[A comparative study of the effect of inhibitors of microbial origin on different alpha-glucosidases]. / Sravnitel'noe izuchenie deistviia ingibitorov mikrobnogo proiskhozhdeniia na razlichnye alpha-gliukozidazy.

The action of a new alpha-glucosidase inhibitor from Streptomyces sp. and Acarbose on alpha-glucosidases of various origins has been studied. Differences in specificity, efficiency, nature and type of inhibition of microbial glucosidases and some enzymes of the small intestine mucosa by the biologically active substances studied were revealed. At certain concentrations these inhibitors can be substrates for some intestinal glucosidases. It is suggested that the inhibitor from Streptomyces sp. (in combination with a diet) can be used for regulation of some disturbances in carbohydrate metabolism.

[Yeast superoxide dismutase: isolation and properties (review of the literature)]. / Superoksiddismutaza drozhzhei: vydelenie i svoistva (obzor).

Modern data are reviewed on isolation procedures and properties of superoxide dismutase from Saccharomyces cerevisiae. Properties of superoxide dismutase (SOD) from yeast and SOD from macro-organisms were compared.

[Alpha-glucosidase inhibitors of microbial origin]. / Ingibitory al'fa-gliukozidaz mikrobnogo proiskhozhdeniia.

The data on spreading of inhibitors of alpha-glucosidases with microbial origin are given. Physiochemical characteristics of acorbose--a known inhibitor of alpha-glucosidases--and new inhibitor isolated from Streptomyces sp. are given in detail.

[The effect of lipase from Penicillium sp. on the membrane fraction of the levorin-producing Streptomyces levoris]. / Deistvie lipazy Penicillium sp. na membrannuiu fraktsiiu produtsenta levorina Streptomyces levoris.

The effect of a lipase preparation from Penicillium sp. on the membranes of the levorin producer Streptomyces levoris was being studied. The enzyme preparation was found preferably to hydrolyse neutral lipids in the Str. levoris membranes, which makes it possible to use the lipase from Penicillium sp. for studying neutral lipids in microbial membranes.

[Microbial inhibitors of phospholipase C]. / Ingibitory fosfolipazy C mikrobnogo proiskhozhdeniia.

Inhibitors of the Clostridium perfringens phospholipase C were prepared from the filtrates of the culture liquids of Streptomyces saracetidus and Streptomyces species using soluble and cross-linked polyelectrolytes. The technological scheme of isolation involves ultrafiltration. The inhibitors produced by the two strains had different chemical nature. The preparation obtained from Str. saraceticus was proved to be a complex of inhibitors that were separated by gel-chromatography into a major polypeptide with a molecular weight of 5500-6500 and a low-molecular weight glycopeptide. The inhibitor obtained from Str. species was found to be a high-molecular weight protein.

[Proteolytic complex from Aspergillus terricola (review)]. / Proteoliticheskii kompleks Aspergillus terricola (obzor).

Results are presented of the studies on the proteolytic enzymes produced by the fungus Aspergillus terricola that comprise the antiinflammatory drug Terrilytin. Terrilytin was shown to be a complex of three proteolytic enzymes that contained amylase as well. Two of the proteases (proteases I and II) were of the group of serine proteases by their physico-chemical and enzymatic characteristics and might be considered as two types of the same enzyme. Protease III showed characteristics specific for metalloproteases of the microbial origin, its activity being exhibited in case of the zinc ion presence. Fibrinolytic properties of Terrilytin are associated with the ability of all the three proteases to hydrolyze fibrin and fibrinogen.

[Phospholipase C inhibitor from Streptoverticillium mycoheptinicum]. / Ingibitor fosfolipazy C iz Streptoverticillium mycoheptinicum.

Streptoverticillium mycoheptinicum, a producer of the antifungal antibiotic mycoheptin, was found to produce an inhibitor of Clostridium perfringens phospholipase C. Dynamics of the enzyme accumulation in the culture liquid filtrate was studied. A technique was developed for purification of the inhibitor, which includes adsorption, selective precipitation, ultrafiltration, gel chromatography and isoelectric focusing. The inhibitor was found to be of the peptide nature with the molecular weight of 3500-4000 and to exist in two isoforms with the isoelectric points of 8.15 and 8.50.

[Rapid method of determining beta-lactamase inhibitor activity]. / Ekspress-metod opredeleniia aktivnosti ingibitora beta-laktamazy.

A simple and rapid method for determination of the activity of beta-lactamase is described. It is based on spectrophotometric recording of the enzymatic splitting of benzylpenicillin. The method is recommended for rapid control of production of beta-lactamase inhibitors.

[Method of determining the molar concentration of proteinase inhibitors and their affinity for the enzymes]. / Metod opredeleniia moliarnoi kontsentratsii ingibitorov proteinaz i ikh srodstva k fermentam.

