spectrometry were performed by comparing thylakoid membranes extracted from Synechocystis grown under low-intensity illumination (i.e. 50 μmolphotons m-2 s-1) with samples isolated from cells subjected to photoinhibitory light regimes (800, 950 and 1460 μmolphotons m-2 s-1). We identified and quantified 126 proteins with altered abundance in all three photoinhibitory illumination regimes. These data reveal the strategies by which Synechocystis responds to photoinibitory growth irradiances of orange-red light. The accumulation of core proteins of Photosystem II and reduction of oxygen-evolving-complex subunits in photoinhibited cells revealed a different turnover and repair rates of the integral and extrinsic Photosystem II subunits with variation of light intensity. Furthermore, Synechocystis displayed a differentiated response to photoinhibitory regimes also regarding Photosystem I: the amount of PsaD, PsaE, PsaJ and PsaM subunits decreased, while there was an increased abundance of the PsaA, PsaB, Psak2 and PsaL proteins. Photoinhibition with 636 nm light also elicited an increased capacity for cyclic electron transport, a lowering of the amount of phycobilisomes and an increase of the orange carotenoid protein content, all presumably as a photoprotective mechanism against the generation of reactive oxygen species.
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Affiliation(s)
- Alessandro Cordara
- Applied Science and Technology Department-BioSolar Lab, Politecnico di Torino, Environment Park, Via Livorno 60, 10144, Torino, Italy; Centre for Sustainable Future Technologies, Istituto Italiano di Tecnologia, Environment Park, Via Livorno 60, 10144, Torino, Italy
| | - Marcello Manfredi
- ISALIT-Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy; Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy
| | - Pascal van Alphen
- Molecular Microbial Physiology Group, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1090, GE, Amsterdam, Netherlands
| | - Emilio Marengo
- ISALIT-Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy; Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy
| | - Raffaele Pirone
- Applied Science and Technology Department, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy
| | - Guido Saracco
- Applied Science and Technology Department, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy
| | - Filipe Branco Dos Santos
- Molecular Microbial Physiology Group, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1090, GE, Amsterdam, Netherlands
| | - Klaas J Hellingwerf
- Molecular Microbial Physiology Group, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1090, GE, Amsterdam, Netherlands
| | - Cristina Pagliano
- Applied Science and Technology Department-BioSolar Lab, Politecnico di Torino, Environment Park, Via Livorno 60, 10144, Torino, Italy.
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Abstract
Ribosome profiling accesses the translational step of gene expression via deep sequencing of ribosome-protected mRNA footprints. Pairing of ribosome profiling and transcriptomics data provides a translational efficiency for each gene. Here, the translatome and transcriptome of the model cyanobacterium
Synechocystis
were compared under carbon-replete and carbon starvation conditions. The latter may be experienced when cyanobacteria are cultivated in poorly mixed bioreactors or engineered to be product-secreting cell factories. A small fraction of genes (<200), including stress response genes, showed changes in translational efficiency during carbon starvation, indicating condition-dependent translation-level regulation. We observed ribosome occupancy in untranslated regions, possibly due to an alternative translation initiation mechanism in
Synechocystis.
The higher proportion of ribosomes residing in untranslated regions during carbon starvation may be a mechanism to quickly inactivate superfluous ribosomes. This work provides the first ribosome profiling data for cyanobacteria and reveals new regulation strategies for coping with nutrient limitation.
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18
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Dogra V, Rochaix JD, Kim C. Singlet oxygen-triggered chloroplast-to-nucleus retrograde signalling pathways: An emerging perspective. PLANT, CELL & ENVIRONMENT 2018; 41:1727-1738. [PMID: 29749057 DOI: 10.1111/pce.13332] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/27/2018] [Accepted: 04/27/2018] [Indexed: 05/19/2023]
Abstract
Singlet oxygen (1 O2 ) is a prime cause of photo-damage of the photosynthetic apparatus. The chlorophyll molecules in the photosystem II reaction center and in the light-harvesting antenna complex are major sources of 1 O2 generation. It has been thought that the generation of 1 O2 mainly takes place in the appressed regions of the thylakoid membranes, namely, the grana core, where most of the active photosystem II complexes are localized. Apart from being a toxic molecule, new evidence suggests that 1 O2 significantly contributes to chloroplast-to-nucleus retrograde signalling that primes acclimation and cell death responses. Interestingly, recent studies reveal that chloroplasts operate two distinct 1 O2 -triggered retrograde signalling pathways in which β-carotene and a nuclear-encoded chloroplast protein EXECUTER1 play essential roles as signalling mediators. The coexistence of these mediators raises several questions: their crosstalk, source(s) of 1 O2 , downstream signalling components, and the perception and reaction mechanism of these mediators towards 1 O2 . In this review, we mainly discuss the molecular genetic basis of the mode of action of these two putative 1 O2 sensors and their corresponding retrograde signalling pathways. In addition, we also propose the possible existence of an alternative source of 1 O2 , which is spatially and functionally separated from the grana core.
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Affiliation(s)
- Vivek Dogra
- Shanghai Center for Plant Stress Biology and Center of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Jean-David Rochaix
- Department of Molecular Biology and Plant Biology, University of Geneva, 1205, Geneva, Switzerland
| | - Chanhong Kim
- Shanghai Center for Plant Stress Biology and Center of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
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19
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Koskinen S, Hakkila K, Kurkela J, Tyystjärvi E, Tyystjärvi T. Inactivation of group 2 σ factors upregulates production of transcription and translation machineries in the cyanobacterium Synechocystis sp. PCC 6803. Sci Rep 2018; 8:10305. [PMID: 29985458 PMCID: PMC6037674 DOI: 10.1038/s41598-018-28736-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 06/26/2018] [Indexed: 11/17/2022] Open
Abstract
We show that the formation of the RNAP holoenzyme with the primary σ factor SigA increases in the ΔsigBCDE strain of the cyanobacterium Synechocystis sp. PCC 6803 lacking all group 2 σ factors. The high RNAP-SigA holoenzyme content directly induces transcription of a particular set of housekeeping genes, including ones encoding transcription and translation machineries. In accordance with upregulated transcripts, ΔsigBCDE contain more RNAPs and ribosomal subunits than the control strain. Extra RNAPs are fully active, and the RNA content of ΔsigBCDE cells is almost tripled compared to that in the control strain. Although ΔsigBCDE cells produce extra rRNAs and ribosomal proteins, functional extra ribosomes are not formed, and translation activity and protein content remained similar in ΔsigBCDE as in the control strain. The arrangement of the RNA polymerase core genes together with the ribosomal protein genes might play a role in the co-regulation of transcription and translation machineries. Sequence logos were constructed to compare promoters of those housekeeping genes that directly react to the RNAP-SigA holoenzyme content and those ones that do not. Cyanobacterial strains with engineered transcription and translation machineries might provide solutions for construction of highly efficient production platforms for biotechnical applications in the future.
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Affiliation(s)
- Satu Koskinen
- Department of Biochemistry, University of Turku, FI-20014, Turku, Finland
| | - Kaisa Hakkila
- Department of Biochemistry, University of Turku, FI-20014, Turku, Finland
| | - Juha Kurkela
- Department of Biochemistry, University of Turku, FI-20014, Turku, Finland
| | - Esa Tyystjärvi
- Department of Biochemistry, University of Turku, FI-20014, Turku, Finland
| | - Taina Tyystjärvi
- Department of Biochemistry, University of Turku, FI-20014, Turku, Finland.
