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Milene N O Moritz, Joyce L S Gonçalves, Irwin A P Linares, Janice R Perussi, Kleber T de Oliveira
An amphiphilic chlorin derivative (CHL-T) was prepared from methylpheophorbide a (CHL) and 2-Amino-2-(hydroxymethyl)-1,3-propanediol (TRISMA(®)). The new chlorin was compared to other dyes (CHL and Hypericin) in relation to photophysical and photobiological activities in tumor and non-tumor cell lines. Cytotoxicity and cell death target were determined to evaluate the CHL-T efficiency, comparing to the precursor CHL and to the well-known dye hypericin (HY). All of the studied compounds exhibited absorption bands in the therapeutic window and presented a small fluorescence quantum yield compared to the reference dye (rhodamine B)...
October 18, 2016: Photodiagnosis and Photodynamic Therapy
Natalie C Sadler, Hans C Bernstein, Matthew R Melnicki, Moiz A Charania, Eric A Hill, Lindsey N Anderson, Matthew E Monroe, Richard D Smith, Alexander S Beliaev, Aaron T Wright
: Photobiologically synthesized hydrogen (H2) gas is carbon-neutral to produce and clean to combust, making it an ideal biofuel. Cyanothece sp. ATCC 51142 is a cyanobacterium capable of performing simultaneous oxygenic photosynthesis and H2 production, a highly perplexing phenomenon because H2 evolving enzymes are O2-sensitive. We employed a systems-level in vivo chemoproteomic profiling approach to explore the cellular dynamics of protein thiol redox, and how thiol redox mediates the function of the dinitrogenase NifHDK, an enzyme complex capable of aerobic hydrogenase activity...
October 14, 2016: Applied and Environmental Microbiology
Xiao-Jing Song, Shu-You Wang, Yin-Long Li, Dong Zhang
The objective of this study was to investigate the spectra characteristics (SC) at wavelengths of 400~1000 nm and 2.5~15.5 μm of pure moxa stick (MS) during its 25-minute burning process using new spectral imaging techniques. Spectral images were collected for the burning pure MS at 5, 10, 15, 20, and 25 min using hyperspectral imaging (HSI) and Fourier transform infrared spectroscopy (FTIR) for the first time. The results showed that, at wavelengths of 400~1000 nm, the spectral range of the cross section of MS burning was 750~980 nm; the peak position was 860 nm...
2016: Evidence-based Complementary and Alternative Medicine: ECAM
Meltem Göksel, Mahmut Durmuş, Devrim Atilla
A series of phthalocyanine-peptide-quencher conjugates (6-9) were synthesized as photosensitizers for photodynamic therapy in cancer treatment. The photophysical, photochemical and photobiological properties of these activatable molecular beacons were also investigated in this study. For this purpose, the fluorescence, singlet oxygen and photodegradation quantum yields and fluorescence lifetime values of the compounds were determined in DMSO solutions. The phototoxicity and cytotoxicity of the systems were studied against the cervical cancer cell line named HeLa for an evaluation of their suitability for photodynamic therapy...
October 5, 2016: Photochemical & Photobiological Sciences
Raymond F Pauszek, Goutham Kodali, M Salim U Siddiqui, Robert J Stanley
Chromophoric biomolecules are exploited as reporters of a diverse set of phenomena, acting as internal distance monitors, environment and redox sensors, and as endogenous imaging probes. The extent to which they can be exploited is based on an accurate knowledge of their fundamental electronic properties. Arguably of greatest importance is a precise knowledge of the direction(s) of the absorption transition dipole moment(s) in the molecular frame of reference. Such is the case for flavins, fluorescent redox cofactors utilized for ground and excited state redox and photochemical processes...
September 29, 2016: Journal of the American Chemical Society
Kevin K Fuller, Robert A Cramer, Michael E Zegans, Jay C Dunlap, Jennifer J Loros
UNLABELLED: The given strain of Aspergillus fumigatus under study varies across laboratories, ranging from a few widely used "standards," e.g., Af293 or CEA10, to locally acquired isolates that may be unique to one investigator. Since experiments concerning physiology or gene function are seldom replicated by others, i.e., in a different A. fumigatus background, the extent to which behavioral heterogeneity exists within the species is poorly understood. As a proxy for assessing such intraspecies variability, we analyzed the light response of 15 A...
