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1.
Mikrobiologiia ; 83(3): 312-9, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25844441

RESUMO

The taxonomic composition of bacteria associated with the Cephalotrix simula proboscis worm was studied and screening of the tetrodotoxin (TTX)-producing bacteria was carried out using confocal laser scanning microscopy and polyclonal antibodies. Bacterial isolates were identified using the 16S rRNA gene sequencing and phenotypic characteristics. A Bacillus species was found to be responsible for tetrodotoxin production in C. simula proboscis worms. Vibrio spp. predominated in the associated microflora (68.18% of the total number of isolates). Analysis of the sensitivity of 16 strains to antibiotics of various classes revealed multiple resistance to three or more antibiotics in all studied isolates. Poor growth of most of the isolates on all laboratory media was an indirect confirmation of the symbiotic relationships between the micro- and macroorganisms.


Assuntos
Bacillus/metabolismo , Invertebrados/microbiologia , Tetrodotoxina/metabolismo , Vibrio/metabolismo , Animais , Antibacterianos/farmacologia , Organismos Aquáticos , Bacillus/genética , Bacillus/isolamento & purificação , Farmacorresistência Bacteriana Múltipla , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Simbiose , Vibrio/efeitos dos fármacos , Vibrio/genética , Vibrio/isolamento & purificação
2.
Genetika ; 49(9): 1065-78, 2013 Sep.
Artigo em Russo | MEDLINE | ID: mdl-25486774

RESUMO

The intraspecific polymorphism of Sakhalin taimen Parahucho perryi (Brevoort, 1856), Salmonidae, was assessed via the RFLP analysis of mitochondrial DNA fragments that contain Cytb, the control region (D-loop), and the genes for the NADH dehydrogenase subunits 1-4, as well as the sequencing of the mitochondrial DNA COI gene. The statistically significant differentiation of the populations from the mainland coast of the Sea of Japan and the eastern and western coasts of Sakhalin Island was demonstrated. The higher level of haplotype diversity in Sakhalin populations compared to Primorye populations and the structure of haplotype genealogies suggested that all populations of Parahucho perryi originated from a common ancestor, which probably lived on the western coast of the Sakhalin Island.


Assuntos
DNA Mitocondrial/genética , Polimorfismo de Fragmento de Restrição , Salmonidae/genética , Animais , Citocromos b/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genética Populacional , Haplótipos , NADH Desidrogenase/genética , Filogenia , Sibéria
3.
Genetika ; 48(7): 844-54, 2012 Jul.
Artigo em Russo | MEDLINE | ID: mdl-22988770

RESUMO

Pond smelt Hypomesus olidus (Pallas, 1814), one of the five species of the genus Hypomesus, family Osmeridae, was examined for intraspecific variation of the mitochondrial DNA cytb (1062 bp) and COI (567 bp) genes. Among the ten single substitutions discovered, only one, leading to the substitution of isoleucine by valine, was nonsynonymous, while the remaining substitutions were synonymous. The degree of genetic divergence among pooled nucleotide sequences in H. olidus populations examined constituted 0.4% on average, ranging from 0.2 to 0.6%. These values were not higher than the levels of divergence between the individuals within the populations. Phylogenetic analysis of the populations examined did not reveal their subdivision depending of their geographic location, and pointed to the absence of intraspecific differentiation of the species.


Assuntos
Citocromos b/genética , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Osmeriformes/genética , Substituição de Aminoácidos/genética , Animais , Filogenia , Polimorfismo Genético , Lagoas
4.
Genetika ; 47(8): 1081-96, 2011 Aug.
Artigo em Russo | MEDLINE | ID: mdl-21954617

RESUMO

Smelts of the genus Osmerus, O. eperlanus and O. mordax dentes, inhabiting the basins of the Atlantic, Arctic, and Pacific oceans were investigated using RFLP analysis of the mitochondrial DNA segments A8/A6/COIII/ND3 and ND3/ND4, and sequencing of the cytb and COI genes (mtDNA), and intron 1 of the rpS7 gene (nDNA). A total of 14 samples from the populations from most part of the Russian range were examined. The mean values of haplotype and nucleotide diversity constituted 0.5997 +/- 0.11264 and 0.003201 for O. m. dentex, and 0.3086 +/- 0.09892 and 0.000431 for O. eperlanus, respectively. The high level of interspecific diversity (12.94%) along with the low level of intraspercific diversity (0.049% for O. m. dentex, and 0.001% for O. eperlanus was observed. The dendrograms (UPGMA, NJ, MP, and BA) constructed using the data of RFLP analysis of mtDNA, along with the sequencing data of mitochondrial and nuclear genes were congruent. The representatives of O. eperlanus and O. m. dentex formed steady clusters in accordance with their species affiliation, albeit without subdivision into local populations depending on their geographic locality.


