scholarly journals Substantial near-infrared radiation-driven photosynthesis of chlorophyll f-containing cyanobacteria in a natural habitat

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Michael Kühl ◽  
Erik Trampe ◽  
Maria Mosshammer ◽  
Michael Johnson ◽  
Anthony WD Larkum ◽  
...  
Keyword(s):  
Infrared Radiation ◽  
Laser Scanning ◽  
Near Infrared ◽  
Natural Habitat ◽  
Red Light ◽  
Laser Scanning Microscopy ◽  
Oxygenic Photosynthesis ◽  
Confocal Laser ◽  
Near Infrared Radiation ◽  
Molecular Physiology

Far-red absorbing chlorophylls are constitutively present as chlorophyll (Chl) d in the cyanobacterium Acaryochloris marina, or dynamically expressed by synthesis of Chl f, red-shifted phycobiliproteins and minor amounts of Chl d via far-red light photoacclimation in a range of cyanobacteria, which enables them to use near-infrared-radiation (NIR) for oxygenic photosynthesis. While the biochemistry and molecular physiology of Chl f-containing cyanobacteria has been unraveled in culture studies, their ecological significance remains unexplored and no data on their in situ activity exist. With a novel combination of hyperspectral imaging, confocal laser scanning microscopy, and nanoparticle-based O2 imaging, we demonstrate substantial NIR-driven oxygenic photosynthesis by endolithic, Chl f-containing cyanobacteria within natural beachrock biofilms that are widespread on (sub)tropical coastlines. This indicates an important role of NIR-driven oxygenic photosynthesis in primary production of endolithic and other shaded habitats.

scholarly journals Substantial near-infrared radiation-driven photosynthesis of chlorophyll f-containing cyanobacteria in a natural habitat

2019 ◽  
Author(s):  
Michael Kühl ◽  
Erik Trampe ◽  
Maria Mosshammer ◽  
Michael Johnson ◽  
Anthony W. D. Larkum ◽  
...  
Keyword(s):  
Infrared Radiation ◽  
Laser Scanning ◽  
Near Infrared ◽  
Natural Habitat ◽  
Red Light ◽  
Laser Scanning Microscopy ◽  
Oxygenic Photosynthesis ◽  
Confocal Laser ◽  
Near Infrared Radiation ◽  
Molecular Physiology

AbstractFar-red absorbing chlorophylls are constitutively present as Chl d in the cyanobacterium Acaryochloris marina, or dynamically expressed by synthesis of Chl f and red-shifted phycobilins via far-red light photoacclimation in a range of cyanobacteria, which enables them to use near-infrared-radiation (NIR) for oxygenic photosynthesis. While the biochemistry and molecular physiology of Chl f-containing cyanobacteria has been unraveled in culture studies, their ecological significance remains unexplored and no data on their in situ activity exist. With a novel combination of hyperspectral imaging, confocal laser scanning microscopy, and nanoparticle-based O2 imaging, we demonstrate substantial NIR-driven oxygenic photosynthesis by endolithic, Chl f-containing cyanobacteria within natural beachrock biofilms that are widespread on (sub)tropical coastlines. This indicates an important role of NIR-driven oxygenic photosynthesis in primary production of endolithic and other shaded habitats.Impact statementCyanobacteria with chlorophyll f show substantial near-infrared radiation-driven photosynthesis in intertidal habitats.

Use of near-infrared radiation for oxygenic photosynthesis via photon up-conversion

2012 ◽  
Vol 37 (10) ◽  
pp. 8859-8863 ◽  
Author(s):  
Taras Antal ◽  
Emilia Harju ◽  
Laura Pihlgren ◽  
Mika Lastusaari ◽  
Taina Tyystjärvi ◽  
...  
Keyword(s):  
Infrared Radiation ◽  
Near Infrared ◽  
Oxygenic Photosynthesis ◽  
Near Infrared Radiation

scholarly journals Reactive oxygen production induced by near-infrared radiation in three strains of the Chl d-containing cyanobacterium Acaryochloris marina

F1000Research ◽  
2013 ◽  
Vol 2 ◽  
pp. 44 ◽  
Author(s):  
Lars Behrendt ◽  
Marc Staal ◽  
Simona M Cristescu ◽  
Frans JM Harren ◽  
Martin Schliep ◽  
...  
Keyword(s):  
Infrared Radiation ◽  
Near Infrared ◽  
Reactive Oxygen ◽  
Oxygenic Photosynthesis ◽  
Ros Generation ◽  
The Novel ◽  
Light Conditions ◽  
Near Infrared Radiation ◽  
Opposite Behavior ◽  
Acaryochloris Marina