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20
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Vuorijoki L, Tiwari A, Kallio P, Aro EM. Inactivation of iron-sulfur cluster biogenesis regulator SufR in Synechocystis sp. PCC 6803 induces unique iron-dependent protein-level responses. Biochim Biophys Acta Gen Subj 2017; 1861:1085-1098. [PMID: 28216046 DOI: 10.1016/j.bbagen.2017.02.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 01/31/2017] [Accepted: 02/14/2017] [Indexed: 10/20/2022]
Abstract
BACKGROUND Iron-sulfur (Fe-S) clusters are protein-bound cofactors associated with cellular electron transport and redox sensing, with multiple specific functions in oxygen-evolving photosynthetic cyanobacteria. The aim here was to elucidate protein-level effects of the transcriptional repressor SufR involved in the regulation of Fe-S cluster biogenesis in the cyanobacterium Synechocystis sp. PCC 6803. METHODS The approach was to quantitate 94 pre-selected target proteins associated with various metabolic functions using SRM in Synechocystis. The evaluation was conducted in response to sufR deletion under different iron conditions, and complemented with EPR analysis on the functionality of the photosystems I and II as well as with RT-qPCR to verify the effects of SufR also on transcript level. RESULTS The results on both protein and transcript levels show that SufR acts not only as a repressor of the suf operon when iron is available but also has other direct and indirect functions in the cell, including maintenance of the expression of pyruvate:ferredoxin oxidoreductase NifJ and other Fe-S cluster proteins under iron sufficient conditions. Furthermore, the results imply that in the absence of iron the suf operon is repressed by some additional regulatory mechanism independent of SufR. CONCLUSIONS The study demonstrates that Fe-S cluster metabolism in Synechocystis is stringently regulated, and has complex interactions with multiple primary functions in the cell, including photosynthesis and central carbon metabolism. GENERAL SIGNIFICANCE The study provides new insight into the regulation of Fe-S cluster biogenesis via suf operon, and the associated wide-ranging protein-level changes in photosynthetic cyanobacteria.
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Affiliation(s)
- Linda Vuorijoki
- Molecular Plant Biology, Department of Biochemistry, University of Turku, FI-20014 Turku, Finland.
| | - Arjun Tiwari
- Molecular Plant Biology, Department of Biochemistry, University of Turku, FI-20014 Turku, Finland.
| | - Pauli Kallio
- Molecular Plant Biology, Department of Biochemistry, University of Turku, FI-20014 Turku, Finland.
| | - Eva-Mari Aro
- Molecular Plant Biology, Department of Biochemistry, University of Turku, FI-20014 Turku, Finland.
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21
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Albers SC, Peebles CAM. Evaluating Light-Induced Promoters for the Control of Heterologous Gene Expression inSynechocystis sp. PCC 6803. Biotechnol Prog 2016; 33:45-53. [DOI: 10.1002/btpr.2396] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 10/07/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Stevan C. Albers
- Cell and Molecular Biology Graduate Program; Colorado State University; Fort Collins CO 80523
| | - Christie A. M. Peebles
- Cell and Molecular Biology Graduate Program; Colorado State University; Fort Collins CO 80523
- Dept. of Chemical and Biological Engineering; Colorado State University; Fort Collins CO 80523
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22
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Cyanobacterial RNA Helicase CrhR Localizes to the Thylakoid Membrane Region and Cosediments with Degradosome and Polysome Complexes in Synechocystis sp. Strain PCC 6803. J Bacteriol 2016; 198:2089-99. [PMID: 27215789 DOI: 10.1128/jb.00267-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 05/20/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The cyanobacterium Synechocystis sp. strain PCC 6803 encodes a single DEAD box RNA helicase, CrhR, whose expression is tightly autoregulated in response to cold stress. Subcellular localization and proteomic analysis results indicate that CrhR localizes to both the cytoplasmic and thylakoid membrane regions and cosediments with polysome and RNA degradosome components. Evidence is presented that either functional RNA helicase activity or a C-terminal localization signal was required for polysome but not thylakoid membrane localization. Polysome fractionation and runoff translation analysis results indicate that CrhR associates with actively translating polysomes. The data implicate a role for CrhR in translation or RNA degradation in the thylakoid region related to thylakoid biogenesis or stability, a role that is enhanced at low temperature. Furthermore, CrhR cosedimentation with polysome and RNA degradosome complexes links alteration of RNA secondary structure with a potential translation-RNA degradation complex in Synechocystis IMPORTANCE The interaction between mRNA translation and degradation is a major determinant controlling gene expression. Regulation of RNA function by alteration of secondary structure by RNA helicases performs crucial roles, not only in both of these processes but also in all aspects of RNA metabolism. Here, we provide evidence that the cyanobacterial RNA helicase CrhR localizes to both the cytoplasmic and thylakoid membrane regions and cosediments with actively translating polysomes and RNA degradosome components. These findings link RNA helicase alteration of RNA secondary structure with translation and RNA degradation in prokaryotic systems and contribute to the data supporting the idea of the existence of a macromolecular machine catalyzing these reactions in prokaryotic systems, an association hitherto recognized only in archaea and eukarya.
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23
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Varkey D, Mazard S, Ostrowski M, Tetu SG, Haynes P, Paulsen IT. Effects of low temperature on tropical and temperate isolates of marine Synechococcus. THE ISME JOURNAL 2016; 10:1252-63. [PMID: 26495993 PMCID: PMC5029218 DOI: 10.1038/ismej.2015.179] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Revised: 08/01/2015] [Accepted: 08/24/2015] [Indexed: 11/08/2022]
Abstract
Temperature is an important factor influencing the distribution of marine picocyanobacteria. However, molecular responses contributing to temperature preferences are poorly understood in these important primary producers. We compared the temperature acclimation of a tropical Synechococcus strain WH8102 with temperate strain BL107 at 18 °C relative to 22 °C and examined their global protein expression, growth patterns, photosynthetic efficiency and lipid composition. Global protein expression profiles demonstrate the partitioning of the proteome into major categories: photosynthesis (>40%), translation (10-15%) and membrane transport (2-8%) with distinct differences between and within strains grown at different temperatures. At low temperature, growth and photosynthesis of strain WH8102 was significantly decreased, while BL107 was largely unaffected. There was an increased abundance of proteins involved in protein biosynthesis at 18 °C for BL107. Each strain showed distinct differences in lipid composition with higher unsaturation in strain BL107. We hypothesize that differences in membrane fluidity, abundance of protein biosynthesis machinery and the maintenance of photosynthesis efficiency contribute to the acclimation of strain BL107 to low temperature. Additional proteins unique to BL107 may also contribute to this strain's improved fitness at low temperature. Such adaptive capacities are likely important factors favoring growth of temperate strains over tropical strains in high latitude niches.
