Photosynthetic light-harvesting apparatus efficiently capture sunlight and transfer the energy to reaction centers, while they safely dissipate excess energy to surrounding environments for a protection of their organisms. In this study, we performed pump-probe spectroscopic measurements with a temporal window ranging from femtosecond to submillisecond on the purple bacterial antenna complex LH2 from Rhodobacter sphaeroides 2.4.1 to clarify its photoprotection functions. The observed excited state dynamics in the time range from subnanosecond to microsecond exhibits that the triplet-triplet excitation energy transfer from bacteriochlorophyll a to carotenoid takes place with a time constant of 16.7 ns. Furthermore, ultrafast spectroscopic data suggests that a molecular assembly of bacteriochlorophyll a in LH2 efficiently suppresses a generation of triple bacteriochlorophyll a.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.jpcb.6b00121 | DOI Listing |
Nitric Oxide
December 2024
Key Laboratory for Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100191, China. Electronic address:
Background: Osteocytes are crucial for detecting mechanical stimuli and translating them into biochemical responses within the bone. The primary cilium, a cellular 'antenna,' plays a vital role in this process. However, there is a lack of direct correlation between cilium length changes and osteocyte mechanosensitivity changes.
View Article and Find Full Text PDFFEMS Microbiol Lett
December 2024
K.A. Timiryazev Institute of Plant Physiology of the Russian Academy of Sciences, Botanicheskaya St. 35, Moscow 127276, Russian Federation.
A new filamentous phototrophic bacterium Khr17 was isolated as an enrichment culture from the brackish polar lake Bol'shie Khruslomeny. The organism was a halotolerant, strictly anaerobic phototroph possessing photosystem II. Sulfide was required for phototrophic growth.
View Article and Find Full Text PDFWater Res
December 2024
School of Chemistry and Environment, Guangdong Ocean University, Zhanjiang, 524088, China; Analyzing and Testing Center, Guangdong Ocean University, Zhanjiang, 524088, China; Analytical and Testing Center for Ocean in Western of Guangdong Province, Guangdong Provincial Observation and Research Station for Tropical Ocean Environment in Western Coastal Water, Guangdong Ocean University, Zhanjiang, 524088, China. Electronic address:
Corals are representative of typical symbiotic organisms. The coral-algal (Symbiodinium spp.) symbiosis drives the productivity of entire coral reefs.
View Article and Find Full Text PDFAdv Mater
December 2024
Advanced Microscopy and Instrumentation Research Center, Harbin Institute of Technology, Harbin, 150080, P. R. China.
Nowadays, metasurfaces have attracted considerable attention due to their promising and advanced control of electromagnetic (EM) waves. However, it is still challenging to shape guided waves into desired free-space mode, while simultaneously manipulating spatial incident waves using a single metasurface. Herein, a class of metasurfaces capable of multiplexing guided and space waves is proposed to achieve advanced EM functionalities in microwave regions, which can find great application potentials in radar systems, wireless communications, and wireless power transfer (WPT).
View Article and Find Full Text PDFCommun Biol
December 2024
Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
Purple phototrophic bacteria produce two kinds of light-harvesting complexes that function to capture and transmit solar energy: the core antenna (LH1) and the peripheral antenna (LH2). The apoproteins of these antennas, encoded respectively by the genes pufBA and pucBA within and outside the photosynthetic gene cluster, respectively, exhibit conserved amino acid sequences and structural topologies suggesting they were derived from a shared ancestor. Here we present the structures of two photosynthetic complexes from Roseospirillum (Rss.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!