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Yanykin D, Paskhin M, Ashikhmin AA, Bolshakov MA. Carotenoid-dependent singlet oxygen photogeneration in light-harvesting complex 2 of Ectothiorhodospira haloalkaliphila leads to the formation of organic hydroperoxides and damage to both pigments and protein matrix. PeerJ 2024; 12:e16615. [PMID: 38250719 PMCID: PMC10798160 DOI: 10.7717/peerj.16615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 11/15/2023] [Indexed: 01/23/2024] Open
Abstract
Earlier, it was suggested that carotenoids in light-harvesting complexes 2 (LH2) can generate singlet oxygen, further oxidizing bacteriochlorophyll to 3-acetyl-chlorophyll. In the present work, it was found that illumination of isolated LH2 preparations of purple sulfur bacterium Ectothiorhodospira haloalkaliphila with light in the carotenoid absorption region leads to the photoconsumption of molecular oxygen, which is accompanied by the formation of hydroperoxides of organic molecules in the complexes. Photoformation of two types of organic hydroperoxides were revealed: highly lipophilic (12 molecules per one LH2) and relatively hydrophobic (68 per one LH2). It has been shown that illumination leads to damage to light-harvesting complexes. On the one hand, photobleaching of bacteriochlorophyll and a decrease in its fluorescence intensity are observed. On the other hand, the photoinduced increase in the hydrodynamic radius of the complexes, the reduction in their thermal stability, and the change in fluorescence intensity indicate conformational changes occurring in the protein molecules of the LH2 preparations. Inhibition of the processes described above upon the addition of singlet oxygen quenchers (L-histidine, Trolox, sodium L-ascorbate) may support the hypothesis that carotenoids in LH2 preparations are capable of generating singlet oxygen, which, in turn, damage to protein molecules.
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Affiliation(s)
- Denis Yanykin
- Institute of Basic Biological Problems, FRC PSCBR, Pushchino, Moscow, Russia
- Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow, Moscow, Russia
| | - Mark Paskhin
- Institute of Basic Biological Problems, FRC PSCBR, Pushchino, Moscow, Russia
- Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow, Moscow, Russia
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2
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Xing SF, Tian HF, Yan Z, Song C, Wang SG. Stability and biomineralization of cadmium sulfide nanoparticles biosynthesized by the bacterium Rhodopseudomonas palustris under light. JOURNAL OF HAZARDOUS MATERIALS 2023; 458:131937. [PMID: 37421856 DOI: 10.1016/j.jhazmat.2023.131937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/08/2023] [Accepted: 06/23/2023] [Indexed: 07/10/2023]
Abstract
Cadmium (Cd) pollution is regarded as a potent problem due to its hazard risks to the environment, making it crucial to be removed. Compared to the physicochemical techniques (e.g., adsorption, ion exchange, etc.), bioremediation is a promising alternative technology for Cd removal, due to its cost-effectiveness, and eco-friendliness. Among them, microbial-induced cadmium sulfide mineralization (Bio-CdS NPs) is a process of great significance for environmental protection. In this study, microbial cysteine desulfhydrase coupled with cysteine acted as a strategy for Bio-CdS NPs by Rhodopseudomonas palustris. The synthesis, activity, and stability of Bio-CdS NPs-R. palustris hybrid was explored under different light conditions. Results show that low light (LL) intensity could promote cysteine desulfhydrase activities to accelerate hybrid synthesis, and facilitated bacterial growth by the photo-induced electrons of Bio-CdS NPs. Additionally, the enhanced cysteine desulfhydrase activity effectively alleviated high Cd-stress. However, the hybrid rapidly dissolved under changed environmental factors, including light intensity and oxygen. The factors affecting the dissolution were ranked as follows: darkness/microaerobic ≈ darkness/aerobic < LL/microaerobic < high light (HL)/microaerobic < LL/aerobic < HL/aerobic. The research provides a deeper understanding of Bio-CdS NPs-bacteria hybird synthesis and its stability in Cd-polluted water, allowing advanced bioremediation treatment of heavy metal pollution in water.
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Affiliation(s)
- Su-Fang Xing
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Hui-Fang Tian
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Zhen Yan
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Chao Song
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Shu-Guang Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; Sino-French Research Institute for Ecology and Environment (ISFREE), School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; Weihai Research Institute of Industrial Technology, Shandong University, Weihai 264209, China.
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3
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Chiarelli-Neto O, Garcez ML, Pavani C, Martins W, de Abreu Quintela Castro FC, Ambrosio RP, Meotti FC, Baptista MS. Inflammatory stimulus worsens the effects of UV-A exposure on J774 cells. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2023; 239:112647. [PMID: 36634432 DOI: 10.1016/j.jphotobiol.2023.112647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 12/18/2022] [Accepted: 01/01/2023] [Indexed: 01/06/2023]
Abstract
UV-A radiation affects skin homeostasis by promoting oxidative distress. Endogenous photosensitizers in the dermis and epidermis of human skin absorb UV-A radiation forming excited states (singlet and triplet) and reactive oxygen species (ROS) producing oxidized compounds that trigger biological responses. The activation of NF-kB induces the expression of pro-inflammatory cytokines and can intensify the generation of ROS. However, there is no studies evaluating the cross talks between inflammatory stimulus and UV-A exposure on the levels of redox misbalance and inflammation. In here, we evaluated the effects of UV-A exposure on J774 macrophage cells previously challenged with LPS in terms of oxidative distress, release of pro-inflammatory cytokines, and activation of regulated cell death pathways. Our results showed that LPS potentiates the dose-dependent UV-A-induced oxidative distress and cytokine release, in addition to amplifying the regulated (autophagy and apoptosis) and non-regulated (necrosis) mechanisms of cell death, indicating that a previous inflammatory stimulus potentiates UV-A-induced cell damage. We discuss these results in terms of the current-available skin care strategies.
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Affiliation(s)
- Orlando Chiarelli-Neto
- Departamento de Bioquimica, Instituto de Química IQUSP, Universidade de São Paulo, Brazil; Centro Universitário do Espírito Santo-UNESC, Brazil
| | | | - Christiane Pavani
- Biophotonics Applied to Health Sciences, Uninove, São Paulo, SP, Brazil
| | - Waleska Martins
- Universidade Anhanguera de São Paulo, Stricto-sensu, Kroton, Brazil
| | | | | | - Flavia Carla Meotti
- Departamento de Bioquimica, Instituto de Química IQUSP, Universidade de São Paulo, Brazil
| | - Mauricio S Baptista
- Departamento de Bioquimica, Instituto de Química IQUSP, Universidade de São Paulo, Brazil.
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4
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Baptista MS, Cadet J, Greer A, Thomas AH. Practical Aspects in the Study of Biological Photosensitization Including Reaction Mechanisms and Product Analyses: A Do's and Don'ts Guide †. Photochem Photobiol 2022; 99:313-334. [PMID: 36575651 DOI: 10.1111/php.13774] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 12/24/2022] [Indexed: 12/29/2022]
Abstract
The interaction of light with natural matter leads to a plethora of photosensitized reactions. These reactions cause the degradation of biomolecules, such as DNA, lipids, proteins, being therefore detrimental to the living organisms, or they can also be beneficial by allowing the treatment of several diseases by photomedicine. Based on the molecular mechanistic understanding of the photosensitization reactions, we propose to classify them in four processes: oxygen-dependent (type I and type II processes) and oxygen-independent [triplet-triplet energy transfer (TTET) and photoadduct formation]. In here, these processes are discussed by considering a wide variety of approaches including time-resolved and steady-state techniques, together with solvent, quencher, and scavenger effects. The main aim of this survey is to provide a description of general techniques and approaches that can be used to investigate photosensitization reactions of biomolecules together with basic recommendations on good practices. Illustration of the suitability of these approaches is provided by the measurement of key biomarkers of singlet oxygen and one-electron oxidation reactions in both isolated and cellular DNA. Our work is an educational review that is mostly addressed to students and beginners.
