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1.
P S Gromov A M Shandala L I Kovalev S S Shishkin 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(7):28-30
Fractionation of human erythrocyte membrane proteins was performed using a modification of two-dimensional gel electrophoresis described by P. O'Farrel with isoelectric point plotted against molecular mass. All major erythrocyte proteins, including high molecular weight proteins, such as spectrin and band 3 protein, identified by one-dimensional sodium dodecyl sulfate gel electrophoresis, were visualized by silver staining of two-dimensional gels. All in all about 50 polypeptides were distinguished on two-dimensional electrophoretic patterns. Preliminary protein map was developed. 相似文献
2.
In somatic hybrids between tumourous Nicotiana tabacum (B6S3) and normal mesophyll Atropa belladonna cells, the following traits, directly or indirectly connected with T-DNA gene expression and tumourous growth, were analysed: lysopine dehydrogenase activity (LpDH), shoot suppression, root suppression, ability to grow on media with D-lactose as a sole carbon source and resistance to 2-aminoethylcysteine, 5-bromodeoxyuridine and 5-methyltryptophan. Dominant (semidominant) expression was observed for all but one trait studied, e.g. shoot suppression which behaved as a recessive character.Abbreviations LS-H
Linsmaier and Skoog (1965) hormone-free medium
- NAA
Naphtaleneacetic acid
- BAP
6-Benzylaminopurine
- 2,4-D
2,4-Dichlorophenoxyacetic acid
- 5-BUdR
5-Bromodeoxyuridine
- 2-AEC
2-Aminoethylcysteine
- 5-MT
5-Methyltryptophan 相似文献
3.
Deletion analysis of the SUP35 gene of the yeast Saccharomyces cerevisiae reveals two non-overlapping functional regions in the encoded protein 总被引:13,自引:0,他引:13
Michael D. Ter-Avanesyan Vitaly V. Kushnirov Adilya R. Dagkesamanskaya Svetlana A. Didichenko Yury O. Chernoff Sergey G. Inge-Vechtomov Vladimir N. Smirnov 《Molecular microbiology》1993,7(5):683-692
SUP35is an omnipotent suppressor gene of Saccharomyces cerevisiae coding for a protein consisting of a C-terminal part similar to the elongation factor EF-1α and a unique N-terminal sequence of 253 amino acids. Twelve truncated versions of the SUP35 gene were generated by the deletion of fragments internal to the coding sequence. Functional studies of these deletion mutants showed that: (i) only the EF-1α-like C-terminal part of the Sup35 protein is essential for the cell viability; (ii) overexpression of either the N-terminal part of the Sup35 protein or the full-length Sup35 protein decreases translational fidelity, resulting in omnipotent suppression and reduced growth of [psi+] strains; (iii) expression of the C-terminal part of the Sup35 protein generates an antisuppressor phenotype; and (iv) both the N- or C-terminal segments of the Sup35 protein can bind to 80S ribosomes. Thus, the data obtained define two domains within the Sup35 protein which are responsible for different functions. 相似文献
4.
Raisa P. Gorshkova Natalia I. Korchagina Tatianna A. Medonova Elena N. Kalmykova Natalia N. Besednova Yury S. Ovodov 《Carbohydrate research》1980,84(2):237-243
Lipopolysaccharides (LPS) from various strains of Yersinia pseudotuberculosis type V have been isolated and characterised. Differences in sugar composition and serological activity of LPS from various strains within the same subtype of Y. pseudotuberculosis have been revealed. 相似文献
5.
Makarova Kira S.; Mazin Alexander V.; Wolf Yury I.; Soloviev Victor V. 《Bioinformatics (Oxford, England)》1992,8(5):425-431
A computer system DIROM for oligonucleotide-directed mutagenesisand artificial gene design has been designed for better experimentalplanning and control. DIROM permits searching for optimal oligonucleotideswith respect to certain important parameters, namely sufficientenergy of oligonucleotide-target hybridization, the secondarystructure of oligonuc-tide and target DNA, the presence of alternatebinding sites in the target DNA and terminal G/C pairs. It canalso be used to plan polymerase chain reaction experiments,for optimal primer selection, in sequencing, etc. DIROM enablesone to search for both existing and potential restriction sites,to perform vector + target sequence construction. The systemconsists of a set of original algorithms that formalize theempirical knowledge of oligonucleotide action as primers. 相似文献
6.
