Article
Microbiology
D. Isabel Petrescu, Preston L. Dilbeck, Beronda L. Montgomery
Summary: The orange carotenoid protein (OCP) family of proteins are light-activated proteins that help dissipate excess energy absorbed by accessory light-harvesting complexes in cyanobacteria. Different environmental factors, including light and cellular redox regulation, impact the regulation of OCP homolog genes, indicating potential functional diversity of this gene family in cyanobacteria. The regulation of OCP homologs in response to various environmental cues is complex and involves photoreceptors and transcriptional regulators.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Plant Sciences
Yi-Wen Yang, Ke Liu, Da Huang, Chen Yu, Si-Zhuo Chen, Min Chen, Bao-Sheng Qiu
Summary: Expanded orange carotenoid protein paralogs in subaerial Nostoc species have specialized functions as either singlet oxygen quenchers or phycobilisome fluorescence quenchers for survival in desiccation conditions. The different paralogs displayed different activities, with HCP2 being the most effective singlet oxygen quencher and OCPx1 exhibiting stronger phycobilisome fluorescence quenching compared to OCPx2. The crystal structures and mutant analysis revealed important roles for Trp111 and Met125 in OCPx2, which showed a more flexible regulation in energy quenching activities compared to OCPx1.
Article
Biochemistry & Molecular Biology
Adjele Wilson, Fernando Muzzopappa, Diana Kirilovsky
Summary: The Orange Carotenoid Protein (OCP) is a soluble photoactive protein involved in cyanobacterial photoprotection by interacting with N-terminal and C-terminal domains. The study found that the NTD surface interacting with the CTD in the orange OCP is crucial for binding to PBS. Additionally, amino acid modifications affect OCP photoactivation and recovery rates, indicating involvement in carotenoid translocation.
BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS
(2022)
Article
Multidisciplinary Sciences
Raquel Garcia-Canas, Joaquin Giner-Lamia, Francisco J. Florencio, Luis Lopez-Maury
Summary: The study reveals the involvement of proteins PetR and PetP in regulating the soluble electron carrier in cells. Transcriptomic analysis shows that the PetRP system specifically regulates four genes (petE, petJ, slr0601, and slr0602), with their presence potentially representing an early adaptation to decreased iron bioavailability following the GOE.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Biochemistry & Molecular Biology
Mahmoud Sharawy, Natalia B. Pigni, Eric R. May, Jose A. Gascon
Summary: This study investigates the protein rearrangements of the orange carotenoid protein (OCP) using metadynamics. The results reveal the importance of ketocarotenoid translocation for domain separation and provide an energetically feasible pathway to dissociation.
Article
Biotechnology & Applied Microbiology
Matteo Pivato, Federico Perozeni, Francesco Licausi, Stefano Cazzaniga, Matteo Ballottari
Summary: A synthetic biology approach was successfully used to express a FT OCP2 protein from a thermophilic cyanobacterium in the green algae Chlamydomonas reinhardtii, with robust expression and successful localization into the chloroplast. Different strategies were employed to optimize expression in UV-mediated mutants and strains engineered for constitutive expression of an endogenous carotene ketolase, resulting in astaxanthin and other ketocarotenoids accumulation. Furthermore, the ketocarotenoid-binding FT OCP2 holoproteins maintained their photoconversion properties, suggesting a potential novel tool for improving solubility of ketocarotenoids in green algae.
ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS
(2021)
Article
Biotechnology & Applied Microbiology
Hengkai Meng, Wei Zhang, Huawei Zhu, Fan Yang, Yanping Zhang, Jie Zhou, Yin Li
Summary: This study proposed a novel strategy to enhance cyclic electron transfer to provide sufficient NADH for the photosynthetic production of chemicals by redirecting excess electrons from plastoquinone to photosystem I. Introduction of the OmcS gene into Synechococcus elongatus UTEX 2973 resulted in increased intracellular ATP, NADH concentrations, biomass production, and d-lactate production. Transcriptome analysis revealed upregulation of proteins involved in cyclic electron transfer and downregulation of proteins involved in respiratory electron transfer, contributing to the increased levels of ATP and NADH.