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Affiliation(s)
- Deepa Varkey
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Sophie Mazard
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Martin Ostrowski
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Sasha G Tetu
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Paul Haynes
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Ian T Paulsen
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia
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24
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Nesbit AD, Whippo C, Hangarter RP, Kehoe DM. Translation initiation factor 3 families: what are their roles in regulating cyanobacterial and chloroplast gene expression? PHOTOSYNTHESIS RESEARCH 2015; 126:147-59. [PMID: 25630975 DOI: 10.1007/s11120-015-0074-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 01/02/2015] [Indexed: 05/09/2023]
Abstract
Initiation is a key control point for the regulation of translation in prokaryotes and prokaryotic-like translation systems such as those in plant chloroplasts. Genome sequencing and biochemical studies are increasingly demonstrating differences in many aspects of translation between well-studied microbes such as Escherichia coli and lesser studied groups such as cyanobacteria. Analyses of chloroplast translation have revealed its prokaryotic origin but also uncovered many unique aspects that do not exist in E. coli. Recently, a novel form of posttranscriptional regulation by light color was discovered in the filamentous cyanobacterium Fremyella diplosiphon that requires a putative stem-loop and involves the use of two different prokaryotic translation initiation factor 3s (IF3s). Multiple (up to five) putative IF3s have now been found to be encoded in 22 % of sequenced cyanobacterial genomes and 26 % of plant nuclear genomes. The lack of similar light-color regulation of gene expression in most of these species suggests that IF3s play roles in regulating gene expression in response to other environmental and developmental cues. In the plant Arabidopsis, two nuclear-encoded IF3s have been shown to localize to the chloroplasts, and the mRNA levels encoding these vary significantly in certain organ and tissue types and during several phases of development. Collectively, the accumulated data suggest that in about one quarter of photosynthetic prokaryotes and eukaryotes, IF3 gene families are used to regulate gene expression in addition to their traditional roles in translation initiation. Models for how this might be accomplished in prokaryotes versus eukaryotic plastids are presented.
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Affiliation(s)
- April D Nesbit
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA
- Department of Biology/Chemistry, Purdue University North Central, 1401 S. US 421, Westville, IN, 46391, USA
| | - Craig Whippo
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA
- Department of Natural Science, Dickinson State University, Dickinson, ND, 58601, USA
| | - Roger P Hangarter
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA
| | - David M Kehoe
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA.
- Indiana Molecular Biology Institute, Indiana University, Bloomington, IN, 47405, USA.
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Gunnelius L, Kurkela J, Hakkila K, Koskinen S, Parikainen M, Tyystjärvi T. The ω subunit of RNA polymerase is essential for thermal acclimation of the cyanobacterium Synechocystis sp. PCC 6803. PLoS One 2014; 9:e112599. [PMID: 25386944 PMCID: PMC4227741 DOI: 10.1371/journal.pone.0112599] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 10/09/2014] [Indexed: 01/26/2023] Open
Abstract
The rpoZ gene encodes the small ω subunit of RNA polymerase. A ΔrpoZ strain of the cyanobacterium Synechocystis sp. PCC 6803 grew well in standard conditions (constant illumination at 40 µmol photons m−2 s−1; 32°C; ambient CO2) but was heat sensitive and died at 40°C. In the control strain, 71 genes were at least two-fold up-regulated and 91 genes down-regulated after a 24-h treatment at 40°C, while in ΔrpoZ 394 genes responded to heat. Only 62 of these heat-responsive genes were similarly regulated in both strains, and 80% of heat-responsive genes were unique for ΔrpoZ. The RNA polymerase core and the primary σ factor SigA were down-regulated in the control strain at 40°C but not in ΔrpoZ. In accordance with reduced RNA polymerase content, the total RNA content of mild-heat-stress-treated cells was lower in the control strain than in ΔrpoZ. Light-saturated photosynthetic activity decreased more in ΔrpoZ than in the control strain upon mild heat stress. The amounts of photosystem II and rubisco decreased at 40°C in both strains while PSI and the phycobilisome antenna protein allophycocyanin remained at the same level as in standard conditions. The phycobilisome rod proteins, phycocyanins, diminished during the heat treatment in ΔrpoZ but not in the control strain, and the nblA1 and nblA2 genes (encode NblA proteins required for phycobilisome degradation) were up-regulated only in ΔrpoZ. Our results show that the ω subunit of RNAP is essential in heat stress because it is required for heat acclimation of diverse cellular processes.
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Affiliation(s)
- Liisa Gunnelius
- Department of Biochemistry, University of Turku, Turku, Finland
| | - Juha Kurkela
- Department of Biochemistry, University of Turku, Turku, Finland
| | - Kaisa Hakkila
- Department of Biochemistry, University of Turku, Turku, Finland
| | - Satu Koskinen
- Department of Biochemistry, University of Turku, Turku, Finland
| | | | - Taina Tyystjärvi
- Department of Biochemistry, University of Turku, Turku, Finland
- * E-mail:
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Mabbitt PD, Wilbanks SM, Eaton-Rye JJ. Structure and function of the hydrophilic Photosystem II assembly proteins: Psb27, Psb28 and Ycf48. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2014; 81:96-107. [PMID: 24656878 DOI: 10.1016/j.plaphy.2014.02.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Accepted: 02/16/2014] [Indexed: 05/23/2023]
Abstract
Photosystem II (PS II) is a macromolecular complex responsible for light-driven oxidation of water and reduction of plastoquinone as part of the photosynthetic electron transport chain found in thylakoid membranes. Each PS II complex is composed of at least 20 protein subunits and over 80 cofactors. The biogenesis of PS II requires further hydrophilic and membrane-spanning proteins which are not part of the active holoenzyme. Many of these biogenesis proteins make transient interactions with specific PS II assembly intermediates: sometimes these are essential for biogenesis while in other examples they are required for optimizing assembly of the mature complex. In this review the function and structure of the Psb27, Psb28 and Ycf48 hydrophilic assembly factors is discussed by combining structural, biochemical and physiological information. Each of these assembly factors has homologues in all oxygenic photosynthetic organisms. We provide a simple overview for the roles of these protein factors in cyanobacterial PS II assembly emphasizing their participation in both photosystem biogenesis and recovery from photodamage.
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Affiliation(s)
- Peter D Mabbitt
- Department of Biochemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - Sigurd M Wilbanks
- Department of Biochemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - Julian J Eaton-Rye
- Department of Biochemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand.
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27
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Mustila H, Allahverdiyeva Y, Isojärvi J, Aro EM, Eisenhut M. The bacterial-type [4Fe-4S] ferredoxin 7 has a regulatory function under photooxidative stress conditions in the cyanobacterium Synechocystis sp. PCC 6803. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1293-304. [PMID: 24780314 DOI: 10.1016/j.bbabio.2014.04.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 04/10/2014] [Accepted: 04/13/2014] [Indexed: 12/15/2022]
Abstract
Ferredoxins function as electron carrier in a wide range of metabolic and regulatory reactions. It is not clear yet, whether the multiplicity of ferredoxin proteins is also reflected in functional multiplicity in photosynthetic organisms. We addressed the biological function of the bacterial-type ferredoxin, Fed7 in the cyanobacterium Synechocystis sp. PCC 6803. The expression of fed7 is induced under low CO₂ conditions and further enhanced by additional high light treatment. These conditions are considered as promoting photooxidative stress, and prompted us to investigate the biological function of Fed7 under these conditions. Loss of Fed7 did not inhibit growth of the mutant strain Δfed7 but significantly modulated photosynthesis parameters when the mutant was grown under low CO₂ and high light conditions. Characteristics of the Δfed7 mutant included elevated chlorophyll and photosystem I levels as well as reduced abundance and activity of photosystem II. Transcriptional profiling of the mutant under low CO₂ conditions demonstrated changes in gene regulation of the carbon concentrating mechanism and photoprotective mechanisms such as the Flv2/4 electron valve, the PSII dimer stabilizing protein Sll0218, and chlorophyll biosynthesis. We conclude that the function of Fed7 is connected to coping with photooxidative stress, possibly by constituting a redox-responsive regulatory element in photoprotection. In photosynthetic eukaryotes domains homologous to Fed7 are exclusively found in chloroplast DnaJ-like proteins that are likely involved in remodeling of regulator protein complexes. It is conceivable that the regulatory function of Fed7 evolved in cyanobacteria and was recruited by Viridiplantae as the controller for the chloroplast DnaJ-like proteins.
