著者

Susumu Yoshizawa Tomonori Azuma Keiichi Kojima Keisuke Inomura Masumi Hasegawa Yosuke Nishimura Masuzu Kikuchi Gabrielle Armin Yuya Tsukamoto Hideaki Miyashita Kentaro Ifuku Takashi Yamano Adrian Marchetti Hideya Fukuzawa Yuki Sudo Ryoma Kamikawa

出版者

Japanese Society of Microbial Ecology / Japanese Society of Soil Microbiology / Taiwan Society of Microbial Ecology / Japanese Society of Plant Microbe Interactions / Japanese Society for Extremophiles

雑誌

Microbes and Environments (ISSN:13426311)

巻号頁・発行日

vol.38, no.2, pp.ME23015, 2023 (Released:2023-06-20)

参考文献数

46

被引用文献数

4

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Diatoms are a major phytoplankton group responsible for approximately 20% of carbon fixation on Earth. They perform photosynthesis using light-harvesting chlo­rophylls located in plastids, an organelle obtained through eukaryote-eukaryote endosymbiosis. Microbial rhodopsin, a photoreceptor distinct from chlo­rophyll-based photosystems, was recently identified in some diatoms. However, the physiological function of diatom rhodopsin remains unclear. Heterologous expression techniques were herein used to investigate the protein function and subcellular localization of diatom rhodopsin. We demonstrated that diatom rhodopsin acts as a light-driven proton pump and localizes primarily to the outermost membrane of four membrane-bound complex plastids. Using model simulations, we also examined the effects of pH changes inside the plastid due to rhodopsin-mediated proton transport on photosynthesis. The results obtained suggested the involvement of rhodopsin-mediated local pH changes in a photosynthetic CO2-concentrating mechanism in rhodopsin-possessing diatoms.

著者

Takashi Yamano Takashi Kubo Yasutsugu Shiono Kunihiro Shimamura Makoto Orii Takashi Tanimoto Yoshiki Matsuo Yasushi Ino Hironori Kitabata Tomoyuki Yamaguchi Kumiko Hirata Atsushi Tanaka Toshio Imanishi Takashi Akasaka

出版者

一般社団法人 日本動脈硬化学会

雑誌

Journal of Atherosclerosis and Thrombosis (ISSN:13403478)

巻号頁・発行日

pp.25593, (Released:2014-08-15)

参考文献数

22

被引用文献数

6 33

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Aim: Previous clinical trials have demonstrated the effectiveness of eicosapentaenoic acid (EPA) in preventing cardiovascular events. The aim of the present study was to investigate the effects of EPA treatment on the accumulation of coronary atherosclerotic plaque using optical coherence tomography (OCT). Methods: A total of 46 acute coronary syndrome (ACS) patients without dyslipidemia were divided into two groups: those who received 1,800 mg/day of EPA (n=15) or the control group (n=31). Serial OCT examinations were performed at baseline and after eight months of follow-up. The target for the OCT analysis was non-culprit plaque with a percent diameter of stenosis of 30% to 70% in non-culprit vessels of ACS. Results: Between the baseline and follow-up visits, the serum EPA levels increased (50±26 mg/dL to 200±41 mg/dL, p<0.001) in the EPA group, although they did not change in the control group. According to the OCT analysis, the lipid arc did not change in the EPA group (131±52 degrees to 126±54 degrees, p=0.106) or the control group (137±50 degrees to 138±50 degrees, p=0.603). In contrast, the fibrous cap thickness significantly increased in both the EPA group (169±70 μm to 201±49 μm, p<0.001) and the control group (164±63 μm to 174±72 μm, p=0.018); however, the relative change in the fibrous cap thickness was significantly greater in the EPA group than in the control group (131±35% vs. 106±15%, p=0.001). Conclusions: In the present study, the administration of EPA for eight months significantly increased the fibrous cap thickness in patients with coronary atherosclerotic plaque.