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Affiliation(s)
- Maurício S Baptista
- Department of Biochemistry, Institute of Chemistry, Universidade de São Paulo, São Paulo, Brazil
| | - Jean Cadet
- Département de Médecine Nucléaire et de Radiobiologie, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Alexander Greer
- Department of Chemistry, Brooklyn College, Brooklyn, New York, USA.,Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, New York, USA
| | - Andrés H Thomas
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP), CCT La Plata-CONICET, La Plata, Argentina
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5
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Makhneva ZK, Moskalenko AA. Carotenoids in LH2 Complexes from Allochromatium vinosum under Illumination Are Able to Generate Singlet Oxygen Which Oxidizes BChl850. Microbiology (Reading) 2022. [DOI: 10.1134/s002626172230021x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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6
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Haussmann PB, Pavani C, Marcolongo-Pereira C, Bellettini-Santos T, da Silva BS, Benedito IF, Freitas ML, Baptista MS, Chiarelli-Neto O. Melanin photosensitization by green light reduces melanoma tumor size. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY 2022. [DOI: 10.1016/j.jpap.2021.100092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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7
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Modulation of Antioxidant Activity Enhances Photoautotrophic Cell Growth of Rhodobacter sphaeroides in Microbial Electrosynthesis. ENERGIES 2022. [DOI: 10.3390/en15030935] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Global warming is currently accelerating due to an increase in greenhouse gas emissions by industrialization. Microbial electrosynthesis (MES) using electroactive autotrophic microorganisms has recently been reported as a method to reduce carbon dioxide, the main culprit of greenhouse gas. However, there are still few cases of application of MES, and the molecular mechanisms are largely unknown. To investigate the growth characteristics in MES, we carried out growth tests according to reducing power sources in Rhodobacter sphaeroides. The growth rate was significantly lower when electrons were directly supplied to cells, compared to when hydrogen was supplied. Through a transcriptome analysis, we found that the expression of reactive oxygen species (ROS)-related genes was meaningfully higher in MES than in normal photoautotrophic conditions. Similarly, endogenous contents of H2O2 were higher and peroxidase activities were lower in MES. The exogenous application of ascorbic acid, a representative biological antioxidant, promotes cell growth by decreasing ROS levels, confirming the inhibitory effects of ROS on MES. Taken together, our observations suggest that reduction of ROS by increasing antioxidant activities is important for enhancing the cell growth and production of CO2-converting substances such as carotenoids in MES in R. sphaeroides
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8
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Melanin, lipofuscin and the effects of visible light in the skin. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY 2021. [DOI: 10.1016/j.jpap.2021.100044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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9
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Makhneva ZK, Bolshakov MA, Moskalenko AA. Carotenoids Do Not Protect Bacteriochlorophylls in Isolated Light-Harvesting LH2 Complexes of Photosynthetic Bacteria from Destructive Interactions with Singlet Oxygen. Molecules 2021; 26:5120. [PMID: 34500552 PMCID: PMC8434301 DOI: 10.3390/molecules26175120] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 08/18/2021] [Accepted: 08/20/2021] [Indexed: 11/22/2022] Open
Abstract
The effect of singlet oxygen on light-harvesting (LH) complexes has been studied for a number of sulfur (S+) and nonsulfur (S-) photosynthetic bacteria. The visible/near-IR absorption spectra of the standard LH2 complexes (B800-850) of Allochromatium (Alc.) vinosum (S+), Rhodobacter (Rba.) sphaeroides (S-), Rhodoblastus (Rbl.) acidophilus (S-), and Rhodopseudomonas (Rps.) palustris (S-), two types LH2/LH3 (B800-850 and B800-830) of Thiorhodospira (T.) sibirica (S+), and an unusual LH2 complex (B800-827) of Marichromatium (Mch.) purpuratum (S+) or the LH1 complex from Rhodospirillum (Rsp.) rubrum (S-) were measured in aqueous buffer suspensions in the presence of singlet oxygen generated by the illumination of the dye Rose Bengal (RB). The content of carotenoids in the samples was determined using HPLC analysis. The LH2 complex of Alc. vinosum and T. sibirica with a reduced content of carotenoids was obtained from cells grown in the presence of diphenylamine (DPA), and LH complexes were obtained from the carotenoidless mutant of Rba. sphaeroides R26.1 and Rps. rubrum G9. We found that LH2 complexes containing a complete set of carotenoids were quite resistant to the destructive action of singlet oxygen in the case of Rba. sphaeroides and Mch. purpuratum. Complexes of other bacteria were much less stable, which can be judged by a strong irreversible decrease in the bacteriochlorophyll (BChl) absorption bands (at 850 or 830 nm, respectively) for sulfur bacteria and absorption bands (at 850 and 800 nm) for nonsulfur bacteria. Simultaneously, we observe the appearance of the oxidized product 3-acetyl-chlorophyll (AcChl) absorbing near 700 nm. Moreover, a decrease in the amount of carotenoids enhanced the spectral stability to the action of singlet oxygen of the LH2 and LH3 complexes from sulfur bacteria and kept it at the same level as in the control samples for carotenoidless mutants of nonsulfur bacteria. These results are discussed in terms of the current hypothesis on the protective functions of carotenoids in bacterial photosynthesis. We suggest that the ability of carotenoids to quench singlet oxygen (well-established in vitro) is not well realized in photosynthetic bacteria. We compared the oxidation of BChl850 in LH2 complexes of sulfur bacteria under the action of singlet oxygen (in the presence of 50 μM RB) or blue light absorbed by carotenoids. These processes are very similar: {[BChl + (RB or carotenoid) + light] + O2} → AcChl. We speculate that carotenoids are capable of generating singlet oxygen when illuminated. The mechanism of this process is not yet clear.
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Affiliation(s)
| | | | - Andrey A. Moskalenko
- Institute of Basic Biological Problems RAS, 142290 Pushchino, Russia; (Z.K.M.); (M.A.B.)
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10
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How does the skin sense sun light? An integrative view of light sensing molecules. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2021. [DOI: 10.1016/j.jphotochemrev.2021.100403] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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11
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Molecular Profiling and Optimization Studies for Growth and PHB Production Conditions in Rhodobacter sphaeroides. ENERGIES 2020. [DOI: 10.3390/en13236471] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
In the recent climate change regime, industrial demand for renewable materials to replace petroleum-derived polymers continues to rise. Of particular interest is polyhydroxybutyrate (PHB) as a substitute for polypropylene. Accumulating evidence indicates that PHB is highly produced as a carbon storage material in various microorganisms. The effects of growth conditions on PHB production have been widely studied in chemolithotrophs, particularly in Rhodobacter. However, the results on PHB production in Rhodobacter have been somewhat inconsistent due to different strains and experimental conditions, and it is currently unclear how diverse environmental factors are linked with PHB production. Here, we report optimized growth conditions for PHB production and show that the growth conditions are closely related to reactive oxygen species (ROS) regulation. PHB accumulates in cells up to approximately 50% at the highest level under dark-aerobic conditions as opposed to light aerobic/anaerobic conditions. According to the time-course, PHB contents increased at 48 h and then gradually decreased. When observing the effect of temperature and medium composition on PHB production, 30 °C and a carbon/nitrogen ratio of 9:1 or more were found to be most effective. Among PHB biosynthetic genes, PhaA and PhaB are highly correlated with PHB production, whereas PhaC and PhaZ showed little change in overall expression levels. We found that, while the amount of hydrogen peroxide in cells under dark conditions was relatively low compared to the light conditions, peroxidase activities and expression levels of antioxidant-related genes were high. These observations suggest optimal culture conditions for growth and PHB production and the importance of ROS-scavenging signaling with regard to PHB production.
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12
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Tonolli PN, Martins WK, Junqueira HC, Silva MN, Severino D, Santacruz-Perez C, Watanabe I, Baptista MS. Lipofuscin in keratinocytes: Production, properties, and consequences of the photosensitization with visible light. Free Radic Biol Med 2020; 160:277-292. [PMID: 32810634 DOI: 10.1016/j.freeradbiomed.2020.08.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 07/03/2020] [Accepted: 08/01/2020] [Indexed: 12/15/2022]
Abstract
A dysfunction in the mitochondrial-lysosomal axis of cellular homeostasis is proposed to cause cells to age quicker and to accumulate lipofuscin. Typical protocols to mediate lipofuscinogenesis are based on the induction of the senescent phenotype either by allowing many consecutive cycles of cell division or by treating cells with physical/chemical agents such as ultraviolet (UV) light or hydrogen peroxide. Due to a direct connection with the physiopathology of age-related macular degeneration, lipofuscin that accumulates in retinal pigment epithelium (RPE) cells have been extensively studied, and the photochemical properties of RPE lipofuscin are considered as standard for this pigment. Yet, many other tissues such as the brain and the skin may prompt lipofuscinogenesis, and the properties of lipofuscin granules accumulated in these tissues are not necessarily the same as those of RPE lipofuscin. Here, we present a light-induced protocol that accelerates cell aging as judged by the maximization of lipofuscinogenesis. Photosensitization of cells previously incubated with nanomolar concentrations of 1,9-dimethyl methylene blue (DMMB), severely and specifically damages mitochondria and lysosomes, leading to a lipofuscin-related senescent phenotype. By applying this protocol in human immortalized non-malignant keratinocytes (HaCaT) cells, we observed a 2.5-fold higher level of lipofuscin accumulation compared to the level of lipofuscin accumulation in cells treated with a typical UV protocol. Lipofuscin accumulated in keratinocytes exhibited the typical red light emission, with excitation maximum in the blue wavelength region (~450 nm). Fluorescence lifetime image microscopy data showed that the keratinocyte lipofuscin has an emission lifetime of ~1.7 ns. Lipofuscin-loaded cells (but not control cells) generated a substantial amount of singlet oxygen (1O2) when irradiated with blue light (420 nm), but there was no 1O2 generation when excitation was performed with a green light (532 nm). These characteristics were compared with those of RPE cells, considering that keratinocyte lipofuscin lacks the bisretinoids derivatives present in RPE lipofuscin. Additionally, we showed that lipofuscin-loaded keratinocytes irradiated with visible light presented critical DNA damages, such as double-strand breaks and Fpg-sensitive sites. We propose that the DMMB protocol is an efficient way to disturb the mitochondrial-lysosomal axis of cellular homeostasis, and consequently, it can be used to accelerate aging and to induce lipofuscinogenesis. We also discuss the consequences of the lipofuscin-induced genotoxicity of visible light in keratinocytes.
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Affiliation(s)
- Paulo N Tonolli
- Universidade de São Paulo, Instituto de Quimica, Departamento de Bioquímica, São Paulo, SP, Brazil
| | - Waleska K Martins
- Universidade de São Paulo, Instituto de Quimica, Departamento de Bioquímica, São Paulo, SP, Brazil; Universidade Anhanguera de São Paulo (UNIAN-SP), São Paulo, SP, Brazil
| | - Helena C Junqueira
- Universidade de São Paulo, Instituto de Quimica, Departamento de Bioquímica, São Paulo, SP, Brazil
| | - Maryana N Silva
- Universidade Anhanguera de São Paulo (UNIAN-SP), São Paulo, SP, Brazil
| | - Divinomar Severino
- Universidade de São Paulo, Instituto de Quimica, Departamento de Bioquímica, São Paulo, SP, Brazil
| | - Carolina Santacruz-Perez
- Universidade de São Paulo, Instituto de Quimica, Departamento de Bioquímica, São Paulo, SP, Brazil
| | - I Watanabe
- Universidade de São Paulo, Instituto de Ciências Biométicas, São Paulo, SP, Brazil
| | - Mauricio S Baptista
- Universidade de São Paulo, Instituto de Quimica, Departamento de Bioquímica, São Paulo, SP, Brazil.
