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11.
R. V. Mikhailova A. G. Lobanok Zh. F. Shishko M. I. Yasenko 《Applied Biochemistry and Microbiology》2000,36(2):169-172
Effects of conditions ofPenicillium funiculosum G-15 cultivation on the production of extracellular glucose oxidase were studied. The data showed that surface and submerged
methods of cultivation can be used for obtaining a glucose oxidizing enzyme. The optimum conditions for submerged cultivation
(25°C., initial pH 5.0, and aeration of 3 1/1 per min) and surface cultivation (temperature 25°C and initial pH 4.0) providing
the maximum levels of glucose oxidase synthesis were determined. 相似文献
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M E Krakovski? A Kh Ashirmetov Zh Iu Iuabova 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1991,(3):30-37
The microsomal cytochrome content and enzyme activity has been determined in liver, kidney, lungs and intestinal mucous from guinea pig males which were injected 25% ethanol intraperitoneally at a dose of 2 g per 1 kg of body mass. The changes in cytochrome P-450 and b5 content, amidopyrine-N-demethylase, aniline hydroxylase, p-nitrophenol hydroxylase. NADP.H-cytochrome-c-reductase activities in investigated organs of the animals have been found depending on the ethanol intoxication period (for 3, 6 or 14 days). Changes of the same type in microsomal enzyme activities have been discovered in liver, lungs and intestine, but not in kidney that is accounted for the substrate specificity and inducibility of the cytochrome P-450 some forms in extrahepatic tissues. 相似文献
14.
Biophysics - Abstract—We consider a previously proposed method for encapsulation of enzymes, which employs the layer-by-layer adsorption of oppositely charged polyelectrolytes onto composite... 相似文献
15.
E N Goncharova S S Timoshin Zh D Bespalova S G Vyborov 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(6):647-649
The effect of atrial natriuretic factor (ANF) synthetic linear truncated analogues AP-H-6-OH and AP-FOR-6-OH on corneal, skin, duodenum and colon epithelium proliferation has been studied on male rats. The epithelium mitotic activity and DNA synthesis were evaluated 4 and 24 h after intraperitoneal injection of 10 or 100 micrograms/kg peptides. In a dose of 10 micrograms/kg both ANF synthetic analogues inhibited proliferation processes in corneal epithelium, but activated the DNA synthesis in duodenum and colon epithelium. AP-FOR-6-OH (10 micrograms/kg) decreased the mitotic activity of skin epithelium and increased the silver grain density over the cell nuclei at the same time. 100 micrograms/kg ANF analogues stimulated cell mitogenesis in all organs studied. According to the data obtained ANF linear truncated analogues influence on epithelium proliferation is similar to effector of previously studied cyclic atriopeptin AP II. 相似文献
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N S Egorov Zh K Loriia S N Vybornykh R Khamrun 《Prikladnaia biokhimiia i mikrobiologiia》1986,22(1):107-111
The effect of the culture medium composition on the bacitracin synthesis and sporulation in Bacillus licheniformis 28 KA was being studied. During the producer's growth on a medium with tripton a biphasic pattern of the process was observed, i.e. a rapid growth of the bacterial biomass was accompanied by the production of insignificant amounts of the antibiotic. The maximum efficiency of the antibiotic synthesis coincides with the end of the exponential growth phase and the onset of sporification. The efficiency of sporification amounts up to 95% when the above mentioned medium is used. The substitution of glutamate for trypton results in a dramatic deceleration of the bacterial growth and biomass accumulation, and the process of the antibiotic biosynthesis ceases to be biphasic, i. e. the antibiotic is synthesized during the trophophase. Under the conditions when the antibiotic production drops to zero by the middle of the exponential growth phase, sporulation is virtually suppressed. 相似文献
19.
Some properties of hexameric purine nucleoside phosphorylase II (EC 2.4.2.1) from Escherichia coli K-12 were studied. The enzyme obeys the Michaelis-Menten kinetics with respect to purine substrates (Km for inosine, deoxyinosine and hypoxanthine are equal to 492, 106 and 26.6 microM, respectively) and exhibits negative kinetic cooperativity towards phosphate and ribose-1-phosphate. The Hill coefficient is equal to approximately 0.5 for both substrates. Hexameric purine nucleoside phosphorylase II is not a metal-dependent enzyme; its activity is inhibited by Cu2+, Zn2+, Ni2+ and SO4(2-). The enzyme is the most stable at pH 6.0; it contains essential thiol groups. All substrates partly protect the enzyme against inactivation by 5.5'-dithiobis(2-nitrobenzoic acid) and heat-inactivation and, with the exception of phosphate-against inactivation by p-chloromercuribenzoate. Hypoxanthine, especially in combination with phosphate, afford the best protection against inactivation. 相似文献
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