Cyanobacteria in the genus Acaryochloris have largely exchanged Chl a with Chl d, enabling them to harvest near-infrared-radiation (NIR) for oxygenic photosynthesis, a biochemical pathway prone to generate reactive oxygen species (ROS). In this study, ROS production under different light conditions was quantified in three Acaryochloris strains (MBIC11017, HICR111A and the novel strain CRS) using a real-time ethylene detector in conjunction with addition of 2-keto-4-thiomethylbutyric acid, a substrate that is converted to ethylene when reacting with certain types of ROS. In all strains, NIR was found to generate less ROS than visible light (VIS). More ROS was generated if strains MBIC11017 and HICR111A were adapted to NIR and then exposed to VIS, while strain CRS demonstrated the opposite behavior. This is the very first study of ROS generation and suggests that Acaryochloris can avoid a considerable amount of light-induced stress by using NIR instead of VIS for its photosynthesis, adding further evolutionary arguments to their widespread appearance.

scholarly journals Imaging-Guided Delivery of a Hydrophilic Drug to Eukaryotic Cells Based on Its Hydrophobic Ion Pairing with Poly(hexamethylene guanidine) in a Maleated Chitosan Carrier

Molecules ◽  
2021 ◽  
Vol 26 (24) ◽  
pp. 7426
Author(s):  
Sofia A. Zakharenkova ◽  
Marina I. Lebedeva ◽  
Alexandra N. Lebedeva ◽  
Irina A. Doroshenko ◽  
Ksenya Yu Vlasova ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Near Infrared ◽  
Ion Pairs ◽  
Laser Scanning Microscopy ◽  
Breast Adenocarcinoma ◽  
Confocal Laser ◽  
Counter Ion ◽  
Hydrophilic Drug ◽  
Model Drug ◽  
Novel Strategy

Imaging-guided delivery is developed for hydrophobic drugs, and to a much lesser extent, hydrophilic ones. In this work we have designed a novel strategy for real-time monitoring of hydrophilic drug delivery. Traditionally, the drug and the dye are covalently attached to a nanocarrier or are electrostatically adsorbed. Recently, we found an efficient way to bind the drug by ion-paring with an appropriate counter-ion to form the aggregate that embeds a hydrophobic dye with a considerable fluorescence enhancement. We synthesized a series of carbocyanine dyes of hydrophobicity sufficient for solubilization in hydrophobic ion pairs, which restores their emission in the near-infrared (NIR) region upon the formation of the ternary aggregates. To avoid using toxic surfactants, we applied an amphiphilic polymer-oligomer poly(hexamethylene guanidine) (PHMG) as a counter-ion. Сeftriaxone was used as a model hydrophilic drug ensuring the highest fluorescent signal. The so-formed drug–counter-ion–dye aggregates were encapsulated into a cross-linked maleated chitosan carrier. Confocal laser scanning microscopy (CLSM) studies have demonstrated internalization of the encapsulated model drug by breast adenocarcinoma cells at 40 min after treatment. These results suggest the potential application of hydrophobic ion pairs containing an NIR dye in imaging-guided delivery of hydrophilic compounds.

scholarly journals Multifunctional Magneto-Plasmonic Fe3O4/Au Nanocomposites: Approaching Magnetophoretically-Enhanced Photothermal Therapy

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1113
Author(s):  
Iuliia Mukha ◽  
Oksana Chepurna ◽  
Nadiia Vityuk ◽  
Alina Khodko ◽  
Liudmyla Storozhuk ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Laser Irradiation ◽  
Photothermal Therapy ◽  
Laser Scanning ◽  
Near Infrared ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Photochemical Reduction ◽  
Induced Aggregation

Magneto-plasmonic nanocomposites can possess properties inherent to both individual components (iron oxide and gold nanoparticles) and are reported to demonstrate high potential in targeted drug delivery and therapy. Herein, we report on Fe3O4/Au magneto-plasmonic nanocomposites (MPNC) synthesized with the use of amino acid tryptophan via chemical and photochemical reduction of Au ions in the presence of nanosized magnetite. The magnetic field (MF) induced aggregation was accompanied by an increase in the absorption in the near-infrared (NIR) spectral region, which was demonstrated to provide an enhanced photothermal (PT) effect under NIR laser irradiation (at 808 nm). A possibility for therapeutic application of the MPNC was illustrated using cancer cells in vitro. Cultured HeLa cells were treated by MPNC in the presence of MF and without it, following laser irradiation and imaging using confocal laser scanning microscopy. After scanning laser irradiation of the MPNC/MF treated cells, a formation and rise of photothermally-induced microbubbles on the cell surfaces was observed, leading to a damage of the cell membrane and cell destruction. We conclude that the synthesized magneto-plasmonic Fe3O4/Au nanosystems exhibit magnetic field-induced reversible aggregation accompanied by an increase in NIR absorption, allowing for an opportunity to magnetophoretically control and locally enhance a NIR light-induced thermal effect, which holds high promise for the application in photothermal therapy.

