The purpose of this study was to find flavin derivatives with absorption maxima in the blue-green region of the visible spectrum that might be used as alternative cofactors in blue-light photoreceptors. To this end, the vertical absorption spectra of eight lumiflavin-related compounds were calculated by means of quantum chemical methods. The compounds differ from lumiflavin by the subsitution o...

The pathogenesis of age-related maculopathy (ARM), the most common cause of visual loss after the age of 60 years, is indeed a complicated scenario that involves a variety of hereditary and environmental factors. The pathological cellular and molecular events underlying retinal photochemical light damage, including photoreceptor apoptosis, have been analysed in experimental animal models. Studi...

Targeting the photosensitive ion channel channelrhodopsin-2 (ChR2) to the retinal circuitry downstream of photoreceptors holds promise in treating vision loss caused by retinal degeneration. However, the high intensity of blue light necessary to activate channelrhodopsin-2 exceeds the safety threshold of retinal illumination because of its strong potential to induce photochemical damage. In con...

Phototropins are autophosphorylating protein kinases of plant-specific blue light receptors. They regulate various blue light responses, including phototropism, chloroplast movements, hypocotyl growth inhibition, leaf flattening, and stomatal opening. However, the physiological role of autophosphorylation remains unknown. Here, we identified phosphorylation sites of Ser or Thr in the N terminus...

The objective of the present study was to test the hypothesis that the acclimation to different light intensities in the diatom Phaeodactylum tricornutum is controlled by light quality perception mechanisms. Therefore, semi-continuous cultures of P. tricornutum were illuminated with equal amounts of photosynthetically absorbed radiation of blue (BL), white (WL), and red light (RL) and in combin...

Recently much attention has been paid by horticulturists to light-emitting diodes as a new source of economical and spectral-selective light. The reason is mainly coming from their versatility in handling and mounting, long working time, wattage use efficiency and lower heat production. In this study we examined their potential in promoting seed germination and producing quality flower seedling...

A pigment different from (Z,Z)bilirubin-IX alpha was detected by fluorometric methods in blood specimens from newborn infants undergoing blue-light therapy for unconjugated hyperbilirubinemia; it was not detected in specimens from infants not under therapy. The phototherapy-associated pigment has fluorescence, solubility, and photochemical properties that are identical to those exhibited by wha...

For over 100 years it has been known that a blue light photoreceptor regulates growth and development in plants under low-light conditions. These photoreceptors were termed cryptochomes (CRYs) because of their importance in cryptogamic plants and the cryptic aspects of their function and photochemistry (1, 2). Despite decades of progress into their structure and photochemistry (discussed below)...

Multi-wavelength chlorophyll fluorescence analysis was utilised to examine the photosynthetic efficiency of the biofuel-producing alga Nannochloropsis oculata, grown under two light regimes; low (LL) and high (HL) irradiance levels. Wavelength dependency was evident in the functional absorption cross-section of Photosystem II (σII(λ)), absolute electron transfer rates (ETR(II)), and non-photoch...