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Phytochrome photoreceptors operate via photoisomerization of a bound bilin chromophore. Their typical architecture consists of GAF, PAS and PHY domains. Knotless phytochromes lack the PAS domain, while retaining photoconversion abilities, with some being able to photoconvert with just the GAF domain. Therefore, we investigated the ultrafast photoisomerization of the P state of a knotless phytochrome to reveal the effect of the PHY domain and its "tongue" region on the transduction of the light signal. We show that the PHY domain does not affect the initial conformational dynamics of the chromophore. However, it significantly accelerates the consecutively induced reorganizational dynamics of the protein, necessary for the progression of the photoisomerization. Consequently, the PHY domain keeps the bilin and its binding pocket in a more reactive conformation, which decreases the extent of protein reorganization required for the chromophore isomerization. Thereby, less energy is lost along nonproductive reaction pathways, resulting in increased efficiency.
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http://dx.doi.org/10.1002/chem.202003138 | DOI Listing |
Light Sci Appl
August 2025
State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai, 200241, China.
Single-pixel imaging (SPI) is a promising technology for optical imaging beyond the visible spectrum, where commercial cameras are expensive or unavailable. However, limitations such as slow pattern projection rates and time-consuming reconstruction algorithms hinder its throughput for real-time imaging. Consequently, conventional SPI is inadequate for high-speed, high-resolution tasks.
View Article and Find Full Text PDFNat Commun
July 2025
State Key Laboratory of Precision Spectroscopy, Hainan Institute, East China Normal University, Shanghai, China.
Stereoscopy harnesses two spatially offset cameras to mimic human vision for depth perception, enabling 3D optical imaging for various remote sensing applications. However, its depth precision and accuracy are limited by insufficient spatial resolving power. Achieving high precision alongside extensive measurable ranges and high-speed measuring capabilities has long been a challenge in 3D imaging.
View Article and Find Full Text PDFPhotochem Photobiol Sci
August 2025
Department of Molecular and Cell Biology, University of California at Davis, One Shields Avenue, 31 Briggs Hall, Davis, CA, 95616, USA.
Phytochromes are a widespread family of red/far-red photoreceptors including master regulators of plant growth and development. Phytochromes use 15,16-photoisomerization of linear tetrapyrrole (bilin) chromophores to toggle between a 15Z red-absorbing dark-adapted state (P) and a 15E far-red-absorbing photoproduct (P). The bilin is bound within a conserved, N-terminal PAS-GAF-PHY photosensor tridomain and is covalently attached to a conserved Cys residue, but the mechanism(s) permitting detection of far-red light are not well understood.
View Article and Find Full Text PDFPediatr Obes
October 2025
Department of Biotechnology, Guru Nanak Dev University, Amritsar, India.
Background: The epidemiological and sociocultural context of Indian adolescents is rapidly changing, thus affecting their eating behaviours and increasing overweight and obesity prevalence.
Objectives: The current study was aimed at exploring associations of problematic eating behaviours and self-concept with overweight/obesity in adolescents.
Methods: This cross-sectional study was conducted in six schools in Punjab, India, and enrolled 538 randomly selected adolescents aged 10-16 years.
Entropy (Basel)
April 2025
School of Information and Communication Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China.
Physical-layer (PHY) security is widely used as an effective method for ensuring secure wireless communications. However, when the legitimate user (LU) and the eavesdropper (Eve) are in close proximity, the channel coupling can significantly degrade the secure performance of PHY. Frequency diverse array (FDA) technique addresses channel coupling issues by introducing frequency offsets among array elements.
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