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13
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Tsubone TM, Martins WK, Franco MSF, Silva MN, Itri R, Baptista MS. Cellular compartments challenged by membrane photo-oxidation. Arch Biochem Biophys 2020; 697:108665. [PMID: 33159891 DOI: 10.1016/j.abb.2020.108665] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/20/2020] [Accepted: 10/31/2020] [Indexed: 12/18/2022]
Abstract
The lipid composition impacts directly on the structure and function of the cytoplasmic as well as organelle membranes. Depending on the type of membrane, specific lipids are required to accommodate, intercalate, or pack membrane proteins to the proper functioning of the cells/organelles. Rather than being only a physical barrier that separates the inner from the outer spaces, membranes are responsible for many biochemical events such as cell-to-cell communication, protein-lipid interaction, intracellular signaling, and energy storage. Photochemical reactions occur naturally in many biological membranes and are responsible for diverse processes such as photosynthesis and vision/phototaxis. However, excessive exposure to light in the presence of absorbing molecules produces excited states and other oxidant species that may cause cell aging/death, mutations and innumerable diseases including cancer. At the same time, targeting key compartments of diseased cells with light can be a promising strategy to treat many diseases in a clinical procedure called Photodynamic Therapy. Here we analyze the relationships between membrane alterations induced by photo-oxidation and the biochemical responses in mammalian cells. We specifically address the impact of photosensitization reactions in membranes of different organelles such as mitochondria, lysosome, endoplasmic reticulum, and plasma membrane, and the subsequent responses of eukaryotic cells.
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Affiliation(s)
| | | | - Marcia S F Franco
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, SP, Brazil
| | | | - Rosangela Itri
- Department of Applied Physics, Institute of Physics, University of São Paulo, SP, Brazil
| | - Mauricio S Baptista
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, SP, Brazil.
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14
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Zhang D, Xu J, Bao M, Yan D, Beer S, Beardall J, Gao K. Elevated CO 2 concentration alleviates UVR-induced inhibition of photosynthetic light reactions and growth in an intertidal red macroalga. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2020; 213:112074. [PMID: 33152637 DOI: 10.1016/j.jphotobiol.2020.112074] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 10/19/2020] [Accepted: 10/26/2020] [Indexed: 02/06/2023]
Abstract
The commercially important red macroalga Pyropia (formerly Porphyra) yezoensis is, in its natural intertidal environment, subjected to high levels of both photosynthetically active and ultraviolet radiation (PAR and UVR, respectively). In the present work, we investigated the effects of a plausibly increased global CO2 concentration on quantum yields of photosystems II (PSII) and I (PSI), as well as photosynthetic and growth rates of P. yezoensis grown under natural solar irradiance regimes with or without the presence of UV-A and/or UV-B. Our results showed that the high-CO2 treatment (~1000 μbar, which also caused a drop of 0.3 pH units in the seawater) significantly increased both CO2 assimilation rates (by 35%) and growth (by 18%), as compared with ambient air of ~400 μbar CO2. The inhibition of growth by UV-A (by 26%) was reduced to 15% by high-CO2 concentration, while the inhibition by UV-B remained at ~6% under both CO2 concentrations. Homologous results were also found for the maximal relative photosynthetic electron transport rates (rETRmax), the maximum quantum yield of PSII (Fv/Fm), as well as the midday decrease in effective quantum yield of PSII (YII) and concomitant increased non-photochemical quenching (NPQ). A two-way ANOVA analysis showed an interaction between CO2 concentration and irradiance quality, reflecting that UVR-induced inhibition of both growth and YII were alleviated under the high-CO2 treatment. Contrary to PSII, the effective quantum yield of PSI (YI) showed higher values under high-CO2 condition, and was not significantly affected by the presence of UVR, indicating that it was well protected from this radiation. Both the elevated CO2 concentration and presence of UVR significantly induced UV-absorbing compounds. These results suggest that future increasing CO2 conditions will be beneficial for photosynthesis and growth of P. yezoensis even if UVR should remain at high levels.
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Affiliation(s)
- Di Zhang
- State Key Laboratory of Marine Environmental Science & College of Ocean and Earth Sciences, Xiamen University, Xiamen 361105, China
| | - Juntian Xu
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Menglin Bao
- Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Dong Yan
- State Key Laboratory of Marine Environmental Science & College of Ocean and Earth Sciences, Xiamen University, Xiamen 361105, China
| | - Sven Beer
- Department of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - John Beardall
- State Key Laboratory of Marine Environmental Science & College of Ocean and Earth Sciences, Xiamen University, Xiamen 361105, China; School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
| | - Kunshan Gao
- State Key Laboratory of Marine Environmental Science & College of Ocean and Earth Sciences, Xiamen University, Xiamen 361105, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China.
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15
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Justiniano R, de Faria Lopes L, Perer J, Hua A, Park SL, Jandova J, Baptista MS, Wondrak GT. The Endogenous Tryptophan-derived Photoproduct 6-formylindolo[3,2-b]carbazole (FICZ) is a Nanomolar Photosensitizer that Can be Harnessed for the Photodynamic Elimination of Skin Cancer Cells in Vitro and in Vivo. Photochem Photobiol 2020; 97:180-191. [PMID: 32767762 DOI: 10.1111/php.13321] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 08/03/2020] [Indexed: 01/10/2023]
Abstract
UV-chromophores contained in human skin may act as endogenous sensitizers of photooxidative stress and can be employed therapeutically for the photodynamic elimination of malignant cells. Here, we report that 6-formylindolo[3,2-b]carbazole (FICZ), a tryptophan-derived photoproduct and endogenous aryl hydrocarbon receptor agonist, displays activity as a nanomolar sensitizer of photooxidative stress, causing the photodynamic elimination of human melanoma and nonmelanoma skin cancer cells in vitro and in vivo. FICZ is an efficient UVA/Visible photosensitizer having absorbance maximum at 390 nm (ε = 9180 L mol-1 cm-1 ), and fluorescence and singlet oxygen quantum yields of 0.15 and 0.5, respectively, in methanol. In a panel of cultured human squamous cell carcinoma and melanoma skin cancer cells (SCC-25, HaCaT-ras II-4, A375, G361, LOX), photodynamic induction of cell death was elicited by the combined action of solar simulated UVA (6.6 J cm-2 ) and FICZ (≥10 nm), preceded by the induction of oxidative stress as substantiated by MitoSOX Red fluorescence microscopy, comet detection of Fpg-sensitive oxidative genomic lesions and upregulated stress response gene expression (HMOX1, HSPA1A, HSPA6). In SKH1 "high-risk" mouse skin, an experimental FICZ/UVA photodynamic treatment regimen blocked the progression of UV-induced tumorigenesis suggesting feasibility of harnessing FICZ for the photooxidative elimination of malignant cells in vivo.
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Affiliation(s)
- Rebecca Justiniano
- Department of Pharmacology and Toxicology, College of Pharmacy and UA Cancer Center, University of Arizona, Tucson, AZ, USA
| | - Lohanna de Faria Lopes
- Biochemistry Department, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Jessica Perer
- Department of Pharmacology and Toxicology, College of Pharmacy and UA Cancer Center, University of Arizona, Tucson, AZ, USA
| | - Anh Hua
- Department of Pharmacology and Toxicology, College of Pharmacy and UA Cancer Center, University of Arizona, Tucson, AZ, USA
| | - Sophia L Park
- Department of Pharmacology and Toxicology, College of Pharmacy and UA Cancer Center, University of Arizona, Tucson, AZ, USA
| | - Jana Jandova
- Department of Pharmacology and Toxicology, College of Pharmacy and UA Cancer Center, University of Arizona, Tucson, AZ, USA
| | - Maurício S Baptista
- Biochemistry Department, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Georg T Wondrak
- Department of Pharmacology and Toxicology, College of Pharmacy and UA Cancer Center, University of Arizona, Tucson, AZ, USA
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Makhneva ZK, Ashikhmin AA, Bolshakov MA, Moskalenko AA. Carotenoids are Probably Involved in Singlet Oxygen Generation in the Membranes of Purple Photosynthetic Bacteria under Light Irradiation. Microbiology (Reading) 2020. [DOI: 10.1134/s0026261720010099] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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17
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Makhneva ZK, Ashikhmin AA, Bolshakov MA, Moskalenko AA. Bacteriochlorophyll Interaction with Singlet Oxygen in Membranes of Purple Photosynthetic Bacteria: Does the Protective Function of Carotenoids Exist? DOKL BIOCHEM BIOPHYS 2019; 486:216-219. [PMID: 31367825 DOI: 10.1134/s1607672919030141] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Indexed: 11/23/2022]
Abstract
The direct action of singlet oxygen on the bacteriochlorophyll (BChl) of light-harvesting complexes in the membranes of four species of purple non-sulfur and sulfur photosynthesizing bacteria with and without carotenoids was studied. It was found that BChl in carotenoidless samples is generally more resistant to the action of singlet oxygen compared to the control. It is assumed that carotenoids are not required to protect BChl of bacterial light-harvesting complexes from singlet oxygen, and in the classic work by Griffith et al. [1] the apoptosis process in carotenoidless mutant cells, which involves the destruction of complexes, the appearance of monomeric BChl, and the generation of singlet oxygen caused by BChl, followed by BChl oxidation, was mistakenly attributed to the protective function of carotenoids.
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Affiliation(s)
- Z K Makhneva
- Institute of Basic Biological Problems, Russian Academy of Sciences, 142290, Pushchino, Moscow oblast, Russia
| | - A A Ashikhmin
- Institute of Basic Biological Problems, Russian Academy of Sciences, 142290, Pushchino, Moscow oblast, Russia.
| | - M A Bolshakov
- Institute of Basic Biological Problems, Russian Academy of Sciences, 142290, Pushchino, Moscow oblast, Russia
| | - A A Moskalenko
- Institute of Basic Biological Problems, Russian Academy of Sciences, 142290, Pushchino, Moscow oblast, Russia.
