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Photoprotection systemic

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https://www.readbyqxmd.com/read/28793281/photosynthetic-limitation-and-mechanisms-of-photoprotection-under-drought-and-recovery-of-calotropis-procera-an-evergreen-c3-from-arid-regions
#1
Rebeca Rivas, Gabriella Frosi, Diego G Ramos, Silvia Pereira, Ana M Benko-Iseppon, Mauro G Santos
Calotropis procera is a C3 plant native from arid environmental zones. It is an evergreen, shrubby, non-woody plant with intense photosynthetic metabolism during the dry season. We measured photosynthetic parameters and leaf biochemical traits, such as gas exchange, photochemical parameters, A/Ci analysis, organic solutes, and antioxidant enzymes under controlled conditions in potted plants during drought stress, and following recovery conditions to obtain a better insight in the drought stress responses of C...
July 31, 2017: Plant Physiology and Biochemistry: PPB
https://www.readbyqxmd.com/read/28790428/an-unusual-role-for-the-phytyl-chains-in-the-photoprotection-of-the-chlorophylls-bound-to-water-soluble-chlorophyll-binding-proteins
#2
Alessandro Agostini, Daniel M Palm, Franz-Josef Schmitt, Marco Albertini, Marilena Di Valentin, Harald Paulsen, Donatella Carbonera
Water-Soluble Chlorophyll Proteins (WSCPs) from Brassicaceae are non-photosynthetic proteins which tetramerize upon binding four chlorophyll (Chl) molecules. The bound Chls are highly photostable, despite the lack of bound carotenoids known, in Chl-containing photosynthetic proteins, to act as singlet oxygen and Chl triplet ((3)Chl) quenchers. Although the physiological function of WSCPs is still unclear, it is likely to be related to their biochemical stability and their resistance to photodegradation. To get insight into the origin of this photostability, the properties of the (3)Chl generated in WSCPs upon illumination were investigated...
August 8, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28743100/studies-on-secondary-metabolite-profiling-anti-inflammatory-potential-in-vitro-photoprotective-and-skin-aging-related-enzyme-inhibitory-activities-of-malaxis-acuminata-a-threatened-orchid-of-nutraceutical-importance
#3
Biswajit Bose, Hiranjit Choudhury, Pramod Tandon, Suman Kumaria
Malaxis acuminata D. Don., a small, terrestrial orchid, is endemic to tropical Himalayas at an altitude of 1200-2000m asl. The dried pseudobulbs are important ingredients of century old ayurvedic drug 'Ashtavarga' and a polyherbal immune-booster nutraceutical 'Chyavanprash', known to restore vigour, vitality and youthfulness. Considering tremendous medicinal importance of this threatened orchid species, a detailed study was undertaken for the first time to address its antioxidant potential, secondary metabolite contents and biological activities against skin-aging related enzymes (anti-collagenase, anti-elastase, anti-tyrosinase and xanthine oxidase) and anti-inflammatory activity (5-lipoxygenase and hyaluronidase) in different plant parts of wild and in vitro-derived plants of M...
August 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28692021/additional-families-of-orange-carotenoid-proteins-in-the-photoprotective-system-of-cyanobacteria
#4
Han Bao, Matthew R Melnicki, Emily G Pawlowski, Markus Sutter, Marco Agostoni, Sigal Lechno-Yossef, Fei Cai, Beronda L Montgomery, Cheryl A Kerfeld
The orange carotenoid protein (OCP) is a structurally and functionally modular photoactive protein involved in cyanobacterial photoprotection. Using phylogenomic analysis, we have revealed two new paralogous OCP families, each distributed among taxonomically diverse cyanobacterial genomes. Based on bioinformatic properties and phylogenetic relationships, we named the new families OCP2 and OCPx to distinguish them from the canonical OCP that has been well characterized in Synechocystis, denoted hereafter as OCP1...
July 10, 2017: Nature Plants
https://www.readbyqxmd.com/read/28667107/the-two-cryptochrome-photolyase-family-proteins-fulfill-distinct-roles-in-dna-photorepair-and-regulation-of-conidiation-in-the-gray-mold-fungus-botrytis-cinerea
#5
Kim C Cohrs, Julia Schumacher
The plant pathogenic Leotiomycete Botrytis cinerea is known for the strict regulation of its asexual differentiation programs by the environmental light conditions. Sclerotia are formed in constant darkness, black/near-UV (NUV) light induces conidiation and blue light represses both differentiation programs. Sensing of black/NUV light is attributed to proteins of the cryptochrome/photolyase family (CPF). To elucidate the molecular basis of the photoinduction of conidiation, we functionally characterized the two CPF proteins encoded in the genome of B...
