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61.
Limnology - The in-stream processing of nutrients plays an important role in the fluvial nutrient transport from lands to the ocean, but few empirical studies have addressed the temporal dynamics... 相似文献
62.
Kazuki Yuzuriha Ayaka Yoshida Shunyi Li Akihiro Kishimura Takeshi Mori Yoshiki Katayama 《Journal of peptide science》2020,26(10)
In this report, we designed conjugates of an antigen peptide with the immunosuppressive vitamins all‐trans retinoic acid (ATRA) and vitamin D3 for efficient induction of antigen‐specific immunotolerance. We established a synthetic scheme for the preparation of the peptide‐vitamin conjugates, which the chemically unstable vitamins tolerated. Among the obtained conjugates, the ATRA conjugate successfully suppressed inflammatory effects in macrophages and dendritic cells and induced antigen presentation in dendritic cells. This synthetic method of conjugate is conceivably applicable to other antigen peptides for induction of antigen‐specific immunotolerance. 相似文献
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Huaxin Yu Tasuku Hamaguchi Yoshiki Nakajima Koji Kato Keisuke Kawakami Fusamichi Akita Koji Yonekura Jian-Ren Shen 《BBA》2021,1862(10):148471
Photosystem II (PSII) functions mainly as a dimer to catalyze the light energy conversion and water oxidation reactions. However, monomeric PSII also exists and functions in vivo in some cases. The crystal structure of monomeric PSII has been solved at 3.6 Å resolution, but it is still not clear which factors contribute to the formation of the dimer. Here, we solved the structure of PSII monomer at a resolution of 2.78 Å using cryo-electron microscopy (cryo-EM). From our cryo-EM density map, we observed apparent differences in pigments and lipids in the monomer-monomer interface between the PSII monomer and dimer. One β-carotene and two sulfoquinovosyl diacylglycerol (SQDG) molecules are found in the monomer-monomer interface of the dimer structure but not in the present monomer structure, although some SQDG and other lipid molecules are found in the analogous region of the low-resolution crystal structure of the monomer, or cryo-EM structure of an apo-PSII monomer lacking the extrinsic proteins from Synechocystis sp. PCC 6803. In the current monomer structure, a large part of the PsbO subunit was also found to be disordered. These results indicate the importance of the β-carotene, SQDG and PsbO in formation of the PSII dimer. 相似文献
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67.
Ken Okamoto Bryan T. Eger Tomoko Nishino Emil F. Pai Takeshi Nishino 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):888-893
Inhibitors of xanthine oxidoreductase block conversion of xanthine to uric acid and are therefore potentially useful for treatment of hyperuricemia or gout. We determined the crystal structure of reduced bovine milk xanthine oxidoreductase complexed with oxipurinol at 2.0 Å resolution. Clear electron density was observed between the N2 nitrogen of oxipurinol and the molybdenum atom of the molybdopterin cofactor, indicating that oxipurinol coordinated directly to molybdenum. Oxipurinol forms hydrogen bonds with glutamate802, arginine880, and glutamate1261, which have previously been shown to be essential for the enzyme reaction. We discuss possible differences in the hypouricemic effect of inhibitors, including allopurinol and newly developed inhibitors, based on their mode of binding in the crystal structures. 相似文献
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Sachiko N. Isobe Hideki Hirakawa Shusei Sato Fumi Maeda Masami Ishikawa Toshiki Mori Yuko Yamamoto Kenta Shirasawa Mitsuhiro Kimura Masanobu Fukami Fujio Hashizume Tomoko Tsuji Shigemi Sasamoto Midori Kato Keiko Nanri Hisano Tsuruoka Chiharu Minami Chika Takahashi Tsuyuko Wada Akiko Ono Kumiko Kawashima Naomi Nakazaki Yoshie Kishida Mitsuyo Kohara Shinobu Nakayama Manabu Yamada Tsunakazu Fujishiro Akiko Watanabe Satoshi Tabata 《DNA research》2013,20(1):79-92
69.
Development of DNA markers for identifying chrysanthemum cultivars generated by ion-beam irradiation
Tsukasa Shirao Kei-ichiro Ueno Tomoko Abe Tomoki Matsuyama 《Molecular breeding : new strategies in plant improvement》2013,31(3):729-735
Four chrysanthemum cultivars were generated through (carbon) ion-beam irradiation of the original ‘Jimba’ (Chrysanthemum morifolium Ramat.). The new cultivars had acquired a number of superior cultivation traits, while remaining identical to the commercially available ‘Jimba’ in appearance. In this study, polymerase chain reaction (PCR) assays were used to detect the mutated region of each strain, thereby allowing clear identification at the molecular level. PCR assays were performed with 446 primer sets, including random amplified polymorphic DNA (RAPD) primer sets (10-mer RAPD), arbitrarily primed (AP)-PCR primers based on retrotransposon-like sequences and modified RAPD primers (15-mer RAPD). 15-mer RAPD primers generated a 1.49-fold increased band number at high annealing temperatures compared with the original 10-mer RAPD primers and could thus be effective for detection of polymorphic patterns. Our results provide information on the mutated regions of these ion-beam-irradiated chrysanthemum cultivars. Thus, specific DNA markers could be used to improve identification of new cultivars of chrysanthemum as well as other clonal cultivars of horticultural and agricultural crops. 相似文献
70.
Yumeko Hayashi Yoshiki Ishii Mitsumi Hata-Suzuki Ryo Arai Kazuyuki Chibana Akihiro Takemasa Takeshi Fukuda 《Respiratory research》2013,14(1):29