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Biomedical subjects

G A Korneeva

Publications and source records attributed to G A Korneeva.

At least 19 recordsLinked to original sources

Catalytic activity of the nucleic acid component of the 1,4-alpha-glucan branching enzyme from rabbit muscles.

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.

1,4-alpha-Glucan Branching Enzyme↗

Primary structure of the nucleic acid from the 1,4-alpha-glucan branching enzyme.

The primary structure of the nucleic acid from the branching enzyme 1,4-alpha-D-glucan: 1,4-alpha-D-glucan 6-alpha-(1,4-alpha-glucano)-transferase (2.5-S RNA) isolated from rabbit muscles has been elucidated. The polyribonucleotide consists of 31 nucleotides; the unique features of the polyribonucleotide are the unusually high content of modified nucleotides (32%) and guanine residues (40%). Apparently 2.5-S RNA belongs to a class of nucleic acids unknown up to now. It is the first time that the structure of a nucleic acid component from a ribonucleoenzyme has been defined. This work is a preprequisite for gaining insight into the intimate activating effect of the poly-ribonucleotide on the enzyme action.

1,4-alpha-Glucan Branching Enzyme↗

[Structure-functional studies of the White sea water and bottom sediments].

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.

Amylases↗

[Extracellular protease activity in cryosphere components].

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.

Arctic Regions↗

[Dynamics of ecological-biochemical characteristics of the sea ice in the coastal zone of the White sea].

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.

Amylases↗

[New approaches to the diagnosis of carbohydrate metabolic disorders].

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.

Carbohydrate Metabolism↗

[Indication of Northern Caspian regions by biochemical (enzymatic) indices of water and bottom sediments].

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.

Environmental Monitoring↗

[Hydrolytic enzyme activities in the bottom sediment cores from Norwegian Sea and statistical analysis of their distribution].

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.

Amylases↗

[Ecological and biochemical evaluation of the environment of modern foraminifers of White Sea].

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.

Animals↗

[Ecological factors of hydrolytic enzyme activities in the Ob-Yenisey estuarine coastal waters in winter and their modelling].

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.

Cold Climate↗

[Variation of ecological status of Norwegian Sea water determined from hydrolytic enzyme activities].

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).

Amylases↗

[Seasonal trends in transformation of organic matter forms and enzyme activities in aquatic environment in winter in the Russian Arctic seas by the example of Yenisey Estuary].

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).

Arctic Regions↗

[Patterns of highly glycosylated proteins from human saliva].

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.

Chromatography, Agarose↗