Inhibitory effect of molecular hydrogen on C2H2-reducing activity in Anabaena 7120 preilluminated in red or blue light

Hydrobiologia ◽  
1985 ◽  
Vol 123 (3) ◽  
pp. 219-221
Author(s):  
Chen Yin ◽  
Fan Da-wei
Keyword(s):  
Blue Light ◽  
Molecular Hydrogen ◽  
Inhibitory Effect ◽  
Anabaena 7120 ◽  
Reducing Activity

A novel strategy for selective gene delivery by using the inhibitory effect of blue light on jetPRIME-mediated transfection

2015 ◽  
Vol 113 (7) ◽  
pp. 1560-1567
Author(s):  
Minori Dateki ◽  
Osamu Imamura ◽  
Masaaki Arai ◽  
Hidehisa Shimizu ◽  
Kunio Takishima
Keyword(s):  
Gene Delivery ◽  
Blue Light ◽  
Inhibitory Effect ◽  
Novel Strategy

scholarly journals Cysteine: an overlooked energy and carbon source

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Luise Göbbels ◽  
Anja Poehlein ◽  
Albert Dumnitch ◽  
Richard Egelkamp ◽  
Cathrin Kröger ◽  
...  
Keyword(s):  
Carbon Source ◽  
Blue Light ◽  
Metabolic Activity ◽  
Cadmium Sulphide ◽  
Inhibitory Effect ◽  
Arginine Metabolism ◽  
Moorella Thermoacetica ◽  
Acetogenic Bacterium ◽  
Intracellular Storage ◽  
Biological Component

AbstractBiohybrids composed of microorganisms and nanoparticles have emerged as potential systems for bioenergy and high-value compound production from CO2 and light energy, yet the cellular and metabolic processes within the biological component of this system are still elusive. Here we dissect the biohybrid composed of the anaerobic acetogenic bacterium Moorella thermoacetica and cadmium sulphide nanoparticles (CdS) in terms of physiology, metabolism, enzymatics and transcriptomic profiling. Our analyses show that while the organism does not grow on l-cysteine, it is metabolized to acetate in the biohybrid system and this metabolism is independent of CdS or light. CdS cells have higher metabolic activity, despite an inhibitory effect of Cd2+ on key enzymes, because of an intracellular storage compound linked to arginine metabolism. We identify different routes how cysteine and its oxidized form can be innately metabolized by the model acetogen and what intracellular mechanisms are triggered by cysteine, cadmium or blue light.

scholarly journals In Arabidopsis, low blue light enhances phototropism by releasing cryptochrome 1-mediated inhibition of PIF4 expression

2020 ◽  
Author(s):  
Alessandra Boccaccini ◽  
Martina Legris ◽  
Johanna Krahmer ◽  
Laure Allenbach-Petrolati ◽  
Anupama Goyal ◽  
...  
Keyword(s):  
Blue Light ◽  
Solar Spectrum ◽  
Inhibitory Effect ◽  
Phytochrome B ◽  
Growth Responses ◽  
Swiss National Science Foundation ◽  
Etiolated Seedlings ◽  
The University ◽  
Cryptochrome 1 ◽  
Favorable Light

AbstractShade-avoiding plants including Arabidopsis thaliana display a number of growth responses elicited by shade cues including elongation of stem-like structures and repositioning of leaves. Shade also promotes phototropism of de-etiolated seedlings through repression of phytochrome B (phyB) presumably to enhance capture of unfiltered sunlight. Light cues indicative of shade include a reduction in the blue and red portions of the solar spectrum and a low red to far-red ratio. Here we show that in Arabidopsis seedlings both low blue and a low red to far-red ratio are required to rapidly enhance phototropism. However, prolonged low blue treatments through reduced cryptochrome 1 (cry1) activation are sufficient to promote phototropism. The enhanced phototropic response of cry1 mutants in the lab and in response to natural canopies depends on PHYTOCHROME INTERACTING FACTORs (PIFs). In favorable light conditions, cry1 limits the expression of PIF4 while in low blue light PIF4 expression increases, which contributes to phototropic enhancement. The analysis of a quantitative DII auxin reporter indicates that low blue light leads to enhanced auxin levels in the hypocotyl and, upon phototropic stimulation, a steeper auxin gradient across the hypocotyl. We conclude that phototropic enhancement by canopy shade results from the combined activities of phytochrome B and cry1 that converge on PIF regulation.ONE SENTENCE SUMMARYThe persistent depletion of blue light in natural canopy shade relieves the inhibitory effect of cryptochrome 1 on PIF4, enhancing phototropism in de-etiolated Arabidopsis seedlings.Financial supportThis work was supported by the University of Lausanne and a grant from the Swiss National Science foundation (n° 310030B_179558 to C.F.); Human Frontier Science Program organization (HFSP) Grant RPG0054-2013, ANR-12-BSV6-0005 grant (AuxiFlo) to T.V.; The University of Buenos Aires (Grant 20020100100437 to J. J. C.), and Agencia Nacional de Promoción Científica y Tecnológica of Argentina (Grant PICT-2018-01695 to J. J. C.). Alessandra Boccaccini and Martina Legris are funded by Marie Curie fellowships H2020-MSCA-IF-2017 grants CRoSh 796283 and Flat-Leaf 796443 respectively.