2016: MBio
S-J Royer, M Galí, A S Mahajan, O N Ross, G L Pérez, E S Saltzman, R Simó
Emission of the trace gas dimethylsulphide (DMS) from the ocean influences the chemical and optical properties of the atmosphere, and the olfactory landscape for foraging marine birds, turtles and mammals. DMS concentration has been seen to vary across seasons and latitudes with plankton taxonomy and activity, and following the seascape of ocean's physics. However, whether and how does it vary at the time scales of meteorology and day-night cycles is largely unknown. Here we used high-resolution measurements over time and depth within coherent water patches in the open sea to show that DMS concentration responded rapidly but resiliently to mesoscale meteorological perturbation...
2016: Scientific Reports
A K Bauri, Sabine Foro, Quynh Nguyen Nhu Do
The title compound, C12H8O4, is a furan-ocoumarin [systematic name: 4-meth-oxy-7H-furo[3,2-g]chromen-7-one], which was isolated from the Indian herb T. stictocarpum. The mol-ecule is almost planar with an r.m.s. deviation of 0.024 Å for the hetero atoms of the fused-ring system. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming a three-dimensional framework. There are offset π-π inter-actions present involving the coumarin moieties stacking along the a-axis direction [shortest inter-centroid distance = 3...
August 1, 2016: Acta Crystallographica. Section E, Crystallographic Communications
Dominic Deo Androga, Basar Uyar, Harun Koku, Inci Eroglu
For outdoor photobiological hydrogen production, the effective control of temperature in photobioreactors is a challenge. In this work, an internal cooling system for outdoor tubular photobioreactors was designed, built, and tested. The temperatures in the reactors with bacteria were consistently higher than those without bacteria, and were also strongly influenced by solar irradiation and ambient air temperature. The cooling protocol applied successfully kept the reactor temperatures below the threshold limit (38 °C) required for the bioprocess and provided a uniform distribution of temperature along the reactor tube length...
December 2016: Bioprocess and Biosystems Engineering
Kitae Kim, Soon-Kyeong Kwon, Jung-Hoon Yoon, Jihyun F Kim
Dokdonia spp. have been used for investigating the lifestyles of proteorhodopsin-containing photoheterotrophs and for understanding marine photobiology. Here, we report the complete genome sequence of Dokdonia donghaensis DSW-1(T) using the PacBio sequencing platform. It should provide a valuable resource for comparative genomic studies of marine life harboring microbial rhodopsins among others.
2016: Genome Announcements
Kuk-Youn Ju, Jeeun Kang, Jin Ho Chang, Jin-Kyu Lee
The contradictory biological function of eumelanin (photoprotection vs photosensitization) has long been a topic of debate in a wide range of disciplines such as chemistry, physics and biology. For understanding full spectrum of eumelanin's photobiological aspect, revealing how eumelanin's complex structural organization dictates its photophysical properties is critical step. Here, we report a practical approach to controlling the hierarchically assembled structure of natural eumelanin, which leads to disassembly of its structure into subunits and oxidized subunits, respectively...
September 12, 2016: Biomacromolecules
Christian Reichardt, Tariq Sainuddin, Maria Wächtler, Susan Monro, Stephan Kupfer, Julien Guthmuller, Stefanie Gräfe, Sherri McFarland, Benjamin Dietzek
The influence of ligand protonation on the photophysics of a ruthenium (Ru) dyad bearing the 2-(1-pyrenyl)-1H-imidazo[4,5-f][1,10]-phenanthroline (ippy) ligand was investigated by time-resolved transient absorption spectroscopy. It was found that changes in the protonation state of the imidazole group led to changes in the electronic configuration of the lowest lying excited state. Formation of the fully deprotonated imidazole anion resulted in excited state signatures that were consistent with a low-lying intraligand (IL) triplet state...
August 18, 2016: Journal of Physical Chemistry. A
Damilola Fajuyigbe, Antony R Young
Terrestrial solar ultraviolet radiation (UVR) exerts both beneficial and adverse effects on human skin. Epidemiological studies show a lower incidence of skin cancer in people with pigmented skins compared to fair skins. This is attributed to photoprotection by epidermal melanin, as is the poorer vitamin D status of those with darker skins. We summarize a wide range of photobiological responses across different skin colours including DNA damage and immunosuppression. Some studies show the generally modest photoprotective properties of melanin, but others show little or no effect...
July 25, 2016: Pigment Cell & Melanoma Research
Meltem Göksel
Zinc(II) phthalocyanine containing [2-(tert-butoxycarbonyl)amino]ethoxy and iodine groups (A and B), as well as their deprotected mono-amino and tri-iodine zinc(II) phthalocyanine (2) were obtained. This structure surrounds by substituents with functional groups. From this perspective it can be used a starting material for many reactions and applications, such as sonogashira coupling, carbodiimide coupling. An example of a first diversification reaction of this compound was obtained with conjugation of a biotin...
