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1.
Izv Akad Nauk Ser Biol ; (1): 94-103, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18491566

RESUMO

Oxygen exchange at the water-bottom interface in the northeastern Black Sea was studied using bottom tanks (fluxes and oxygen consumption for organic matter mineralization and for respiration of soil and water organisms). The relationship of biogenic fluxes and patterns of biochemical (enzyme) destruction of organic matter by the components of the bacterial and microproducer community was established. The prevalence of microbial oxidation of organic matter correlated with high proteolytic activity in near-bottom water. The principal significance of organic matter oxidation in near-bottom water for the phytoplankton and its respiratory expenditures was demonstrated both in the open system of the near-bottom layer and in the closed tank system. A similar trend was demonstrated for benthic organisms.


Assuntos
Ecossistema , Sedimentos Geológicos/química , Oxigênio/química , Água do Mar/química , Algoritmos , Animais , Biomassa , Sedimentos Geológicos/microbiologia , Fitoplâncton/fisiologia , Água do Mar/microbiologia , Movimentos da Água
2.
Izv Akad Nauk Ser Biol ; (6): 731-45, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17168471

RESUMO

Time variations in the main hydrochemical indices of water, organic matter forms, and hydrolytic enzyme activities in aquatic environment have been studied in winter in the southeastern Kara Sea (Yenisey Estuary with depths from 29 to 31 m). The abundance of some components of microproducer (pico-, nano-, and microphytoplankton) and bacterial plankton communities has been analyzed. High functional activity of microcommunities has been demonstrated in winter hydrobiological period. The hydrological, hydrochemical, biochemical, and biological indices of aquatic environment considerably varied in time while their stratification remained stable. The total resources of biologically accessible dissolved organic matter was evaluated by splitting the biological oxygen demand curves obtained under standard conditions (at 22 degrees C).


Assuntos
Ecossistema , Rios , Microbiologia da Água , Regiões Árticas , Monitoramento Ambiental , Oceanos e Mares , Estações do Ano , Sibéria
3.
Izv Akad Nauk Ser Biol ; (4): 467-78, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16212269

RESUMO

The capacity of biopolymer transformation involving efficient and highly specific natural enzyme mechanisms was studied in seawater of the dynamic zone of the Norwegian Sea (the Voring Plateau region). Vertical and spatial variation of proteinase and amylase activities was demonstrated in seawater and the potential rates of degradation of specific substrates, azocasein and Procion-5CX-modified starch, were calculated. High proteolytic activity was demonstrated for the upper photic layer (0-10 m) in the southwestern part of the polygon (up to 88 U/l; v(pr) = 7.04 mg/l/h). Proteolytic activity in the abyssal layer (1500 m and below) sharply decreased to 8-16 U/1; v(pr) = 0.64-1.28 mg/l/h. Similar to other regions of the ocean, the pattern of amylase activity in seawater included low rates of polysaccharide destruction (0-4 U/I; v(st) = 0-0.2 mg/l/h) in water with high proteolytic capacity and, conversely, the top amylase activity (up to 246-490 U/l; v(st) 12.3-24.5 mg/l/h) in seawater layers with undetectable or low proteolytic activity. The spatial distribution of the enzyme activities can indicate the presence of water bodies of different genesis. In the southwestern part of the polygon, statistical analysis demonstrated high correlation between hydrophysical indices (temperature, salinity, and salinity gradient) and proteinase and amylase activities. The ecological evaluation based on express enzyme-substrate tests demonstrated a stressful situation for destruction of organic compounds of protein nature in both the photic layer and the layers below 1000 m (t(pr) > or = 10 h).


Assuntos
Amilases/análise , Monitoramento Ambiental , Peptídeo Hidrolases/análise , Água do Mar/química , Monitoramento Ambiental/métodos , Noruega , Oceanos e Mares , Valor Preditivo dos Testes
4.
Izv Akad Nauk Ser Biol ; (5): 601-25, 2004.
Artigo em Russo | MEDLINE | ID: mdl-15559141

RESUMO

The ice conditions at the Ob-Yenisey estuarine coastal waters with relatively diffuse ice cover have been described using the data obtained in the Kara Sea survey aboard the nuclear icebreaker Yamal in January 22-March 6, 2003. The data on the capacity and rate of enzymatic degradation of various forms of organic matter and on the associated ecological factors in the region of active sea water/continental water interaction are given. We analyzed spatial distribution of the main types of water bodies as well as the cascade structure formed by some biogeochemical barriers near the Ob-Yenisey flaw polynya. We also analyzed the correlations between the indices of extracellular biochemical activity in water and the main abiotic and biotic factors during the organotrophic phase. The processes determining the level of biochemical activity in winter water and the rates of potential degradation of various organic compounds are considered.