Assuntos
DNA Mitocondrial/genética , Peixes/genética , Filogenia , Polimorfismo de Fragmento de Restrição , Animais , Genética Populacional/métodos , Humanos , Federação Russa , Especificidade da Espécie
5.
Genetika ; 47(3): 368-78, 2011 Mar.
Artigo em Russo | MEDLINE | ID: mdl-21542306

RESUMO

PCR-RFLP analysis of the ND3/ND4L/ND4 and 12S/16S rRNA regions and nucleotide sequence variation of the cytochrome b gene were used to study the mtDNA divergence in species of the family Cyprinidae, to examine the phylogenetic relationships of the species, and to identify their taxonomic status. The results indicated that an ancestral form diverged into silver crucian carp and crucian carp after its separation from the common carp lineage. The divergence of continental Carassius auratus gibelio and Japanese C. auratus cuvieri occurred more recently. Two well distinguishable mtDNA phylogroups, suggesting divergent evolution, were observed in continental C. auratus gibelio populations. The divergence was possibly related to the formation of two silver crucian carp groups with different types of reproduction, triploid gynogenetic and diploid gonochoric. At the same time, the results supported the high probability of current genetic exchange between the forms. In view of these findings and high morphological similarity of the two forms, they were not considered to be separate species.


Assuntos
Cyprinidae/classificação , Cyprinidae/genética , DNA Mitocondrial/genética , Animais , Especiação Genética , Variação Genética/genética , Filogenia , Filogeografia , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição
6.
Genetika ; 46(7): 967-73, 2010 Jul.
Artigo em Russo | MEDLINE | ID: mdl-20795501

RESUMO

The mtDNA divergence was examined in some families of anadromous and semi-anadromous fish. Heterogeneous distribution of the divergence values along the scale was demonstrated. Statistically significantly higher number of the species pairs were characterized by divergence values ranging from 2 to 4% and 5 to 12% of nucleotide substitutions. These results suggest that in different monophyletic groups occupying common historical ranges, divergence-associated speciation often happened within similar time intervals. Comparison of the species divergence time calculated using the molecular clock pointed to the coincidence of the radiation periods in the taxa with paleogeological and paleoclimatic global changes in the history of Northern Pacific.


Assuntos
Evolução Biológica , Peixes/genética , Animais , Oceano Pacífico
7.
Genetika ; 46(7): 974-80, 2010 Jul.
Artigo em Russo | MEDLINE | ID: mdl-20795502

RESUMO

The congruence between molecular markers, identifying the presence of the Y chromosome, and secondary sexual characters was examined in Asian populations of five Pacific salmon species: pink salmon (Oncorhynchus gorbuscha), chum salmon (O. keta), sockeye salmon (O. nerka), chinook salmon (O. tschawytsha), and sima (O. masou). It was demonstrated that in all species examined, the presence or absence of sex-specific molecular markers was to a considerable degree congruent with secondary sexual characters, but in some cases, an incongruence was found. These findings suggested that the mechanism underlying this phenomenon was similar or identical in all species examined. Possible genetic and physiological explanations of this phenomenon are discussed.


Assuntos
Marcadores Genéticos/genética , Oncorhynchus/genética , Caracteres Sexuais , Animais , Feminino , Masculino
8.
Genetika ; 46(1): 79-91, 2010 Jan.
Artigo em Russo | MEDLINE | ID: mdl-20198883