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18
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Abstract
This year marks the 50th anniversary of the discovery of σ70 as a protein factor that was needed for bacterial RNA polymerase to accurately transcribe a promoter in vitro. It was 25 years later that the Group IV alternative σs were described as a distinct family of proteins related to σ70 . In the intervening time, there has been an ever-growing list of Group IV σs, numbers of genes they transcribe, insight into the diverse suite of processes they control, and appreciation for their impact on bacterial lifestyles. This work summarizes knowledge of the Rhodobacter sphaeroides σE -ChrR pair, a member of the ECF11 subfamily of Group IV alternative σs, in protecting cells from the reactive oxygen species, singlet oxygen. It describes lessons learned from analyzing ChrR, a zinc-dependent anti-σ factor, that are generally applicable to Group IV σs and relevant to the response to single oxygen. This MicroReview also illustrates insights into stress responses in this and other bacteria that have been acquired by analyzing or modeling the activity of the σE -ChrR across the bacterial phylogeny.
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Affiliation(s)
- Timothy J. Donohue
- Bacteriology Department, Great Lakes Bioenergy Research CenterWisconsin Energy Institute, University of Wisconsin‐MadisonMadisonWI53726USA
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19
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Makhneva ZK, Ashikhmin AA, Bolshakov MA, Moskalenko AA. Quenchers Protect BChl850 from Action of Singlet Oxygen in the Membranes of a Sulfur Photosynthetic Bacterium Allochromatium vinosum Strain MSU. Microbiology (Reading) 2019. [DOI: 10.1134/s0026261719010119] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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20
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Knox PP, Lukashev EP, Gorokhov VV, Grishanova NP, Paschenko VZ. Hybrid complexes of photosynthetic reaction centers and quantum dots in various matrices: resistance to UV irradiation and heating. PHOTOSYNTHESIS RESEARCH 2019; 139:295-305. [PMID: 29948749 DOI: 10.1007/s11120-018-0529-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 06/05/2018] [Indexed: 06/08/2023]
Abstract
The effects of ultraviolet (UV) irradiation (up to 0.6 J/cm2) and heating (65 °C, 20 min) on the absorption spectra and electron transfer in dehydrated film samples of photosynthetic reaction centers (RCs) from purple bacterium Rhodobacter (Rb.) sphaeroides, as well as in hybrid structures consisting of RCs and quantum dots (QDs), have been studied. The samples were placed in organic matrices containing the stabilizers of protein structure-polyvinyl alcohol (PVA) and trehalose. UV irradiation led to partially irreversible oxidation of some RCs, as well as to transformation of some fraction of the bacteriochlorophyll (BChl) molecules into bacteriopheophytin (BPheo) molecules. In addition, UV irradiation causes degradation of some BChl molecules that is accompanied by formation of 3-acetyl-chlorophyll a molecules. Finally, UV irradiation destroys the RCs carotenoid molecules. The incorporation of RCs into organic matrices reduced pheophytinization. Trehalose was especially efficient in reducing the damage to the carotenoid and BChl molecules caused by UV irradiation. Hybrid films containing RC + QD were more stable to pheophytinization upon UV irradiation. However, the presence of QDs in films did not affect the processes of carotenoid destruction. The efficiency of the electronic excitation energy transfer from QD to P865 also did not change under UV irradiation. Heating led to dramatic destruction of the RCs structure and bacteriochlorins acquired the properties of unbound molecules. Trehalose provided strong protection against destruction of the RCs and hybrid (RC + QD) complexes.
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Affiliation(s)
- Peter P Knox
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Evgeny P Lukashev
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Vladimir V Gorokhov
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Nadezhda P Grishanova
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991
| | - Vladimir Z Paschenko
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, Moscow, Russia, 119991.
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21
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Freitas JV, Junqueira HC, Martins WK, Baptista MS, Gaspar LR. Antioxidant role on the protection of melanocytes against visible light-induced photodamage. Free Radic Biol Med 2019; 131:399-407. [PMID: 30590132 DOI: 10.1016/j.freeradbiomed.2018.12.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 12/22/2018] [Accepted: 12/22/2018] [Indexed: 11/22/2022]
Abstract
Visible light can induce the generation of singlet oxygen and can cause oxidative stress, especially in melanocytes due to melanin photosensitization. Currently, there is no organic UV-filter that provide visible light protection. Previous studies showed that some antioxidants, such as apigenin (API), chrysin (CRI) and beta-carotene (BTC) besides neutralizing radical chain reactions can also quench singlet oxygen via physical or chemical quenching and exhibit potential for use in photoprotection. Therefore, the aim of this study is to evaluate the efficacy of API, CRI and BTC on the protection against cell death induced by melanin photosensitization and understand the underlying mechanisms that are involved in the protection. Precise protocols of melanogenesis and quantification of singlet oxygen generation were developed. Viability of B16-F10 cells with melanin basal levels and after melanogenesis induction was evaluated after visible light exposure in the presence and absence of API, CRI and BTC. Results showed that API and BTC protected cells from photoinduced cell death API exhibiting superior photoprotective effect. We noticed that the efficiency of cell protection and the rate of singlet oxygen suppression are not well correlated, at least for the studied series of antioxidants, indicating that the anti-radical capacity should be playing a major role in protecting cells against the damage induced by melanin photosensitization. In terms of sun care strategies, both API and BTC offer protection against visible light-induced damages and may be effective topical antioxidants to be added to sunscreens.
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Affiliation(s)
- Juliana Vescovi Freitas
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Helena Couto Junqueira
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Waleska Kerllen Martins
- Universidade Anhanguera de São Paulo, São Paulo, Brazil; Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Mauricio S Baptista
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Lorena Rigo Gaspar
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
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22
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Pavani C, Severino D, Villa Dos Santos N, Chiarelli-Neto O, Baptista MS. Spectroscopy as a tool to evaluate hair damage and protection. Int J Cosmet Sci 2018; 40:596-603. [PMID: 30431651 DOI: 10.1111/ics.12503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 11/12/2018] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Methods that can be used to analyse hair damage and to support a claim of hair protection are important for the cosmetic industry. There are many approaches available, but they are usually laborious and expensive. The researchers propose a simple fluorescence method that is based upon the emissive properties of damaged hair. METHODS Hair fluorescence was observed when using both fluorimetry and microscopic procedures. The method was developed by comparing native hair with hair that was damaged by UVA and visible light. RESULTS Spectroscopic properties (absorption and emission) of hair in the visible range are presented. The changes in the emissive properties of hair during irradiation were characterized and they were correlated with photobleaching, which is due to the generation of singlet oxygen. Emissions were also obtained in the hair shafts that had been previously treated with chamomile extract and this treatment was able to avoid hair bleaching. CONCLUSION The emissive properties of hair in the visible range can be used as a tool for the evaluation of hair damage and protection. This method can be useful as a tool in order to claim substantiation.
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Affiliation(s)
- C Pavani
- Programa de Pós-graduação em Biofotônica Aplicada às Ciências da Saúde, Universidade Nove de Julho (UNINOVE), São Paulo, Brasil
| | - D Severino
- Departamento de Bioquímica, Instituto de Química - Universidade de São Paulo, São Paulo, Brasil
| | - N Villa Dos Santos
- Departamento de Bioquímica, Instituto de Química - Universidade de São Paulo, São Paulo, Brasil
| | - O Chiarelli-Neto
- Departamento de Bioquímica, Instituto de Química - Universidade de São Paulo, São Paulo, Brasil
| | - M S Baptista
- Departamento de Bioquímica, Instituto de Química - Universidade de São Paulo, São Paulo, Brasil
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23
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Bol’shakov MA, Ashikhmin AA, Makhneva ZK, Moskalenko AA. Effect of Light with Different Spectral Composition on Cell Growth and Pigment Composition of the Membranes of Purple Sulfur Bacteria Allochromatium minutissimum and Allochromatium vinosum. Microbiology (Reading) 2018. [DOI: 10.1134/s0026261718020042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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24
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Zhang XF, Feng N. Attaching naphthalene derivatives onto BODIPY for generating excited triplet state and singlet oxygen: Tuning PET-based photosensitizer by electron donors. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 189:13-21. [PMID: 28787622 DOI: 10.1016/j.saa.2017.08.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/19/2017] [Accepted: 08/01/2017] [Indexed: 06/07/2023]
Abstract
meso-Naphthalene substituted BODIPY compounds were prepared in a facile one pot reaction. The naphthalene functionalization of BODIPY leads up to a 5-fold increase in the formation efficiency of excited triplet state and singlet oxygen in polar solvents. Steady state and time resolved fluorescence, laser flash photolysis, and quantum chemistry methods were used to reveal the mechanism. All measured data and quantum chemical results suggest that these systems can be viewed as electron donor-acceptor (D-A) pair (BODIPY acts as the acceptor), photoinduced charge transfer (PCT) or photoinduced electron transfer (PET) occurs upon photo excitation (D-A+hν→Dδ+-Aδ-, 0<δ≤1), and the charge recombination induced the formation of triplet state (Dδ+-Aδ-→D-A (T1). These novel PCT- or PET-based photosensitizers (PSs) show different features from traditional PSs, such as the strong tunability by facile structural modification and good selectivity upon medium polarity. The new character for this type of PSs can lead to important applications in organic oxygenation reactions and photodynamic therapy of tumors.