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Affiliation(s)
- H Mustila
- Laboratory of Molecular Plant Biology, Department of Biochemistry, University of Turku, 20014 Turku, Finland.
| | - Y Allahverdiyeva
- Laboratory of Molecular Plant Biology, Department of Biochemistry, University of Turku, 20014 Turku, Finland.
| | - J Isojärvi
- Laboratory of Molecular Plant Biology, Department of Biochemistry, University of Turku, 20014 Turku, Finland.
| | - E M Aro
- Laboratory of Molecular Plant Biology, Department of Biochemistry, University of Turku, 20014 Turku, Finland.
| | - M Eisenhut
- Laboratory of Molecular Plant Biology, Department of Biochemistry, University of Turku, 20014 Turku, Finland.
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28
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Sobotka R. Making proteins green; biosynthesis of chlorophyll-binding proteins in cyanobacteria. PHOTOSYNTHESIS RESEARCH 2014; 119:223-32. [PMID: 23377990 DOI: 10.1007/s11120-013-9797-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Accepted: 01/10/2013] [Indexed: 05/20/2023]
Abstract
Chlorophyll (Chl) is an essential component of the photosynthetic apparatus. Embedded into Chl-binding proteins, Chl molecules play a central role in light harvesting and charge separation within the photosystems. It is critical for the photosynthetic cell to not only ensure the synthesis of a sufficient amount of new Chl-binding proteins but also avoids any misbalance between apoprotein synthesis and the formation of potentially phototoxic Chl molecules. According to the available data, Chl-binding proteins are translated on membrane bound ribosomes and their integration into the membrane is provided by the SecYEG/Alb3 translocon machinery. It appears that the insertion of Chl molecules into growing polypeptide is a prerequisite for the correct folding and finishing of Chl-binding protein synthesis. Although the Chl biosynthetic pathway is fairly well-described on the level of enzymatic steps, a link between Chl biosynthesis and the synthesis of apoproteins remains elusive. In this review, I summarize the current knowledge about this issue putting emphasis on protein-protein interactions. I present a model of the Chl biosynthetic pathway organized into a multi-enzymatic complex and physically attached to the SecYEG/Alb3 translocon. Localization of this hypothetical large biosynthetic centre in the cyanobacterial cell is also discussed as well as regulatory mechanisms coordinating the rate of Chl and apoprotein synthesis.
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Affiliation(s)
- Roman Sobotka
- Institute of Microbiology CAS, Opatovický mlyn, Třeboň, Czech Republic,
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29
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Hakkila K, Antal T, Rehman AU, Kurkela J, Wada H, Vass I, Tyystjärvi E, Tyystjärvi T. Oxidative stress and photoinhibition can be separated in the cyanobacterium Synechocystis sp. PCC 6803. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:217-25. [DOI: 10.1016/j.bbabio.2013.11.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 11/09/2013] [Accepted: 11/15/2013] [Indexed: 01/15/2023]
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30
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Gunnelius L, Hakkila K, Kurkela J, Wada H, Tyystjärvi E, Tyystjärvi T. The omega subunit of the RNA polymerase core directs transcription efficiency in cyanobacteria. Nucleic Acids Res 2014; 42:4606-14. [PMID: 24476911 PMCID: PMC3985657 DOI: 10.1093/nar/gku084] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The eubacterial RNA polymerase core, a transcription machinery performing DNA-dependent RNA polymerization, consists of two α subunits and β, β' and ω subunits. An additional σ subunit is recruited for promoter recognition and transcription initiation. Cyanobacteria, a group of eubacteria characterized by oxygenic photosynthesis, have a unique composition of the RNA polymerase (RNAP) core due to splitting of the β' subunit to N-terminal γ and C-terminal β' subunits. The physiological roles of the small ω subunit of RNAP, encoded by the rpoZ gene, are not yet completely understood in any bacteria. We found that although ω is non-essential in cyanobacteria, it has a major impact on the overall gene expression pattern. In ΔrpoZ strain, recruitment of the primary σ factor into the RNAP holoenzyme is inefficient, which causes downregulation of highly expressed genes and upregulation of many low-expression genes. Especially, genes encoding proteins of photosynthetic carbon concentrating and carbon fixing complexes were down, and the ΔrpoZ mutant showed low light-saturated photosynthetic activity and accumulated photoprotective carotenoids and α-tocopherol. The results indicate that the ω subunit facilitates the association of the primary σ factor with the RNAP core, thereby allowing efficient transcription of highly expressed genes.
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Affiliation(s)
- Liisa Gunnelius
- Department of Biochemistry, University of Turku, FIN-20014 Turku, Finland and Department of Life Sciences, University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan
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31
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Carmel D, Dahlström KM, Holmström M, Allahverdiyeva Y, Battchikova N, Aro EM, Salminen TA, Mulo P. Structural model, physiology and regulation of Slr0006 in Synechocystis PCC 6803. Arch Microbiol 2013; 195:727-36. [PMID: 24043215 DOI: 10.1007/s00203-013-0924-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 08/27/2013] [Accepted: 09/02/2013] [Indexed: 11/29/2022]
Abstract
The slr0006 gene of Synechocystis sp. PCC 6803 is upregulated at mRNA and protein level under carbon limitation. The T(N11)A motif in the upstream region of slr0006 is a binding site for transcriptional regulator NdhR, and accumulation of the Slr0006 protein in ndhR deletion mutant grown in high CO2 suggests that NdhR may be a negative regulator of slr0006. Accumulation requires photosynthetic electron transfer, because no Slr0006 was detected in darkness or in the presence of electron transfer inhibitors DCMU and DBMIB. Structural modeling of the Slr0006 protein suggests that it adopts Sua5/YciO/YrdC family fold, which is an α/β twisted open-sheet structure. Similar to the structurally known members of this protein family, the surface of Slr0006 contains positively charged cavity indicating a possible binding site for RNA or nucleotides. Moreover, Slr0006 was co-localized with 30S ribosomal proteins and rRNA, suggesting involvement in processes linked to protein synthesis.
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Affiliation(s)
- Dalton Carmel
- Department of Biochemistry, Molecular Plant Biology, University of Turku, 20014, Turku, Finland
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Tyystjärvi T, Huokko T, Rantamäki S, Tyystjärvi E. Impact of different group 2 sigma factors on light use efficiency and high salt stress in the cyanobacterium Synechocystis sp. PCC 6803. PLoS One 2013; 8:e63020. [PMID: 23638176 PMCID: PMC3637157 DOI: 10.1371/journal.pone.0063020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2013] [Accepted: 03/27/2013] [Indexed: 11/24/2022] Open
Abstract
Sigma factors of RNA polymerase recognize promoters and have a central role in controlling transcription initiation and acclimation to changing environmental conditions. The cyanobacterium Synechocystis sp. PCC 6803 encodes four non-essential group 2 sigma factors, SigB, SigC, SigD and SigE that closely resemble the essential SigA factor. Three out of four group 2 sigma factors were simultaneously inactivated and acclimation responses of the triple inactivation strains were studied. All triple inactivation strains grew slowly in low light, and our analysis suggests that the reason is a reduced capacity to adjust the perception of light. Simultaneous inactivation of SigB and SigD hampered growth also in high light. SigB is the most important group 2 sigma factor for salt acclimation, and elimination of all the other group 2 sigma factors slightly improved the salt tolerance of Synechocystis. Presence of only SigE allowed full salt acclimation including up-regulation of hspA and ggpS genes, but more slowly than SigB. Cells with only SigD acclimated to high salt but the acclimation processes differed from those of the control strain. Presence of only SigC prevented salt acclimation.
