[Isolation and properties of fish chymopsin]. / Vydelenie i nekotorye svoistva khimopsina ryb.

A simple and convenient method of fish chymopsin isolation from the acetone powder of pyloric appendices has ben developed using classical methods. The enzyme preparation includes 62-65% of protein, the specific weight of trypsin and chymopsin being 1000 and 3000 units per 1 mg of protein, respectively. Heterogeneity of the isolated chymopsin was shown using electrophoresis in PAAG. As to the degree of purity the given preparation is like to the bull chymopsin. Under identification of amino acid composition it is shown that the both chymopsins differ from each other to a certain extent. The preparation isolated from fish includes the less content of lysine that probably can evidence for the overwhelming quantity of serine proteases in anionic form as well as the less content of serine and leucine. At the same time the higher content of threonine, glutamic acid, proline, methionine is revealed in the fish chymopsin. Enzymatic properties of fish chymopsin as to the digestion of some low-molecular substrates have been studied. A comparative characteristic of their hydrolysis by the isolated preparation, bull chymopsin and pylochymopsin (fish preparation isolated on the biospecific sorbent) is presented. At any case the degree of hydrolysis of substrates by the both chymopsines is similar and to some extent different from the catalytic action of pylochymopsin.

[The amino acid composition of the antigenic structures of the human heart conduction system]. / Aminokislotnyi sostav antigennykh struktur provodiashchei sistemy serdtsa cheloveka.

Amino acid composition of proteins from antigen preparations of the human heart conduction system has been studied. Differences in amino acid composition and relative affinity of the structure of two groups were found: between the sinus and atrioventricular nodes, the His bundle and contractile myocardium.

[Collagen from human joint cartilage in deforming arthritis]. / Kollagen sustavnogo khriashcha cheloveka pri deformiruiushchem artroze.

Type II collagen of human cartilage has been comparatively studied in norm and at deforming arthrosis. Collagen preparations are characterized by aminoacid composition and electrophoretic mobility in polyacrylamide gel. It is supposed that at deforming arthrosis the degenerative-dystrophic processes in the articular cartilage of man are caused by appearance of procollagen.

[Correction with formate of metabolic disorders in alcoholic intoxication]. / Korrektsiia formiiatom metabolicheskikh narushenii pri alkogol'noi intoksikatsii.

Formate was studied for its effect on the content of acetaldehyde, activity of the total aldehyde dehydrogenase, content of substrates of glycolysis and tricarbonic-cycle and pool of free amino acids of rat tissues during alcohol intoxication. The introduction of formate during the acute alcohol intoxication lowers the acetaldehyde content in the blood; the ethanol load being prolonged--it increases the activity of aldehyde dehydrogenase and normalizes the content of pyruvate, glutamate and malate in the liver and glutamate and oxaloacetate in the brain, that evidences for the correction of metabolic disturbances in the organism.

[Structural-functional changes in plasma lipoproteins during vitamin D-deficient rickets in children]. / Strukturno-funktsional'nye izmeneniia lipoproteinov plazmy krovi pri vitamin-D-defitsitnom rakhite u detei.

The lipid composition and structure of low- and high-density lipoproteins (LDL and HDL) have been studied in children with the vitamin D-deficient rachitis. An increase of the cholesterol content in the atherogenic LDL against a background of its decrease in the antiatherogenic HDL has been revealed, that is analogous to the observed changes under the atherosclerosis development in adults. Due to the studies in the amino acidic composition and determination of the nature and quantity of the charged groups of lipoprotein particles accessible for titration definite, certain disturbance in the structure of lipoproteins are observed as such that may cause disturbances in their functional activity.

[Reaction of glycine with acetoacetate and various properties of the catalyzing enzyme from the rat liver]. / Reaktsiia glitsina s atsetoatsetatom i nekotorye svoistva kataliziruiushchego ee fermenta iz pecheni krys.

The enzymic interaction between acetoacetate and glycine which are added outside is established to occur in the tissue homogenates of the liver, kidneys and spleen of rats. The interaction leads to a decrease of the both components in the equivalent quantities. Homogeneous crystalline preparations of the enzyme catalyzing the above mentioned reaction are isolated from the liver tissues and purified. Certain properties of the enzyme are studied.

[Structural properties and lipid-binding characteristics of plasma fibrinogen and gamma-globulins in vitamin D-deficient rickets]. / Strukturnye osobennosti i lipidsviazyvaiushchaia sposobnost' fibrinogena i gamma-globulinov plazmy krovi pri vitamin-D-defitsitnom rakhite.