Assuntos
Ecossistema , Camada de Gelo/microbiologia , Modelos Biológicos , Rios/microbiologia , Água do Mar/microbiologia , Microbiologia da Água , Clima Frio , Oceanos e Mares , Estações do Ano
5.
Izv Akad Nauk Ser Biol ; (3): 345-51, 2004.
Artigo em Russo | MEDLINE | ID: mdl-15354962

RESUMO

Current ecological conditions in the regions of Bol'shoi Keretskii raid and Glubokaya Salma (Kandalaksha Bay, White Sea) were evaluated on the basis of structural and dynamic indices of the upper sediments in the context of specific composition of the benthic foraminiferal community. The distribution of the main species of living foraminifers was determined for the shallow and deep-sea groups. The relationship between populations of the most abundant species of living benthic foraminifers and hydrolytic enzyme activities providing for destruction of bottom organic matter at biochemical rates has been revealed.


Assuntos
Ecossistema , Eucariotos/química , Eucariotos/fisiologia , Sedimentos Geológicos/química , Biologia Marinha , Animais , Eucariotos/classificação , Oceanos e Mares , Federação Russa , Poluentes da Água/análise
6.
Izv Akad Nauk Ser Biol ; (1): 105-14, 2004.
Artigo em Russo | MEDLINE | ID: mdl-15049076

RESUMO

Proteinase and amylase enzyme activities were evaluated in bottom sediment cores from the Norwegian Sea collected along a transect from the summit plane of the Voring Plateau on the east to fault uplifts of the Yan-Mayen transform zone perpendicular to the present-day Norwegian Current. Spotted vertical distribution of hydrolytic enzyme activities by the location and depth of the cores and specific distribution of proteinase and amylase activities have been revealed in four bottom sediment cores (up to 300 cm; 5 cm resolution). Specific activity distribution has been revealed for different types of enzyme-sorbing bottom sediments. Current methods of statistical analysis and mathematical modeling were applied to reveal the relationship between enzymatic degradation of protein and polysaccharide organic compounds and the content of carbonates and organic matter in bottom sediments.


Assuntos
Amilases/metabolismo , Endopeptidases/metabolismo , Sedimentos Geológicos , Amilases/análise , Interpretação Estatística de Dados , Endopeptidases/análise , Análise Fatorial , Hidrólise , Matemática , Modelos Teóricos , Noruega , Oceanos e Mares
7.
Izv Akad Nauk Ser Biol ; (2): 206-13, 2003.
Artigo em Russo | MEDLINE | ID: mdl-12712582

RESUMO

The distribution of salinity, silicon and phosphorus contents, and hydrolytic enzyme activities along a sea-coast transect was studied in melted ice cores and water samples taken from under the ice cover in the periods of active ice formation and melting in the Kandalaksha Bay, White Sea. The species list of identified algae was compiled, which included 170 species and varieties (90% of them belonged to diatoms). Strong correlations were revealed between the salinity of water samples and the content of silicon, protease activity, and the species composition of algae. Preliminary estimations of the rate of photosynthetic processes in individual cells of algae belonging to the mass species of the ice flora are discussed.


Assuntos
Bioquímica/métodos , Ecossistema , Monitoramento Ambiental/métodos , Gelo/análise , Amilases/análise , Amilases/metabolismo , Regiões Árticas , Clima , Endopeptidases/análise , Endopeptidases/metabolismo , Eucariotos/classificação , Eucariotos/fisiologia , Oceanos e Mares , Fósforo/análise , Fósforo/química , Fotossíntese/fisiologia , Federação Russa , Água do Mar/química , Silício/análise , Silício/química , Cloreto de Sódio/análise , Cloreto de Sódio/química
8.
Izv Akad Nauk Ser Biol ; (5): 599-609, 2003.
Artigo em Russo | MEDLINE | ID: mdl-14735793