June 30, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28628680/current-perspectives-among-u-s-dermatologists-on-chemoprevention-of-nonmelanoma-skin-cancer-a-survey-based-study
#6
Brittany Oliver, Serena Durrani, Joel L Cohen, Adam J Friedman
<p>Introduction: Nonmelanoma skin cancer (NMSC) is the most common malignancy in the US Primary prevention of NMSC with physical photoprotective measures are often not sufficient to impact skin cancer incidence in high-risk individuals. Chemoprevention is the use of agents to prevent, suppress, and reverse carcinogenic progression. Many agents have been investigated, but preclinical and clinical studies are often inconsistent.</p> <p>Methods: A cross-sectional study was designed to assess current practices, perceptions, and general knowledge of U...
May 1, 2017: Journal of Drugs in Dermatology: JDD
https://www.readbyqxmd.com/read/28619535/evolution-and-regulation-of-bigelowiella-natans-light-harvesting-antenna-system
#7
Jonathan A D Neilson, Pattarasiri Rangsrikitphoti, Dion G Durnford
Bigelowiella natans is a mixotrophic flagellate and member of the chlorarachniophytes (Rhizaria), whose plastid is derived from a green algal endosymbiont. With the completion of the B. natans nuclear genome we are able to begin the analysis of the structure, function and evolution of the photosynthetic apparatus. B. natans has undergone substantial changes in photosystem structure during the evolution of the plastid from a green alga. While Photosystem II (PSII) composition is well conserved, Photosystem I (PSI) composition has undergone a dramatic reduction in accessory protein subunits...
May 31, 2017: Journal of Plant Physiology
https://www.readbyqxmd.com/read/28566797/allochthonous-matter-an-important-factor-shaping-the-phytoplankton-community-in-the-baltic-sea
#8
J Paczkowska, O F Rowe, L Schlüter, C Legrand, B Karlson, A Andersson
It is well-known that nutrients shape phytoplankton communities in marine systems, but in coastal waters allochthonous dissolved organic matter (ADOM) may also be of central importance. We studied how humic substances (proxy of ADOM) and other variables influenced the nutritional strategies, size structure and pigment content of the phytoplankton community along a south-north gradient in the Baltic Sea. During the summer, the proportion of mixotrophs increased gradually from the phosphorus-rich south to the ADOM-rich north, probably due to ADOM-fueled microbes...
January 2017: Journal of Plankton Research
https://www.readbyqxmd.com/read/28487674/uncovering-potential-applications-of-cyanobacteria-and-algal-metabolites-in-biology-agriculture-and-medicine-current-status-and-future-prospects
#9
REVIEW
Rachana Singh, Parul Parihar, Madhulika Singh, Andrzej Bajguz, Jitendra Kumar, Samiksha Singh, Vijay P Singh, Sheo M Prasad
Cyanobacteria and algae having complex photosynthetic systems can channelize absorbed solar energy into other forms of energy for production of food and metabolites. In addition, they are promising biocatalysts and can be used in the field of "white biotechnology" for enhancing the sustainable production of food, metabolites, and green energy sources such as biodiesel. In this review, an endeavor has been made to uncover the significance of various metabolites like phenolics, phytoene/terpenoids, phytols, sterols, free fatty acids, photoprotective compounds (MAAs, scytonemin, carotenoids, polysaccharides, halogenated compounds, etc...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28464994/genotoxic-effects-of-zinc-oxide-nanoparticles-in-nasal-mucosa-cells-are-antagonized-by-titanium-dioxide-nanoparticles
#10
Stephan Hackenberg, Agmal Scherzed, Angela Zapp, Katrin Radeloff, Christian Ginzkey, Thomas Gehrke, Pascal Ickrath, Norbert Kleinsasser
Titanium dioxide nanoparticles (TiO2-NPs) and zinc oxide nanoparticles (ZnO-NPs) are often used in sunscreens and other consumer products due to their photoprotective properties. However, concern exists regarding them possibly causing cyto- and genotoxic effects. The aim of this study was to assess cyto- and genotoxicity of these nanomaterials after single or combined exposure. For this purpose, a battery of cell culture test systems for human nasal mucosa (monolayer, air-liquid interface and mini organ culture) were exposed to 0...