Structure properties and lipid-binding ability of fibrinogen and gamma-globulins were studied in blood plasma of children with rickets. Content of cholesterol and its esters, developing complexes with fibrinogen, was found to increase simultaneously with a decrease in the phospholipids, containing in the protein fraction, under conditions of the disease. Surface charge of the proteins studied, especially of fibrinogen, was altered, thus demonstrating the distinct impairments of their structure and functions. Lipid environment appears to be of importance in functional activity of these proteins.

[Structural characteristics of integral protein-3 of rat erythrocyte membranes in hypovitaminosis D]. / Strukturnye osobennosti integral'nogo belka-3 membran érytrotsitov krys pri D-gipovitaminoze.

The amino acid composition, lipid-binding ability, the values of pK and binding capacity of negatively charged sites of the integral protein-3 from erythrocyte membranes are determined for rats in norm and under conditions of D-hypovitaminosis. Protein-3 binding of phosphatidyl choline and sphingomyelin considerably decreases, while that of cholesterol and lanosterol increases with the unchanged amino acid composition under conditions of D-hypovitaminosis. This leads to the enhancement of the protein electro-negativity as its carboxylic groups and histidine imidazole become more accessible for titration. An increase of the negative charge of protein-3 with D-hypovitaminosis is supposed to be responsible for inhibition of the anionic transport realized by it through the forces of electrostatic repulsion.

[Effect of carbostimulin on the concentration of tricarboxylic cycle metabolites, oxidative processes and antibody biosynthesis in the rat]. / Vliianie karbostimulina na soderzhanie metabolitov trikarbonovogo tsikla, okislitel'nye protsessy i biosintez antitel u krys.

Carbostimulin is studied for the effect it exerts on indices of the acid-base equilibrium of blood, content of certain tricarboxylic-cycle metabolites and free amino acids and formation of antibodies in rats. It is established that carbostimulin feeding increases the total carbon dioxide, pyruvate and lactate concentration in blood, the content of ammonium, glutamine and certain free amino acids being decreased. Oxidation processes in the liver mitochondria and biosynthesis of antibodies in experimental animals are shown to be more intensive than in the control ones.

[Changes in the biosynthesis of acid-soluble collagen in the skin of rats with amino acid imbalances in their diets]. / Ob izmeneniiakh v biosinteze kislotorastvorimogo kollagena kozhi krys pri disbalanse aminokislot v ratsione.

The feeding of excessive leucine and phenylalanine doses to rats against a background of protein deficiency is shown to cause changes in the liver tRNA aminoacylation as well as in the synthesis of acid-soluble skin collagen differing from the normal level in the amino acid composition, elution profiles and content of disulphide groups.

[Disorders of amino acid pool in the blood and gastric mucosa in patients with peptic ulcer]. / Narushenie aminokislotnogo fonda syvorotki krovi i slizistoi obolochki zheludka u bol'nykh iazvennoi bolezn'iu.

It has been demonstrated that peptic ulcer patients manifest hypo- and dysaminoacidemia and a dramatic increase in the amino acid pool of the gastric mucosa which are accounted for by neurogenic dystrophy leading to catabolic orientation of the processes not only in the mucous membrane of the gastroduodenal zone but also in other organs with a high level of protein synthesis, particularly in the liver. Based on the coefficients that determine amino acid transformation in the liver and analysis of the blood serum content of replaceable amino acids, peptic ulcer patients were discovered to have marked impairment of the amino acid-forming function of the liver.

[Possible ways of correcting disorders of the amino acid content of the blood serum and gastric mucosa during treatment of peptic ulcer]. / Vozmozhnye puti korrektsii v protsesse lecheniia narushennogo aminokislotnogo sostava syvorotki krovi i slizistoi zheludka u bol'nykh iazvennoi bolezn'iu.

Investigations made by the authors permit the conclusion that in order to correct the disturbed amino acid content of the gastric mucosa and blood serum, mirroring the trends in the catabolic processes occurring in the body and disorder of liver amino acid-forming function, it is necessary to include the drugs eliminating the causes of the disorders (e. g. neurogenic dystrophy), stimulants of protein synthesis and amino acid preparations as structural material for proteins into the complex of treatment measures.

[Effect of tryptophan excess in a diet on amino acid composition of skin collagen and on an initial stage of protein biosynthesis in rat liver]. / Vliianie izbytka triptofana v ratsione na aminokislotnyi sostav kollagena kozhi i nachal'nyi étap biosinteza belka v pecheni krys.

Protein deficiency and tryptophane load against its background lead to the acid-soluble collagen synthesis in the rat skin. The amino acid composition of the collagen differs from the norm. This is accompanied by changes in the free amino acid pool of blood serum and liver, under tryptophane load the free amino acids pool of the liver increasing twice as high. At the same time protein deficiency increases and tryptophane load decreases the level of tRNA amino acylation with tryptophane in the animal liver. Thus, protein deficiency and tryptophane load against its background cause deep changes in the protein biosynthesis.

