Dark complexes of the Calvin-Benson cycle in a physiological perspective

Seminars in Cell and Developmental Biology, Journal Year: 2023, Volume and Issue: 155, P. 48 - 58

Published: March 6, 2023

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK) are two enzymes of the Calvin Benson cycle that stand out for some peculiar properties they have in common: (i) both use products light reactions catalysis (NADPH GAPDH, ATP PRK), (ii) light-regulated through thioredoxins (iii) involved formation regulatory supramolecular complexes dark or low photosynthetic conditions, with without protein CP12. In complexes, transiently inactivated but ready to recover full activity after complex dissociation. Fully active GAPDH PRK large excess functioning Calvin-Benson cycle, can limit upon formation. Complex dissociation contributes induction. CP12 also controls concentration model organisms like Arabidopsis thaliana Chlamydomonas reinhardtii. The review combines vivo vitro data into an integrated physiological view role regulation photosynthesis.

Language: Английский

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Structure of the Calvin-Benson-Bassham sedoheptulose-1,7-bisphosphatase from the model microalga Chlamydomonas reinhardtii

Published: March 11, 2025

The Calvin-Benson-Bassham cycle (CBBC) performs carbon fixation in photosynthetic organisms. Among the eleven enzymes that participate pathway, sedoheptulose-1,7-bisphosphatase (SBPase) is expressed photo-autotrophs and catalyzes hydrolysis of sedoheptulose-1,7- bisphosphate (SBP) to sedoheptulose-7-phosphate (S7P). SBPase, along with nine other CBBC, contributes regeneration ribulose-1,5-bisphosphate, carbon-fixing co- substrate used by ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). metabolic role SBPase restricted a recent study revealed three-dimensional structure from moss Physcomitrium patens was found be similar fructose-1,6- bisphosphatase (FBPase), an enzyme involved both CBBC neoglucogenesis. In this we report first chlorophyte, model unicellular green microalga Chlamydomonas reinhardtii . By combining experimental computational structural analyses, describe topology, conformations quaternary ( Cr SBPase). We identify active site residues locate sites redox- phospho-post- translational modifications contribute enzymatic functions. Finally, observe adopts distinct oligomeric states may dynamically control its activity.

Language: Английский

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Structure of the Calvin-Benson-Bassham sedoheptulose-1,7-bisphosphatase from the model microalga Chlamydomonas reinhardtii

eLife, Journal Year: 2025, Volume and Issue: 12

Published: April 1, 2025

The Calvin-Benson-Bassham cycle (CBBC) performs carbon fixation in photosynthetic organisms. Among the eleven enzymes that participate pathway, sedoheptulose-1,7-bisphosphatase (SBPase) is expressed photo-autotrophs and catalyzes hydrolysis of sedoheptulose-1,7-bisphosphate (SBP) to sedoheptulose-7-phosphate (S7P). SBPase, along with nine other CBBC, contributes regeneration ribulose-1,5-bisphosphate, carbon-fixing co-substrate used by ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). metabolic role SBPase restricted a recent study revealed three-dimensional structure from moss Physcomitrium patens was found be similar fructose-1,6-bisphosphatase (FBPase), an enzyme involved both CBBC neoglucogenesis. In this we report first chlorophyte, model unicellular green microalga Chlamydomonas reinhardtii . By combining experimental computational structural analyses, describe topology, conformations, quaternary ( Cr SBPase). We identify active site residues locate sites redox- phospho-post-translational modifications contribute enzymatic functions. Finally, observe adopts distinct oligomeric states may dynamically control its activity.