April 2017: Mutation Research. Genetic Toxicology and Environmental Mutagenesis
https://www.readbyqxmd.com/read/28456146/comparative-effects-of-a-fixed-polypodium-leucotomos-pomegranate-combination-versus-polypodium-leucotomos-alone-on-skin-biophysical-parameters
#11
Enzo Emanuele, Marco Bertona, Marco Biagi
OBJECTIVES: Polypodium leucotomos extract is a commonly used systemic photoprotective agent. In an exploratory fashion, the current study aimed to compare the effects of oral supplementation with a fixed Polypodium leucotomos/pomegranate combination (PPmix®) versus Polypodium leucotomos alone (Fernblock®) on skin biophysical parameters of Caucasian adults. METHODS: Forty healthy adult volunteers (20 males and 20 females; mean age: 37.2±5.5 years) were randomized in a 1:1 fashion to a fixed Polypodium leucotomos/pomegranate combination (480 mg/day; n=20) or Polypodium leucotomos alone (480 mg/day; n=20) for 3 months...
February 2017: Neuro Endocrinology Letters
https://www.readbyqxmd.com/read/28448268/the-effect-of-pycnogenol-on-wound-healing-in-diabetic-rats
#12
Elif Dogan, Latif Yanmaz, Semin Gedikli, Ugur Ersoz, Zafer Okumus
Pycnogenol (PYC), an extract of pine bark, is known to have photoprotective, antimicrobial, antioxidant, and anti-inflammatory properties. An in vivo study was conducted to evaluate the effects of PYC treatment on wound healing in 48 adult male Sprague-Dawley rats, of which 24 were injected with a single dose of alloxan to induce diabetes. Three (3) excisional skin wounds (1.3 cm x 1.3 cm x 2 mm) were created in each healthy and diabetic animal. One (1) wound in each animal was left untreated, 1 was treated daily with a cleanser (ethacridine lactate) and covered with silver sulfadiazine (SSD), and 1 was treated with PYC powder (30 mg)...
April 2017: Ostomy/wound Management
https://www.readbyqxmd.com/read/28445834/light-harvesting-antenna-complexes-in-the-moss-physcomitrella-patens-implications-for-the-evolutionary-transition-from-green-algae-to-land-plants
#13
REVIEW
Masakazu Iwai, Makio Yokono
Plants have successfully adapted to a vast range of terrestrial environments during their evolution. To elucidate the evolutionary transition of light-harvesting antenna proteins from green algae to land plants, the moss Physcomitrella patens is ideally placed basally among land plants. Compared to the genomes of green algae and land plants, the P. patens genome codes for more diverse and redundant light-harvesting antenna proteins. It also encodes Lhcb9, which has characteristics not found in other light-harvesting antenna proteins...
April 23, 2017: Current Opinion in Plant Biology
https://www.readbyqxmd.com/read/28445599/growth-engineering-of-synechococcus-elongatus-pcc-7942-for-mixotrophy-under-natural-light-conditions-for-improved-feedstock-production
#14
Aditya Sarnaik, Reena Pandit, Arvind Lali
Synechococcus elongatus PCC 7942 has been widely explored as cyanobacterial cell factory through genetic modifications for production of various value-added compounds. However, successful industrial scale-ups have not been reported for the system predominantly due to its obligate photoautotrophic metabolism and use of artificial light in photobioreactors. Hence, engineering the organism to perform mixotrophy under natural light could serve as an effective solution. Thus, we applied a genetically engineered strain of Synechococcus elongatus PCC 7942 expressing heterologous hexose transporter gene (galP) to perform mixotrophy under natural light in a temperature controlled environmental chamber (EC)...
