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1.
Summary 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.Department of Microbiology, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 636–639, September–October, 1976.  相似文献   

2.
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   

3.
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   

4.
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   

5.
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   

6.
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   

7.
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   

8.
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   

9.
Abstract

Aminoalkyl phosphonic compounds have many interesting biological properties: they are used as herbicides, antibiotics and enzyme inhibitors. Several approaches to the preparation of α-aminophosphonic acids have been reported. One efficient method using the schiff base of diethyl amino methylphosphonate 1 has been developped, allowing alkylation at the α carbon after deprotonation using strong bases such as LDA. In our continuing program dealing with the synthesis of unusual α-aminoacids which relies on C-C bond formation by transition metal catalyzed reactions (l), we report here a method based on the palladium-promoted alkylation of diethyl aminophosphonate schiff bases 2 and 3 with n3-allyl species 5 generated in situ from the allylic derivative 4:  相似文献   

10.
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   

11.
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   

12.
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   

13.
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   

14.
《Tetrahedron letters》1987,28(13):1377-1380
Duryne, 1, a cytotoxic metabolite which inhibits the growth of both mouse and human tumor cell lines invitro has been isolated from the marine sponge Cribrochalinadura. Its structure has been assigned by spectral methods.  相似文献   

15.
Summary In a comparison of the substrate specificity of the action of a culture ofActinomyces albus 3006 and a cell-free preparation obtained from the mycelium ofA. albus 3006, it was found that the spectrum of the action of the steroid oxidoreductase ofA. albus is broader than the spectrum of the action of the culture. Some of the factors responsible for the difference in the specificity of the action of the culture of the microorganism and the enzyme preparation are examined.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 2, pp. 100–107, 1965  相似文献   

16.
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   

17.
    
Conclusions The formation of 20-hydroxysteroid oxidoreductase with a constitutive enzyme ofActinomyces roseochromogenus is activated by certain predominantly monohydroxy derivatives of pregnane. Some steroids suppress the formation of the enzyme. Intact cells ofA. roseochromogenus and a cell-free enzyme system possess identical substrate specificities which are close to the substrate specificity of the 20-hydroxysteroid oxidoreductase of rat testes and reduce only 20-oxopregnanes with a 17-oxygen function. The specific role of the 17-oxogen function appears at the substrate-enzyme level.Khimiya Prirodnykh Soedinenii, Vol. 6, No. 1, pp. 47–52, 1970  相似文献   

18.
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   

19.
From the soft coral Antheliaedmondsoni two new diterpenoids, waixenicin-A (1) and -B (2) have been Isolated. Their structures were elucidated by1H and13C NMR analysis and the relative stereochemistry was determined by x-ray diffraction of crystalline waixenicin-B (2).  相似文献   

20.
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   

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