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Affiliation(s)
- Xian-Fu Zhang
- Institute of Applied Photochemistry & Center of Instrumental Analysis, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei Province 066004, China; MPC Technologies, Hamilton, ON L8S 3H4, Canada.
| | - Nan Feng
- Institute of Applied Photochemistry & Center of Instrumental Analysis, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei Province 066004, China
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25
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Lukashev EP, Oleinikov IP, Knox PP, Seifullina NK, Gorokhov VV, Rubin AB. The Effects of ultraviolet irradiation on hybrid films of photosynthetic reaction centers and quantum dots in various organic matrices. Biophysics (Nagoya-shi) 2017. [DOI: 10.1134/s0006350917050128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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26
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Tsubone TM, Martins WK, Pavani C, Junqueira HC, Itri R, Baptista MS. Enhanced efficiency of cell death by lysosome-specific photodamage. Sci Rep 2017; 7:6734. [PMID: 28751688 PMCID: PMC5532215 DOI: 10.1038/s41598-017-06788-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 06/19/2017] [Indexed: 11/08/2022] Open
Abstract
Mobilization of specific mechanisms of regulated cell death is a promising alternative to treat challenging illness such as neurodegenerative disease and cancer. The use of light to activate these mechanisms may provide a route for target-specific therapies. Two asymmetric porphyrins with opposite charges, the negatively charged TPPS2a and the positively charged CisDiMPyP were compared in terms of their properties in membrane mimics and in cells. CisDiMPyP interacts to a larger extent with model membranes and with cells than TPPS2a, due to a favorable electrostatic interaction. CisDiMPyP is also more effective than TPPS2a in damaging membranes. Surprisingly, TPPS2a is more efficient in causing photoinduced cell death. The lethal concentration on cell viability of 50% (LC50) found for TPPS2a was ~3.5 (raw data) and ~5 (considering photosensitizer incorporation) times smaller than for CisDiMPyP. CisDiMPyP damaged mainly mitochondria and triggered short-term phototoxicity by necro-apoptotic cell death. Photoexcitation of TPPS2a promotes mainly lysosomal damage leading to autophagy-associated cell death. Our data shows that an exact damage in lysosome is more effective to diminish proliferation of HeLa cells than a similar damage in mitochondria. Precisely targeting organelles and specifically triggering regulated cell death mechanisms shall help in the development of new organelle-target therapies.
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Affiliation(s)
| | - Waleska Kerllen Martins
- Instituto de Química, Universidade de São Paulo, São Paulo-SP, Brazil
- Universidade Santo Amaro, São Paulo-SP, Brazil
| | - Christiane Pavani
- Instituto de Química, Universidade de São Paulo, São Paulo-SP, Brazil
- Universidade Nove de Julho, São Paulo-SP, Brazil
| | | | - Rosangela Itri
- Instituto de Física, Universidade de São Paulo, São Paulo-SP, Brazil
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Yagura T, Schuch AP, Garcia CCM, Rocha CRR, Moreno NC, Angeli JPF, Mendes D, Severino D, Bianchini Sanchez A, Di Mascio P, de Medeiros MHG, Menck CFM. Direct participation of DNA in the formation of singlet oxygen and base damage under UVA irradiation. Free Radic Biol Med 2017; 108:86-93. [PMID: 28323132 DOI: 10.1016/j.freeradbiomed.2017.03.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 03/16/2017] [Accepted: 03/16/2017] [Indexed: 12/24/2022]
Abstract
UVA light is hardly absorbed by the DNA molecule, but recent works point to a direct mechanism of DNA lesion by these wavelengths. UVA light also excite endogenous chromophores, which causes DNA damage through ROS. In this study, DNA samples were irradiated with UVA light in different conditions to investigate possible mechanisms involved in the induction of DNA damage. The different types of DNA lesions formed after irradiation were determined through the use of endonucleases, which recognize and cleave sites containing oxidized bases and cyclobutane pyrimidine dimers (CPDs), as well as through antibody recognition. The formation of 8-oxo-7,8-dihydro-2'-deoxyguanine (8-oxodG) was also studied in more detail using electrochemical detection. The results show that high NaCl concentration and concentrated DNA are capable of reducing the induction of CPDs. Moreover, concerning damage caused by oxidative stress, the presence of sodium azide and metal chelators reduce their induction, while deuterated water increases the amounts of oxidized bases, confirming the involvement of singlet oxygen in the generation of these lesions. Curiously, however, high concentrations of DNA also enhanced the formation of oxidized bases, in a reaction that paralleled the increase in the formation of singlet oxygen in the solution. This was interpreted as being due to an intrinsic photosensitization mechanism, depending directly on the DNA molecule to absorb UVA and generate singlet oxygen. Therefore, the DNA molecule itself may act as a chromophore for UVA light, locally producing a damaging agent, which may lead to even greater concerns about the deleterious impact of sunlight.
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Affiliation(s)
- Teiti Yagura
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - André Passaglia Schuch
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil; Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, 97110-970 Santa Maria, RS, Brazil
| | - Camila Carrião Machado Garcia
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil; Núcleo de Pesquisa em Ciências Biológicas & Departamento de Ciências Biológicas, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto, 35400-000 Ouro Preto, MG, Brazil
| | - Clarissa Ribeiro Reily Rocha
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - Natália Cestari Moreno
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - José Pedro Friedmann Angeli
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - Davi Mendes
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - Divinomar Severino
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - Angelica Bianchini Sanchez
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - Paolo Di Mascio
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | | | - Carlos Frederico Martins Menck
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil.
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28
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Müller KMH, Berghoff BA, Eisenhardt BD, Remes B, Klug G. Characteristics of Pos19 - A Small Coding RNA in the Oxidative Stress Response of Rhodobacter sphaeroides. PLoS One 2016; 11:e0163425. [PMID: 27669425 PMCID: PMC5036791 DOI: 10.1371/journal.pone.0163425] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/08/2016] [Indexed: 02/07/2023] Open
Abstract
The phototrophic bacterium Rhodobacter sphaeroides induces several small RNAs (sRNAs) when singlet oxygen (1O2) levels are elevated, a situation also referred to as photo-oxidative stress. An RNA-seq study identified the RSs0019 sRNA, which is renamed Pos19 (photo-oxidative stress induced sRNA 19). Pos19 is part of the RpoE regulon and consequently induced upon 1O2 and peroxide stress. The 219 nt long Pos19 transcript contains a small open reading frame (sORF) of 150 nt, which is translated in vivo. Over-expression of Pos19 results in reduced mRNA levels for several genes, of which numerous are involved in sulfur metabolism. The negative effect on the potential targets is maintained even when translation of the sORF is abolished, arguing that regulation is entailed by the sRNA itself. Reporter studies further revealed that regulation of the most affected mRNA, namely RSP_0557, by Pos19 is Hfq-dependent. Direct binding of Pos19 to Hfq was shown by co-immunoprecipitation. Physiological experiments indicated Pos19 to be involved in the balance of glutathione biosynthesis. Moreover, a lack of Pos19 leads to elevated reactive oxygen species levels. Taken together our data identify the sRNA Pos19 as a coding sRNA with a distinct expression pattern and potential role under oxidative stress in the phototrophic bacterium R. sphaeroides.
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Affiliation(s)
- Katrin M. H. Müller
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität, Heinrich-Buff-Ring 26, 35392, Giessen, Germany
| | - Bork A. Berghoff
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität, Heinrich-Buff-Ring 26, 35392, Giessen, Germany
| | - Benjamin D. Eisenhardt
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität, Heinrich-Buff-Ring 26, 35392, Giessen, Germany
| | - Bernhard Remes
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität, Heinrich-Buff-Ring 26, 35392, Giessen, Germany
| | - Gabriele Klug
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität, Heinrich-Buff-Ring 26, 35392, Giessen, Germany
- * E-mail:
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29
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Białek R, Burdziński G, Jones MR, Gibasiewicz K. Bacteriopheophytin triplet state in Rhodobacter sphaeroides reaction centers. PHOTOSYNTHESIS RESEARCH 2016; 129:205-216. [PMID: 27368166 PMCID: PMC4935742 DOI: 10.1007/s11120-016-0290-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 06/21/2016] [Indexed: 06/06/2023]
Abstract
It is well established that photoexcitation of Rhodobacter sphaeroides reaction centers (RC) with reduced quinone acceptors results in the formation of a triplet state localized on the primary electron donor P with a significant yield. The energy of this long-lived and therefore potentially damaging excited state is then efficiently quenched by energy transfer to the RC spheroidenone carotenoid, with its subsequent decay to the ground state by intersystem crossing. In this contribution, we present a detailed transient absorption study of triplet states in a set of mutated RCs characterized by different efficiencies of triplet formation that correlate with lifetimes of the initial charge-separated state P(+)H A (-) . On a microsecond time scale, two types of triplet state were detected: in addition to the well-known spheroidenone triplet state with a lifetime of ~4 μs, in some RCs we discovered a bacteriopheophytin triplet state with a lifetime of ~40 μs. As expected, the yield of the carotenoid triplet increased approximately linearly with the lifetime of P(+)H A (-) , reaching the value of 42 % for one of the mutants. However, surprisingly, the yield of the bacteriopheophytin triplet was the highest in RCs with the shortest P(+)H A (-) lifetime and the smallest yield of carotenoid triplet. For these the estimated yield of bacteriopheophytin triplet was comparable with the yield of the carotenoid triplet, reaching a value of ~7 %. Possible mechanisms of formation of the bacteriopheophytin triplet state are discussed.