This paper describes a graphic method for measuring the affinity and molar concentration of proteinase inhibitors from different sources, using data on the titration of the inhibitor by the enzyme of a known molar concentration. Linearization of experimental data in the (formula; see text) coordinates makes it possible to measure the value Ki with respect to the slope of the curve and to determine the inhibitor concentration with respect to the curve intercept with the ordinate axis. The method can be used to characterize proteinase inhibitors during microbial screening and at certain purification stages.

[Lipolytic complex of Penicillium sp]. / Izuchenie lipoliticheskogo kompleksa Penicillium sp.

By gel filtration on Sephadex G-75 it has been demonstrated that the lipolytic complex of Penicillium sp. contains two active components--a high molecular weight (lipase-1) and low molecular weight component (lipase-2). Both components have been isolated by Sephadex gel-filtration and DEAE-cellulose chromatography. It has been shown by discelectrophoresis and isoelectric focusing that lipase-2 is a highly purified protein with the molecular weight of 30,000 (gel-filtration) or 29,000 (electrophoresis) and isoelectric point at pH 4.8 Lipase-1 has been found to contain large quantities of lipids. The conditions of deaggregation of a high molecular weight component have been identified to yield a new active component corresponding to lipase-2 in its gel-filtration and disc-electrophoresis properties. It has been shown that pH 7.5-8.0 and temperature 37-40 degrees are optimal for both lipase-1 and lipase-2. Activities of the two components are inhibited by Na deoxycholate and remain unchanged in the presence of Na cholate and dehydrocholate. On the basis of these findings it is concluded that lipase-1 and lipase-2 are two forms of the same enzyme.

[Composition and properties of cholesterol oxidase from Actinomyces lavendulae]. / Issledovanie komponentnogo sostava i svoistv kholesterinoksidazy Actinomyces lavendulae.

The composition of cholesterol oxidase isolated by different methods from the Actinomyces lavendulae mycelium was studied by gel-chromatography. It was shown that depending on the isolation conditions the enzyme can be detected within the complexes with different molecular weights. The values of pH, pI and Km for the isolated components were determined. The thermal inactivation of the cholesterol oxidase components at different temperature intervals was investigated.

[Isolation and characterization of lipase from Geotrichum asteroides FKM F-144]. / Vydelenie i nekotorye svoistva lipazy Geotrichum asteroides VKM F-144.

By gel chromatography on Sephadex G-75 it has been demonstrated that the culture fluid of Geotrichum asteroides VKM F-144 contains two lipolytic components, one of which, lipase 1, eluates in the free volume of the column, whereas the second component, lipase 2, eluates in the volume close to that of the egg albumin yield. The paper describes a method for lipase 2 preparation consisting of precipitation of accompanying compounds at pH 4.2, depigmentation of the supernatant on the resin PAP in the Cl-form, selective sorption of lipase on the cation exchange resin CMC and further purification of the eluate gel chromatography and Sephadex G-100 rechromatography. The molecular weight of the lipase is estimated to be 45,000 and the isoelectric point to correspond to pH 4.3. pH optimum of action of the purified enzyme, areas of its pH- and thermostability have been determined.

[pH-dependence of the esterolytic activity of terrylytine proteases]. / Zavisimost' esteroliticheskoi aktivnosti proteaz terrilitina ot pH.

The pH-dependences of the kinetic parameters of hydrolysis of alpha-N-henzoyl-L-arginine and N-benzoyl-L-tyrosine ethyl esters by terrylytine proteases I and II were studied. The experimental results proved evidence for the differences in the activities of these enzymes. The active center of protease I contains two groups with close pK values (6,5-7,0), one of which is presumably the imidazole group of histidine. The catalytic action of protease II is determined by the state of the ionizing groups with the ionization constants of about 6 and 8. The former functions in the deprotonated form, whereas the latter--in the protonated form.

[Application of the ultrafiltration method to the isolation of cholesterol oxidase of microbial origin]. / Primenenie ul'trafil'tratsionnogo metoda dlia vydeleniia kholesterinoksidazy mikrobnogo proiskhozhdeniia.

Ultrafiltration of solutions of intracellular cholesterol oxidase of Actinomyces lavendulae through semi-permeable membranes (N-vinyl pyrrolidone and methacrylate copolymers) of varying porosity and acetyl cellulase ultrafilter UAM-200 M was investigated. The ultrafiltration through membranes of both types involved both concentration and purification of cholesterol oxidase from low molecular weight protein admixtures. When copolymer membranes were used, their performance and degree of purification were higher and losses were lower than in case of UAM-200 M filter. The optimum hydrolytic mode of ultrafiltration of intracellular cholesterol oxidase through both filters was determined.

