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1.
1. An active lipase enzyme has been isolated from the culture liquid of the fungusRhizopus microsporus, UZLT-1, by precipitation with isopropanol, gel filtration on Sephadexes G-75 and G-150, and chromatography on CM-cellulose. Some properties of the purified enzyme (optimum pH, heat stability, influence of various ions) have been studied.  相似文献   

2.
An acid form of ricin — ricin T — with a molecular weight of 58 kDa, an isoelectric point, pI, of 7.0–7.1, and a sedimentation coefficient of 4.60 S has been isolated from the seeds of the Central Asian castor-oil plantRicinus communis by gel filtration on Sephadex G-75 followed by ion exchange chromatography on DEAE- and CM-celluloses. The amino acid composition and the N-terminal amino acid residues of ricin T have been determined.Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 883–887, November–December, 1987.  相似文献   

3.
Lipopolysaccharides have been isolated from two R mutants of the pseudotuberculosis microbeYersinia tuberculosis, serovar VA. Mild acid hydrolysis followed by gel filtration on Sephadex G-25 gave the core oligosaccharides OS I and OS II. Complete acid hydrolysis showed that OS I consisted of residues of D-galactose, G-glucose, two heptoses (D-glycero-D-mannoheptose and L-glycero-D-mannoheptose), and D-glucosamine in a ratio of 1:2.5:4:1, while OS II consisted of residues of D-glucose, heptoses, and D-glucosamine in a ratio of 1:2.5:0.2. On the basis of the results of monosaccharide analysis, methylation, Smith degradation, etc., a partial structure of the core oligosaccharide of the LPS ofY. pseudotuberculosis has been put forward.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 751–755, November–December, 1985.  相似文献   

4.
A new method has been developed for obtaining individual protamines which is based on the chromatographic separation of an ultrasonically treated nucleoprotamine solution. The separation of the nucleoprotamine from the gonads of the Caspian sturgeonAcipenser stellatus on CM-Sephadex G-25 led to the isolation of three fractions. Analysis showed that two fractions contained homogeneous protamine — stellins A and B. The third fraction contained nonprotamines and DNA.Moscow Technological Institute of the Meat and Dairy Industry. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 378–381, May–June, 1985.  相似文献   

5.
Summary 1. A chromogenic specific substrate for neutral proteinases — 2,4-dinitrophenylglycylglycyl-L-valyl-L-arginine — has been synthesized.2. A method has been developed for determining the activity of neutral proteinases in enzyme preparations with the use of this substrate which is based on the spectrophotometric determination of DNP-glycylglycine formed on the cleavage of the glycyl-valyl bond in the substrate.3. The applicability of the method to the determination of thermolysin and of the neutral proteinase fromBacillus subtilis has been shown.All-Union Scientific-Research Institute of the Genetics and Breeding of Industrial Microorganisms, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 75–80, January–February, 1976.  相似文献   

6.
The influence of a number of factors on the extraction of urease from the seeds of the watermelonCitrullus vulgaris Schrad. has been investigated by the method of mathematical planning of experimental work. On the basis of the results obtained, using the method of steepest ascent, the optimum conditions of the extraction process ensuring the maximum specific activity of the enzyme have been determined.Kharkov Scientific-Research Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 113–116, January–February, 1980.  相似文献   

7.
Summary The enzyme L-asparaginase fromE. coli has been included in polyacrylamide gel, and some of its properties have been investigated: stability, pH dependence, heat stability, Km. It has been shown that the enzymegel obtained has a better stability then the native enzyme.Institute of Organic Synthesis, Academy of Sciences of the Latvian SSR, Riga. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 382–384, May–June, 1976.  相似文献   

8.
The lipopolysaccharides ofYersinia enterocolitica, serovars 0:7.8 (strain 106) and 0:19.8 (strain 842), isolated from the microbial mass by phenol-water extraction, contained residues of L-fucose, 6-deoxy-D-gulose, D-mannose, D-galactose, D-glucose, D- and L-glycero-D-mannoheptoses, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, and 2-keto-3-deoxyoctonic acid (KDO). The polysaccharides obtained by mild acid hydrolysis of the lipopolysaccharides followed by gel filtration on Sephadex G-50 were a mixture of the O-specific polysaccharide and the core, which could not be separated even by repeated rechromatography because of the comparability of their molecular masses. On the basis of the results of monosaccharide analysis, methylation, Smith degradation, and partial hydrolysis, a structure has been suggested for the repeating unit of the O-specific polysaccharides of the lipopolysaccharides ofY. enterocolitica of the serovars studied.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, USSR Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 763–770, November–December, 1989.  相似文献   

9.
Summary 1. A method of isolating and purifying an intracellular lipase of the fungusRhizopus microsporus, UzLT-1, has been described.2. Some properties of the purified enzyme have been studied and it has been shown that the intracellular lipase differs from the extracellular lipase in its pH optimum and electrophoretic mobility.3. The presence of sodium chloride (0.06 M) in the reaction mixture raises the heat stability of the purified lipase.Division of Microbiology, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 566–570, July–August, 1977.  相似文献   

