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1.
A V Khramtsov V V Shcherbukhin I A Morozov K B Ma?orov V M Zemskov 《Tsitologiia》1985,27(9):1055-1058
The interrelation between structural changes and oxygen consumption by the phagocyting macrophage was studied. The mean number of phagocyted particles was estimated by the method of stereological transformation. It is found that the uptake of yeast particles and CN- -nonsensitive oxygen consumption is related to the concentration of yeast cells in the incubation medium. A positive correlation was established between the oxygen consumption and the mean number of phagocyted particles. The results obtained may suggest that the "respiration burst" takes place in the contact area of the macrophage and the phagocyted material, and its extent probably depends on the surface of that contact area. 相似文献
2.
Positive selection is a general phenomenon in the evolution of abalone sperm lysin 总被引:15,自引:21,他引:15
Lysin is a 16kDa acrosomal protein used by abalone sperm to create a hole
in the egg vitelline envelope (VE). The interaction of lysin with the VE is
species-selective and is one step in the multistep fertilization process
that restricts heterospecific (cross-species) fertilization. For this
reason, the evolution of lysin could play a role in establishing prezygotic
reproductive isolation between species. Previously, we sequenced sperm
lysin cDNAs from seven California abalone species and showed that positive
Darwinian selection promotes their divergence. In this paper an additional
13 lysin sequences are presented representing species from Japan, Taiwan,
Australia, New Zealand, South Africa, and Europe. The total of 20 sequences
represents the most extensive analysis of a fertilization protein to date.
The phylogenetic analysis divides the sequences into two major clades, one
composed of species from the northern Pacific (California and Japan) and
the other composed of species from other parts of the world. Analysis of
nucleotide substitution demonstrates that positive selection is a general
process in the evolution of this fertilization protein. Analysis of
nucleotide and codon usage bias shows that neither parameter can account
for the robust data supporting positive selection. The selection pressure
responsible for the positive selection on lysin remains unknown.
相似文献
3.
Mestechkina N. M. Lobanova I. E. Anulov O. V. Shcherbukhin V. D. 《Applied Biochemistry and Microbiology》2001,37(4):388-391
A galactomannan with a molecular weight of 735 kDa was first isolated and purified from seeds of ambiguous crazyweed Oxytropis ambigua(Pall) DC (family Leguminosae) with a yield of 3.6%. Its aqueous solutions displayed an optical activity ([]
D
= 73.32°) and high viscosity ([] = 644 ml/g). Chemical analysis and 13C-NMR spectroscopy revealed the presence of D-mannopyranose and D-glucopyranose in the heteropolysaccharide at a molar ratio of 1.39 : 1. The linear backbone of its macromolecule consists of 1,4--D-mannopyranose residues. Single -D-galactose residues substitute 72% of the mannoses to form branches. 相似文献
4.
Edvinsson KM Herslöf M Holm P Kann N Keeling DJ Mattsson JP Nordén B Shcherbukhin V 《Bioorganic & medicinal chemistry letters》2000,10(5):503-507
Unsymmetrical diamide libraries have been prepared by a general and versatile solid phase route, using diacid templates in combination with aromatic and aliphatic amines chosen with the help of statistical experimental design. The compounds were tested as potential inhibitors of osteoclast vacuolar ATPase. 相似文献
5.
Mestechkina NM Egorov AV Anulov OV Shcherbukhin VD 《Prikladnaia biokhimiia i mikrobiologiia》2005,41(3):324-329
Galactoglucomannans were isolated by selective precipitation from aqueous and alkaline extracts of endosperm and hulls of Cercis canadensis, a member of the family Fabaceae. Their monosaccharide composition (Man: Gal: Glu) was as follows: 10.4: 0.9: 1 (polysaccharide from the endosperm) and 4.5: 0.9: 1 (polysaccharide from the hulls). The identity of IR spectra was indicative of the commonness of their structure. Analysis of the structure of the galactoglucomannan from endosperm by 13C NMR spectroscopy showed that its main chain consisted of 1,4-beta-D-manno- and 1,4-beta-D-glucopyranose. Part of mannose residues in the chain were substituted at C6 with single residues of alpha-D-galactopyranose. Galactoglucomannans are located in different part of the seed and implement different functions. 相似文献
6.
N. M. Mestechkina A. V. Egorov O. V. Anulov V. D. Shcherbukhin 《Applied Biochemistry and Microbiology》2005,41(3):283-288
Galactoglucomannans were isolated by selective precipitation from aqueous and alkaline extracts of endosperm and hulls of Cercis canadensis, a member of the family Fabaceae. Their monosaccharide composition (Man : Gal : Glu) was as follows: 10.4 : 0.9 : 1 (polysaccharide from the endosperm) and 4.5 : 0.9 : 1 (polysaccharide from the hulls). The identity of IR spectra was indicative of the similarity of their structure. Analysis of the structure of the galactoglucomannan from endosperm by 13C NMR spectroscopy showed that its main chain consisted of 1,4--D-manno- and 1,4--D-glucopyranose. Part of the mannose residues in the chain were substituted at C6 with single residues of -D-galactopyranose. Galactoglucomannans are located in different parts of the seed and implement different functions.__________Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 3, 2005, pp. 324–329.Original Russian Text Copyright © 2005 by Mestechkina, Egorov, Anulov, Shcherbukhin. 相似文献
7.