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Affiliation(s)
- Rafał Białek
- Faculty of Physics, Adam Mickiewicz University in Poznań, ul. Umultowska 85, 61-614, Poznan, Poland.
| | - Gotard Burdziński
- Faculty of Physics, Adam Mickiewicz University in Poznań, ul. Umultowska 85, 61-614, Poznan, Poland
| | - Michael R Jones
- School of Biochemistry, Medical Sciences Building, University of Bristol, University Walk, Bristol, BS8 1TD, UK
| | - Krzysztof Gibasiewicz
- Faculty of Physics, Adam Mickiewicz University in Poznań, ul. Umultowska 85, 61-614, Poznan, Poland
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Nagy L, Kiss V, Brumfeld V, Osvay K, Börzsönyi Á, Magyar M, Szabó T, Dorogi M, Malkin S. Thermal Effects and Structural Changes of Photosynthetic Reaction Centers Characterized by Wide Frequency Band Hydrophone: Effects of Carotenoids and Terbutryn. Photochem Photobiol 2015; 91:1368-75. [PMID: 26277346 DOI: 10.1111/php.12511] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Accepted: 08/06/2015] [Indexed: 11/30/2022]
Affiliation(s)
- László Nagy
- Department of Medical Physics and Informatics; University of Szeged; Szeged Hungary
| | - Vladimir Kiss
- Department of Biological Chemistry; Weizmann Institute of Science; Rehovot Israel
| | - Vlad Brumfeld
- Department of Chemical Research Support; Weizmann Institute of Science; Rehovot Israel
| | - Károly Osvay
- Department of Optics and Quantum Electronics; University of Szeged; Szeged Hungary
| | - Ádám Börzsönyi
- Department of Optics and Quantum Electronics; University of Szeged; Szeged Hungary
| | - Melinda Magyar
- Department of Medical Physics and Informatics; University of Szeged; Szeged Hungary
| | - Tibor Szabó
- Department of Medical Physics and Informatics; University of Szeged; Szeged Hungary
| | - Márta Dorogi
- Biophotonics R&D Ltd; Szeged Hungary
- Institute of Plant Biology; Biological Research Center; Hungarian Academy of Sciences; Szeged Hungary
| | - Shmuel Malkin
- Department of Biological Chemistry; Weizmann Institute of Science; Rehovot Israel
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A cluster of four homologous small RNAs modulates C1 metabolism and the pyruvate dehydrogenase complex in Rhodobacter sphaeroides under various stress conditions. J Bacteriol 2015; 197:1839-52. [PMID: 25777678 DOI: 10.1128/jb.02475-14] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 03/09/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED In bacteria, regulatory RNAs play an important role in the regulation and balancing of many cellular processes and stress responses. Among these regulatory RNAs, trans-encoded small RNAs (sRNAs) are of particular interest since one sRNA can lead to the regulation of multiple target mRNAs. In the purple bacterium Rhodobacter sphaeroides, several sRNAs are induced by oxidative stress. In this study, we focused on the functional characterization of four homologous sRNAs that are cotranscribed with the gene for the conserved hypothetical protein RSP_6037, a genetic arrangement described for only a few sRNAs until now. Each of the four sRNAs is characterized by two stem-loops that carry CCUCCUCCC motifs in their loops. They are induced under oxidative stress, as well as by various other stress conditions, and were therefore renamed here sRNAs CcsR1 to CcsR4 (CcsR1-4) for conserved CCUCCUCCC motif stress-induced RNAs 1 to 4. Increased CcsR1-4 expression decreases the expression of genes involved in C1 metabolism or encoding components of the pyruvate dehydrogenase complex either directly by binding to their target mRNAs or indirectly. One of the CcsR1-4 target mRNAs encodes the transcriptional regulator FlhR, an activator of glutathione-dependent methanol/formaldehyde metabolism. Downregulation of this glutathione-dependent pathway increases the pool of glutathione, which helps to counteract oxidative stress. The FlhR-dependent downregulation of the pyruvate dehydrogenase complex reduces a primary target of reactive oxygen species and reduces aerobic electron transport, a main source of reactive oxygen species. Our findings reveal a previously unknown strategy used by bacteria to counteract oxidative stress. IMPORTANCE Phototrophic organisms have to cope with photo-oxidative stress due to the function of chlorophylls as photosensitizers for the formation of singlet oxygen. Our study assigns an important role in photo-oxidative stress resistance to a cluster of four homologous sRNAs in the anoxygenic phototrophic bacterium Rhodobacter sphaeroides. We reveal a function of these regulatory RNAs in the fine-tuning of C1 metabolism. A model that relates oxidative stress defense to C1 metabolism is presented.
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Chiarelli-Neto O, Ferreira AS, Martins WK, Pavani C, Severino D, Faião-Flores F, Maria-Engler SS, Aliprandini E, Martinez GR, Di Mascio P, Medeiros MHG, Baptista MS. Melanin photosensitization and the effect of visible light on epithelial cells. PLoS One 2014; 9:e113266. [PMID: 25405352 PMCID: PMC4236153 DOI: 10.1371/journal.pone.0113266] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 10/06/2014] [Indexed: 11/18/2022] Open
Abstract
Protecting human skin from sun exposure is a complex issue that involves unclear aspects of the interaction between light and tissue. A persistent misconception is that visible light is safe for the skin, although several lines of evidence suggest otherwise. Here, we show that visible light can damage melanocytes through melanin photosensitization and singlet oxygen (1O2) generation, thus decreasing cell viability, increasing membrane permeability, and causing both DNA photo-oxidation and necro-apoptotic cell death. UVA (355 nm) and visible (532 nm) light photosensitize 1O2 with similar yields, and pheomelanin is more efficient than eumelanin at generating 1O2 and resisting photobleaching. Although melanin can protect against the cellular damage induced by UVB, exposure to visible light leads to pre-mutagenic DNA lesions (i.e., Fpg- and Endo III-sensitive modifications); these DNA lesions may be mutagenic and may cause photoaging, as well as other health problems, such as skin cancer.
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Affiliation(s)
- Orlando Chiarelli-Neto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Alan Silva Ferreira
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Waleska Kerllen Martins
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Christiane Pavani
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Divinomar Severino
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Fernanda Faião-Flores
- Departamento de Análises Clínicas, Faculdade de Ciências Farmacêuticas-USP, São Paulo, Brazil
| | | | - Eduardo Aliprandini
- Departamento de Bioquímica e Biologia Molecular, Setor de Ciências Biológicas, Universidade Federal do Paraná, Curitiba, Brazil
| | - Glaucia R. Martinez
- Departamento de Bioquímica e Biologia Molecular, Setor de Ciências Biológicas, Universidade Federal do Paraná, Curitiba, Brazil
| | - Paolo Di Mascio
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Marisa H. G. Medeiros
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Maurício S. Baptista
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
- * E-mail:
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Itri R, Junqueira HC, Mertins O, Baptista MS. Membrane changes under oxidative stress: the impact of oxidized lipids. Biophys Rev 2014; 6:47-61. [PMID: 28509959 DOI: 10.1007/s12551-013-0128-9] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Accepted: 12/03/2013] [Indexed: 12/11/2022] Open
Abstract
Studying photosensitized oxidation of unsaturated phospholipids is of importance for understanding the basic processes underlying photodynamic therapy, photoaging and many other biological dysfunctions. In this review we show that the giant unilamellar vesicle, when used as a simplified model of biological membranes, is a powerful tool to investigate how in situ photogenerated oxidative species impact the phospholipid bilayer. The extent of membrane damage can be modulated by choosing a specific photosensitizer (PS) which is activated by light irradiation and can react by either type I and or type II mechanism. We will show that type II PS generates only singlet oxygen which reacts to the phospholipid acyl double bond. The byproduct thus formed is a lipid hydroperoxide which accumulates in the membrane as a function of singlet oxygen production and induces an increase in its area without significantly affecting membrane permeability. The presence of a lipid hydroperoxide can also play an important role in the formation of the lipid domain for mimetic plasma membranes. Lipid hydroperoxides can be also transformed in shortened chain compounds, such as aldehydes and carboxylic acids, in the presence of a PS that reacts via the type I mechanism. The presence of such byproducts may form hydrophilic pores in the membrane for moderate oxidative stress or promote membrane disruption for massive oxidation. Our results provide a new tool to explore membrane response to an oxidative stress and may have implications in biological signaling of redox misbalance.
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Affiliation(s)
- Rosangela Itri
- Departamento de Física Aplicada, Instituto de Física, Universidade de São Paulo, São Paulo, Brazil.
| | - Helena C Junqueira
- Departamento de Física Aplicada, Instituto de Física, Universidade de São Paulo, São Paulo, Brazil
| | - Omar Mertins
- Departamento de Física Aplicada, Instituto de Física, Universidade de São Paulo, São Paulo, Brazil
| | - Maurício S Baptista
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
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Mank NN, Berghoff BA, Klug G. A mixed incoherent feed-forward loop contributes to the regulation of bacterial photosynthesis genes. RNA Biol 2013; 10:347-52. [PMID: 23392242 PMCID: PMC3672276 DOI: 10.4161/rna.23769] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Living cells use a variety of regulatory network motifs for accurate gene expression in response to changes in their environment or during differentiation processes. In Rhodobacter sphaeroides, a complex regulatory network controls expression of photosynthesis genes to guarantee optimal energy supply on one hand and to avoid photooxidative stress on the other hand. Recently, we identified a mixed incoherent feed-forward loop comprising the transcription factor PrrA, the sRNA PcrZ and photosynthesis target genes as part of this regulatory network. This point-of-view provides a comparison to other described feed-forward loops and discusses the physiological relevance of PcrZ in more detail.
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Affiliation(s)
- Nils N Mank
- Institut für Mikrobiologie und Molekularbiologie; Universität Giessen; Giessen, Germany
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Uchoa AF, Oliveira CS, Baptista MS. Relationship between structure and photoactivity of porphyrins derived from protoporphyrin IX. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s108842461000263x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Protoporphyrin (Pp IX) derivatives were prepared to study the relationship between photosensitizer structure and photoactivity, with an emphasis on understanding the role of membrane interactions in the efficiency of photosensitizers used in photodynamic therapy (PDT). The synthetic strategies described here aimed at changing protoporphyrin periferic groups, varying overall charge and oil/water partition, while maintaining their photochemical properties. Three synthetic routes were used: (1) modification of Pp IX at positions 31 and 81 by addition of alkyl amine groups of different lengths (compounds 2–5), (2) change of Pp IX at positions 133 and 173, generating alkyl amines (compounds 6 and 7, a phosphate amine (compound 8, and quarternary ammonium compounds (compounds 9 and 10), and (3) amine-alkylation of Hematoporphyrin IX (Hp IX) at positions 31, 81, 133 and 173(compound 12). Strategy 1 leads to hydrophobic compounds with low photocytotoxicity. Strategy 2 leads to compounds 6–10 that have high levels of binding/incorporation in vesicles, mitochondria and cells, which are indicative of high bioavailability. Addition of the phosphate group (compound 8), generates an anionic compound that has low liposome and cell incorporation, plus low photocytotoxicity. Compound 12 has intermediate incorporation and photocytotoxic properties. Compound modification is also associated with changes in their sub-cellular localization: 30% of 8 (anionic) is found in mitochondria as compared to 95% of compound 10 (cationic). Photocytotoxicity was shown to be highly correlated with membrane affinity, which depends on the asymmetrical and amphiphilic characters of sens, as well as with sub-cellular localization.