Yury S. Ovodov Raisa G. Ovodova Valenthina I. Shibaeva Lidia V. Mikheyskaya 《Carbohydrate research》1975,42(1):197-199
Traces of either ferrous or ferric salts greatly increase the rate of the stepwise degradation of reducing sugars by alkaline hydrogen peroxide, as measured by formation of formic acid; addition of larger proportions of iron salts causes relatively smaller effects. The results showed that, unless unusually strict precautions are taken to exclude traces of iron, the free-radical cleavage of the hydroperoxide adducts of reducing sugars is far more rapid than the ionic cleavage. The catalytic effect of iron salts is counteracted by addition of magnesium salts. With d-glucose, inhibition of the catalytic effect of iron by magnesium depends on both the magnesium-iron ratio and the concentration at a given ratio. Measurements with various molar proportions of the salts indicated that a magnesium-iron complex, containing six atoms of magnesium to one of iron, is formed. Presumably, removal of iron by formation of this complex inhibits the free-radical degradation of hydroperoxide adducts. In marked contrast to the results obtained with reducing sugars, the degradation of potassium glyoxylate and of glyoxal by alkaline hydrogen peroxide is extremely rapid, and not catalyzed by iron or inhibited by magnesium. The results are in accord with an ionic, rather than a free-radical, cleavage of the hydroperoxide adducts of these compounds. The rapidity of the ionic reaction may be attributed to the ready availability of an electron pair from the adjoining carbon atom. 相似文献
7.
A list of 285 species of Sarcophagidaе in the Middle East countries is presented with distributional data, including Bahrain (3 species), Cyprus (46), Egypt (both African and Asian parts) (114), Iran (83), Iraq (17), Israel (113), Jordan (14), Kuwait (3), Lebanon (13), Oman (2), Gaza Strip (5), Palestinian Authority (42), Quatar (1), Saudi Arabia (37), Syria (42), Turkey (both European and Asian parts) (157), United Arab Emirates (14) and Yemen (15). Three new synonyms are established: Blaesoxipha delilah Lehrer, 2006 = Agriella setosa Salem, 1938, syn. n.; Blaesoxipha nahaliana Lehrer, 2008 = Blaesoxipha popovi Rohdendorf, 1937, syn. n.; and Liosarcophaga daccanella Lehrer, 2008 = Liosarcophaga (s. str.) dux (Thomson, 1869), syn. n. Four new combinations for species names are proposed: Liopygia (Engelisca) adhamae (Lehrer & Abou-Ziad, 2008), comb. n.; Liosarcophaga (s. str.) pedestris (Villeneuve, 1910), comb. n.; Liosarcophaga (Pandelleisca) theodori (Lehrer, 1998), comb. n., and Liosarcophaga (Pharaonops) tewfiki (Salem, 1940), comb. n. 相似文献
8.
Kulakov IuK Zheludkov MM Tolmacheva TA Alekseeva NV Kovalev IuN Skavronskaia AG Gintsburg AL Mikhaĭlova IuP Kalmykov VV Shumilov KV 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》2000,(4):7-12
Ten strains isolated from sick dogs in 1998 in St. Petersburg were studied by traditional and molecular biological methods of Brucella identification. PCR study confirmed that the isolated cultures were Brucellae, and comparative study of the traditional phenotypical characteristics and protein and antigenic composition allowed referring all the isolated strains to B. canis. Traditional identification showed similarity of 7 strains with the reference B. canis strain RM6/66, and 3 strains were similar to B. canis Mex 51 strain. These results confirmed the division of B. canis into two biovars. Polyacrylamide gel electrophoresis with sodium dodecyl sulfate demonstrated the identity of protein profiles of 10 strains isolated from dogs to the reference B. canis RM6/66 strain. Immunoblotting analysis with S- and R-specific rabbit antisera also demonstrated the identity of antigens binding IgG antibodies in the strains isolated from dogs to the reference B. canis RM6/66 strain. 相似文献
9.
10.
S. M. Zyryanov A. S. Kovalev D. V. Lopaev E. M. Malykhin A. T. Rakhimov T. V. Rakhimova K. N. Koshelev V. M. Krivtsun 《Plasma Physics Reports》2011,37(10):881-889
Low-pressure hydrogen is an important component of the working medium in extreme ultraviolet (EUV) projection lithography.
Under the action of EUV photons and fast secondary electrons on the gas medium, plasma and atomic hydrogen, actively interacting
with the surface, are produced. This interaction is very important, because it largely determines the lifetime of the multilayered
EUV optics. In this study, the loss of atomic hydrogen under the conditions of a low pressure (<10 Torr) RF plasma discharge
on the surfaces of materials used in EUV lithography is investigated. The surface loss probabilities of H atoms on these materials
are measured. It is shown that surface recombination of atomic hydrogen goes according to the Eley-Rideal mechanism via direct
recombination of H atoms from the gas phase with chemically and physically adsorbed atoms. In this case, the surface recombination
probability is mainly determined by the density of chemical adsorption sites. The density of adsorption sites and the desorption
energy of H atoms are estimated. The desorption energy of physically adsorbed H atoms on pure metal surfaces (or surfaces
exposed to plasma) is about 0.5 eV, and the density of sorption sites is close to the surface density of atoms. This results
in a high loss probability of H atoms on metals (∼0.1). Therefore, to provide efficient transportation of hydrogen atoms,
it is necessary to use materials with the lowest loss probability of H atoms, i.e., dielectrics. 相似文献