RESUMO

We evaluated ecological status in the region of mixing of river and sea waters in the northern Caspian Sea with high anthropogenic pressure. We studied the regions of Volga River fore-delta, the water areas neighboring ancient hydrological transects, and the sea regions between the transects. The water areas were evaluated by biochemical degradation of organic compounds (proteinase and amylase activities) in water and bottom sediments as well as hydrochemical indices of water (salt composition and contents of dissolved oxygen and biogenic compounds). In conditions of active vegetation of phytoplankton and higher aquatic plants soon after the highest wave of the Volga flood, we studied distribution of hydrolytic enzyme activities involved in the global production/destruction cycle of high molecular weight organic compounds (proteins and polysaccharides). The data obtained with the trypsin-azocasein and alpha-amylase-modified starch tests indicates pollution of water and surface sediments in the lower reaches of Volga and the inflow sea regions.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Água do Mar/química , Poluentes Químicos da Água/análise , Oceanos e Mares , Fitoplâncton/efeitos dos fármacos , Fitoplâncton/crescimento & desenvolvimento , Federação Russa
9.
Izv Akad Nauk Ser Biol ; (5): 625-33, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12400387

RESUMO

The extracellular protease activity was studied in the snow of sea and land ecosystems, core of pack ice, and sea water of Arctic for estimation of dynamic (enzymatic) processes of organic matter transformation in components of the natural ecosystems. Spatial and vertical distributions of extracellular enzymatic activity were established. The ecological situations in the studied regions was estimated using the express azocasein--trypsin test-system.


Assuntos
Ecossistema , Endopeptidases/metabolismo , Gelo , Água do Mar , Neve , Regiões Árticas , Endopeptidases/química , Sedimentos Geológicos
10.
Izv Akad Nauk Ser Biol ; (1): 51-4, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12068439

RESUMO

The river and lake water of Transuralia (Ob, Yenisei, and Tom rivers) and the Altai District (Katun River, Teletskoe Lake, and Korbu Waterfall) were studied for the first time using modern enzymatic methods. The self-purifying capacity of water and their quality were assessed according to the enzymatic test-systems.


Assuntos
Bioquímica/métodos , Ecologia , Água Doce/análise , Amilases/análise , Bashkiria , Endopeptidases/análise , Monitoramento Ambiental/métodos , Água Doce/química , Sibéria
11.
Izv Akad Nauk Ser Biol ; (1): 100-7, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11236571

RESUMO

Statistical analysis of dynamic indices of biopolymers enzymatic destruction in unstratified and stratified. White Sea water has revealed specific properties of protease and amylase activities. We analyzed the component composition and hydrolytic enzymatic activities in the surface layer of the bottom sediments (0-2 cm). The relationship between protease and amylase enzymatic activities in the surface sediments with different content of pelite fraction is discussed.


Assuntos
Sedimentos Geológicos/química , Água do Mar/análise , Amilases/análise , Amilases/metabolismo , Regiões Árticas , Biopolímeros/metabolismo , Endopeptidases/análise , Endopeptidases/metabolismo , Oceanos e Mares , Federação Russa , Água do Mar/química
12.
Izv Akad Nauk SSSR Biol ; (4): 575-81, 1992.
Artigo em Russo | MEDLINE | ID: mdl-1280659

RESUMO

A bioenergetic conception of insulin-independent diabetes mellitus (IIDM) is put forward. Molecular mechanisms of carbohydrate and fat metabolism are discussed which result in a vicious regulatory cycle to provoke a transition to stable pathology. Previously unknown role of human saliva in oral cavity in this regulatory cycle is revealed. New diagnostic tests are developed on the basis of the conception on IIDM pathogenesis. The results of clinical trials are presented which have been obtained during population screening.


Assuntos
Metabolismo dos Carboidratos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Diagnóstico Diferencial , Metabolismo Energético , Ácidos Graxos/metabolismo , Glucose/análise , Humanos , Saliva/química , Saliva/metabolismo , Coloração e Rotulagem
13.
Izv Akad Nauk SSSR Biol ; (1): 148-51, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1856359

RESUMO

Mucine-like glycoproteins have been studied by structural indication. Textures of these compounds have been described. Possibility for using mucines as matrix structures in microcrystallographic method of analysis of complex multicomponent systems has been discussed.