April 26, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28421106/the-synergistic-responses-of-different-photoprotective-pathways-in-dwarf-bamboo-fargesia-rufa-to-drought-and-subsequent-rewatering
#15
Chenggang Liu, Yanjie Wang, Kaiwen Pan, Qingwei Wang, Jin Liang, Yanqiang Jin, Akash Tariq
Dwarf bamboo-dominated forests are often subjected to temporary periods of drought due to rising air temperature and decreasing rainfall. Nevertheless, the relationship among CO2 assimilation, photoprotective pathways and metabolism of reactive oxygen species (ROS) remains unexplored in bamboo species. Changes in leaf gas exchange, chlorophyll fluorescence, energy partitioning, antioxidative system and compounds related to ROS metabolism in Fargesia rufa plants subjected to drought and subsequent rewatering were analyzed...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28358623/one-target-two-mechanisms-the-impact-of-candidatus-liberibacter-asiaticus-and-its-vector-diaphorina-citri-on-citrus-leaf-pigments
#16
Nabil Killiny, Yasser Nehela
Huanglongbing (HLB) is currently the largest threat to global citrus production. We examined the effect of HLB pathogen 'Candidatus Liberibacter asiaticus' infection or infestation by its vector, Diaphorina citri, on 'Valencia' sweet orange leaf pigments using high-performance liquid chromatography, followed by gene expression analysis for 46 involved genes in carotenoid and chlorophyll biosynthesis pathways. Both 'Ca. L. asiaticus' and D. citri alter the total citrus leaf pigment balance with a greater impact by 'Ca...
July 2017: Molecular Plant-microbe Interactions: MPMI
https://www.readbyqxmd.com/read/28341348/the-impact-of-oral-polypodium-leucotomos-extract-on-ultraviolet-b-response-a-human-clinical-study
#17
Indermeet Kohli, Rubina Shafi, Prescilia Isedeh, James L Griffith, Mohammed S Al-Jamal, Narumol Silpa-Archa, Bradford Jackson, Mohammed Athar, Nikiforos Kollias, Craig A Elmets, Henry W Lim, Iltefat H Hamzavi
BACKGROUND: There is a rationale for adding systemic photoprotective agents to the current photoprotection regimen. OBJECTIVE: This study was designed to objectively evaluate the molecular and photobiologic effects of oral administration of Polypodium leucotomos extract (PLE). METHODS: In all, 22 subjects with Fitzpatrick skin phototype I to III were enrolled. On day 1, subjects were irradiated with visible light, ultraviolet (UV) A1, and UVB (using 308-nm excimer laser)...
July 2017: Journal of the American Academy of Dermatology
https://www.readbyqxmd.com/read/28260501/in-vitro-skin-models-for-the-evaluation-of-sunscreen-based-skin-photoprotection-molecular-methodologies-and-opportunities
#18
Françoise Bernerd, Claire Marionnet
Identifying and understanding the biological events that occur following ultraviolet (UV) exposure are mandatory to elucidate the biological and clinical consequences of sun exposure, and to provide efficient and adequate photoprotection strategies. The main UV-induced biological features (markers related to sunburn, cancer, photoaging immunosuppression, pigmentation), characterized in human skin in vivo, could be reproduced in adapted models of reconstructed skin in vitro, attesting their high relevance in the field of photobiology...
March 3, 2017: Current Medicinal Chemistry
https://www.readbyqxmd.com/read/28257901/effect-of-florfenicol-and-thiamphenicol-exposure-on-the-photosynthesis-and-antioxidant-system-of-microcystis-flos-aquae
#19
Meixian Wang, Yuxuan Zhang, Peiyong Guo
Florfenicol (FF) and thiamphenicol (TAP) are two typical pharmaceuticals used widely as therapeutica antibiotic agents in aquaculture. However, little is known about the potential adverse effects of these two antibiotics on non-target organisms in the aquatic ecosystem. In this study we investigated the effects of FF and TAP on photosynthesis and the antioxidant system of the cyanobacteria Microcystis flos-aquae. Over a concentration range of 0.001-1μg/L, the results showed that both FF and TAP significantly increased the chlorophyll a content of M...
May 2017: Aquatic Toxicology
https://www.readbyqxmd.com/read/28153924/correlations-between-circadian-rhythms-and-growth-in-challenging-environments
#20
Yuri Dakhiya, Duaa Hussien, Eyal Fridman, Moshe Kiflawi, Rachel Green
In plants, the circadian system controls a plethora of processes, many with agronomic importance, such as photosynthesis, photoprotection, stomatal opening, and photoperiodic development, as well as molecular processes, such as gene expression. It has been suggested that modifying circadian rhythms may be a means to manipulate crops to develop improved plants for agriculture. However, there is very little information on how the clock influences the performance of crop plants. We used a noninvasive, high-throughput technique, based on prompt chlorophyll fluorescence, to measure circadian rhythms and demonstrated that the technique works in a range of plants...
March 2017: Plant Physiology
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