RESUMO

Putative phylogenetic relationships between all smelt species inhabiting Russian waters were studied using RFLP and the data on divergence between nucleotide sequences of the mitochondrial gene encoding cytochrome b. All types of phylogenetic trees (NJ, MP, and Bayesian) displayed stable clustering into isolated groups corresponding to the division of the subfamily Osmerinae into three genera, Mallotus, Osmerus, and Hypomesus. It was demonstrated that the Mallotus phylum was the first to diverge from a hypothetical common ancestor of the smelts. Later, it divided into two clusters corresponding to the modern subspecies Mallotus villosus villosus and M. v. catervarius. The phylum of the genus Osmerus diverged later than the genus Mallotus and also divided into two clusters, one including O. mordax of the Pacific (Sea of Japan) and Arctic (Kara and Barents Seas) basins and the other, anadromous and resident ecotypes of the O. eperlanus from the Baltic Sea basin. The smelts of the genus Hypomesus is the youngest phylogenetic group among the taxa studied; it forms three individual clusters matching the species H. olidus, H. nipponensis, and H. japonicus. The proposed phylogenetic hypothesis is discussed from the standpoint of its compliance with the phylogenetic constructions based on the external morphological and osteological traits.


Assuntos
Citocromos b/genética , Osmeriformes/classificação , Polimorfismo de Fragmento de Restrição , Animais , Variação Genética , Osmeriformes/genética , Filogenia
9.
Genetika ; 46(11): 1533-43, 2010 Nov.
Artigo em Russo | MEDLINE | ID: mdl-21261064

RESUMO

The congruence between secondary sexual characters and molecular markers, linked to the Y chromosome was examined in Asian populations of five Pacific salmon species of the genus Oncorhynchus. Our results support the existence of discrepancy between secondary sexual characters and sex-linked molecular markers in all species examined, which suggests the existence of similar or identical mechanism responsible for this phenomenon in Pacific salmons. Clinal latitudinal directional variation of the character confirmed the possibility that this phenomenon could be adaptively important, including its importance for regulation of the population number. In addition to natural factors affecting the degree of discrepancy between morphobiological characters and molecular markers in the Pacific salmon populations, anthropogenic factors, in particular intense fishery of certain population or population group, is also important.


Assuntos
Oncorhynchus/genética , Animais , Marcadores Genéticos , Oceanos e Mares , Fenótipo , Dinâmica Populacional , Caracteres Sexuais , Especificidade da Espécie , Cromossomo Y
11.
Genetika ; 44(7): 906-12, 2008 Jul.
Artigo em Russo | MEDLINE | ID: mdl-18767538

RESUMO

Long-term changes in the sex ratio have been studied in pink salmon (Oncorhynchus gorbuscha) and chum salmon (O. keta) populations of Kamchatka and Sakhalin. It has been demonstrated that these changes are an adaptation to population dynamics: an increase in the population size is accompanied by a shift towards a higher proportion of males; a decrease in population size, by a shift towards a higher proportion of females. The correspondence between morphological and molecular characters in populations of the two species has been analyzed in order to determine the mechanism of sex ratio control. In some pink salmon and chum salmon populations, there is a discrepancy between sex identifications based on morphological characters and molecular markers. This discrepancy is assumed to be accounted for by sex inversion mechanisms, which may be population- or region-specific. In two cases, it has been found that the sex ratio discrepancy in populations is related to the numbers of fish in subsequent generations. These findings suggest that sex inversion may be related to population size control.


Assuntos
Oncorhynchus keta/genética , Salmão/genética , Razão de Masculinidade , Animais , Feminino , Marcadores Genéticos , Genética Populacional , Masculino , Sibéria , Fatores de Tempo
12.
Genetika ; 44(7): 972-82, 2008 Jul.
Artigo em Russo | MEDLINE | ID: mdl-18767546

RESUMO

The variation in mitochondrial DNA (mtDNA) structure among Chinook Salmon Oncorhynchus tschawytscha Walbaum populations from Kamchatka was inferred from restriction length polymorphism analysis using eight restriction endonucleases. The nucleotide sequence variation in three amplified mtDNA regions was examined at seven polymorphic restriction sites in 579 fish from 13 localities. Based on the frequencies of 11 combined haplotypes and the number of nucleotide substitutions, the among- and within-population variation was estimated. The heterogeneity test showed highly significant differences among all the populations. The estimated maximum time of independent divergence of the Asian Chinook salmon populations, whose differences was about 0.02% nucleotide substitutions, did not exceed 10000-20000 years. Apparently, the retreat of the late Pleistocene glacier triggered spreading, recolonization, and formation of the present-day pattern of the species subdivision into structural components.