Language: Английский

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CLPB3 is required for the removal of chloroplast protein aggregates and thermotolerance in Chlamydomonas

Journal of Experimental Botany, Journal Year: 2023, Volume and Issue: 74(12), P. 3714 - 3728

Published: March 23, 2023

In the cytosol of plant cells, heat-induced protein aggregates are resolved by CASEIN LYTIC PROTEINASE/HEAT SHOCK PROTEIN 100 (CLP/HSP100) chaperone family member HSP101, which is essential for thermotolerance. For chloroplast CLPB3 this less clear, with controversial reports on its role in conferring To shed light issue, we have characterized two clpb3 mutants Chlamydomonas reinhardtii. We show that required resolving containing stromal TRIGGER FACTOR (TIG1) and small heat shock proteins 22E/F (HSP22E/F) vivo, thermotolerance under stress. Although accumulation similar to HSP70B ambient conditions, observed no prominent constitutive phenotypes. However, found decreased PLASTID RIBOSOMAL L1 (PRPL1) increased protease DEG1C mutants, suggesting a reduction synthesis capacity an increase proteolytic may compensate loss function. Under was distributed throughout chloroplast, but reorganized into foci upon stress, mostly disappeared during recovery. were localized next HSP22E/F, accumulated largely near thylakoid membranes. This suggests possible disentangling from membrane system.

Language: Английский

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Challenges and advances towards the rational design of microalgal synthetic promoters in Chlamydomonas reinhardtii

Journal of Experimental Botany, Journal Year: 2023, Volume and Issue: 74(13), P. 3833 - 3850

Published: April 7, 2023

Microalgae hold enormous potential to provide a safe and sustainable source of high-value compounds, acting as carbon-fixing biofactories that could help mitigate rapidly progressing climate change. Bioengineering microalgal strains will be key optimizing modifying their metabolic outputs, render them competitive with established industrial biotechnology hosts, such bacteria or yeast. To achieve this, precise tuneable control over transgene expression essential, which would require the development rational design synthetic promoters strategy. Among green microalgae, Chlamydomonas reinhardtii represents reference species for bioengineering biology; however, repertoire functional this species, microalgae generally, is limited in comparison other commercial chassis, emphasizing need expand current gene toolbox. Here, we discuss state-of-the-art promoter analyses, highlight areas research required advance C. reinhardtii. In particular, exemplify high-throughput studies performed model systems applicable propose novel approaches interrogating algal promoters. We lastly outline major limitations hindering development, while providing suggestions perspectives how overcome them.

Language: Английский

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Chassis engineering for high light tolerance in microalgae and cyanobacteria

Critical Reviews in Biotechnology, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 19

Published: July 10, 2024

Oxygenic photosynthesis in microalgae and cyanobacteria is considered an important chassis to accelerate energy transition mitigate global warming. Currently, cultivation systems for photosynthetic microbes large-scale applications encountered excessive light exposure stress. High stress can: affect efficiency, reduce productivity, limit cell growth, even cause death. Deciphering photoprotection mechanisms constructing high-light tolerant have been recent research focuses. In this review, we first briefly introduce the self-protection of common response high These mainly include: avoiding excess absorption, dissipating excitation energy, quenching high-energy electrons, ROS detoxification, PSII repair. We focus on species-specific differences these as well advancements. Then, review engineering strategies creating chassis, such as: reducing size light-harvesting antenna, optimizing non-photochemical quenching, electron transport, enhancing Finally, propose a comprehensive exploration mechanisms: underlying identified identification new genes pertinent tolerance using innovative methodologies, harnessing CRISPR artificial intelligence modification, introducing plant future directions.

Language: Английский

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A novel variant of the Calvin–Benson cycle bypassing fructose bisphosphate

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: March 16, 2022

The Calvin-Benson cycle (CB cycle) is quantitatively the most important metabolic pathway for CO2 fixation. In canonical CB cycle, fructose 6-phosphate (F6P), 1,6-bisphosphate (FBP), sedoheptulose 7-phosphate (S7P), and 1,7-bisphosphate (SBP) appear as essential intermediates, where F6P formed from FBP by 1,6-bisphosphatase (FBPase) reaction, S7P SBP 1,7-bisphosphatase (SBPase) reaction. Although involvement of SBPase in consistent with reported dependency photosynthetic carbon metabolism on SBPase, FBPase not completely FBP- or FBPase-related findings such as, although a diminished growth rate, an Arabidopsis mutant lacking grew photoautotrophically soil. Here, we show novel variant involving SBP, transaldolase, but neither nor FBPase. This variant, named S7P-removing transaldolase bypasses FBP. explains more easily than well further suggests that co-overexpression can be strategy enhancing metabolism, which global environment.

