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Three hen egg-white lysozyme inhibitor producing strains, Enterobacter cloacae M-1002, E. sakazakii M-1204, and Erwinia rhapontici H-55, were isolated from the soils of Taiwan. E. cloacae M-1002 appeared to be a promising inhibitor producing strain. One inhibitor was isolated from the culture broth of this strain. Maximum lysozyme inhibitory activity was obtained when the bacterium was grown aerobically in a medium consisting of 0.75% glucose, 0.25% beef extract, 1.0% polypeptone, and 0.25% sodium L-glutamate (pH 70) at 37 °C after 36–48 hrs. A hen egg-white lysozyme inhibitor was isolated from the culture broth of this strain. The inhibitor was purified from the culture supernatant of E. cloacae M-1002 by ammonium sulfate fractionation, DEAE-Sepharose CL-6B column chromatography and Fractogel TSK HW-55 (S) gel chromatography. Molecular weight of the purified lysozyme inhibitor was estimated to be 18, 000–20, 000 by SDS-PAGE and HPLC, and was composed of 71% amino acid and 23% total sugar. Serine, glycine, and alanine in a 3:2:1 molar ratio were the major amino acids, calculated to be 32.8, 20.3, and 11.4% (mol%), respectively. Glucose and mannose were the major sugar components of the inhibitor. The inhibitor was stable at pH 5 to 8 and was stable under 50 °C. Only hen egg-white lysozyme was inhibited by the purified inhibitor but not the other tested enzymes such as lysozyme of celery, turnip; lytic enzyme of Pseudomonas aeruginosa M-1001; chitinase/lysozyme of P. aeruginosa K-187; or cellulase and xylanase of Streptomyces actuosus A-151 and Aspergillus sp. G-393. The inhibition of lysozyme to the bacterial cell lytic activity by the purified inhibitor was 100%. 相似文献
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ZHANG Yifeng GUO Hong ZHANG Guangming YAN Xiuyun YIN Shougen ZHANG Zhengpu Institute of Taitai Pharmaceutical Co. Ltd Shengzhen China State Key Lab. of Functional Polymeric Materials for Adsorption Separation Institute of Polyme 《Chinese Journal of Reactive Polymers》2002,(1)
1. INTRODUCTION Fig.1 The Chemical Structure of Milupeinan As a new type of antibiotics Milupeinan, not only possesses antibacterial activities against a wide range of Gram-positive and Gram-negative bacteria, but also higgh stability under th… 相似文献
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Braga WS Kimura NM Luders DD Sampaio AR Santoro PA Palangana AJ 《The European physical journal. E, Soft matter》2007,24(3):247-250
The phase diagram is an interesting field of research, particularly in lyotropic liquid crystals (LLC). In this way, one of the most important phase diagrams of this LLC system was reported by Yu and Saupe. Two uniaxial (calamitic--N(C) and discotic--N(D)) and one biaxial nematic (N(B)) phases were determined by these authors. Furthermore, in this phase diagram the classical isotropic phase (I was observed at high temperature as well as a reentrant isotropic phase (I(RE)) which takes place at lower temperature. Later, this phase diagram was also studied by several authors and in all cases the I(RE)-N(C)-I phase transitions were not observed. In this work, we present a study of this phase diagram through digital image processing and refractometry optical techniques. The occurrence of these phase transitions is investigated and characterized. In addition, the order parameter is obtained based on the Vuks hypothesis from a particular point, in the range of the N(C) phase, where the absolute value of the optical birefringence (Deltan is maximum. 相似文献
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The stochastic integrals of M- type 2 Banach valued random functions w.r.t. compensated Poisson random measures introduced in (Rüdiger, B., 2004, In: Stoch. Stoch. Rep., 76, 213–242.) are discussed for general random functions. These are used to solve stochastic integral equations driven by non Gaussian Lévy noise on such spaces. Existence and uniqueness of the path wise solutions are proven under local Lipshitz conditions for the drift and noise coefficients on M-type 2 as well as general separable Banach spaces. The continuous dependence of the solution on the initial data as well as on the drift and noise coefficients are shown. The Markov properties for the solutions are analyzed. 相似文献
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The stochastic nonlinear complementarity problem has been recently reformulated as an expected residual minimization problem which minimizes an expected residual function defined by an NCP function. In this work, we show that the expected residual function defined by the Fischer–Burmeister function is an M-4RTM2SW-1-11/0?wchp=dGLzVlz-zSkzV" alt="View the MathML source" title="View the MathML source" align="absbottom" border="0" height=13 width="24"/> function. 相似文献
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A projected subgradient method for solving generalized mixed variational inequalities 总被引:1,自引:0,他引:1
We consider the projected subgradient method for solving generalized mixed variational inequalities. In each step, we choose an εk-subgradient uk of the function f and wk in a set-valued mapping T, followed by an orthogonal projection onto the feasible set. We prove that the sequence is weakly convergent. 相似文献
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The purpose of this work is to study the possibility of anionic dyes Reactive Red M-8B(RR) and Direct Green B(DG) adsorbed on chitosan-modified diatomite. The characteristics of adsorbent, adsorption isotherms and the influence of adsorption time, temperature and pH were researched in this work. The results show that the mo- dified diatomite had a much better adsorption capability than the natural diatomite. The adsorption capacities of chitosan-modified diatomite for RR and DG were 94.46 and 137.0 mg/g, respectively. Both adsorption time and adsorption temperature provided a positive effect on the dye adsorption. Within the experimental pH range, the adsorbance was enhanced at lower pH but reduced sharply at high pH. On the basis of the experimental results and discussion, electrostatic attraction is considered as the main mechanism of this chemisorption. 相似文献
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Qingyu Kong Kasper S. KjaerKristoffer Haldrup Stephan P.A. SauerTim Brandt van Driel Morten ChristensenMartin M. Nielsen Michael Wulff 《Chemical physics》2012,393(1):117-122
The [Pt2(H2P2O5)4]4− ions in the ground and excited states and the excited-state complexes M-[Pt2(H2P2O5)4]3− and M2-[Pt2(H2P2O5)4]2− (M = Ag, Tl) were studied in solution with various density functional theory (DFT) functionals from Gaussian 09 and Amsterdam Density Functional (ADF) programs. Calculated results were compared with ultrafast X-ray solution scattering data. Time dependent DFT (TD-DFT) calculations with the B3PW91 functional and unrestricted open shell calculations with the mPBE functional produce good agreement with the experimental results. Compared to gas phase calculations, the surrounding solvent is found to play an important role to shorten the Pt-Pt and M-Pt (M = Ag, Tl) bond lengths, lowering the molecular orbital energies and influences the molecular orbital transitions upon excitation, which stabilizes the excited transient molecules in solution. 相似文献