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Affiliation(s)
- Adjaci F. Uchoa
- Instituto de Química, Departamento de Bioquímica e Departmamento de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes 748, São Paulo SP 05508-900, Brazil
| | - Carla S. Oliveira
- Department of Morphophysiology, Center of Biological Sciences and of Health, Biochemistry Laboratory, Universidade do Mato Grosso do Sul, Cidade Universitária, Campo Grande MS 79070-900, Brazil
| | - Mauricio S. Baptista
- Instituto de Química, Departamento de Bioquímica e Departmamento de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes 748, São Paulo SP 05508-900, Brazil
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Abstract
Singlet oxygen is the primary agent of photooxidative stress in microorganisms. In photosynthetic microorganisms, sensitized generation by pigments of the photosystems is the main source of singlet oxygen and, in nonphotosynthetic microorganisms, cellular cofactors such as flavins, rhodopsins, quinones, and porphyrins serve as photosensitizer. Singlet oxygen rapidly reacts with a wide range of cellular macromolecules including proteins, lipids, DNA, and RNA, and thereby further reactive substances including organic peroxides and sulfoxides are formed. Microorganisms that face high light intensities or exhibit potent photosensitizers have evolved specific mechanisms to prevent photooxidative stress. These mechanisms include the use of quenchers, such as carotenoids, which interact either with excited photosensitizer molecules or singlet oxygen itself to prevent damage of cellular molecules. Scavengers like glutathione react with singlet oxygen. Despite those protection mechanisms, damage by reactions with singlet oxygen on cellular macromolecules disturbs cellular functions. Microorganisms that regularly face photooxidative stress have evolved specific systems to sense singlet oxygen and tightly control the removal of singlet oxygen reaction products. Responses to photooxidative stress have been investigated in a range of photosynthetic and nonphotosynthetic microorganisms. However, detailed knowledge on the regulation of this response has only been obtained for the phototrophic alpha-proteobacterium Rhodobacter sphaeroides. In this organism and in related proteobacteria, the extracytoplasmic function (ECF) sigma factor RpoE is released from the cognate antisigma factor ChrR in the presence of singlet oxygen and triggers the expression of genes providing protection against photooxidative stress. Recent experiments show that singlet oxygen acts as a signal, which is sensed by yet unknown components and leads to proteolysis of ChrR. RpoE induces expression of a second alternative sigma factor, RpoH(II), which controls a large set of genes that partially overlaps with the heat-shock response controlled by RpoH(I). In addition to the transcriptional control of gene regulation by alternative sigma factors, a set of noncoding small RNAs (sRNAs) appear to affect the synthesis of several proteins involved in the response to photooxidative stress. The interaction of mRNA targets with those sRNAs is usually mediated by the RNA chaperone Hfq. Deletion of the gene encoding Hfq leads to a singlet oxygen-sensitive phenotype, which underlines the control of gene regulation on the posttranscriptional level by sRNAs in R. sphaeroides. Hence, a complex network of different regulatory components controls the defense against photooxidative stress in anoxygenic photosynthetic bacteria.
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Affiliation(s)
- J Glaeser
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität Giessen, Giessen, Germany
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Uchoa AF, de Oliveira KT, Baptista MS, Bortoluzzi AJ, Iamamoto Y, Serra OA. Chlorin photosensitizers sterically designed to prevent self-aggregation. J Org Chem 2011; 76:8824-32. [PMID: 21932835 DOI: 10.1021/jo201568n] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The synthesis and photophysical evaluation of new chlorin derivatives are described. The Diels-Alder reaction between protoporphyrin IX dimethyl ester and substituted maleimides furnishes endo-adducts that completely prevent the self-aggregation of the chlorins. Fluorescence, resonant light scattering (RLS) and (1)H NMR experiments, as well as X-ray crystallographic have demonstrated that the configurational arrangement of the synthesized chlorins prevent π-stacking interactions between macrocycles, thus indicating that it is a nonaggregating photosensitizer with high singlet oxygen (Φ(Δ)) and fluorescence (Φ(f)) quantum yields. Our results show that this type of synthetic strategy may provide the lead to a new generation of PDT photosensitizers.
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Affiliation(s)
- Adjaci F Uchoa
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, 14040-901, Ribeirão Preto-SP, Brazil.
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Chiarelli-Neto O, Pavani C, Ferreira AS, Uchoa AF, Severino D, Baptista MS. Generation and suppression of singlet oxygen in hair by photosensitization of melanin. Free Radic Biol Med 2011; 51:1195-202. [PMID: 21723388 DOI: 10.1016/j.freeradbiomed.2011.06.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 06/06/2011] [Accepted: 06/07/2011] [Indexed: 01/20/2023]
Abstract
We have studied the spectroscopic properties of hair (white, blond, red, brown, and black) under illumination with visible light, giving special emphasis to the photoinduced generation of singlet oxygen ((1)O(2)). Irradiation of hair shafts (λ(ex)>400 nm) changed their properties by degrading the melanin. Formation of C3 hydroperoxides in the melanin indol groups was proven by (1)H NMR. After 532-nm excitation, all hair shafts presented the characteristic (1)O(2) emission (λ(em)=1270 nm), whose intensity varied inversely with the melanin content. (1)O(2) lifetime was also shown to vary with hair type, being five times shorter in black hair than in blond hair, indicating the role of melanin as a (1)O(2) suppressor. Lifetime ranged from tenths of a nanosecond to a few microseconds, which is much shorter than the lifetime expected for (1)O(2) in the solvents in which the hair shafts were suspended, indicating that (1)O(2) is generated and suppressed inside the hair structure. Both eumelanin and pheomelanin were shown to produce and to suppress (1)O(2), with similar efficiencies. The higher amount of (1)O(2) generated in blond hair and its longer lifetime is compatible with the stronger damage that light exposure causes in blond hair. We propose a model to explain the formation and suppression of (1)O(2) in hair by photosensitization of melanin with visible light and the deleterious effects that an excess of visible light may cause in hair and skin.
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Affiliation(s)
- Orlando Chiarelli-Neto
- Department of Biochemistry, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05509–900, Brazil
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Oliveira CS, Turchiello R, Kowaltowski AJ, Indig GL, Baptista MS. Major determinants of photoinduced cell death: Subcellular localization versus photosensitization efficiency. Free Radic Biol Med 2011; 51:824-33. [PMID: 21664269 DOI: 10.1016/j.freeradbiomed.2011.05.023] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 05/15/2011] [Accepted: 05/19/2011] [Indexed: 10/18/2022]
Abstract
We present a study on whether and to what extent subcellular localization may compete favorably with photosensitization efficiency with respect to the overall efficiency of photoinduced cell death. We have compared the efficiency with which two cationic photosensitizers, namely methylene blue (MB) and crystal violet (CV), induce the photoinduced death of human cervical adenocarcinoma (HeLa) cells. Whereas MB is well known to generate singlet oxygen and related triplet excited species with high quantum yields in a variety of biological and chemical environments (i.e., acting as a typical type II photosensitizer), the highly mitochondria-specific CV produces triplet species and singlet oxygen with low yields, acting mostly via the classical type I mechanism (e.g., via free radicals). The findings described here indicate that the presumably more phototoxic type II photosensitizer (MB) does not lead to higher degrees of cell death compared to the type I (CV) photosensitizer. In fact, CV kills cells with the same efficiency as MB, generating at least 10 times fewer photoinduced reactive species. Therefore, subcellular localization is indeed more important than photochemical reactivity in terms of overall cell killing, with mitochondrial localization representing a highly desirable property for the development of more specific/efficient photosensitizers for photodynamic therapy applications.
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Affiliation(s)
- Carla S Oliveira
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
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Berghoff BA, Glaeser J, Sharma CM, Zobawa M, Lottspeich F, Vogel J, Klug G. Contribution of Hfq to photooxidative stress resistance and global regulation in Rhodobacter sphaeroides. Mol Microbiol 2011; 80:1479-95. [PMID: 21535243 DOI: 10.1111/j.1365-2958.2011.07658.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The photosynthetic alphaproteobacterium Rhodobacter sphaeroides has to cope with photooxidative stress that is caused by the bacteriochlorophyll a-mediated formation of singlet oxygen ((1)O(2)). Exposure to (1)O(2) induces the alternative sigma factors RpoE and RpoH(II) which then promote transcription of photooxidative stress-related genes, including small RNAs (sRNAs). The ubiquitous RNA chaperone Hfq is well established to interact with and facilitate the base-pairing of sRNAs and target mRNAs to influence mRNA stability and/or translation. Here we report on the pleiotropic phenotype of a Δhfq mutant of R. sphaeroides, which is less pigmented, produces minicells and is more sensitive to (1)O(2). The higher (1)O(2) sensitivity of the Δhfq mutant is paralleled by a reduced RpoE activity and a disordered induction of RpoH(II)-dependent genes. We used co-immunoprecipitation of FLAG-tagged Hfq combined with RNA-seq to identify association of at least 25 sRNAs and of mRNAs encoding cell division proteins and ribosomal proteins with Hfq. Remarkably, > 70% of the Hfq-bound sRNAs are (1)O(2)-affected. Proteomics analysis of the Hfq-deficient strain revealed an impact of Hfq on amino acid transport and metabolic functions. Our data demonstrate for the first time an involvement of Hfq in regulation of photosynthesis genes and in the photooxidative stress response.