Assuntos
Mucinas/ultraestrutura , Proteínas e Peptídeos Salivares/ultraestrutura , Cromatografia em Agarose , Cromatografia em Gel , Cristalografia , Glicosilação , Humanos , Mucinas/química , Saliva/química , Proteínas e Peptídeos Salivares/química
17.
Nucleic Acids Res ; 15(4): 1745-52, 1987 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-2434932

RESUMO

2.5 S RNA, the nucleic acid component of the 1,4-alpha-D-glucan: 1,4-alpha-D-glucan 6-alpha-(1,4-alpha-glucano)-transferase from rabbit muscles, devoid of any protein, catalyses the branching reaction, as does the holoenzyme. The conclusion is drawn that 2.5 S RNA is a ribozyme. To get an insight into the significance of different parts of the molecule for the catalytic activity of 2.5 S RNA, a large fragment isolated from its partial RNAase A digest was investigated. This fragment which proved to be the middle part of polyribonucleotide chain containing all modified nucleotides exerts some catalytic activity, too.


Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Glucosiltransferases/metabolismo , RNA Ribossômico/metabolismo , RNA/metabolismo , Enzima Ramificadora de 1,4-alfa-Glucana/isolamento & purificação , Animais , Cinética , Músculos/enzimologia , RNA/isolamento & purificação , Splicing de RNA , RNA Catalítico , RNA Ribossômico/isolamento & purificação , Coelhos
19.
Mol Biol (Mosk) ; 17(6): 1186-95, 1983.
Artigo em Russo | MEDLINE | ID: mdl-6197623

RESUMO

The fluorescence yield and lifetime of ethidium bromide complexes with 1,4-alpha-glucan branching enzyme and its free nucleic acid component 2.5S RNA were measured. Both fluorescence parameters showed a 10-fold increase in comparison with those characteristics for the free dye. This increase allows to suggest the existence of double-stranded regions in 2.5S RNA both in the free as well as in the protein bound state. The coefficients of fluorescence polarization were also determined for ethidium bromide complexed with free and protein bound 2.5S RNA. They proved to be 13 and 18% respectively. No concentration depolarization was observed in both types of ethidium bromide and ethidium bromide--enzyme--RNA complexes. This proves that the double-stranded regions are rather short and that two ethidium bromide molecules can't be bound to each of them. The binding isotherms were measured for ethidium bromide absorbed on 2.5S RNA and on the holoenzyme. Their parameters napp and rmax are identical in the cases of free and protein bound 2,5S RNA (rmax = 0.046 +/- 0.001). However the binding constants of ethidium bromide complexes with free and protein bound 2.5S RNA differ significantly (Kapp = 2.2 X 10(6) M-1 for free 2.5S RNA and Kapp = 1.6 X 10(6) M-1 for the holoenzyme). The quantity of nucleotides involved in the two double-stranded regions accessible for ethidium binding is estimated to be about 28%. Increasing of Mg2+ ion concentration up to 10(-3) results in a decrease of ethidium bromide binding with double stranded regions. It may be due to a more compact tertiary structure of 2.5S RNA in the presence of Mg2+ in the free as well as in protein bound state.


Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana/análise , Etídio , Glucosiltransferases/análise , Conformação de Ácido Nucleico , RNA/análise , Adsorção , Animais , DNA/análise , Peso Molecular , Músculos/enzimologia , RNA de Cadeia Dupla/análise , Coelhos , Espectrometria de Fluorescência
20.
Mol Biol (Mosk) ; 16(4): 731-8, 1982.
Artigo em Russo | MEDLINE | ID: mdl-6214706

RESUMO

1.4-alpha-glucan branching enzyme (EC 2.4.1.18) from rabbit muscles with an essential 2.5S RNA component has been studied by limited trypsin treatment. Under a great variety of hydrolysis conditions the product resistant to subsequent action of trypsin was obtained. This product contains about 70% of protein and all 2.5S RNA of the original nucleoprotein and retains about 50% of original activity. Amino acids Composition showed, that the protein is of alkaline nature and is rich in lysine. The alkaline nature of protein remains unchanged after trypsinolysis. On the basis of these studies it was assumed that the presence of firmly attached to the protein 2.5S RNA protects the branching enzyme against more powerful trypsinolysis and hinders loss of activity of the branching enzyme.


Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Glucosiltransferases/metabolismo , Músculos/enzimologia , Tripsina/farmacologia , Aminoácidos/análise , Animais , Sítios de Ligação , Hidrólise , Ratos , Relação Estrutura-Atividade
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