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101.
Masayuki Takeguchi Takako Furuto Daisuke Sugimori Ichiro Okura 《Applied biochemistry and biotechnology》1997,68(3):143-152
Methylosinus trichosporium OB3b is a methanotrophic bacterium containing methane mono-oxygenase, catalyzing hydroxylation of methane to methanol. When
methane is oxidized, the product is subsequently oxidized by methanol dehydrogenase contained in the same bacterium. To prevent
further oxidation of methanol, the cell suspension was treated by cyclopropanol, an irreversible inhibitor for methanol dehydrogenase,
leading to extracellular methanol accumulation. However, the reaction was terminated at approx 3 h with a final methanol concentration
below 2.96 mmol/g dry cell. The methanol production efficiency (the ratio of the produced methanol per methane consumption)
was 2.90%. By selecting the culture conditions and the reaction conditions, the reaction continued for 100 h, resulting in
a methanol concentration of 152 mmol/g dry cell. This level was 51 times higher than that of the conventional reaction, and
the methanol production efficiency was 61%. 相似文献
102.
Surface dilatational moduli of poly(vinyl acetate) (PVAc) film and blend films of PVAc and poly(n-hexyl isocyanate) (PHIC) were measured at the air-water interface. PVAc formed a film that was looser and also more stable against strain than the PHIC film. The apparent surface dilatational modulus and surface pressure of the blend films were superimposed on the lower concentration of PVAc, irrespective of the composition of PVAc. However, the additivity rule was not applicable to the apparent surface dilatational modulus and surface pressure. The scaling exponents of the apparent surface dilatational modulus against the added surface concentration decreased with an increase in the proportion of PVAc, suggesting that blend films gradually change from glass material to expanded films. 相似文献
103.
Ishikawa K Yamamoto T Takagi Y 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2006,179(2):234-240
We measured the spin relaxation of polarized xenon atoms dissolved in deuterated ethanol. Surface relaxation was suppressed by coating the cell walls with deuterated eicosane. From the dependence of the decay rate on temperature and static magnetic field, we obtained the correlation time of random fluctuations of the local field at the liquid-solid interface. By varying the cell volume, the wall coating, and the surface area of the eicosane, we measured the contribution of the spin-rotation interaction to the relaxation. The use of both deuterated molecules enables us to distinguish surface relaxation from the magnetic dipole-dipole and spin-rotation interactions in solution. 相似文献
104.
Saito H Honma T Minamisawa T Yamazaki K Noda T Yamori T Shiba K 《Chemistry & biology》2004,11(6):765-773
Here, we describe a synthetic approach for generating artificial proteins by the assemblage of naturally occurring peptide motifs. Two motifs respectively related to apoptosis induction and protein transduction were encrypted into different reading frames of an artificial gene (microgene), which was then polymerized; random frame shifts at the junctions between the microgene units yielded combinatorial polymers of three reading frames. Among the proteins created, #284 was found to penetrate through cell membranes and exert a strong apoptotic effect on several cancer cell lines. Because a simple linkage of these motifs was not sufficient to construct a bifunctional peptide, and the successful reconstitution was dependent on how they were joined together, the combinatorial strategy is important for reconstituting functions from mixtures of motifs. This microgene-based approach represents a novel system for creating proteins with desired functions. 相似文献
105.
Ohne ZusammenfassungHerrn ProfessorGottfried Köthe zum 60. Geburtstag am 25. Dezember 1965 gewidmet 相似文献
106.
Norio Kawahara Takako Shimamori Tsuneo Itoh Hiroaki Takayanagi Haruo Ogura 《Journal of heterocyclic chemistry》1989,26(3):847-852
1-Hydroxyphenyl-2-pyridone derivatives 8, 10 and 11 were easily prepared by treatment of methyl isocro-tonate derivatives 6 with base at room temperature in good yields. 相似文献
107.
108.
Taishi Uchida Dr. Yasunobu Egawa Takuto Adachi Naoki Oguri Masato Kobayashi Prof. Dr. Takako Kudo Prof. Dr. Nobuhiro Takeda Prof. Dr. Masafumi Unno Dr. Ryoji Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(7):1683-1686
Symmetric and asymmetric (Janus-type) new “lantern cage” siloxanes (PhSiO1.5)4(Me2SiO)4(RSiO1.5)4 (R=Ph or iBu) were synthesized through reaction of all-cis-[PhSi(OSiMe2Br)O]4 with all-cis-[RSi(OH)O]4 (R=Ph or iBu). These precursors were obtained by facile two or three-step reactions from commercially available compounds. The spectroscopic properties of the resulting products were fully characterized and they showed high thermal stability and sublimation without decomposition. The crystal structures clearly indicated that the internal vacancy volumes of the lantern cages are considerably larger than that of octaphenylsilsesquioxane (PhSiO1.5)8. DFT calculations of the lantern cage showed a distinctly different electronic state from that of octasilsesquioxane. These results suggest that lantern cage siloxanes have a characteristic “field” in the molecule. 相似文献
109.
Seiya Yoshida Takuma Suzuki Hiroshi Furuno Takako Aboshi Tetsuya Murayama Takuya Koseki 《Natural product research》2018,32(1):60-64
Two new polyketides, (5R,7R,9R)-7,9-dihydroxy-5-decanolide and (4E,6R,9R)- 6,9-dihydroxydec-4-enoic acid (2), were isolated from rice cultures of Cylindrocarpon sp. SY-39 discovered during screening of driftwood at a Shonai coast area in Yamagata, Japan. The structures of 1 and 2 were determined using a variety of spectroscopic methods. Compound 2 exhibited moderate antimicrobial activity against Staphylococcus aureus NBRC 13276 and Aspergillus clavatus F 318a at a concentration of 50 μg per disk. 相似文献
110.
Dr. Mari Toyama Takako Takizawa Itaru Morita Prof. Noriharu Nagao Dr. Yusuke Kuramochi Prof. Hitoshi Ishida 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(72):16582-16590
Two isomers of heteroleptic bis(bidentate) ruthenium(II) complexes with dimethyl sulfoxide (dmso) and chloride ligands, trans(Cl,Nbpy)- and trans(Cl,NHdpa)-[Ru(bpy)Cl(dmso-S)(Hdpa)]+ (bpy: 2,2′-bipyridine; Hdpa: di-2-pyridylamine), are synthesized. This is the first report on the selective synthesis of a pair of isomers of cis-[Ru(L)(L′)XY]n+ (L≠L′: bidentate ligands; X≠Y: monodentate ligands). The structures of the ruthenium(II) complexes are clarified by means of X-ray crystallography, and the signals in the 1H NMR spectra are assigned based on 1H–1H COSY spectra. The colors of the two isomers are clearly different in both the solid state and solution: the trans(Cl,Nbpy) isomer has a deep red color, whereas the trans(Cl,NHdpa) isomer is yellow. Although both complexes have intense absorption bands at λ≈440–450 nm, only the trans(Cl,Nbpy) isomer has a shoulder band at λ≈550 nm. DFT calculations indicate that the LUMOs of both isomers are the π* orbitals in the bpy ligand, and that the LUMO level of the trans(Cl,Nbpy) isomer is lower than that of the trans(Cl,NHdpa) isomer due to the trans effect of the Cl ligand; thus resulting in the appearance of the shoulder band. The HOMO levels are almost the same in both isomers. The energy levels are experimentally supported by cyclic voltammograms, in which these isomers have different reduction potentials and similar oxidation potentials. 相似文献