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121.
High-Quality Protein Crystal Growth of Mouse Lipocalin-Type Prostaglandin D Synthase in Microgravity
Inaka K Takahashi S Aritake K Tsurumura T Furubayashi N Yan B Hirota E Sano S Sato M Kobayashi T Yoshimura Y Tanaka H Urade Y 《Crystal growth & design》2011,11(6):2107-2111
Lipocalin-type prostaglandin (PG) D synthase (L-PGDS) catalyzes the isomerization of PGH(2) to PGD(2) and is involved in the regulation of pain and of nonrapid eye movement sleep and the differentiation of male genital organs and adipocytes, etc. L-PGDS is secreted into various body fluids and binds various lipophilic compounds with high affinities, acting also as an extracellular transporter. Mouse L-PGDS with a C65A mutation was previously crystallized with citrate or malonate as a precipitant, and the X-ray crystallographic structure was determined at 2.0 ? resolution. To obtain high-quality crystals, we tried, unsuccessfully, to crystallize the C65A mutant in microgravity under the same conditions used in the previous study. After further purifying the protein and changing the precipitant to polyethylene glycol (PEG) 8000, high-quality crystals were grown in microgravity. The precipitant solution was 40% (w/v) PEG 8000, 100 mM sodium chloride, and 100 mM HEPES-NaOH (pH 7.0). Crystals grew on board the International Space Station for 11 weeks in 2007, yielding single crystals of the wild-type L-PGDS and the C65A mutant, both of which diffracted at around 1.0 ? resolution. The crystal quality was markedly improved through the use of a high-viscosity precipitant solution in microgravity, in combination with the use of a highly purified protein. 相似文献
122.
Yoshinori KasaiChika Sakamoto Naoki MuroyaShin-ichiro Kato Yosuke Nakamura 《Tetrahedron letters》2011,52(5):623-625
[2]Rotaxanes, consisting of a fullerene derivative bearing an electron-donating 1,5-dialkoxynaphthalene moiety and a macrocycle containing electron-deficient naphthalenetetracarboxylic diimide moieties, were first successfully synthesized and characterized. 相似文献
123.
124.
Two diterpenoids, (+)-labda-7,14-dien-13-ol and (+)-manoyl oxide, and one bis(bibenzyl) compound, isomarchantin C, were isolated as the major components from the Taiwanese liverwort Mylia nuda. The spectral evidence is discussed in this paper. In addition, several monoterpenes and sesquiterpenes were also identified by GC/MS. 相似文献
125.
126.
Yoshinori Nagahama 《Zeitschrift fur Physik C Particles and Fields》1986,31(4):583-590
We consider the 2+1 dimensional massive QED and discuss the induced topological term in the one-loop level by using the higher derivative regularization. We show that the higher derivative regularization, which manifestly preserves the parity invariance when the fermion mass vanishes, automatically leads to a nonvanishing topological term in low energies. Although this higher derivative regularization formally violates the local gauge invariance, we propose a systematic way to recover the gauge invariance by adding local counter terms dictated by Ward-Takahashi identities. In practical applications, this regularization is interesting in connection with the discussion of the dynamical origin of the quantum Hall effect. 相似文献
127.
Akio Tsuboi Petr Kol Takeshi Ishikawa Yoshinori Kamiya Hirokatsu Masuoka 《Journal of Polymer Science.Polymer Physics》2001,39(12):1255-1262
The sorption of C2 and C3 hydrocarbons in two ethylene–propylene copolymers and a propylene homopolymer and the simultaneous dilation of the polymers were measured at temperatures of 287–363 K and pressures up to 4 MPa. The sorption isotherms were well described by the Flory–Huggins theory of dissolution. Dilation isotherms in the form of elongation versus pressure were similar in shape to the corresponding sorption isotherms. Solubility coefficients, partial molar volumes, and Flory–Huggins interaction parameters were determined from these isotherms. The thermal expansivities of the hydrocarbons dissolved in the polymers were 0.002–0.005 K?1, and the Flory–Huggins interaction parameters depended not only on temperature but also on concentration. At 323 K, the calculated solubilities of propylene in the ethylene–propylene‐rubber regions of the copolymers were 1.8 times higher than in the amorphous regions of the propylene homopolymer. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1255–1262, 2001 相似文献
128.
Hiroaki Miyaoka Yoshinori Hara Ikuo Shinohara Takao Kurokawa Yasuji Yamada 《Tetrahedron letters》2005,46(46):7945-7949
Synthesis of the marine eicosanoid agardhilactone has been achieved. The relative and absolute configuration of agardhilactone was successfully determined. 相似文献
129.
Shin-ichiro Fujita Shuhei Moribe Yoshinori Kanamori Nobutsune Takezawa 《Reaction Kinetics and Catalysis Letters》2000,70(1):11-16
The CuO crystallite size of the catalysts obtained from aurichalcite greatly depends on the heating rate of calcination for highly active and selective Cu/ZnO catalyst was prepared by reduction with methanol at 443 K for 17 h. 相似文献
130.
Yoshinori Kamiya Keishin Mizoguchi Yasutoshi Naito Takuji Hirose 《Journal of Polymer Science.Polymer Physics》1986,24(3):535-547
High-pressure sorption (up to 50 atm) for CO2, N2, and Ar in poly(vinyl benzoate) (PVB) was studied at temperatures from 25 to 70°C by a gravimetric method utilizing an electromicrobalance. The results are described by Henry's law above the glass transition temperature Tg for all gases. The dual-mode sorption model, Henry's law plus a Langmuir isotherm, applies to the sorption isotherms of N2 and Ar in the glassy state, and the dual-mode parameters are given. For CO2, a new type of sorption isotherm is observed below Tg. The isotherm is concave to the pressure axis in the low-pressure region and turns into a straight line with increasing CO2 pressure which can be extrapolated back to the coordinate origin. The linear part of the isotherm is characteristic of the rubbery state, while the nonlinear part stems from glassystate behavior. The “glass transition solubility” of CO2, at which PVB film changes from the glassy to the rubbery state, decrease as the temperature increases. The disappearance of microvoids, that is, the decrease of the Langmuir capacity, may be due to a large plasticizing effect of sorbed CO2. The difference between the N2 and Ar isotherms and the CO2 isotherm is discussed from this standpoint. 相似文献