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Affiliation(s)
- Taina Tyystjärvi
- Molecular Plant Biology, Department of Biochemistry and Food Chemistry, University of Turku, Turku, Finland.
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33
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Sakurai I, Stazic D, Eisenhut M, Vuorio E, Steglich C, Hess WR, Aro EM. Positive regulation of psbA gene expression by cis-encoded antisense RNAs in Synechocystis sp. PCC 6803. PLANT PHYSIOLOGY 2012; 160:1000-10. [PMID: 22858634 PMCID: PMC3461525 DOI: 10.1104/pp.112.202127] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The D1 protein of photosystem II in the thylakoid membrane of photosynthetic organisms is encoded by psbA genes, which in cyanobacteria occur in the form of a small gene family. Light-dependent up-regulation of psbA gene expression is crucial to ensure the proper replacement of the D1 protein. To gain a high level of gene expression, psbA transcription can be enhanced by several orders of magnitude. Recent transcriptome analyses demonstrated a high number of cis-encoded antisense RNAs (asRNAs) in bacteria, but very little is known about their possible functions. Here, we show the presence of two cis-encoded asRNAs (PsbA2R and PsbA3R) of psbA2 and psbA3 from Synechocystis sp. PCC 6803. These asRNAs are located in the 5' untranslated region of psbA2 and psbA3 genes. Their expression becomes up-regulated by light and down-regulated by darkness, similar to their target mRNAs. In the PsbA2R-suppressing strain [PsbA2R(-)], the amount of psbA2 mRNA was only about 50% compared with the control strain. Likewise, we identified a 15% lowered activity of photosystem II and a reduced amount of the D1 protein in PsbA2R(-) compared with the control strain. The function of PsbA2R in the stabilization of psbA2 mRNA was shown from in vitro RNase E assay when the AU box and the ribosome-binding site in the 5' untranslated region of psbA2 mRNA were both covered by PsbA2R. These results add another layer of complexity to the mechanisms that contribute to psbA gene expression and show PsbA2R as a positively acting factor to achieve a maximum level of D1 synthesis.
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Nikkinen HL, Hakkila K, Gunnelius L, Huokko T, Pollari M, Tyystjärvi T. The SigB σ factor regulates multiple salt acclimation responses of the cyanobacterium Synechocystis sp. PCC 6803. PLANT PHYSIOLOGY 2012; 158:514-23. [PMID: 22095043 PMCID: PMC3252095 DOI: 10.1104/pp.111.190058] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Changing of principal σ factor in RNA polymerase holoenzyme to a group 2 σ factor redirects transcription when cyanobacteria acclimate to suboptimal environmental conditions. The group 2 sigma factor SigB was found to be important for the growth of the cyanobacterium Synechocystis sp. PCC 6803 in high-salt (0.7 m NaCl) stress but not in mild heat stress at 43°C although the expression of the sigB gene was similarly highly, but only transiently up-regulated at both conditions. The SigB factor was found to regulate many salt acclimation processes. The amount of glucosylglycerol-phosphate synthase, a key enzyme in the production of the compatible solute glucosylglycerol, was lower in the inactivation strain ΔsigB than in the control strain. Addition of the compatible solute trehalose almost completely restored the growth of the ΔsigB strain at 0.7 m NaCl. High-salt conditions lowered the chlorophyll and phycobilin contents of the cells while protective carotenoid pigments, especially zeaxanthin and myxoxanthophyll, were up-regulated in the control strain. These carotenoids were up-regulated in the ΔsigCDE strain (SigB is the only functional group 2 σ factor) and down-regulated in the ΔsigB strain under standard conditions. In addition, the HspA heat shock protein was less abundant and more abundant in the ΔsigB and ΔsigCDE strains, respectively, than in the control strain in high-salt conditions. Some cellular responses are common to heat and salt stresses, but pretreatment with mild heat did not protect cells against salt shock although protection against heat shock was evident.
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35
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Light-dependent attenuation of phycoerythrin gene expression reveals convergent evolution of green light sensing in cyanobacteria. Proc Natl Acad Sci U S A 2011; 108:18542-7. [PMID: 22042852 DOI: 10.1073/pnas.1107427108] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The colorful process of chromatic acclimation allows many cyanobacteria to change their pigmentation in response to ambient light color changes. In red light, cells produce red-absorbing phycocyanin (PC), whereas in green light, green-absorbing phycoerythrin (PE) is made. Controlling these pigment levels increases fitness by optimizing photosynthetic activity in different light color environments. The light color sensory system controlling PC expression is well understood, but PE regulation has not been resolved. In the filamentous cyanobacterium Fremyella diplosiphon UTEX 481, two systems control PE synthesis in response to light color. The first is the Rca pathway, a two-component system controlled by a phytochrome-class photoreceptor, which transcriptionally represses cpeCDESTR (cpeC) expression during growth in red light. The second is the Cgi pathway, which has not been characterized. We determined that the Cgi system also regulates PE synthesis by repressing cpeC expression in red light, but acts posttranscriptionally, requiring the region upstream of the CpeC translation start codon. cpeC RNA stability was comparable in F. diplosiphon cells grown in red and green light, and a short transcript that included the 5' region of cpeC was detected, suggesting that the Cgi system operates by transcription attenuation. The roles of four predicted stem-loop structures within the 5' region of cpeC RNA were analyzed. The putative stem-loop 31 nucleotides upstream of the translation start site was required for Cgi system function. Thus, the Cgi system appears to be a unique type of signal transduction pathway in which the attenuation of cpeC transcription is regulated by light color.
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36
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Adam Z, Frottin F, Espagne C, Meinnel T, Giglione C. Interplay between N-terminal methionine excision and FtsH protease is essential for normal chloroplast development and function in Arabidopsis. THE PLANT CELL 2011; 23:3745-60. [PMID: 22010036 PMCID: PMC3229147 DOI: 10.1105/tpc.111.087239] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
N-terminal methionine excision (NME) is the earliest modification affecting most proteins. All compartments in which protein synthesis occurs contain dedicated NME machinery. Developmental defects induced in Arabidopsis thaliana by NME inhibition are accompanied by increased proteolysis. Although increasing evidence supports a connection between NME and protein degradation, the identity of the proteases involved remains unknown. Here we report that chloroplastic NME (cNME) acts upstream of the FtsH protease complex. Developmental defects and higher sensitivity to photoinhibition associated with the ftsh2 mutation were abolished when cNME was inhibited. Moreover, the accumulation of D1 and D2 proteins of the photosystem II reaction center was always dependent on the prior action of cNME. Under standard light conditions, inhibition of chloroplast translation induced accumulation of correctly NME-processed D1 and D2 in a ftsh2 background, implying that the latter is involved in protein quality control, and that correctly NME-processed D1 and D2 are turned over primarily by the thylakoid FtsH protease complex. By contrast, inhibition of cNME compromises the specific N-terminal recognition of D1 and D2 by the FtsH complex, whereas the unprocessed forms are recognized by other proteases. Our results highlight the tight functional interplay between NME and the FtsH protease complex in the chloroplast.
