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91.
Takaaki Kubota Yuichiro Ishiguro Azusa Takahashi-Nakaguchi Jane Fromont Tohru Gonoi Jun’ichi Kobayashi 《Bioorganic & medicinal chemistry letters》2013,23(1):244-247
Three new polyketides, manzamenones L–N (1–3), have been isolated from an Okinawan marine sponge of the genus Plakortis. The structures of 1–3 were elucidated on the basis of spectroscopic data. Manzamenones L–N (1–3) were new dimeric fatty-acid derivatives consisting of a tetrahydroindenone with three carboxy groups and two hexadecanyl chains. Manzamenones M (2) and N (3) showed antimicrobial activity against several bacteria and fungi. 相似文献
92.
Yohei Takahashi Takaaki Kubota Sunao Yamamoto Jun’ichi Kobayashi 《Bioorganic & medicinal chemistry letters》2013,23(1):117-118
Metachromins are a series of sesquiterpenoid quinones isolated from Okinawan marine sponges. Inhibitory effects of metachromins L–Q (1–6), sesquiterpenoid quinones with an amino acid residue, and their related analogs (7–18) prepared from metachromins A (19) and C (20) against receptor tyrosine kinases EGFR and HER2 were investigated. Two analogs 11 and 12 showed relatively stronger inhibitory activity against EGFR, while metachromins L–Q (1-6) and seven analogs (8, 10, 11, and 15–18) showed inhibitory activities against HER2. 相似文献
93.
Yoshiro Kinoshita Michinori Misaka Shuhei Kubota Hisao Ishikawa 《Bioscience, biotechnology, and biochemistry》2013,77(11):1975-1981
A mixture of two thionocarbamates was subjected to the acid-catalyzed rearrangement. A sample of the reaction mixture was analyzed by glpc and resolved into four components. From the cross-over result, it has been concluded that the acid-catalyzed rearrangement of alkyl thionocarbamates into the isomeric thiolcarbamates proceeds by an intermolecular alkylating mechanism. This conclusion was supported by the detection of a transalkylated intermediate. 相似文献
94.
Tomoya Ogawa Motoshi Yasui Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(8):1445-1447
The Colletotrichum lagenarium PKS1 gene was expressed in the heterologous fungal host, Aspergillus oryzae, under the starch-inducible α-amylase promoter to identify the direct product of polyketide synthase (PKS) encoded by the PKS1 gene. The main compound produced by an A. oryzae transformant was isolated and characterized to be 1,3,6,8-tetrahydroxynaphthalene (T4HN) as its tetraacetate. Since the PKS1 gene was cloned from C. lagenarium to complement the nonmelanizing albino mutant, T4HN was assumed to be an initial biosynthetic intermediate, and thus the product of the PKS reaction, but had not been isolated from the fungus. The production of T4HN by the PKS1 transformant unambiguously identified the gene to encode a PKS of pentaketide T4HN. In addition, tetraketide orsellinic acid and pentaketide isocoumarin were isolated, the latter being derived from a pentaketide monocyclic carboxylic acid, as by-products of the PKS1 PKS reaction. Production of the pentaketide carboxylic acid provided insights into the mechanism for the PKS1 polyketide synthase reaction to form T4HN. 相似文献
95.
96.
Fumio Sugawara Haruhiko Nakayama Gary A. Strobel Tomoya Ogawa 《Bioscience, biotechnology, and biochemistry》2013,77(9):2261-2271
The stereoselective synthesis of 1- and 2-O-α-d-cellotriosyl-3-deoxy-2(R)- and 2(S)-glycerols, which determined the structure of rhynchosporoside produced by Rhynchosporium secalis, and their phytotoxicity toward the host plant (Hordeum vulgare) are described in detail. 相似文献
97.
