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991.
Irina Lundovskikh Ekaterina Dementieva Natalya Ugarova 《Applied biochemistry and biotechnology》2000,88(1-3):127-136
The authentic recombinant luciferase, the luciferase with the structure similar to that of the native protein, was obtained
using random mutagenesis, and its properties were studied in comparison with several fusion proteins. Thermoinactivation curves
of the recombinant luciferases within the 10–50°C temperature interval showed that thermoinactivation involves reversible
and irreversible steps. Immobilization of the recombinant Luciola mingrelica and Photinus pyralis firefly luciferases on BrCN-activated sepharose was carried out. Immobilization resulted in the preparation of enzymes with
high catalytic activity. Physicochemical properties and analytical characteristics of the immobilized recombinant and native
luciferases were studied. The catalytic properties of the immobilized recombinant L. mingrelica luciferase were close to those of the native luciferase but the former enzyme appeared to be significantly more stable. The
immobilized recombinant luciferases can be used for ATP assay within 0.01–10000 nM range. 相似文献
992.
Zhurova EA Stash AI Tsirelson VG Zhurov VV Bartashevich EV Potemkin VA Pinkerton AA 《Journal of the American Chemical Society》2006,128(45):14728-14734
Chemical bonding in the pentaerythritol tetranitrate crystal based on the experimental electron density obtained from X-ray diffraction data at 100 K and theoretical calculations at the experimental molecular geometry have been analyzed in terms of the Quantum Theory of Atoms in Molecules. Features of the intra- and intermolecular bond critical points and the oxygen atom lone-pair locations are discussed. Numerous intermolecular bonding interactions, including O...H and O...O, have been found and characterized. Atomic charges and atomic energies were integrated and compared with those for similar compounds. The N-O topological bond orders have been calculated for the first time, and the PETN atomic valences have been estimated. 相似文献
993.
Anokhina EV Go YB Lee Y Vogt T Jacobson AJ 《Journal of the American Chemical Society》2006,128(30):9957-9962
In the course of our investigation aimed at the preparation of homochiral coordination polymers using readily available in optically pure form ligands and building blocks of condensed metal polyhedra, we recently reported a one-dimensional nickel aspartate compound [Ni(2)O(l-Asp)(H(2)O)(2)].4H(2)O (1) based on helical chains with extended Ni-O-Ni bonding. Here we report a new nickel aspartate [Ni(2.5)(OH)(l-Asp)(2)].6.55H(2)O (2) with a three-dimensional Ni-O-Ni connectivity that forms at a higher pH and is based on the same helices as in 1 which are connected by additional nickel octahedra to generate a chiral open framework with one-dimensional channels with minimum van der Waals dimensions of 8 x 5 A. The crystal structure of 2 was determined by synchrotron single-crystal X-ray diffraction on a 10 x 10 x 240 microm crystal. 相似文献
994.
Yuri E. Geints Igor V. Minin Ekaterina K. Panina Alexander A. Zemlyanov Oleg V. Minin 《Optical and Quantum Electronics》2017,49(3):118
Photonic nanojet (PNJ) phenomenon arising near transparent dielectric microparticles subject to plane wave illumination in the visible is considered. The near-field light scattering patterns produced by shaped wavelength-sized particles (hexahedron, cuboid, sphere, hemisphere, axicon, assembled particles) are numerically simulated and key PNJ parameters are analyzed. Particle shape influence on the peak intensity and spatial resolution of produced PNJ is investigated. We demonstrate that due to the reciprocal action of spherical-type and conical-type focusing of the special type of composite particles constituted of a hemisphere and an axicon can produce highly localized PNJ with peak intensity considerable higher than that for isolated regular particle (sphere, microaxicon, hemisphere). 相似文献
995.
E. K. Beloglazkina A. G. Majouga I. V. Yudin N. V. Zyk A. A. Moiseeva K. P. Butin 《Russian Chemical Bulletin》2005,54(9):2163-2168
A series of S-alkylated 2-thiohydantoin derivatives containing two 5-(2-pyridylmethylene)-2-sulfanyl-3,5-dihydro-4H-imidazol-4-one moieties linked through a polymethylene bridge with different numbers of carbon atoms was synthesized for
the first time. These compounds were obtained by the alkylation of 3-phenyl-5-(2-pyridylmethylene)-2-thiohydantoin or 3-methyl-5-(2-pyridylmethylene)-2-thiohydantoin
with different α,ω-dibromoalkanes in acetone or DMF in the presence of potassium carbonate. Complexes of these compounds (L)
with CoCl2 were synthesized. In all cases, the complexes L(CoCl2)2 were formed regardless of the ratio of L and inorganic salt introduced into the reaction. According to electronic spectroscopic
data, the cobalt atom in the complexes has a tetrahedral coordination environment. The synthesized ligands and complexes were
electrochemically studied by cyclic voltammetry.
Dedicated to Academician N. S. Zefirov on the occasion of his 70th birthday.
Deceased.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2099–2104, September, 2005. 相似文献
996.
An amine mono(phenolate) ligand bearing two side-arm donors led to octahedral trialkoxo and trialkyl group IV metal complexes, in which one of the donors was unbound, and to exceptionally stable cationic complexes in which the two side-arm donors were tightly bound. 相似文献
997.
998.
999.
Chemistry of Natural Compounds - For all the bisbenzyltetrahydroisoquinoline alkaloids considered except thalisopine, positive CEs are found in the case of the SS configuration and negative CEs in... 相似文献
1000.