Language: Английский

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The Calvin Benson cycle in bacteria: New insights from systems biology

Seminars in Cell and Developmental Biology, Journal Year: 2023, Volume and Issue: 155, P. 71 - 83

Published: March 29, 2023

The Calvin Benson cycle in phototrophic and chemolithoautotrophic bacteria has ecological biotechnological importance, which motivated study of its regulation. I review recent advances our understanding how the is regulated technologies used to elucidate regulation modify it, highlight differences between photoautotrophic models. Systems biology studies have shown that oxygenic bacteria, enzymes are extensively at post-transcriptional post-translational levels, with multiple enzyme activities connected cellular redox status through thioredoxin. In primarily transcriptional level, effector metabolites transducing cell status, though new methods should now allow facile, proteome-wide exploration biochemical these A objective enhance CO2 fixation partition carbon a product interest. Flux control distributed over enzymes, attempts modulate gene expression show robust homeostatic growth rate, synthesis rates products can be significantly increased. Therefore, de-regulation protein engineering may necessary increase fluxes. Non-canonical cycles, if implemented synthetic biology, could reduced energy demand loading, thus increasing attractiveness for industrial applications.

Language: Английский

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TurboID reveals the proxiomes of Chlamydomonas proteins involved in thylakoid biogenesis and stress response

PLANT PHYSIOLOGY, Journal Year: 2023, Volume and Issue: 193(3), P. 1772 - 1796

Published: June 13, 2023

Abstract In Chlamydomonas (Chlamydomonas reinhardtii), the VESICLE-INDUCING PROTEIN IN PLASTIDS 1 and 2 (VIPP1 VIPP2) play roles in sensing coping with membrane stress thylakoid biogenesis. To gain more insight into these processes, we aimed to identify proteins interacting VIPP1/2 chloroplast chose proximity labeling (PL) for this purpose. We used transient interaction between nucleotide exchange factor CHLOROPLAST GRPE HOMOLOG (CGE1) stromal HEAT SHOCK 70B (HSP70B) as test system. While PL APEX2 BioID proved be inefficient, TurboID resulted substantial biotinylation vivo. TurboID-mediated baits under ambient H2O2 conditions confirmed known interactions of VIPP1 VIPP2, HSP70B, DNAJ (CDJ2). Proteins identified proxiomes can grouped involved biogenesis complexes regulation photosynthetic electron transport, including PROTON GRADIENT REGULATION 5-LIKE (PGRL1). A third group comprises 11 unknown function whose genes are upregulated conditions. named them VIPP PROXIMITY LABELING (VPL). reciprocal experiments, VPL2 PGRL1. Our results demonstrate robustness studying protein networks pave way analyzing functions VIPPs responses.

Language: Английский

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Targeted metabolite profiling as a top-down approach to uncover interspecies diversity and identify key conserved operational features in the Calvin–Benson cycle

Journal of Experimental Botany, Journal Year: 2021, Volume and Issue: 72(17), P. 5961 - 5986

Published: June 21, 2021

Improving photosynthesis is a promising avenue to increase crop yield. This will be aided by better understanding of natural variance in photosynthesis. Profiling Calvin-Benson cycle (CBC) metabolites provides top-down strategy uncover inter-species diversity CBC operation. In study four C4 and five C3 species, principal components analysis separated species from also different species. These separations were driven that reflect known species-differences their biochemistry pathways. Unexpectedly, there was considerable between the Falling atmospheric CO2 changing temperature, nitrogen water availability have evolution multiple lineages. We propose analogous selective pressures drove lineage-dependent Examples species-dependent variation include differences balance light reactions, regulated steps CBC. Metabolite profiles reveal conserved features including inactivation enzymes low irradiance, maintenance at relatively high levels absence net fixation. may important for photosynthetic efficiency light, fluctuating irradiance when stomata close due availability.

Language: Английский

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