[Acid-soluble collagen in the skin of rats who received a tryptophan load and were kept on a protein-free diet]. / Kislotorastvorimyi kollagen kozhi krys pri nagruzke triptofanom na fone bezbelkovogo ratsiona.

Crystalline preparations of acid-soluble collagen of rat skin in norm and with tryptophan load against a background of the protein-free diet were fractionated by differential salting out using NaCl in concentrations corresponding to precipitation zones of collagen 1,3 and 4. Amino acid composition, electrophoretic mobility in polyacrylamide gel, profiles of elution from CM-cellulose, content of the carbohydrate component and--S--S-bonds were studied in proteins of the mentioned fractions and in the precipitate insoluble after the pepsin action. Essential differences as compared to the normal level in the amino acid composition and elution profiles were detected in the fraction corresponding to collagen I. Quantitative changes in the carbohydrate component and--S--S-bonds occur due to the fraction inaccessible to the persin action.

[Amino acid composition of preparations acid-soluble skin collagen and free amino acids in rat serum under loading with valine and methionine]. / Aminokislotnyi sostav preparatov kislotorastvorimogo kollagena kozhi i svobodnye aminokisloty syvorotki krovi krys pri nagruzke valinom i metioninom.

The valine and methionine loading against a background of protein-free diet evokes interrelated changes in amino acid composition of acid-soluble skin collagen preparations and free amino acids pool of blood serum in rats. The isolated collagen preparations also differ essentially from the normal preparations in the content of disulphide groups and elution profiles.

[Amino acid composition and subunit structure of rabbit muscle aldolase in experimental atherosclerosis]. / Aminokislotnyi sostav i sub"edinichnaia struktura al'dolazy iz myshts krolikov v usloviiakh éksperimental'nogo ateroskleroza.

Under atherosclerosis the fractions corresponding to alpha-subunits are focused at a more alkaline pH than the same fractions in the norm. The curve of the enzymic activity of the fractions with atherosclerosis is higher. beta-subunits of aldolase from muscles of intact rabbits and those with sclerosis are identical in the amino acidic composition. In the enzyme alpha-subunits under conditions of atherosclerosis the content of lysine, serine, glycine, valine gets higher. On the basis of the previous research which reveals peptide having no analogs in the norm in the C-terminal fragment of aldolase molecule an assumption is advanced that under conditions of atherosclerosis the intermediate C-terminal site of the enzyme alpha-chain changes.

[Effect of carboxylin and sodium citrate on the content of intermediate products of tricarboxylic cycle, free amino acids and urea in rabbit tissues in alloxan diabetes]. / Vliianie karboksilina i limonnokislogo natriia na soserzhanie promezhutochnykh produktov trikarbonovogo tsikla svobodnykh aminokislot i mocheviny v tkaniakh krolikov pri alloksanovom diabete.

Feeding carboxylin and sodium citrate to rabbits with alloxane diabetes, normalizes the disturbed contents of malate, alpha-ketoglutarate, oxaloacetate, citrate and pyruvate in the blood and liver of these animals restores the total content of alpha-keto-and free amino acids, increases considerably the urea content in the liver.

[Changes in chemical composition, biosynthesis and structure of secretion of intermediate area of chicken stomach with A-avitaminosis]. / Izmenenie khimicheskogo sostava, binsinteza i struktury sekreta promezhutochnoi zony zheludka tsypliat pri A-avitaminoze.

In the intermediate area of the chicken stomach with A-avitaminosis the amount of the secretion increases and its chemical composition changes sharply: the content of water, lipids, hexolamines and suphates lowers. By means of 14-C-acetate, 35S-methionine and 35S-sulphate it is established that renewal of the secretion is inhibited. The electron-microscopic examinations showed that the secret is homogenous in normalcy but with A-avitaminosis it acquires a honeycomb structure, its physicochemical properties being changed: it becomes rigid, cuticle-like. As a result there appear deep cracks reaching mucosa, which lead to formation of erosions and ulcers. An assumption is advanced that the initial disturbances of the secretion might be not related to protein component (as the ratio of amino acids in it's almost unchanged) and depend on the carbohydrate and lipid components. The hypothesis of de Luc et al. as to the transport and intermediatory function of vitamin A in biosynthesis of glycosamineglycanes, glycolipids and glycolipoproteins is questioned. Vitamin A may take part in these processes but not as an intermediator of metabolic systems but as the level of biological structures (for instance, the Golgi apparatus and others) which organize these systems and coordinate their function.