[Precipitated, coprecipitated, and carbon-mineral sorbents for isolation of extracellular catalase from Penicillium piceum F-648]. / Osazhdennye, soosazhdennye i uglemineral'nye adsorbenty dlia vydeleniia vnekletochnoi katalazy Penicillium piceum F-648.

The abilities of various sorbents to adsorb catalase (CAT; EC 1.11.1.6) from filtered culture liquid (FCL) of the fungus Penicillium piceum F-648 were compared. Potassium phosphate, hydroxyapatite (HAP), and coprecipitated sorbents containing calcium phosphate and magnesium hydroxide adsorbed extracellular CAT more efficiently than aluminum oxide, aluminum phosphate, or quartz sand. The enzyme was isolated from FCL of Penicillium piceum with the use of HAP and a binary coprecipitated sorbent, Ca3(PO4)2 + Mg(OH)2, 1:1 (CM). The CAT(CM) sample contained the least amount of protein admixture. Its spectra had absorption maximums at 279.6, 406.8 (Soret band), 540, 585, 636, and 703 nm and negative molar ellipticity minimums at 207 and 210-214 nm. The kinetic indices of the samples (KM, Vmax:KM, and specific activity) were intricately dependent on protein concentration in the reaction mixture. In dilute solutions, the KM and specific activities of CAT(CM) and CAT(HAP) equaled 667 and 137 mM; 300.9 x 10(4) and 30.0 x 10(4) U/mg protein, respectively. The effective velocity constants of inactivation of CAT(HAP), CAT(CM), and FCL in the reaction of H2O2 decomposition increased dramatically after dilution of samples. In the infinitely dilute solution, they were 4.30 x 10(-2), 6.46 x 10(-2), and 1.12 x 10(-2), respectively.

[Quartz sand as an adsorbent for purification of extracellular glucose oxidase from Penicillium funiculosum 46.1]. / Kvartsevyi pesok--sorbent dlia vydeleniia vnekletochnoi gliukozooksidazy Penicillium funiculosum 46.1.

The procedure of purification of extracellular glucose oxidase (GO, EC 1.1.3.4) from culture-liquid filtrate (CLF) of the fungus Penicillum funiculosum 46.1 using alluvial quartz sand as an adsorbent has been developed. The modification of sand by changing the charge and polarity did not lead to a significant increase in its adsorption capacity towards GO. The effectiveness of sand and aluminum oxide, used as sorbents for isolation of GO from CLF, was compared. Glucose oxidase, isolated from CLF by adsorption on sand, exhibited a greater catalytic activity compared to the enzyme specimens obtained by column chromatography on CLF. Sand adsorbed GO from P. funiculosum 46.1 more effectively than aluminum oxide. It is concluded that sand may be used for fractionation of partly purified GO.

[Complex-formation of phospholipase A2 with fragments of nucleic acids and approaches to its elimination]. / Kompleksoobrazovanie fosfolipazy A2 s fragmentami nukleinovykh kislot i sposoby ego ustraneniia.

Formation of phospholipase A2 stable complexes with nucleic acid fragments was observed upon the isolation of the enzyme from pig pancreas. This complex could be disrupted by neither DNA precipitation with protamine chloride and cetyltrimethylammonium bromide nor chromatography on DEAE-cellulose and CM-cellulose or hydroxyapatite. The treatment of the complexes with 1 M acetic acid followed by gel-chromatography on Sephadex G-75 in 1 M acetic acid resulted in complete separation of active phospholipase A2 from DNA fragments.

[The diagnostic and prognostic value of determining the content of beta 2-microglobulin in the blood and urine of potential kidney donors]. / Diagnosticheskaia i prognosticheskaia tsennost' opredeleniia soderzhaniia beta 2-mikroglobulina v krovi i mochi potentsial'nykh donorov pochek.

The paper provides the results of a clinical observation of 20 potential kidney donors having various agonal periods. Significant changes in beta 2-microglobulin levels in blood and urine depending on the agonal duration were established. The nature of the changes in biological fluids suggest their significance in early diagnosis of renal ischemic lesions during the agonal period, as well as in the prognostic assessment of organ viability and functional adequacy.

[A radioimmunologic test system for determining beta 2-microglobulin in human blood serum and urine]. / Radioimmunologicheskaia test-sistema dlia opredeleniia beta 2-mikroglobulina v syvorotke krovi i moche cheloveka.

The authors described a radioimmunoassay developed for the determination of beta 2-microglobulin (beta 2-M) concentration in human serum and urine using 125I-labeled beta 2-M. This method permitted the determination of beta 2-M concentration within 0.5-50 mg/l in the blood serum and within 0.02-50 mg/l in urine. beta 2-M concentration determined by this assay, was 1.71 +/- 0.58 mg/l in the blood serum and 0.097 +/- 0.32 mg/l in the urine of healthy persons.