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Affiliation(s)
- Bork A Berghoff
- Institut für Mikrobiologie und Molekularbiologie, Justus-Liebig-Universität, Heinrich-Buff-Ring 26, 35392 Gießen, Germany
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Silva PR, Vono LLR, Espósito BP, Baptista MS, Rossi LM. Enhancement of hematoporphyrin IX potential for photodynamic therapy by entrapment in silica nanospheres. Phys Chem Chem Phys 2011; 13:14946-52. [DOI: 10.1039/c1cp21525f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Baptista MS, Wainwright M. Photodynamic antimicrobial chemotherapy (PACT) for the treatment of malaria, leishmaniasis and trypanosomiasis. Braz J Med Biol Res 2010; 44:1-10. [PMID: 21152709 DOI: 10.1590/s0100-879x2010007500141] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2010] [Accepted: 05/10/2010] [Indexed: 12/31/2022] Open
Abstract
A photodynamic effect occurs when photosensitiser molecules absorb light and dissipate the absorbed energy by transferring it to biological acceptors (usually oxygen), generating an excess of reactive species that are able to force cells into death pathways. Several tropical diseases present physiopathological aspects that are accessible to the application of a photosensitiser and local illumination. In addition, disease may be transmitted through infected blood donations, and many of the aetiological agents associated with tropical diseases have been shown to be susceptible to the photodynamic approach. However, there has been no systematic investigation of the application of photoantimicrobial agents in the various presentations, whether to human disease or to the disinfection of blood products or even as photo-insecticides. We aim in this review to report the advances in the photoantimicrobial approach that are beneficial to the field of anti-parasite therapy and also have the potential to facilitate the development of low-cost/high-efficiency protocols for underserved populations.
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Affiliation(s)
- M S Baptista
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, SP, Brasil.
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43
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Berghoff BA, Glaeser J, Nuss AM, Zobawa M, Lottspeich F, Klug G. Anoxygenic photosynthesis and photooxidative stress: a particular challenge for Roseobacter. Environ Microbiol 2010; 13:775-91. [DOI: 10.1111/j.1462-2920.2010.02381.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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44
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Riske KA, Sudbrack TP, Archilha NL, Uchoa AF, Schroder AP, Marques CM, Baptista MS, Itri R. Giant vesicles under oxidative stress induced by a membrane-anchored photosensitizer. Biophys J 2009; 97:1362-70. [PMID: 19720024 DOI: 10.1016/j.bpj.2009.06.023] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Revised: 06/14/2009] [Accepted: 06/18/2009] [Indexed: 11/27/2022] Open
Abstract
We have synthesized the amphiphile photosensitizer PE-porph consisting of a porphyrin bound to a lipid headgroup. We studied by optical microscopy the response to light irradiation of giant unilamellar vesicles of mixtures of unsaturated phosphatidylcholine lipids and PE-porph. In this configuration, singlet oxygen is produced at the bilayer surface by the anchored porphyrin. Under irradiation, the PE-porph decorated giant unilamellar vesicles exhibit a rapid increase in surface area with concomitant morphological changes. We quantify the surface area increase of the bilayers as a function of time and photosensitizer molar fraction. We attribute this expansion to hydroperoxide formation by the reaction of the singlet oxygen with the unsaturated bonds. Considering data from numeric simulations of relative area increase per phospholipid oxidized (15%), we measure the efficiency of the oxidative reactions. We conclude that for every 270 singlet oxygen molecules produced by the layer of anchored porphyrins, one eventually reacts to generate a hydroperoxide species. Remarkably, the integrity of the membrane is preserved in the full experimental range explored here, up to a hydroperoxide content of 60%, inducing an 8% relative area expansion.
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Affiliation(s)
- Karin A Riske
- Departamento de Biofísica, Universidade Federal de São Paulo, São Paulo, Brazil
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Berghoff BA, Glaeser J, Sharma CM, Vogel J, Klug G. Photooxidative stress-induced and abundant small RNAs in Rhodobacter sphaeroides. Mol Microbiol 2009; 74:1497-512. [PMID: 19906181 DOI: 10.1111/j.1365-2958.2009.06949.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Exposure to oxygen and light generates photooxidative stress by the bacteriochlorophyll a mediated formation of singlet oxygen ((1)O(2)) in Rhodobacter sphaeroides. Our study reports the genome-wide search for small RNAs (sRNAs) involved in the regulatory response to (1)O(2). By using 454 pyrosequencing and Northern blot analysis, we identified 20 sRNAs from R. sphaeroides aerobic cultures or following treatment with (1)O(2) or superoxide (O(-)(2)). One sRNA was specifically induced by (1)O(2) and its expression depends on the extracytoplasmic function sigma factor RpoE. Two sRNAs induced by (1)O(2) and O(-)(2) were cotranscribed with upstream genes preceded by promoters with target sequences for the alternative sigma factors RpoH(I) and RpoH(II). The most abundant sRNA was processed in the presence of (1)O(2) but not by O(-)(2). From this and a second sRNA a conserved 3'-segment accumulated from a larger precursor. Absence of the RNA chaperone Hfq changed the half-lives, abundance and processing of (1)O(2)-affected sRNAs. Orthologues of three sRNA genes are present in different alpha-proteobacteria, but the majority was unique to R. sphaeroides or Rhodobacterales species. Our discovery that abundant sRNAs are affected by (1)O(2) exposure extends the knowledge on the role of sRNAs and Hfq in the regulatory response to oxidative stress.
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Affiliation(s)
- Bork A Berghoff
- Institut für Mikrobiologie und Molekularbiologie, Universität Giessen, Heinrich-Buff-Ring 26, 35392 Giessen, Germany
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Abstract
Singlet oxygen is one of several reactive oxygen species that can destroy biomolecules, microorganisms and other cells. Traditionally, the response to singlet oxygen has been termed photo-oxidative stress, as light-dependent processes in photosynthetic cells are major biological sources of singlet oxygen. Recent work identifying a core set of singlet oxygen stress response genes across various bacterial species highlights the importance of this response for survival by both photosynthetic and non-photosynthetic cells. Here, we review how bacterial cells mount a transcriptional response to photo-oxidative stress in the context of what is known about bacterial stress responses to other reactive oxygen species.
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Affiliation(s)
- Eva C Ziegelhoffer
- Department of Bacteriology, University of Wisconsin-Madison, 1550 Linden Drive, Madison, Wisconsin 53706, USA
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de Oliveira KT, de Assis FF, Ribeiro AO, Neri CR, Fernandes AU, Baptista MS, Lopes NP, Serra OA, Iamamoto Y. Synthesis of Phthalocyanines−ALA Conjugates: Water-Soluble Compounds with Low Aggregation. J Org Chem 2009; 74:7962-5. [DOI: 10.1021/jo901633a] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Kleber T. de Oliveira
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14040-901, Ribeirão Preto−SP, Brazil
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC-UFABC, Rua Santa Adélia 166, Bangu, 09210-170, Santo André−SP, Brazil
| | - Francisco F. de Assis
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14040-901, Ribeirão Preto−SP, Brazil
| | - Anderson O. Ribeiro
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC-UFABC, Rua Santa Adélia 166, Bangu, 09210-170, Santo André−SP, Brazil
| | - Claudio R. Neri
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14040-901, Ribeirão Preto−SP, Brazil
| | - Adjaci U. Fernandes
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14040-901, Ribeirão Preto−SP, Brazil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes 748, Cidade Universitária, 05508-000, São Paulo−SP, Brazil
| | - Mauricio S. Baptista
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes 748, Cidade Universitária, 05508-000, São Paulo−SP, Brazil
| | - Norberto P. Lopes
- Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto−SP, Brazil
| | - Osvaldo A. Serra
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14040-901, Ribeirão Preto−SP, Brazil
| | - Yassuko Iamamoto
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14040-901, Ribeirão Preto−SP, Brazil
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RpoH(II) activates oxidative-stress defense systems and is controlled by RpoE in the singlet oxygen-dependent response in Rhodobacter sphaeroides. J Bacteriol 2008; 191:220-30. [PMID: 18978062 DOI: 10.1128/jb.00925-08] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Photosynthetic organisms need defense systems against photooxidative stress caused by the generation of highly reactive singlet oxygen ((1)O(2)). Here we show that the alternative sigma factor RpoH(II) is required for the expression of important defense factors and that deletion of rpoH(II) leads to increased sensitivity against exposure to (1)O(2) and methylglyoxal in Rhodobacter sphaeroides. The gene encoding RpoH(II) is controlled by RpoE, and thereby a sigma factor cascade is constituted. We provide the first in vivo study that identifies genes controlled by an RpoH(II)-type sigma factor, which is widely distributed in the Alphaproteobacteria. RpoH(II)-dependent genes encode oxidative-stress defense systems, including proteins for the degradation of methylglyoxal, detoxification of peroxides, (1)O(2) scavenging, and redox and iron homeostasis. Our experiments indicate that glutathione (GSH)-dependent mechanisms are involved in the defense against photooxidative stress in photosynthetic bacteria. Therefore, we conclude that systems pivotal for the organism's defense against photooxidative stress are strongly dependent on GSH and are specifically recognized by RpoH(II) in R. sphaeroides.
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de Oliveira KT, Silva AM, Tomé AC, Neves MG, Neri CR, Garcia VS, Serra OA, Iamamoto Y, Cavaleiro JA. Synthesis of new amphiphilic chlorin derivatives from protoporphyrin-IX dimethyl ester. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.06.103] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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