Kenji Kano Tomonori Konse Motoko Okada Tanekazu Kubota Sachiko Ibe Tokuji Ikeda 《Bioscience, biotechnology, and biochemistry》2013,77(7):1795-1800
A polarographic method based on the Brdi?ka current (the polarographic catalytic hydrogen evolution current produced by proteins in the presence of cobalt salts) was applied to direct titration of subtilisin BPN′ (S.BPIST) with plasminostreptin (PS) at a concentration level of 10”8 m. The first and second dissociation constants of the S.BPN-PS complex were determined by fitting theoretical curves to the titration data, in which the multiple equilibria involving microscopically distinct forms of S.BPN-PS complex were taken into account. The intrinsic free energy change in the first binding of S.BPN′ to dimeric PS was larger than that in the second binding. The dependence of the microscopic dissociation constants of S.BPN′-PS complex on pH indicates the participation of ionizable groups of pKa 8.0 and 9.4 in the complex formation. The repulsive effect between negatively charged molecules of S.BPN′ and PS in the complex formation at elevated pH is suggested. 相似文献
98.
Kenji Kobata Ikue Takemura Gaku Tago Takayuki Moriya Kaori Kubota Sachie Nakatani 《Bioscience, biotechnology, and biochemistry》2013,77(7):1242-1245
Long-chain N-vanillyl-acylamides (LCNVAs) were generated from plant oils and vanillylamine (VA) by nucleophilic amidation without any catalytic reagents. The resulting LCNVAs varied according to the fatty acid composition of the plant oil used. Therefore, the LCNVAs contained in Capsicum oleoresins were products that were spontaneously generated from the oleoresin during storage. 相似文献
99.
Hirofumi Sakoguchi Tomoya Shintani Hironobu Ishiyama Ryo C. Yanagita Yasuhiro Kawanami 《Bioscience, biotechnology, and biochemistry》2013,77(12):2194-2197
ABSTRACTThe nematocidal activities of the fatty acid esters of d-allose were examined using the larvae of C. elegans. Among the fatty acid esters, 6-O-octanoyl-d-allose (3) showed significant activity. 6-O-octanoyl-d-glucose (5) showed no activity, indicating that the D-allose moiety is essential for the nematocidal activity of 3. A nonhydrolyzable alkoxy analog 6-O-octyl-d-allose (6) also showed activity equivalent to that of 3. 相似文献
100.
Taku Fukuzawa Junji Ishida Akira Kato Taro Ichinose Donna Maretta Ariestanti Tomoya Takahashi Kunitoshi Ito Jumpei Abe Tomohiro Suzuki Shigeharu Wakana Akiyoshi Fukamizu Nobuhiro Nakamura Shigehisa Hirose 《PloS one》2013,8(7)
Lung surfactant is a complex mixture of lipids and proteins, which is secreted from the alveolar type II epithelial cell and coats the surface of alveoli as a thin layer. It plays a crucial role in the prevention of alveolar collapse through its ability to reduce surface tension. Under normal conditions, surfactant homeostasis is maintained by balancing its release and the uptake by the type II cell for recycling and the internalization by alveolar macrophages for degradation. Little is known about how the surfactant pool is monitored and regulated. Here we show, by an analysis of gene-targeted mice exhibiting massive accumulation of surfactant, that Ig-Hepta/GPR116, an orphan receptor, is expressed on the type II cell and sensing the amount of surfactant by monitoring one of its protein components, surfactant protein D, and its deletion results in a pulmonary alveolar proteinosis and emphysema-like pathology. By a coexpression experiment with Sp-D and the extracellular region of Ig-Hepta/GPR116 followed by immunoprecipitation, we identified Sp-D as the ligand of Ig-Hepta/GPR116. Analyses of surfactant metabolism in Ig-Hepta+/+ and Ig-Hepta−/− mice by using radioactive tracers indicated that the Ig-Hepta/GPR116 signaling system exerts attenuating effects on (i) balanced synthesis of surfactant lipids and proteins and (ii) surfactant secretion, and (iii) a stimulating effect on recycling (uptake) in response to elevated levels of Sp-D in alveolar space. 相似文献