Assuntos
DNA Mitocondrial/genética , Filogenia , Polimorfismo de Fragmento de Restrição , Salmão/genética , Animais , Haplótipos , Especificidade da Espécie
14.
Genetika ; 36(10): 1388-93, 2000 Oct.
Artigo em Russo | MEDLINE | ID: mdl-11094752

RESUMO

Mitochondrial DNA (mtDNA) variation was studied using restriction fragment length polymorphism (RFLP) in chum salmon populations from three rivers in southern Primorye and one river in Sakhalin Island. Significant differences were detected between the samples from Primorye and Sakhalin Island. No differences were found between the samples from the rivers of Primorye, which can be explained by a high rate of gene flow due to transplantation of spawn from one river to another. The effect of fish breeding on the chum salmon populations correlated with the indices of haplotype and nucleotide diversity (h and pi, respectively). The lowest diversity was found in the completely artificial population from the Ryazanovka River; the highest, in natural populations from the Narva and Naiba rivers. Frequencies of haplotypes in consecutive generations were significantly different, which confirms the effects of genetic drift on the small-size chum salmon populations of Primorye.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Oncorhynchus/genética , Animais , Água Doce , Haplótipos , Sibéria
15.
Mol Biol (Mosk) ; 22(2): 377-83, 1988.
Artigo em Russo | MEDLINE | ID: mdl-3393148

RESUMO

Inverted repeat DNA sequences during embryogenesis were tested by comparing the bulk inverted repeat taken from Strongylocentrotus intermedius sea urchin embryos at different stages of development. This fraction exhibited quantitative and qualitative changes. A reversible quantitative decrease was associated with the 16-cell embryo and blastula stages. Sizing on 1.5% agarose gel indicated that the length of the palindromic sequences at the early blastula stage was predominantly about 200 b. p., and at the pluteus stage 240 b. p. Sensitivity of the palindromic sequences to S1 nuclease digestion at the blastula and gastrula stages was different. It was shown that a specific set of the inverted repeats was included in fragments of DNA--comparising the origin of replication. The results suggest that the change of inverted repeats may be determined by replication processes.


Assuntos
Inversão Cromossômica , DNA/genética , Sequências Repetitivas de Ácido Nucleico , Ouriços-do-Mar/genética , Animais , Replicação do DNA , Eletroforese em Gel de Ágar , Ouriços-do-Mar/embriologia
16.
Mol Biol (Mosk) ; 21(5): 1346-51, 1987.
Artigo em Russo | MEDLINE | ID: mdl-3683377

RESUMO

Using the instability of replication loops as a method for the isolation of double-stranded nascent DNA from embryos of the sea urchin Strongylocentrotus intermedius, extruded DNA enriched for replication origins was obtained. The average length of the fragments of the DNA of this fraction was estimated to be about 800 base pairs. The origin-enriched nascent DNA strands were assayed for the presence of inverted repeats. The results show that the origin-enriched DNA is also enriched in inverted repeats. The bulk of palindromes in the total nuclear DNA was estimated to be 200 base pairs in length and from the origin-enriched DNA-150 base pairs.


Assuntos
Inversão Cromossômica , Replicação do DNA , DNA/isolamento & purificação , Sequências Repetitivas de Ácido Nucleico , Animais , Embrião não Mamífero , Ouriços-do-Mar
17.
Biokhimiia ; 50(9): 1553-9, 1985 Sep.
Artigo em Russo | MEDLINE | ID: mdl-4052511

RESUMO

Some properties of the palindromic sequences in the sea urchin Strongylocentrotus intermedius nuclear DNA have been studied. It was shown that the amount of "foldback HAP bound DNA" and the S1 nuclease resistant DNA depends on renaturation temperature and Na+ concentration in solution. The authentic fraction of inverted repeats comprises 10-15% of the total DNA. The complexity of the palindromic fraction is approximately 8,2 X 10(7) nucleotide pairs and the average number of inverted repeats approximates 5 X 10(5) per haploid genome. The renaturation kinetics of inverted repeats with excess of total homologous DNA indicates that these sequences are enriched with unique DNA. The possible function of palindromic sequences is discussed.


Assuntos
Inversão Cromossômica , DNA/genética , Sequências Repetitivas de Ácido Nucleico , Animais , Desnaturação de Ácido Nucleico , Ouriços-do-Mar/genética
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