BIOTECHNOLOGY FOR BIOFUELS
(2021)
Article
Biochemistry & Molecular Biology
Yury B. Slonimskiy, Andrei O. Zupnik, Larisa A. Varfolomeeva, Konstantin M. Boyko, Eugene G. Maksimov, Nikolai N. Sluchanko
Summary: Cyanobacteria played a crucial role in the Great Oxygenation Event, and the Gloeobacter OCPX, a primitive form of OCP, exhibits unique functional adaptations and faster recovery after photoactivation through an intramolecular locking mechanism.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2022)
Article
Chemistry, Applied
Silvia Leccese, Thomas Onfroy, Adjele Wilson, Diana Kirilovsky, Sandra Casale, Saremble Guira, Mohamed Selmane, Claude Jolivalt, Alberto Mezzetti
Summary: This study focuses on the immobilization of the photoactive Orange Carotenoid Protein (OCP) on mesoporous silica nanoparticles and investigates its structural characterization. The results highlight the enhanced immobilization of OCP by pre-photoactivation, leading to photochromic nanoparticles. The study also explores the possibility of releasing OCP from the nanoparticles and suggests potential applications in nanoscale optical devices and antioxidant drug delivery.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Biochemistry & Molecular Biology
Nikolai N. Sluchanko, Eugene G. Maksimov, Yury B. Slonimskiy, Larisa A. Varfolomeeva, Antonina Y. Bukhanko, Nikita A. Egorkin, Georgy Tsoraev, Maria G. Khrenova, Baosheng Ge, Song Qin, Konstantin M. Boyko, Vladimir O. Popov
Summary: This study presents the first crystal structures of OCP2 from cyanobacteria with different morphoecophysiological characteristics and provides a comprehensive comparison of their structure, spectroscopy, and function with OCP1, OCP3, and all-OCP ancestor. The structures enable the correlation of spectroscopic signatures with the effective number of hydrogen and the discovery of chalcogen bonds anchoring the ketocarotenoid in OCP, as well as the rotation of the echinenone's beta-ionone ring in the CTD. The structural data also helped rationalize the observed differences in OCP/FRP and OCP/phycobilisome functional interactions.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2024)
Article
Plant Sciences
Christopher Hepworth, William H. J. Wood, Tom Z. Emrich-Mills, Matthew S. Proctor, Stuart Casson, Matthew P. Johnson
Summary: The phosphorylation of LHCII by TAP38/STN7 regulates the excitation rates of PSI and PSII, as well as the size of thylakoid grana stacks. By comparing different plant mutants, it was found that smaller grana enhance PSI reduction and photosynthesis under low light, while larger grana optimize photosynthesis by preventing PSI photoinhibition under high light. State transitions and dynamic thylakoid stacking work synergistically to regulate photosynthesis in variable light conditions.
Review
Biochemistry & Molecular Biology
Chun-Chi Chen, Jian Min, Lilan Zhang, Yu Yang, Xuejing Yu, Rey-Ting Guo
Summary: Cytochrome P450s are crucial enzymes involved in biological metabolism and have great potential in biotechnological applications due to their ability to catalyze various reactions with a wide range of organic compounds. Understanding the electron transfer pathway of P450s is essential for enhancing our knowledge of these enzymes and improving their efficiency.
Article
Biochemistry & Molecular Biology
Man-Hyuk Han, Hee Wook Yang, Jungmin Yoon, Yvette Villafani, Ji-Young Song, Cheol Ho Pan, Keunwan Park, Youngmoon Cho, Ji-Joon Song, Seung Joong Kim, Youn-Il Park, Jiyong Park
Summary: This study investigates a mutation in the OCP protein of Gloeocapsa sp. PCC 7513, which results in red- or blue-shifts in the absorption maxima. The analysis reveals that the mutation alters the polar environment around the bound chromophore, affecting the charge transfer in the photoexcited state. These findings provide insights into the color-specific photoswitch design.
MOLECULES AND CELLS
(2023)
Article
Plant Sciences
Jakob-Maximilian Keller, Maureen Julia Frieboes, Ludwig Joedecke, Sandrine Kappel, Natalia Wulff, Tobias Rindfleisch, Omar Sandoval-Ibanez, Ines Gerlach, Wolfram Thiele, Ralph Bock, Juergen Eirich, Iris Finkemeier, Danja Schuenemann, Reimo Zoschke, Mark Aurel Schoettler, Ute Armbruster
Summary: This study demonstrates the role of the DECREASED ELECTRON TRANSPORT AT PSII (DEAP2) assembly factor in the early assembly of photosystem II (PSII) in plants. It shows that DEAP2 works together with the PHOTOSYNTHESIS AFFECTED MUTANT 68 (PAM68) factor to facilitate the formation of the RC47 intermediate. The loss of both DEAP2 and PAM68 leads to a loss of functional PSII and the inability of plants to grow photoautotrophically.
Article
Microbiology
Ming-Hua Liang, Shan-Rong Xie, Jv-Liang Dai, Hao-Hong Chen, Jian-Guo Jiang
Summary: Phytoene synthase (PSY) is a key enzyme in carotenoid metabolism, and DsPSY1 dominates carotenogenesis in Dunaliella salina, while DsPSY2 has little activity. The interaction between DsOR and DsPSY1/2 promotes carotenoid accumulation and regulates plastid development.
MICROBIOLOGY SPECTRUM
(2023)