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Affiliation(s)
- Zach Adam
- Centre National de la Recherche Scientifique, Campus de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
- Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Frédéric Frottin
- Centre National de la Recherche Scientifique, Campus de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
| | - Christelle Espagne
- Centre National de la Recherche Scientifique, Campus de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
| | - Thierry Meinnel
- Centre National de la Recherche Scientifique, Campus de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
| | - Carmela Giglione
- Centre National de la Recherche Scientifique, Campus de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
- Address correspondence to
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Grasse N, Mamedov F, Becker K, Styring S, Rögner M, Nowaczyk MM. Role of novel dimeric Photosystem II (PSII)-Psb27 protein complex in PSII repair. J Biol Chem 2011; 286:29548-55. [PMID: 21737447 DOI: 10.1074/jbc.m111.238394] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The multisubunit membrane protein complex Photosystem II (PSII) catalyzes one of the key reactions in photosynthesis: the light-driven oxidation of water. Here, we focus on the role of the Psb27 assembly factor, which is involved in biogenesis and repair after light-induced damage of the complex. We show that Psb27 is essential for the survival of cyanobacterial cells grown under stress conditions. The combination of cold stress (30 °C) and high light stress (1000 μmol of photons × m(-2) × s(-1)) led to complete inhibition of growth in a Δpsb27 mutant strain of the thermophilic cyanobacterium Thermosynechococcus elongatus, whereas wild-type cells continued to grow. Moreover, Psb27-containing PSII complexes became the predominant PSII species in preparations from wild-type cells grown under cold stress. Two different PSII-Psb27 complexes were isolated and characterized in this study. The first complex represents the known monomeric PSII-Psb27 species, which is involved in the assembly of PSII. Additionally, a novel dimeric PSII-Psb27 complex could be allocated in the repair cycle, i.e. in processes after inactivation of PSII, by (15)N pulse-label experiments followed by mass spectrometry analysis. Comparison with the corresponding PSII species from Δpsb27 mutant cells showed that Psb27 prevented the release of manganese from the previously inactivated complex. These results indicate a more complex role of the Psb27 protein within the life cycle of PSII, especially under stress conditions.
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Affiliation(s)
- Nicole Grasse
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr-Universität Bochum, Bochum, Germany
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38
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Mulo P, Sakurai I, Aro EM. Strategies for psbA gene expression in cyanobacteria, green algae and higher plants: from transcription to PSII repair. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1817:247-57. [PMID: 21565160 DOI: 10.1016/j.bbabio.2011.04.011] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 04/06/2011] [Accepted: 04/07/2011] [Indexed: 11/26/2022]
Abstract
The Photosystem (PS) II of cyanobacteria, green algae and higher plants is prone to light-induced inactivation, the D1 protein being the primary target of such damage. As a consequence, the D1 protein, encoded by the psbA gene, is degraded and re-synthesized in a multistep process called PSII repair cycle. In cyanobacteria, a small gene family codes for the various, functionally distinct D1 isoforms. In these organisms, the regulation of the psbA gene expression occurs mainly at the level of transcription, but the expression is fine-tuned by regulation of translation elongation. In plants and green algae, the D1 protein is encoded by a single psbA gene located in the chloroplast genome. In chloroplasts of Chlamydomonas reinhardtii the psbA gene expression is strongly regulated by mRNA processing, and particularly at the level of translation initiation. In chloroplasts of higher plants, translation elongation is the prevalent mechanism for regulation of the psbA gene expression. The pre-existing pool of psbA transcripts forms translation initiation complexes in plant chloroplasts even in darkness, while the D1 synthesis can be completed only in the light. Replacement of damaged D1 protein requires also the assistance by a number of auxiliary proteins, which are encoded by the nuclear genome in green algae and higher plants. Nevertheless, many of these chaperones are conserved between prokaryotes and eukaryotes. Here, we describe the specific features and fundamental differences of the psbA gene expression and the regeneration of the PSII reaction center protein D1 in cyanobacteria, green algae and higher plants. This article is part of a Special Issue entitled Photosystem II.
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Affiliation(s)
- Paula Mulo
- Department of Biochemistry and Food Chemistry, University of Turku, Finland.
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39
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Nishiyama Y, Allakhverdiev SI, Murata N. Protein synthesis is the primary target of reactive oxygen species in the photoinhibition of photosystem II. PHYSIOLOGIA PLANTARUM 2011; 142:35-46. [PMID: 21320129 DOI: 10.1111/j.1399-3054.2011.01457.x] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Photoinhibition of photosystem II (PSII) occurs when the rate of photodamage to PSII exceeds the rate of the repair of photodamaged PSII. Recent examination of photoinhibition by separate determinations of photodamage and repair has revealed that the rate of photodamage to PSII is directly proportional to the intensity of incident light and that the repair of PSII is particularly sensitive to the inactivation by reactive oxygen species (ROS). The ROS-induced inactivation of repair is attributable to the suppression of the synthesis de novo of proteins, such as the D1 protein, that are required for the repair of PSII at the level of translational elongation. Furthermore, molecular analysis has revealed that the ROS-induced suppression of protein synthesis is associated with the specific inactivation of elongation factor G via the formation of an intramolecular disulfide bond. Impairment of various mechanisms that protect PSII against photoinhibition, including photorespiration, thermal dissipation of excitation energy, and the cyclic transport of electrons, decreases the rate of repair of PSII via the suppression of protein synthesis. In this review, we present a newly established model of the mechanism and the physiological significance of repair in the regulation of the photoinhibition of PSII.
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Affiliation(s)
- Yoshitaka Nishiyama
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering and Institute for Environmental Science and Technology, Saitama University, Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan.
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Sipilä TP, Väisänen P, Paulin L, Yrjälä K. Sphingobium sp. HV3 degrades both herbicides and polyaromatic hydrocarbons using ortho- and meta-pathways with differential expression shown by RT-PCR. Biodegradation 2010; 21:771-84. [DOI: 10.1007/s10532-010-9342-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Accepted: 02/09/2010] [Indexed: 11/29/2022]
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Mulo P, Sicora C, Aro EM. Cyanobacterial psbA gene family: optimization of oxygenic photosynthesis. Cell Mol Life Sci 2009; 66:3697-710. [PMID: 19644734 PMCID: PMC2776144 DOI: 10.1007/s00018-009-0103-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Revised: 07/03/2009] [Accepted: 07/10/2009] [Indexed: 02/06/2023]
Abstract
The D1 protein of Photosystem II (PSII), encoded by the psbA genes, is an indispensable component of oxygenic photosynthesis. Due to strongly oxidative chemistry of PSII water splitting, the D1 protein is prone to constant photodamage requiring its replacement, whereas most of the other PSII subunits remain ordinarily undamaged. In cyanobacteria, the D1 protein is encoded by a psbA gene family, whose members are differentially expressed according to environmental cues. Here, the regulation of the psbA gene expression is first discussed with emphasis on the model organisms Synechococcus sp. and Synechocystis sp. Then, a general classification of cyanobacterial D1 isoforms in various cyanobacterial species into D1m, D1:1, D1:2, and D1' forms depending on their expression pattern under acclimated growth conditions and upon stress is discussed, taking into consideration the phototolerance of different D1 forms and the expression conditions of respective members of the psbA gene family.