[Changes in the methylated sequences and molecular population of wheat DNA during germination]. / Izmenenie metiliruemykh posledovatel'nostei i molekuliarnoi populiatsii DNK pshenitsy pri prorastanii.

The fractions of unique (Cot less than 405), moderately (Cot=0.13--405) and highly reiterated (Cot less than 0--0.13) sequences were isolated from DNA of wheat seeds and 3 day old seedlings, and GC content, amount of 5-methylcytosine and its distribution among various pyrimidine isostichs in the fractions isolated were studied. Different in Cot value DNA fractions from seeds or from seedlings are similar in GC content and in all other characteristics studied. Seed DNA differs from DNA of seedlings in the content of pyrimidine isostichs from the respective fractions of reiterated sequences. Pronounced differences in the amount of pyridmidine clusters with various base composition in the corresponding fractions of DNA from seeds and seedlings were found. These differences in the frequencies of respective pyrimidine clusters from DNA of seeds and seedlings may be considered as being a result of changes in the molecular population of wheat DNA on germination. The seed and seedling DNA differ significantly in the 5-methylcytosine content in the respective pyrimidine isostichs isolated from unique sequences. In the seedling DNA some other nucleotide sequences are to be methylated as compared to DNA of dormat seeds. Thus, on germination some changes occur in DNA methylation as well as in the genome organization.

[Content of 5-methylcytosine in various families of repeating sequences of DNA in some higher plants]. / Soderzhanie 5-metiltsitozina v raznykh klassakh povtoriaiushchikhsia posledovatel'nostei DNK nekotorykh vysshikh rastenii.

Three families of repeating DNA sequences from 6 higher plants species are isolated. It is found that DNAs of plants examined at the same developmental stages differ considerably in the content of fractions with different repetition frequency of nucleotide sequences. The content of non-repeating sequences in the genome of the plants varies from 23.8 to 41.4%, the differences in the content of highly repeating fractions are less expressed (from 20.3 to 29.4% of the genome). The ratio of fractions changes considerably during ontogenesis: DNA of seeds contains more highly repeating sequences than DNA of seedlings. Fractions of nucleotide sequences with different repetition frequency, isolated from the same DNA, are little distinguished in the GC-pair content, and are characterized by a relatively high content of 5-methylcytosine: the methylation degree of cytosine is at least 17%. However, the degree of cytosine methylation is increased in fractions with high content of copies per genome in seedlings and leaves DNA of all the plants studied. The content of 5-methylcytosine in highly repeating fractions is 12% higher than in non-repeating sequences. Seed DNAs have some other distribution of 5-methylcytosine in different fractions: the degree of cytosine methylation in non-repeating and highly repeating sequences is practically the same.

[Changes in base composition and molecular population of wheat DNA on germination]. / Izmenenie nukleotidnogo sostava i molekuliarnoi populiatsy DNK pshenitsy pri prorastanii.

Germination of wheat seeds results in small changes of the GC content of total DNA (from 47.5 to 49.0 mole %): at the same time the amount of 5-methylcytosine in seeds 10 hours after wetting and at day 3 of germination significantly decrease (from 6.0 to 5.4 and 5.2 mole %, respectively). The wheat genome is methylated in non-uniform fashion: moderute repeats (less than a hundred copies, interval Cot = 0,12 . 10(2)-420) possess the maximal amount of 5-methylcytosine, while the unique sequences (Cot greater than 420) have the lowest 5-methylcytosine content. Methylation of highly reiterated sequences (Cot less than 0,8 . 10(-2) is similar to that of the total DNA. At day 3 of germination the amount of 5-methycytosine in all DNA fractions is lower as compared with these fractions isolated from DNA of dormant seeds. This is probably due to (1) diminution in the amount of reiterated sequences with high 5-methylcytosine content and (2) to lowering of DNA methylation level in germinating seeds. Changes in DNA methylation may be associated with the regulation of gene activity in the differentiating plant cells at various stages of ontogenesis.

[DNA degradation during standard alkaline of thermal denaturation]. / Degradatsiia DNK pri standartnoi shchelochnoi ili termicheskoi denaturatsii

Essential degradation 8 DNA (up to 10 per cent) with liberation of acid-soluble fragments takes place on the standard alkaline (0,01 M sodium phosphate, pH 12, 60 degrees, 15 min) or thermal (0.06 M sodium phosphate buffer, pH 6.8, 102 degrees C, 15 min) denaturation. This degradation is more or less selective: fraction of low molecular weight fragments, isolated by hydroxyapatite cromatography and eluted by 0.06 M sodium phosphate buffer, pH 6.8 is rich in adenine and thymine and contains about 2 times less 5-methylcytosine than the total wheat germ DNA. The degree of degradation of DNA on thermal denaturation is higher than on alkaline degradation. Therefore while studying reassociation of various DNA, one and the same standard method of DNA denaturation should be used. Besides, both the level of DNA degradation and the nature of the resulting products (fragments) should be taken into account.