S V Rodionov V V Shcherbukhin E N Nikolayeva V M Zemskov 《Journal of hygiene, epidemiology, microbiology, and immunology》1988,32(1):95-104
The heterogeneity of resident peritoneal macrophages and peritoneal macrophages was studied in different periods following oral administration of sodium nucleinate according to their ability to bind and phagocytize sheep erythrocytes opsonized by means of specific rabbit IgG. Using a mathematical method developed earlier, it has been possible to demonstrate that resident peritoneal macrophages can be divided into two subpopulations--actively and poorly binding macrophages but, after activation by sodium nucleinate--into three subpopulations. Fractionation of the macrophages according to their ability to adhesion within a temperature gradient has shown that the same peaks are traced in the fractions as in the overall pool of cells, but in different quantitative ratios. It has also been demonstrated that phagocytic activity is reduced in macrophages capable of adhesion to plastic at lower temperatures. 相似文献
8.
Mestechkina NM Shcherbukhin VD Bannikova GE Varlamov VP Drozd NN Tolstenkov AS Makarov VA Tikhonov VE 《Prikladnaia biokhimiia i mikrobiologiia》2008,44(1):111-116
Galactomannan from seeds of Cyamopsis tetragonoloba (L.) Taub. (guar) was depolymerized using immobilized enzymatic preparation celloviridin. A set of fragments whose molecular weights varied from 12.6 to 245.6 kDa was obtained. Sulfated derivatives of components of all fractions were synthesized, in which the content of HSO3(-) groups was 48.05% +/- 2.31. All preparations exhibited anticoagulant activity, which was recorded in vitro in two tests--aIIa and aXa. The antithrombin activity (aIIa) was high (up to 65-87 U/mg) and did not depend on the molecular weight of a sulfated derivative; in the second test (aXa), the effect of molecular weight was observed. Biospecific electrophoresis allowed us to detect the ability of galactomannan sulfates to form complexes with protamine sulfate, a classic antidote to heparin. 相似文献
9.
Determination of the Primary and Fine Structures of a Galactomannan from the Seed of Gleditsia triacanthos f. inermis L. 总被引:1,自引:0,他引:1
Egorov A. V. Mestechkina N. M. Shcherbukhin V. D. 《Applied Biochemistry and Microbiology》2003,39(4):398-402
Galactomannan, a polysaccharide with a molecular weight of 660 kDa, was isolated for the first time from the seed of Gleditsia triacanthos f. inermis (yield, 15.4%). Its aqueous solutions were optically active ([]
D
= +31.0°) and highly viscous ([] = 578 ml/g). Analysis of this heteropolysaccharide using chemical, enzymatic, and chromatographic procedures, as well as IR and 13C NMR spectroscopy, showed that it consists of D-mannopyranose and D-galactopyranose residues (molar ratio, 2.42 : 1). The main chain of this galactomannan comprises 1,4--D-mannopyranose residues, 41% of which are substituted at C6 with single residues of -D-galactopyranose. The probability of occurrence in the chain of mannobiose units substituted otherwise, determined experimentally, was 0.16 for the Man–Man unit, 0.50 for the Gal(Man–Man) and (Man–Man)Gal units, and 0.34 for the disubstituted Gal(Man–Man)Gal unit. 相似文献
10.
Mitochondrial DNA and bindin gene sequence evolution among allopatric species of the sea urchin genus Arbacia 总被引:3,自引:1,他引:2
Sea urchins of the genus Arbacia (order Stirodonta) have discontinuous
allopatric distributions ranging over thousands of kilometers.
Mitochondrial DNA (mtDNA) sequences were used to reconstruct phylogenetic
relationships of four Arbacia species and their geographic populations.
There is little evidence of genetic structuring of populations within
species, except in two cases at range extremes. The mtDNA sequence
differentiation between species suggests that divergence occurred about 4-9
MYA. Gene sequences encoding the sperm protein bindin and its intron were
obtained and compared with the mtDNA phylogeny. Sea urchins among the
well-studied echinoid order Camarodonta, with degrees of mtDNA divergence
similar to those of Arbacia species, are known to have remarkable variation
in bindin. However, in Arbacia, little variation in deduced amino acid
sequences of bindin was found, indicating that purifying selection acts on
the protein. In contrast, bindin intron sequences showed much
differentiation, including numerous insertion/deletions. Fertilization
experiments performed between a divergent pair of Arbacia species from the
Atlantic and Pacific Oceans revealed no evidence of blocks to gamete
recognition. In Arbacia, fertilization specificities may have evolved
relatively slowly as a result of extensive gene flow within species,
greater functional constraint on the bindin polypeptide, or reduced
selective pressure for species recognition in singly occurring species.
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