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Affiliation(s)
- Paula Mulo
- Laboratory of Plant Physiology and Molecular Biology, Department of Biology, Biocity A, University of Turku, 20520 Turku, Finland.
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Kojima K, Motohashi K, Morota T, Oshita M, Hisabori T, Hayashi H, Nishiyama Y. Regulation of translation by the redox state of elongation factor G in the cyanobacterium Synechocystis sp. PCC 6803. J Biol Chem 2009; 284:18685-91. [PMID: 19447882 PMCID: PMC2707220 DOI: 10.1074/jbc.m109.015131] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Revised: 05/14/2009] [Indexed: 01/17/2023] Open
Abstract
Elongation factor G (EF-G), a key protein in translational elongation, was identified as a primary target of inactivation by reactive oxygen species within the translational machinery of the cyanobacterium Synechocystis sp. PCC 6803 (Kojima, K., Oshita, M., Nanjo, Y., Kasai, K., Tozawa, Y., Hayashi, H., and Nishiyama, Y. (2007) Mol. Microbiol. 65, 936-947). In the present study, we found that inactivation of EF-G (Slr1463) by H(2)O(2) was attributable to the oxidation of two specific cysteine residues and formation of a disulfide bond. Substitution of these cysteine residues by serine residues protected EF-G from inactivation by H(2)O(2) and allowed the EF-G to mediate translation in a translation system in vitro that had been prepared from Synechocystis. The disulfide bond in oxidized EF-G was reduced by thioredoxin, and the resultant reduced form of EF-G regained the activity to mediate translation in vitro. Western blotting analysis showed that levels of the oxidized form of EF-G increased under strong light in a mutant that lacked NADPH-thioredoxin reductase, indicating that EF-G is reduced by thioredoxin in vivo. These observations suggest that the translational machinery is regulated by the redox state of EF-G, which is oxidized by reactive oxygen species and reduced by thioredoxin, a transmitter of reducing signals generated by the photosynthetic transport of electrons.
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Affiliation(s)
- Kouji Kojima
- From the Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
- Venture Business Laboratory, Ehime University, 3 Bunkyo-cho, Matsuyama 790-8577, Japan
| | - Ken Motohashi
- the Chemical Resources Laboratory, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan and
| | - Takuya Morota
- From the Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | | | - Toru Hisabori
- the Chemical Resources Laboratory, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan and
| | - Hidenori Hayashi
- the Graduate School of Science and Engineering
- Cell-Free Science and Technology Research Center, and
- Venture Business Laboratory, Ehime University, 3 Bunkyo-cho, Matsuyama 790-8577, Japan
| | - Yoshitaka Nishiyama
- From the Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
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Simultaneous inactivation of sigma factors B and D interferes with light acclimation of the cyanobacterium Synechocystis sp. strain PCC 6803. J Bacteriol 2009; 191:3992-4001. [PMID: 19363110 DOI: 10.1128/jb.00132-09] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In cyanobacteria, gene expression is regulated mainly at the level of transcription initiation, which is mediated by the RNA polymerase holoenzyme. The RNA polymerase core is catalytically active, while the sigma factor recognizes promoter sequences. Group 2 sigma factors are similar to the principal sigma factor but are nonessential. Group 2 sigma factors SigB and SigD are structurally the most similar sigma factors in Synechocystis sp. strain PCC 6803. Under standard growth conditions, simultaneous inactivation of sigB and sigD genes did not affect the growth, but the photosynthesis and growth of the DeltasigBD strain were slower than in the control strain at double light intensity. Light-saturated electron transfer rates and the fluorescence and thermoluminescence measurements showed that photosynthetic light reactions are fully functional in the DeltasigBD strain, but absorption and 77 K emission spectra measurements suggest that the light-harvesting system of the DeltasigBD strain does not acclimate normally to higher light intensity. Furthermore, the DeltasigBD strain is more sensitive to photoinhibition under bright light because impaired upregulation of psbA genes leads to insufficient PSII repair.
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Wang Y, Xu W, Chitnis PR. Identification and bioinformatic analysis of the membrane proteins of synechocystis sp. PCC 6803. Proteome Sci 2009; 7:11. [PMID: 19320970 PMCID: PMC2666656 DOI: 10.1186/1477-5956-7-11] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2008] [Accepted: 03/25/2009] [Indexed: 01/13/2023] Open
Abstract
Background The membranes of Synechocystis sp. PCC 6803 play a central role in photosynthesis, respiration and other important metabolic pathways. Comprehensive identification of the membrane proteins is of importance for a better understanding of the diverse functions of its unique membrane structures. Up to date, approximately 900 known or predicted membrane proteins, consisting 24.5% of Synechocystis sp. PCC 6803 proteome, have been indentified by large-scale proteomic studies. Results To resolve more membrane proteins on 2-D gels for mass spectrometry identification, we separated integral proteins from membrane associated proteins and collected them as the integral and peripheral fractions, respectively. In total, 95 proteins in the peripheral fraction and 29 proteins in the integral fraction were identified, including the 5 unique proteins that were not identified by any previous studies. Bioinformatic analysis revealed that the identified proteins can be functionally classified into 14 distinct groups according to the cellular functions annotated by Cyanobase, including the two largest groups hypothetical and unknown, and photosynthesis and respiration. Homology analysis indicates that the identified membrane proteins are more conserved than the rest of the proteome. Conclusion The proteins identified in this study combined with other published proteomic data provide the most comprehensive Synechocystis proteome catalog, which will serve as a useful reference for further detailed studies to address protein functions through both traditional gene-by-gene and systems biology approaches.
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Affiliation(s)
- Yingchun Wang
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, 50011, USA.
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Bentley FK, Luo H, Dilbeck P, Burnap RL, Eaton-Rye JJ. Effects of inactivating psbM and psbT on photodamage and assembly of photosystem II in Synechocystis sp. PCC 6803. Biochemistry 2008; 47:11637-46. [PMID: 18834146 DOI: 10.1021/bi800804h] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PsbM and PsbT have been assigned to electron densities on both photosystem II (PSII) monomers at the PSII dimer interface in X-ray crystallographic structures from Thermosynechoccocus elongatus and T. vulcanus. Our results show that removal of either or both proteins from Synechocystis sp. PCC 6803 resulted in photoautotrophic strains but the DeltaPsbM:DeltaPsbT mutant did not form stable dimers. A CP43-less PSII monomer accumulated in both single mutants, although absence of PsbT destabilized PSII to a greater extent than removing PsbM. Additionally, DeltaPsbT cells exhibited slowed electron transfer between the plastoquinone electron acceptors, Q(A) and Q(B); however, S-state cycling in both mutants was similar to wild type. Oxygen evolution in these mutants rapidly inactivated following exposure to high light where recovery required protein synthesis and could proceed in the dark in DeltaPsbM cells but required light in DeltaPsbT cells. Interestingly, the extent of recovery of oxygen-evolving activity was greatest in the DeltaPsbM:DeltaPsbT strain. We also found recovery required Psb27 in DeltaPsbT cells although, under our conditions, the DeltaPsb27 strain remained similar to wild type. In contrast, the DeltaPsbM:DeltaPsb27 mutant could not assemble PSII beyond a CP43-minus intermediate. Our results suggest essential roles for Psb27 in biogenesis in the DeltaPsbM strain and for repair from photodamage in cells lacking PsbT.