[Conditions for isolation of cholesterol oxidase from Actinomyces lavendulae mycelia]. / Izuchenie uslovii vydeleniia kholesterinoksidazy iz mitseliia Actinomyces lavendulae.

The isolation conditions, composition and certain properties of cholesterol oxidase from the mycelium Actinomyces lavendulae were studied. Selective extraction of the enzyme occurred upon the mycelium extraction by the Tween-80 containing buffer. The specific activity of cholesterol oxidase thus obtained exceeded seven-fold that of the enzyme isolated via other methods. The optimal concentration of the detergent upon extraction was 0.15%. By disc-electrophoresis it was demonstrated that the preparation isolated from disrupted cells contained, in addition to cholesterol oxidase, 16 other protein components that had no enzymatic activity whereas the Tween-80 extracted preparation included no more than 7 fractions. The study of the relationship between activity of the resultant cholesterol oxidase and the substrate concentration and pH demonstrated that optimal conditions for the enzyme action were at pH 7.0-7.5 and cholesterol oxidase concentration of 0.0316 mM.

[Effect of pH on the conformation properties and enzyme activity of alpha-amylase from Aspergillus terricola]. / Vliianie pN sredy na konformatsionnye svoistva i fermentativnuiu aktivnost' al'fa-amilazy iz Aspergillus terricola.

The effect of pH values on the conformation state of the protein globule and enzyme activity of alpha-amylase isolated from the culture liquid of the fungus Aspergillus terricola was studied. By the method of dispersion of optical rotation, it was demonstrated that together with the disordered structure the alpha-amylase macromolecule in its native form contained alpha-helix and beta-structures. With a pH change the enzyme macromolecule showed two conformational transformations: with a pH decrease from 4.0 to 2.0 alpha-helix uncoiled, and with a pH increase from 8.0 to 12.0 beta-form degraded. Hydrolytic activity of alpha-amylase was found to vary symbatically with the specific optic rotation in the above pH range.

[Isolation of lipase of microbial origin]. / Vydelenie lipazy mikrobnogo proiskhozhdeniia.

By gel chromatography and polyacrylamide gel disc-electrophoresis the component composition of the culture liquid separated from the mycelium was investigated. After elution from Sephadex G-75 column lipase activity was concentrated in one peak. Out of 13 electrophoretic mobile protein components only one split trioleate. The paper describes a method to isolate lipase from the native solution of the produced which involves enzyme precipitation at 40% saturation of the native solution with ammonium sulphate, dialysis of the resultant concentrate and selective sorption of pigment and protein admixtures on the cellulose anion exchanger. The method maker it possible to obtain a highly purified lipolytic enzyme with a specific activity of up to 15 000 lu/mg protein and to provide its 35--40% yield.

[Comparative study of the properties of lipase of microbial origin]. / Sravnitel'noe izuchenie svoistv lipaz mikrobnogo proiskhozhdeniia

A comparative study of properties of lipases of microbial origin has shown that the pH optimum of the enzymes from Geotrichum asteroides and Penicillium sp. is at pH 7.5 and 5.0, respectively. Lipase from Geotrichum asteroides appears more resistant to high temperatures and pH changes than the enzyme from Penicillium sp. Both enzymes split selectively vegetable oils, especially cotton and sunflower oils. Na cholate and deoxycholate at a concentration of 0.05-0.4% act as hydrolysis activators, particularly with respect to Geotrichum lipase. Na dehydrocholate does not show this effect.

[Preparative isolation of terrilytin components and study of their enzymatic properties]. / Preparativnoe vydelenie komponentov terrilitina i izuchenie ikh fermentnykh svoistv

By ion-exchange chromatography the composition of the fibrinolytic enzyme from Aspergillus terricola-terrilytine-was studied. The preparation contained five components that differed in their substrate specificity. Three of the components and proteolytic and fibrinolytic activities. The isolated fractions were examined with respect to their pH stability, pH optima (casein, hemoglobin and fibrin used as substrates), fibrinolytic and fibrinohenolytic activities.

[Permeability of acetylcellulose ultrafiltration membranes with regard to biologically active substances]. / Pronitsaemost' atsetiltselliuloznykh ul'trafil'tratsionnykh membran po otnosheniiu k biologicheski aktivnym veshchestvam

The permeability of standard Soviet ultrafiltration membranes prepared from cellulose acetates was investigated with respect to biologically active substances (hemoglobin, trypsin, ribonuclease, vitamin B12, hydroxytetracycline) and inorganic salt (KH2PO4). The arrest of a substance by a membrane of a certain structure depended primarily on the size of the substance macromolecule in the solution. The filtration rate was related to the membrane type, pressure gradient and composition of the filtered solution. Potential use of the tested membranes is described.