10.
Summary 1. By rechromatography on sulfoethyl-Sephadex C-50, an electrophoretically homogeneous preparation of cholinesterase has been obtained from the venom ofNaja oxiana Eichwald.2. The activity of the cholinesterase isolated depends on the concentration of the enzyme and the time and temperature of incubation, and also on the pH. The following must be considered the optimum conditions: time of incubation of the enzyme with the substrate 20–30 min, pH 8.0–8.5, temperature 37–38°C.3. Diisopropyl phosphorofluoridate (DIPF) in a concentration of 2 µM completely suppresses the activity of the cobra venom cholinesterase.4. The venom cholinesterase hydrolyzes acetylcholine chloride and acetylthiocholine bromide but has no effect on butyrylthiocholine bromide, in which respect it resembles the true cholinesterases.5. Preparations of cobra venom cholinesterase do not possess a lethal action and do not potentiate the activity of the neurotoxins of the same venom.Institute of Biochemistry, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 783–789, November–December, 1972.  相似文献   

11.
A method for immobilizingE. coli L-asparaginase on a copolymer of vinylpyrrolidone and acrolein has been developed and optimized. The influence on the nature of the modification of the number of acrolein residues in the copolymer has been established. The enzymatic and some physicochemical properties of the immobilized forms of the enzyme obtained have been studied.A. Kirkhenshtein Institute of Microbiology, Academy of Sciences of the Latvian SSR, Riga. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 562–565, July–August, 1988.  相似文献   

12.
Summary 1. It has been shown that the values of Km for the esterase activity of elastase ofActinomyces rimosus and for pancreatic elastase are of the same order of magnitude.2. The elastase ofActinomyces rimosus, unlike the pancreatic enzyme, is capable of hydrolyzing only the methyl ester of N-acetyltrialanine, and not the mono and di derivatives.3. It has been found that in the initial stage of the hydrolysis reaction it is mainly the ester bonds that are cleaved.Institute of Molecular Biology, Academy of Sciences of the USSR, Moscow. N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 693–695, September–October, 1977.  相似文献   

13.
A wide range of highly active nucleotides containing tritium labels in the heterocycle nucleus and ribose residue has been synthesized with the aid of an enzyme preparation fromE. coli, starting from tritium labeled nitrogen bases and ribose. In individual cases, the complex enzyme preparation was modified by the addition of nucleotide kinases or phosphatases.V. G. Khlopin Radium Institute and Biological Scientific Research Institute, A. A. Zhdanov Leningrad State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 258–264, March–April, 1988.  相似文献   

14.
The influence of a number of bivalent metals on the activity ofStreptomyces atratus glucose isomerase has been studied. Mg2+ ions are activators and Co2+ ions are stabilizers of the glucose isomerase activity. The effective kinetic parameters for the action of the enzyme have been determined.Institute of Microbiology, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 838–842, November–December, 1991.  相似文献   

15.
A highly purified glucose isomerase with a specific activity 23.5 times greater than that of a homogenate of the mycelium has been obtained fromStreptomyces atratus by methods of homogenization from the freeze-dried biomass, heat treatment (70°C, 10 min), ion-exchange chromatography, and gel filtration. The yield of enzyme on the initial biomass was 51.8%. The molecular mass of the enzyme has been determined by various methods as 160 kDa but in the presence of sodium dodecyl sulfate in thin-layer PAG it amounts to 40 kDa.Institute of Microbiology, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 524–528, July–August, 1990.  相似文献   

16.
    
A new alkaloid — leuconine — has been isolated from the epigeal parts ofAconitum leucostomum andA. septentrionale, and its structure has been established on the basis of spectral characteristics.Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 538–540, September–October, 1992.  相似文献   

17.
The isolation from the plantDipthychocarpus strictus (Cruciferae) of the optically active base diptaline, identified as N-(11-methylsulfinylundecyl)urea, has been reported [1]. A synthesis of the racemic form of this alkaloid has now been achieved.Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 102–105, January–February, 1992.  相似文献   

18.
The molecular mass (Mr) of highly purified glucose isomerase fromStreptomyces atratus has been determined. The native glucose isomerase, which has affinity for xylose, consists of an oligomeric protein containing 1552 amino acid residues and formed of four subunits. The enzyme is stable in the range of temperatures from 40 to 80°C and at pH values of from 6.0 to 11.0.Institute of Microbiology, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 833–837, November–December, 1991.  相似文献   

19.
Summary The physicochemical properties of the oils of the seeds of seven plants of the family Cruciferae —Cakile maritima, Sisymbrium altissimum, Sisymbrium Loeselii, Descurainia Sophia, Erysimum cheiranthoides, Brassica amoracioides andCrambe pontica — have been studied and their fatty acid compositions have been determined. The results obtained showed no marked differences from those given in the literature.Zaporozhe Medical Institute. Ukrainian Scientific-Research Institute of the Oils and Fats Industry. Zaporozhe Oils and Fats Combine. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 15–18, January–February, 1973.  相似文献   

20.
Two new alkaloids — umbrofine and 6-acetylumbrofine — have been isolated fromAconitum umbrosum, and their structures have been established on the basis of spectral characteristics.Institute of Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedenini, No. 1, pp. 73–77, January–February, 1993.  相似文献   

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