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Affiliation(s)
- Fiona K Bentley
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
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Pollari M, Gunnelius L, Tuominen I, Ruotsalainen V, Tyystjärvi E, Salminen T, Tyystjärvi T. Characterization of single and double inactivation strains reveals new physiological roles for group 2 sigma factors in the cyanobacterium Synechocystis sp. PCC 6803. PLANT PHYSIOLOGY 2008; 147:1994-2005. [PMID: 18539776 PMCID: PMC2492616 DOI: 10.1104/pp.108.122713] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Accepted: 05/28/2008] [Indexed: 05/20/2023]
Abstract
Cyanobacteria are eubacteria that perform oxygenic photosynthesis like plants. The initiation of transcription, mediated by the RNA polymerase holoenzyme, is the main determinant of gene regulation in eubacteria. The sigma factor of the RNA polymerase holoenzyme is responsible for the recognition of a promoter sequence. In the cyanobacterium Synechocystis sp. PCC 6803, the primary sigma factor, SigA, is essential for cell viability. The SigB, SigC, SigD, and SigE factors show significant sequence similarity with the SigA factor but are nonessential. In this study, we have used homology modeling to construct a three-dimensional model of Synechocystis RNA polymerase holoenzyme and all group 1 and 2 sigma factors. According to the models, the overall three-dimensional structures of group 1 and 2 sigma factors are similar, the SigB and SigD factors being the most similar ones. In addition, we have constructed a complete set of group 2 sigma factor double inactivation strains, DeltasigBC, DeltasigBD, DeltasigBE, DeltasigCD, DeltasigCE, and DeltasigDE. All double mutants grow well under standard conditions, but differences are observed in stress conditions. The transition from lag phase to exponential growth is slow in the DeltasigBD strain, and all strains lacking the SigD factor were found to be sensitive to bright light. Furthermore, all group 2 sigma factors were found to be involved in acclimation to salt- or sorbitol-induced osmotic stresses.
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Affiliation(s)
- Maija Pollari
- Plant Physiology and Molecular Biology, Department of Biology, University of Turku, FI-20014 Turku, Finland
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Tuominen I, Pollari M, Aguirre von Wobeser E, Tyystjärvi E, Ibelings BW, Matthijs HCP, Tyystjärvi T. Sigma factor SigC is required for heat acclimation of the cyanobacterium Synechocystis sp. strain PCC 6803. FEBS Lett 2007; 582:346-50. [PMID: 18166156 DOI: 10.1016/j.febslet.2007.12.030] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 12/14/2007] [Accepted: 12/18/2007] [Indexed: 11/28/2022]
Abstract
The role of the primary-like sigma factor SigC was studied in Synechocystis. Under high temperature stress (48 degrees C) the DeltasigC inactivation strain showed a lower survival rate than the control strain. The DeltasigC strain grew poorly at 43 degrees C in liquid cultures under normal air. However, change to 3% CO(2) enhanced growth of DeltasigC at 43 degrees C. Differences in expression of many genes related to the carbon concentrating mechanisms between the control and the DeltasigC strain were recorded with a genome-wide DNA microarray. We suggest that low solubility of CO2 at high temperature is one of the factors contributing to the poor thermotolerance of the DeltasigC strain.
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Affiliation(s)
- Ilona Tuominen
- Plant Physiology and Molecular Biology, Department of Biology, University of Turku, Turku, Finland
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Kojima K, Oshita M, Nanjo Y, Kasai K, Tozawa Y, Hayashi H, Nishiyama Y. Oxidation of elongation factor G inhibits the synthesis of the D1 protein of photosystem II. Mol Microbiol 2007; 65:936-47. [PMID: 17617168 DOI: 10.1111/j.1365-2958.2007.05836.x] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Oxidative stress inhibits the repair of photodamaged photosystem II (PSII). This inhibition is due initially to the suppression, by reactive oxygen species (ROS), of the synthesis de novo of proteins that are required for the repair of PSII, such as the D1 protein, at the level of translational elongation. To investigate in vitro the mechanisms whereby ROS inhibit translational elongation, we developed a translation system in vitro from the cyanobacterium Synechocystis sp. PCC 6803. The synthesis of the D1 protein in vitro was inhibited by exogenous H2O2. However, the addition of reduced forms of elongation factor G (EF-G), which is known to be particularly sensitive to oxidation, was able to reverse the inhibition of translation. By contrast, the oxidized forms of EF-G failed to restore translational activity. Furthermore, the overexpression of EF-G of Synechocystis in another cyanobacterium Synechococcus sp. PCC 7942 increased the tolerance of cells to H2O2 in terms of protein synthesis. These observations suggest that EF-G might be the primary target, within the translational machinery, of inhibition by ROS.
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Affiliation(s)
- Kouji Kojima
- Cell-Free Science and Technology Research Center, and Venture Business Laboratory, Ehime University, Bunkyo-cho, Matsuyama 790-8577, Japan
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Watanabe S, Kobayashi T, Saito M, Sato M, Nimura-Matsune K, Chibazakura T, Taketani S, Nakamoto H, Yoshikawa H. Studies on the role of HtpG in the tetrapyrrole biosynthesis pathway of the cyanobacterium Synechococcus elongatus PCC 7942. Biochem Biophys Res Commun 2007; 352:36-41. [PMID: 17107658 DOI: 10.1016/j.bbrc.2006.10.144] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2006] [Accepted: 10/25/2006] [Indexed: 11/26/2022]
Abstract
In cyanobacterium Synechococcus elongatus PCC 7942, we observed that htpG-overexpression caused remarkable growth inhibition. In addition, subcellular fractionation experiments showed that HtpG was localized in the membrane fraction. To understand its function in cyanobacteria, we carried out yeast two-hybrid screening to identify specific proteins interacting with HtpG, and found out, HemE, uroporphyrinogen decarboxylase. When compared to the wild-type strain, the htpG-null mutant and -overexpressing strains exhibited higher and lower cytosolic HemE activity, based on the coproporphyrin production, respectively. These results strongly suggest that HtpG is involved in the regulation of tetrapyrrole biosynthesis through interacting with HemE protein.
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Affiliation(s)
- Satoru Watanabe
- Department of Bioscience, Tokyo University of Agriculture, Sakuragaoka 1-1-1, Setagaya-ku, Tokyo 156-8502, Japan
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Stelljes C, Koenig F. Specific binding of D1 protein degradation products to the psbAI promoter in Synechococcus sp. strain PCC 7942. J Bacteriol 2006; 189:1722-6. [PMID: 17189360 PMCID: PMC1855774 DOI: 10.1128/jb.01428-06] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The D1:1 protein and its potentially occurring degradation products were overexpressed in Escherichia coli. Protein-DNA interaction is shown for the promoter region of psbAI. The D1:1 degradation products may be involved in transcription regulation of psbAI by binding in the promoter region. Additionally, C-terminal fragments of the D1 protein bind to a sequence with similarity to isiB, a gene which encodes a flavodoxin-like protein.
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Affiliation(s)
- Christian Stelljes
- Molekulare Pflanzenphysiologie, Universität Bremen, Leobener Str., 28359 Bremen, Germany
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