Lighting the way: Compelling open questions in photosynthesis research

The Plant Cell, Journal Year: 2024, Volume and Issue: 36(10), P. 3914 - 3943

Published: July 22, 2024

Abstract Photosynthesis—the conversion of energy from sunlight into chemical energy—is essential for life on Earth. Yet there is much we do not understand about photosynthetic a fundamental level: how it evolved and the extent its diversity, dynamics, all components connections involved in regulation. In this commentary, researchers working aspects photosynthesis including light-dependent reactions, photorespiration, C4 metabolism pose discuss what they view as most compelling open questions their areas research.

Language: Английский

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Structure, biogenesis, and evolution of thylakoid membranes

The Plant Cell, Journal Year: 2024, Volume and Issue: 36(10), P. 4014 - 4035

Published: April 3, 2024

Cyanobacteria and chloroplasts of algae plants harbor specialized thylakoid membranes (TMs) that convert sunlight into chemical energy. These house PSII I, the vital protein-pigment complexes drive oxygenic photosynthesis. In course their evolution, TMs have diversified in structure. However, core machinery for photosynthetic electron transport remained largely unchanged, with adaptations occurring primarily light-harvesting antenna systems. Whereas cyanobacteria are relatively simple, they become more complex plants. The vascular contain intricate networks stacked grana unstacked stroma thylakoids. This review provides an in-depth view TM architectures phototrophs determinants shape forms, as well presenting recent insights spatial organization biogenesis maintenance. Its overall goal is to define underlying principles guided evolution these bioenergetic membranes.

Language: Английский

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Structure of a unique PSII-Pcb tetrameric megacomplex in a chlorophyll d –containing cyanobacterium

Science Advances, Journal Year: 2024, Volume and Issue: 10(8)

Published: Feb. 23, 2024

Acaryochloris marina is a unique cyanobacterium using chlorophyll d (Chl ) as its major pigment and thus can use far-red light for photosynthesis. Photosystem II (PSII) of A. associates with number prochlorophyte Chl-binding (Pcb) proteins to act the light-harvesting system. We report here cryo-electron microscopic structure PSII-Pcb megacomplex from at 3.6-angstrom overall resolution 3.3-angstrom local resolution. The organized tetramer consisting two PSII core dimers flanked by sixteen symmetrically related Pcb proteins, total molecular weight 1.9 megadaltons. reveals detailed organization 15 known protein subunits an unknown subunit, assembly 4 antennas within each monomer, possible pathways energy transfer megacomplex, providing deep insights into dissipation mechanisms involved in utilization.

Language: Английский

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Transcriptomic and photosynthetic analyses of Synechocystis sp. PCC6803 and Chlorogloeopsis fritschii sp. PCC6912 exposed to an M-dwarf spectrum under an anoxic atmosphere

Frontiers in Plant Science, Journal Year: 2024, Volume and Issue: 14

Published: Jan. 18, 2024

Introduction Cyanobacteria appeared in the anoxic Archean Earth, evolving for first time oxygenic photosynthesis and deeply changing atmosphere by introducing oxygen. Starting possibly from UV-protected environments, characterized low visible far-red enriched light spectra, cyanobacteria spread everywhere on Earth thanks to their adaptation capabilities harvesting. In last decade, few species which can acclimate through Far-Red Light Photoacclimation (FaRLiP) have been isolated. FaRLiP were thus proposed as model organisms study origin of well its possible functionality around stars with high emission, M-dwarfs. These are astrobiological targets, longevity could sustain life evolution they demonstrated host rocky terrestrial-like exoplanets within Habitable Zone. Methods We studied acclimation responses strain Chlorogloeopsis fritschii sp. PCC6912 non-FaRLiP Synechocystis PCC6803 combination three simulated spectra (M-dwarf, solar far-red) two atmospheric compositions (oxic, anoxic). checked growth, O 2 production pigment composition, then we transcriptional RNA sequencing under each spectrum conditions. Results discussion did not show relevant differences gene expression when comparing M-dwarf solar-simulated lights, while caused a variation level many genes. showed, contrary, different condition activated response light. Surprisingly, impact profile strains significantly. that both seem inherently prepared anoxia harvest photons emitted star, whether only (PCC6803) or also (PCC6912). They sufficient keep similar metabolism respect Conclusion prove adaptability cyanobacterial enhance plausibility finding biospheres orbiting stars.

Language: Английский

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Reconstructing Early Microbial Life

Annual Review of Microbiology, Journal Year: 2024, Volume and Issue: 78(1), P. 463 - 492

Published: Aug. 21, 2024

For more than 3.5 billion years, life experienced dramatic environmental extremes on Earth. These include shifts from oxygen-less to overoxygenated atmospheres and cycling between hothouse conditions global glaciations. Meanwhile, an ecological revolution took place. Earth evolved one dominated by microbial containing the plants animals that are most familiar today. Many key cellular features early in history of life, collectively defining nature our biosphere underpinning human survival. Recent advances molecular biology bioinformatics have greatly improved understanding evolution across deep time. However, incorporation genetics, population biology, evolutionary approaches into study Precambrian biota remains a significant challenge. This review synthesizes current knowledge with emphasis ancient metabolisms. It also outlines foundations emerging interdisciplinary area integrates microbiology, paleobiology, synthetic reconstruct biological innovations.

