Inorganic pyrophosphatases (PPases) catalyze an essential reaction, namely, the hydrolysis of PP, which is formed in large quantities as a side product of numerous cellular reactions. In the majority of living species, PP hydrolysis is carried out by soluble cytoplasmic PPase (S-PPases) with the released energy dissipated in the form of heat. In part of this energy can be conserved by proton-pumping pyrophosphatase (H-PPase) in the form of a proton electrochemical gradient for further ATP synthesis.
View Article and Find Full Text PDFA novel technique for targeted stable multiplication of a specific long E. coli chromosome fragment was developed. The method is based on the coordinated functioning of λ and φ80 bacteriophage site-specific recombination and integration systems.
View Article and Find Full Text PDFBackground: In the L-histidine (His) biosynthetic pathway of Escherichia coli, the first key enzyme, ATP-phosphoribosyltransferase (ATP-PRT, HisG), is subject to different types of inhibition. Eliminating the feedback inhibition of HisG by the His end product is an important step that enables the oversynthesis of His in breeding strains. However, the previously reported feedback inhibition-resistant mutant enzyme from E.
View Article and Find Full Text PDFThe stimulating effect of light-isotope water on microbial growth was demonstrated in bacterial culture Pseudomonas esterophilus. Nutrient medium was prepared of mineral salts and ethyl acetate as a source of carbon dissolved in light-isotope water with ppm 35 and 70; the control medium contained same components dissolved in distilled water. The investigation showed an increase in the number of bacterial cells in the exponential stage of growth in static culture in light-isotope water as compared with the control.
View Article and Find Full Text PDFOne of the formidable problems of exploration missions is creation of autonomous water-closed life support systems. Sources of water for regeneration could be various water-containing human wastes including urine, the most chemically contaminated liquid. Prior to physical/chemical regeneration, urine first must be decontaminated in order to put a stop to microbiological processes that form harmful and volatile compounds contaminating condensate and drastically reducing the service life of afterpurifucation filters.
View Article and Find Full Text PDFTested was an idea to eliminate six harmful admixtures reside in a surrogate of atmospheric condensate of closed habitats by a cultivated bacterial association. The purpose was to select members of the bacterial associations that would assimilate acetone, acetic acid, ethanol, ethyl acetate, methylamine and ammonia as free, so immobilized on insoluble cellular polyvinylformal. The resulted association of three bacterial species showed the ability to transform into end products a six-component surrogate of atmospheric condensate.
View Article and Find Full Text PDFBacterial strains were screened to transform to end-products (carbon monoxide and water) elevated concentrations of acetone, acidic acid, and ethanol in a biocatalyst with an immobilized bacterial association cultivated on solid foam polyvinyl acetate (FPVA). The innocuous association amalgamated Paracoccus denitrificans VKM V-1324, Pseudomonas esterophilus VKM V-1736D and Achromobacter parvulus VKM V-1541D. The biocatalyst was tested with the help of classic methods and equipment for microbes cultivation.
View Article and Find Full Text PDFChemical and microbial safety will be one of the major functions of a closed eco-system aboard piloted interplanetary vehicle. Methods for decontamination and preservation of water-containing human wastes (WHW) should be developed on the assumption that WHW are a labile biochemical system biological and chemical processes of which are intricately dependent on preservatives, regenerative water quality, structural material off-gassing, and methods of WHW collection, storage, and management.
View Article and Find Full Text PDFPolymeric particles formed by stearoyl-poly-N-vinylpyrrolidone (PVP-stear) of M(n) = 2600 were obtained in aqueous solution, and their shape and size distribution were characterized. The size of the particles was shown to decrease with an increase in the ionic strength of the solution. Interaction of PVP-stear and its aggregates with model proteins (Bowman-Birk soybean proteinase inhibitor (BBI) and its hydrophobized derivatives) was studied.
View Article and Find Full Text PDFThe lipidized derivatives of Bowman-Birk soybean protease inhibitor (BBI) containing one to three oleoyl groups were synthesized and characterized. The (ole)(1)- and (ole)(2)BBI were demonstrated to have 200- and 100-fold higher uptake into Caco-2 cell monolayers compared to native BBI. The acylated BBI had increased affinity to elastase-like proteases.
View Article and Find Full Text PDFBiochemistry (Mosc)
December 2002
The effect of acylation of Bowman-Birk soybean proteinase inhibitor (BBI) by derivatives of various unsaturated fatty acids on inhibition of trypsin, alpha-chymotrypsin, and human leukocyte elastase was investigated. Inhibition (K(i)) and kinetic (k(ass), k(diss)) constants of interaction between proteases and acylated BBI derivatives were determined. For mono-, di-, and triacylated BBI derivatives, insertion of two oleic residues into the BBI molecule was demonstrated to be more potent for exhibiting antiproteinase activity.
View Article and Find Full Text PDFBiochemistry (Mosc)
April 2001
A procedure was developed for acylation of Bowman-Birk soybean proteinase inhibitor (BBI) by N-hydroxysuccinimide esters of oleic, linoleic, and alpha-linolenic acids in a dimethyl sulfoxide-dioxane-pyridine mixture. BBI derivatives containing two acylated amino groups were prepared with high yield. The use of the reversible modifier citraconic anhydride in the first stage of synthesis permitted the synthesis of hydrophobized BBI derivatives retaining high antitrypsin and antichymotrypsin activities.
View Article and Find Full Text PDFThe effect of modification of basic pancreatic trypsin inhibitor (BPTI) by derivatives of fatty acids (oleic, stearic) on the inhibition of bovine trypsin and human leukocyte elastase (HLE) was studied. Kinetic constants of interaction with trypsin and inhibition constants of both enzymes were determined. Hydrophobization of BPTI had virtually no effect on its high affinity for trypsin.
View Article and Find Full Text PDFThe results of studies on producing the biocatalyst based on catalase immobilized in the fibers from triacetate are presented. The catalase producer is Penicillium fungus. Catalase was produced by precipitation with the use of ethyl alcohol from the cultural fluid with separate and unseparate mycelium.
View Article and Find Full Text PDFA procedure was developed for the modification of basic pancreatic trypsin inhibitor (BPTI) by N-hydroxysuccinimide esters of oleic and stearic acids in a DMSO-DMF-dioxane-pyridine mixture with a temporary citraconyl protection of the amino group belonging to its active site. The BPTI derivatives containing from one to three acylated amino groups were obtained. It was shown that the hydrophobized BPTI with one amino group modified retained practically the full activity of the native inhibitor.
View Article and Find Full Text PDFPatol Fiziol Eksp Ter
October 1995
The preventive and therapeutical effects of oxytetracycline hydrochloride, 10 mg/kg b.w., and chingamine, 50 mg/kg b.
View Article and Find Full Text PDFFarmakol Toksikol
August 1979
Tests on albino rats brought evidence that the antineoplastic drug phosphemide, administered to the animals in doses of 10 mg/kg daily for 7 days reduces the glycogen content in the liver on the 5th day of investigation. In the heart, skeletal muscles, kidneys and spleen no changes in the glycogen were noted. Phosphemide produced morphological changes in the spleen and kidneys.
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