Near-infrared confocal laser scanning microscopy of bladder tissue in vivo

Urology ◽  
1999 ◽  
Vol 53 (4) ◽  
pp. 853-857 ◽  
Author(s):  
Frank Koenig ◽  
Salvador González ◽  
W.Matthew White ◽  
Michael Lein ◽  
Milind Rajadhyaksha
Keyword(s):  
Confocal Laser Scanning Microscopy ◽  
Laser Scanning ◽  
Near Infrared ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Scanning Microscopy ◽  
Confocal Laser ◽  
Bladder Tissue

scholarly journals Effect of Photothermal Therapy with Indocyanine Green in Multispecies Biofilm

2021 ◽  
Vol 48 (1) ◽  
pp. 21-30
Author(s):  
Myunghwan Kim ◽  
Howon Park ◽  
Juhyun Lee ◽  
Hyunwoo Seo ◽  
Siyoung Lee
Keyword(s):  
Indocyanine Green ◽  
Diode Laser ◽  
Laser Scanning ◽  
Near Infrared ◽  
Irradiation Time ◽  
Qualitative Evaluation ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Measured Temperature ◽  
Antibacterial Effects

The purpose of this study is to investigate the antibacterial effects of indocyanine green (ICG) and near-infrared diode lasers on multispecies biofilms.Multispecies biofilms of <i>Streptococcus mutans</i>, <i>Lactobacillus casei</i> and <i>Candida albicans</i> were treated with different irradiation time using photosensitizer ICG and 808 nm near-infrared diode laser. Colony forming unit (CFU) was measured, and qualitative evaluation of biofilm was performed with confocal laser scanning microscopy (CLSM). Temperature measurement was conducted to evaluate photothermal effect.In the groups using ICG and diode laser, reduction in CFU was statistically significant, but the difference in antibacterial effect on <i>L. casei</i> and <i>C. albicans</i> with irradiation time was not significant, and similar results were confirmed with CLSM. Groups with ICG and diode laser showed higher temperature elevation than groups without ICG, and results of measured temperature were similar to the range of hyperthermia.In conclusion, ICG and near-infrared diode laser showed antibacterial effects on multispecies biofilms, but studies on protocol are necessary for clinical application.

scholarly journals In Vitro Evidences of Different Fibroblast Morpho-Functional Responses to Red, Near-Infrared and Violet-Blue Photobiomodulation: Clues for Addressing Wound Healing

2020 ◽  
Vol 10 (21) ◽  
pp. 7878
Author(s):  
Flaminia Chellini ◽  
Alessia Tani ◽  
Sandra Zecchi-Orlandini ◽  
Marco Giannelli ◽  
Chiara Sassoli
Keyword(s):  
Wound Healing ◽  
Laser Scanning ◽  
Near Infrared ◽  
Smooth Muscle Actin ◽  
Focal Adhesions ◽  
Laser Scanning Microscopy ◽  
Wound Management ◽  
Matrix Metalloproteinase 2 ◽  
Confocal Laser ◽  
Functional Responses

Although photobiomodulation (PBM) has proven promising to treat wounds, the lack of univocal guidelines and of a thorough understanding of light–tissue interactions hampers its mainstream adoption for wound healing promotion. This study compared murine and human fibroblast responses to PBM by red (635 ± 5 nm), near-infrared (NIR, 808 ± 1 nm), and violet-blue (405 ± 5 nm) light (0.4 J/cm2 energy density, 13 mW/cm2 power density). Cell viability was not altered by PBM treatments. Light and confocal laser scanning microscopy and biochemical analyses showed, in red PBM irradiated cells: F-actin assembly reduction, up-regulated expression of Ki67 proliferation marker and of vinculin in focal adhesions, type-1 collagen down-regulation, matrix metalloproteinase-2 and metalloproteinase-9 expression/functionality increase concomitant to their inhibitors (TIMP-1 and TIMP-2) decrease. Violet-blue and even more NIR PBM stimulated collagen expression/deposition and, likely, cell differentiation towards (proto)myofibroblast phenotype. Indeed, these cells exhibited a higher polygonal surface area, stress fiber-like structures, increased vinculin- and phospho-focal adhesion kinase-rich clusters and α-smooth muscle actin. This study may provide the experimental groundwork to support red, NIR, and violet-blue PBM as potential options to promote proliferative and matrix remodeling/maturation phases of wound healing, targeting fibroblasts, and to suggest the use of combined PBM treatments in the wound management setting.

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