September 15, 2016: Bioorganic & Medicinal Chemistry
G A Gourzoulidis, A Achtipis, F V Topalis, M E Kazasidis, D Pantelis, A Markoulis, C Kappas, C A Bourousis
Occupational Health and Safety (OHS) is associated with crucial social, economic, cultural and technical issues. A highly specialized OHS sector deals with the photobiological hazards from artificial optical radiation (AOR), which is divided into visible light, UV and IR emitted during various activities and which is legally covered by European Directive 2006/25/EC. Among the enormous amount of sources emitting AOR, the most important non-coherent ones to consider for health effects to the whole optical range, are arcs created during metal welding...
August 2016: Physica Medica: PM
Spiros S Skourtis, Chaoren Liu, Panayiotis Antoniou, Aaron M Virshup, David N Beratan
Energy transfer with an associated spin change of the donor and acceptor, Dexter energy transfer, is critically important in solar energy harvesting assemblies, damage protection schemes of photobiology, and organometallic opto-electronic materials. Dexter transfer between chemically linked donors and acceptors is bridge mediated, presenting an enticing analogy with bridge-mediated electron and hole transfer. However, Dexter coupling pathways must convey both an electron and a hole from donor to acceptor, and this adds considerable richness to the mediation process...
July 19, 2016: Proceedings of the National Academy of Sciences of the United States of America
A K Bauri, Sabine Foro, Nhu Quynh Nguyen Do
The title furan-ocoumarin, C14H12O4 [systematic name: 9-hy-droxy-2-(prop-1-en-2-yl)-2,3-di-hydro-7H-furo[3,2-g]chromen-7-one], crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. The two mol-ecules differ essentially in the orientation of the propenyl group with respect to the mean plane of the furan-ocoumarin moiety; the O-C(H)-C=C torsion angle is 122.2 (7)° in mol-ecule A and -10.8 (11)° in mol-ecule B. In the crystal, the A and B mol-ecules are linked via O-H⋯O hydrogen bonds, forming zigzag -A-B-A-B- chains propagating along [001]...
April 1, 2016: Acta Crystallographica. Section E, Crystallographic Communications
Jeong-Ho Lee, Jeong-Muk Lim, Palanivel Velmurugan, Yool-Jin Park, Youn-Jong Park, Keuk-Soo Bang, Byung-Taek Oh
We present the simple, eco-friendly synthesis of silver nanoparticles (AgNPs) using sunlight or green, red, blue, or white LED light together with Dryopteris crassirhizoma rhizome extract (DCRE) as the reducing and capping agent. The preliminary indication of AgNP production was a color change from yellowish green to brown after light exposure in the presence of DCRE. Optimization of parameters such as pH, inoculum dose, and metal ion concentration played an important role in achieving nanoparticle production in 30min...
September 2016: Journal of Photochemistry and Photobiology. B, Biology
Cuixia Lu, Zhijin Fan, Da Xing
Phagocytosis and the subsequent destruction of invading pathogens by macrophages are indispensable steps in host immune responses to microbial infections. Low-power laser irradiation (LPLI) has been found to exert photobiological effects on immune responses, but the signaling mechanisms underlying this photobiomodulation of phagocytosis remains largely unknown. Here, we demonstrated for the first time that LPLI enhanced the phagocytic activity of macrophages by stimulating the activation of Rac1. The overexpression of constitutively activated Rac1 clearly enhanced LPLI-induced phagocytosis, whereas the overexpression of dominant negative Rac1 exerted the opposite effect...
September 2016: International Journal of Biochemistry & Cell Biology
Erin A Becker, Andrew I Yao, Phillip M Seitzer, Tobias Kind, Ting Wang, Rich Eigenheer, Katie S Y Shao, Vladimir Yarov-Yarovoy, Marc T Facciotti
Opsins are photosensitive proteins catalyzing light-dependent processes across the tree of life. For both microbial (type 1) and metazoan (type 2) opsins, photosensing depends upon covalent interaction between a retinal chromophore and a conserved lysine residue. Despite recent discoveries of potential opsin homologs lacking this residue, phylogenetic dispersal and functional significance of these abnormal sequences have not yet been investigated. We report discovery of a large group of putatively non-retinal binding opsins, present in a number of fungal and microbial genomes and comprising nearly 30% of opsins in the Halobacteriacea, a model clade for opsin photobiology...
2016: PloS One
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