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81.
Emiko Kinoshita‐Kikuta Hiroshi Kusamoto Syogo Ono Keisuke Akayama Yoko Eguchi Masayuki Igarashi Toshihide Okajima Ryutaro Utsumi Eiji Kinoshita Tohru Koike 《Electrophoresis》2019,40(22):3005-3013
In the bacterial signaling mechanisms known as two‐component systems (TCSs), signals are generally conveyed by means of a His–Asp phosphorelay. Each system consists of a histidine kinase (HK) and its cognate response regulator. Because of the labile nature of phosphorylated His and Asp residues, few approaches are available that permit a quantitative analysis of their phosphorylation status. Here, we show that the Phos‐tag dye technology is suitable for the fluorescent detection of His‐ and Asp‐phosphorylated proteins separated by SDS‐PAGE. The dynamics of the His–Asp phosphorelay of recombinant EnvZ‐OmpR, a TCS derived from Escherichia coli, were examined by SDS‐PAGE followed by simple rapid staining with Phos‐tag Magenta fluorescent dye. The technique permitted not only the quantitative monitoring of the autophosphorylation reactions of EnvZ and OmpR in the presence of adenosine triphosphate (ATP) or acetyl phosphate, respectively, but also that of the phosphotransfer reaction from EnvZ to OmpR, which occurs within 1 min in the presence of ATP. Furthermore, we demonstrate profiling of waldiomycin, an HK inhibitor, by using the Phos‐tag Cyan gel staining. We believe that the Phos‐tag dye technology provides a simple and convenient fluorometric approach for screening of HK inhibitors that have potential as new antimicrobial agents. 相似文献
82.
Toshihide Baba Yuki Morikawa Norito Komatsu Toshiro Takahashi Hisashi Sugisawa Yoshio Ono 《Research on Chemical Intermediates》2000,26(1):13-20
The dynamic properties of protons in H-[Ga]-ZSM-5, H-[B]-ZSM-5 and H-[Al-B]-ZSM-5 were compared with that of protons in H-[Al]-ZSM-5
by temperature dependence of 1H MAS NMR in the range of 298 k and 473 K. The temperature dependence of the line width of 1H MAS NMR reveals that protons in H-[Ga]-ZSM-5 were more mobile than those in H-[Al]-ZSM-5 at temperature as low as 373 K.
The protons in H-[B]-ZSM-5 were not mobile at 473 K and fixed in the zeolite frame work as the bridging hydroxyl groups, ≡B-OH-Si≡.
The thermal motion of protons in ≡Al-OH-Si≡ was suppressed by introducing B3+ cations into the framework of H-[Al]-ZSM-5. 相似文献
83.
84.
57Fe Mössbauer spectroscopic studies on the β-Fe1.12Te, δ′-Fe1.33Te2 and ε-FeTe2.11 samples have been performed in the temperature range from room temperature to 1000K. The isomer shifts of β-Fe1.12Te, δ′-Fe1.33Te2 and ε-FeTe2.11 samples at 823K are 0.09, 0.18 and 0.17 mm/s, respectively. The smaller isomer shift of β-phase with iron in tetrahedral sites than those of δ′- and ε-phases with iron in octahedral sites may be explained probably due to small shielding by d-electrons. The effects of temperature and composition on the isomer shift and quadrupole splitting are discussed. 相似文献
85.
Kazuhisa Makino Toshihide Ibaraki 《Journal of Algorithms in Cognition, Informatics and Logic》1998,26(2):291-305
Consider the problem of identifying min T(f) and max F(f) of a positive (i.e., monotone) Boolean functionf, by using membership queries only, where min T(f) (max F(f)) denotes the set of minimal true vectors (maximum false vectors) off. Moreover, as the existence of a polynomial total time algorithm (i.e., polynomial time in the length of input and output) for this problem is still open, we consider here a restricted problem: given an unknown positive functionfofnvariables, decide whetherfis 2-monotonic or not, and iffis 2-monotonic, output both min T(f) and max F(f). For this problem, we propose a simple algorithm, which is based on the concept of maximum latency, and we show that it usesO(n2m) time andO(n2m) queries, wherem = |min T(f)| + |max F(f)|. This answers affirmatively the conjecture raised in Boroset al.[Lecture Notes in Comput. Sci.557(1991), 104–115], Boroset al.[SIAM J. Comput.26(1997), 93–109], and is an improvement over the two algorithms discussed therein: one usesO(n3m) time andO(n3m) queries, and the other usesO(nm2 + n2m) time andO(nm) queries. 相似文献
86.