The Development of Phototaxis in the Frog (Rana Temporaria)

1963 ◽  
Vol 40 (2) ◽  
pp. 371-379
Author(s):  
W. R. A. MUNTZ
Keyword(s):  
Blue Light ◽  
Rana Temporaria ◽  
Green Light ◽  
Inhibitory Effect ◽  
Synergistic Action ◽  
Excitatory Effect ◽  
Frog Rana Temporaria ◽  
Phototactic Behaviour

1. The development of phototaxis in the frog was studied by testing the behaviour of tadpoles at different stages of their development. The development of the retina at each stage was checked from histological preparations. 2. Young tadpoles responded most strongly to green light (approx. 550 mµ). Gradually the number of responses to green light decreased, while more responses were made to blue light, and also to darkness. Adult frogs respond most strongly to blue light; light of wavelengths longer than about 510 mµ is responded to only slightly more often than darkness. 3. It was concluded that the phototactic behaviour of frogs is probably mediated by a synergistic action of the green rods and the cones, which have an excitatory effect, and which are opposed by an inhibitory effect of the red rods.

scholarly journals Nitrogenase of Klebsiella pneumoniae. Inhibition of acetylene reduction by magnesium ion explained by the formation of an inactive dimagnesium–adenosine triphosphate complex

1974 ◽  
Vol 139 (1) ◽  
pp. 211-214 ◽  
Author(s):  
Roger N. F. Thorneley ◽  
Keith R. Willison
Keyword(s):  
Klebsiella Pneumoniae ◽  
Adenosine Triphosphate ◽  
Acetylene Reduction ◽  
Inhibitory Effect ◽  
Magnesium Ion ◽  
Active Substrate ◽  
Reducing Activity ◽  
Acetylene Reducing Activity

Acetylene-reducing activity of purified nitrogenase from Klebsiella pneumoniae was studied over a range of ATP and Mg2+ concentrations at 15°C, pH7.8. Inhibition at Mg2+ concentrations of 2.5–30mm was due to the formation of the inactive complex, Mg2ATP. At higher Mg2+ concentrations an additional inhibitory effect was observed. The results were consistent with a MgATP complex being the active substrate with an apparent Km(MgATP)=0.4mm.

Influence of timing in the fructosamine assay.

1988 ◽  
Vol 34 (11) ◽  
pp. 2245-2248
Author(s):  
E K Frandsen ◽  
R A Bacchus
Keyword(s):  
Inhibitory Effect ◽  
Protein Glycation ◽  
Secondary Standard ◽  
Alkaline Ph ◽  
Synthetic Compound ◽  
Serum Fructosamine ◽  
Reducing Activity ◽  
Kinetics Of

Abstract The fructosamine assay, based on the measurement of the reducing activity in serum at alkaline pH, provides an index of protein glycation. The reducing activity is expressed in equivalents of 1-deoxy-1-morpholinofructose (DMF) by direct comparison with the activity either of this synthetic compound or with a secondary protein standard calibrated against DMF. This study reports the influence of assay timing on the apparent serum fructosamine concentration. The kinetics of alkaline reducing activity in serum differed from that in both DMF and a secondary protein standard. When compared with DMF, activity in serum increased but decreased relative to the protein standard as the pre-incubation interval of the assay was shortened. The use of secondary protein standards results in underestimation of serum fructosamine concentrations when the pre-incubation phase of the assay is shorter than that used for the calibration of the secondary standard. Ascorbate exerted an inhibitory effect in fructosamine assays with pre-incubation times exceeding 5 min. The inhibition increased with both the concentration of ascorbate and the duration of the pre-incubation.

scholarly journals Blue Light Perception by Both Roots and Rhizobia Inhibits Nodule Formation in Lotus japonicus

2016 ◽  
Vol 29 (10) ◽  
pp. 786-796 ◽  
Author(s):  
Aya Shimomura ◽  
Ayumi Naka ◽  
Nobuyuki Miyazaki ◽  
Sayaka Moriuchi ◽  
Susumu Arima ◽  
...  
Keyword(s):  
Blue Light ◽  
Red Light ◽  
Lotus Japonicus ◽  
Inhibitory Effect ◽  
Nodule Development ◽  
Nodule Formation ◽  
Mesorhizobium Loti ◽  
Empty Vector ◽  
Legume Nodulation ◽  
Strong Inhibitory Effect

In many legumes, roots that are exposed to light do not form nodules. Here, we report that blue light inhibits nodulation in Lotus japonicus roots inoculated with Mesorhizobium loti. Using RNA interference, we suppressed the expression of the phototropin and cryptochrome genes in L. japonicus hairy roots. Under blue light, plants transformed with an empty vector did not develop nodules, whereas plants exhibiting suppressed expression of cry1 and cry2 genes formed nodules. We also measured rhizobial growth to investigate whether the inhibition of nodulation could be caused by a reduced population of rhizobia in response to light. Although red light had no effect on rhizobial growth, blue light had a strong inhibitory effect. Rhizobial growth under blue light was partially restored in signature-tagged mutagenesis (STM) strains in which LOV-HK/PAS- and photolyase-related genes were disrupted. Moreover, when Ljcry1A and Ljcry2B-silenced plants were inoculated with the STM strains, nodulation was additively increased. Our data show that blue light receptors in both the host plant and the symbiont have a profound effect on nodule development. The exact mechanism by which these photomorphogenetic responses function in the symbiosis needs further study, but they are clearly involved in optimizing legume nodulation.

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