Language: Английский

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Occupancy Analysis of Water Molecules inside Channels within 25 Å Radius of the Oxygen-Evolving Center of Photosystem II in Molecular Dynamics Simulations

The Journal of Physical Chemistry B, Journal Year: 2024, Volume and Issue: 128(10), P. 2236 - 2248

Published: Feb. 20, 2024

At room temperature and neutral pH, the oxygen-evolving center (OEC) of photosystem II (PSII) catalyzes water oxidation. During this process, oxygen is released from OEC, while substrate waters are delivered to OEC protons passed lumen through channels known as narrow or O4 channel, broad Cl1 large O1 channel. Protein residues lining surfaces these play a critical role in stabilizing hydrogen-bonding networks that assist process. We carried out an occupancy analysis better understand structural possible dynamics full PSII monomer molecular (MD) trajectories both S1 S2 states. find equilibrated positions molecules derived MD-derived electron density maps largely match experimentally observed crystallography. Furthermore, reduction MD simulations some inside single-filed channel also correlates well with crystallographic data during transition when state advances state. The overall reduced occupancies source their "vacancy-hopping" dynamic nature channels, unlike ice lattice where all have fixed unit occupancy. propose on basis findings our molecule occupying pocket formed by D1-D61, D1-S169, could be last steppingstone enter into may favored for proton transfer.

Language: Английский

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Water Ligands Regulate the Redox Leveling Mechanism of the Oxygen-Evolving Complex of the Photosystem II

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(23), P. 15986 - 15999

Published: June 4, 2024

Understanding how water ligands regulate the conformational changes and functionality of oxygen-evolving complex (OEC) in photosystem II (PSII) throughout catalytic cycle oxygen evolution remains a highly intriguing unresolved challenge. In this study, we investigate effect insertion (WI) on redox state OEC by using molecular dynamics (MD) quantum mechanics/molecular mechanics (QM/MM) hybrid methods. We find that binding significantly reduces free energy change for proton-coupled electron transfer (PCET) from Mn to Y

Language: Английский

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Biomedical engineering utilizing living photosynthetic cyanobacteria and microalgae: Current status and future prospects

Materials Today Bio, Journal Year: 2024, Volume and Issue: 27, P. 101154 - 101154

Published: July 14, 2024

Cyanobacteria are the only prokaryotes capable of performing oxygenic photosynthesis on Earth. Besides their traditional roles serving as primary producers, cyanobacteria also synthesize abundant secondary metabolites including carotenoids, alkaloids, peptides, which have been reported to possess medicinal potentials. More importantly, advancement synthetic biology technology has further expanded potential biomedical applications especially using living/engineered cyanobacteria, providing promising and attractive strategies for future disease treatments. To improve understanding facilitate applications, this review aims discuss current status prospects cyanobacterial-based engineering. Firstly, specific properties related with like natural products bioactive compounds heavy metal adsorption were concluded. Subsequently, based these we discussed progress in various models hypoxia microenvironment alleviation, wound healing, drug delivery, so on. Finally, exploration metabolites, integration synthesized by situ medical diagnosis treatment, optimization vivo application critically presented. The will promote studies cyanobacteria-based engineering its practical clinical trials future.

Language: Английский

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The optimized Maxent model reveals the pattern of distribution and changes in the suitable cultivation areas for Reaumuria songarica being driven by climate change

Ecology and Evolution, Journal Year: 2024, Volume and Issue: 14(7)

Published: July 1, 2024

Abstract Reaumuria songarica , a drought‐resistant shrub, is widely distributed and plays crucial role in the northern deserts of China. It key species for desert rehabilitation afforestation efforts. Using Maxent model to predict suitable planting areas R. an important strategy combating desertification. With 184 occurrence points 13 environmental variables, optimized has identified main limiting factors its distribution. Distribution patterns variation trends were projected current future climates (2030s, 2050s, 2070s, 2090s) different scenarios (ssp_126, ssp_370, ssp_585). Results show that setting parameters RM (regulation multiplier) = 4 FC (feature combination) LQHPT yields with good accuracy high reliability. Currently, primarily control eight provinces autonomous regions, including Inner Mongolia, Xinjiang, Qinghai, Ningxia. The total area 148.80 × 10 km 2 representing 15.45% China's land area. Precipitation (Precipitation wettest month, warmest quarter, Annual precipitation) Ultraviolet‐B seasonality are primary growth distribution . Mean temperature quarter factor driving changes under climate scenarios. In scenarios, will shrink, center shift towards higher latitude, potentially indicate further highly habitat increased, while moderately less have decreased. Increased precipitation within 's water tolerance range favorable reproduction. cultivation priority should be given exploring utilizing germplasm resources. Introduction can conducted expanding scientifically effective measures implemented protect resources contracting regions. findings this study provide theoretical basis addressing desertification resulting from change offer practical insights development, utilization, introduction,

Language: Английский

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Photosynthetic Bacteria: Light-Responsive Biomaterials for Anti-Tumor Photodynamic Therapy

International Journal of Nanomedicine, Journal Year: 2025, Volume and Issue: Volume 20, P. 465 - 482

Published: Jan. 1, 2025

Abstract: Photodynamic therapy (PDT) is a promising noninvasive tumor treatment modality that relies on generating reactive oxygen species (ROS) and requires an adequate supply to the target tissue. However, hypoxia common feature of solid tumors profoundly restricts anti-tumor efficacy PDT. In recent years, scholars have focused exploring nanomaterial-based strategies for supplementation integrating non-oxygen-consuming approaches overcome hypoxic limitations Some harnessed photosynthetic production cyanobacteria under light irradiation engineered them as carriers photosensitizers instead inorganic nanomaterials, resulting in bacteria (PSB) attracting significant attention. Recent studies shown light-triggered PSB can exhibit additional properties, such hydrogen production, ROS generation, photothermal conversion, facilitating their use light-responsive biomaterials enhancing Therefore, understanding provide new insights ideas future research. This review mainly introduces characteristics research PDT enrich our knowledge this area. Finally, challenges prospects using enhance were also discussed. Keywords: bacteria, PDT, hypoxia, cyanobacteria, purple PTT

Language: Английский

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