T. Takagahara 《Solid State Communications》1981,38(3):179-182
A nonlinear optical method to determine the transverse relaxation time of excitonic molecules by means of two-photon echo is proposed. In the case of two-photon transition such as excitonic molecule one needs three pulses to obtain an echo signal. When the wave-vector and frequency of the three successive pulses are denoted by k1,ω1, k2,ω2 and k3,ω3, the two-photon echo can be observed in the direction of 4k2-2k1-k3 with frequency 4ω2-2ω1-ω3. Tuning both ω1 and ω2 to be two-photon resonant with excitonic molecule, we can satisfy the phase-matching condition rather easily for appropriate values of ω3 due to the large dispersion of excitonic polaritons. From the correlation trace of the two-photon echo we can determine directly the transverse relaxation time of excitonic molecules. 相似文献
87.
Nozaki K Li Wg Horiuchi T Takaya H Saito T Yoshida A Matsumura K Kato Y Imai T Miura T Kumobayashi H 《The Journal of organic chemistry》1996,61(22):7658-7659
88.
Toshihide Ibaraki 《Mathematical Programming》1983,26(3):345-362
The fractional program P is defined by maxf(x)/g(x) subject tox∈X. A class of methods for solving P is based on the auxiliary problem Q(λ) with a parameter λ: maxf(x)?λg(x) subject tox∈X. Starting with two classical methods in this class, the Newton method and the binary search method, a number of variations are introduced and compared. Among the proposed methods. the modified binary search method is theoretically interesting because of its superlinear convergence and the capability to provide an explicit interval containing the optimum parameter value \(\bar \lambda \) . Computational behavior is tested by solving fractional knapsack problems and quadratic fractional programs. The interpolated binary search method seems to be most efficient, while other methods also behave surprisingly well. 相似文献
89.
Zhan Jie Wang Hirokazu Usuki Toshihide Kumagai Hiroyuki Kokawa 《Journal of Sol-Gel Science and Technology》2007,42(3):375-379
(La0.7Sr0.3)MnO3 thin films were deposited on SiO2/Si substrates by a metal-organic decomposition (MOD) method, and then Pb(Zr0.52Ti0.48)O3 (PZT) thin films were grown on (La0.7Sr0.3)MnO3-coated SiO2/Si substrates by a sol-gel method. The effects of annealing temperature on the crystalline phases, microstructures and electrical
properties of the PZT films were investigated. X-ray diffraction analysis results indicated that the PZT films with a perovskite
single phase could be obtained by annealing at 650°C. The dielectric constant and the remnant polarization of the PZT films
increased with increasing annealing temperature. The remnant polarization and the coercive field of the films annealed at
650°C were 18.3 μC/cm2 and 35.5 kV/cm, respectively, whereas the dielectric constant and loss value measured at 1 kHz were approximately 1100 and
0.81, respectively. 相似文献
90.
Toshihide Kawanaka 《Tetrahedron letters》2007,48(11):1973-1976
Oligodeoxyribonucleotides and their backbone-modified analogs were synthesized in good yields by the boranophosphotriester method in solution. The oligodeoxyriobonucleoside boranophosphates, fully protected with 2-(azidomethyl)benzoyl groups, were converted to the various backbone-modified DNA analogs via the corresponding H-phosphonate intermediates. A new efficient protecting group for the O6-position of 2′-deoxyguanosine, 4-[(2-azidomethyl)benzoyloxy]benzyl (AZBn) group, was also developed. The AZBn group was found to be quickly removed by treatment with MePPh2 in dioxane-2-mercaptoethanol-H2O. 相似文献