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Biomedical subjects

Iu B Filippovich

Publications and source records attributed to Iu B Filippovich.

At least 19 recordsLinked to original sources
PubMed1989

[Effect of the synthetic Leu enkephalin dalargin on the protein and nucleic acid content of the muscles in the rainbow trout].

After dalargin treatment of fish eggs (at the stage of swollen egg envelopes) and on juveniles (at the stage of early meiotic oocyte appearance in gonads) DNA content is observed to raise up to 85% and 66%, respectively in yearlings and up to 20% and 23% respectively in second-year fish as compared to the control ones. Dalargin also influences the exchange of muscle RNA in yearlings and second-year rainbow-trout. Dalargin effect is higher when peptide influences at the very onset of organism differentiation.

Animals↗
PubMed1984

[Regularities of the content and organization of pyrimidine oligonucleotide sequences in insect DNA].

Certain regularities in content and organization of pyrimidine oligonucleotide sequences of DNA from 15 insect species belonging to 4 orders were studied. The degree of nucleotide clusterization in insect DNA was found to be species-specific, being the highest in Hymenoptera and lowest in Lepidoptera; the Blattodea and Coleoptera occupy an intermediate position by this index between them. The changes in the DNA cluster structure during the evolution of insect species are not of vector type; the degree of clusterization of DNA nucleotide is either increased (Hymenoptera) or decreased (Lepidoptera as compared with Blattodea). In the DNA oligonucleotide fractions containing both pyrimidine nucleotides the percentage content of thymidyl nucleotides is much higher than that of cytidyl nucleotides, the thymine content being increased with the lengthening of oligopyrimidine clusters. The insect species with a higher degree of clusterization of DNA pyrimidine nucleotides contain more thymidyl nucleotide residues. These results agree well with the hypothesis suggesting that during the evolution of large taxons the accumulation of long pyrimidine sequences in animal DNA is accompanied by an increase of thymidyl nucleotide content in them. This can largely be due to the increase of matrix resistance during the evolution and is biologically significant for animals of any taxons, including insects.

Animals↗
PubMed1982

[Isolation and properties of carboxylesterase from hemolymph of the silkworm Bombyx mori L].

An original procedure for isolation and purification of carboxylesterase from the hemolymph of stage V larvae of one of Bombyx mori strains including precipitation with 10% polyethyleneglycol, ion-exchange chromatography on Sephadex G-200 and chromatography on DEAE-Sephadex A-50, has been developed. The specific activity of the enzyme after purification makes up to 1250 units per mg of protein with a 59% yield. Some physicochemical properties of the enzyme (Mr = 69 000, pI congruent to 4.9, temperature optimum = 40 degrees, pH optimum = 7.2 Km for alpha-naphthyl- and beta-naphthylacetate = 0.11 X 10(-3) and 0.52 X 10(-3) M, respectively) have been determined. Using immunodiffusion in agar gel, the antigenic identity of the enzymes isolated from the hemolymph of two silkworm species has been established.

Animals↗
PubMed1982

[Subcellular localization of some enzymes in silkworm eggs].

Differential centrifugation of the silkworm (Bombyx mori L.) egg homogenates resulted in nuclear, mitochondrial, lysosomal and cytosol infarctions, which were analyzed for the activities of alanine, aspartate- and tyrosine aminotransferases, 3-glycerophosphate- and lactate dehydrogenases and acid and alkaline DNAases. Alanine- and aspartate aminotransferases as well as 3-glycerophosphate dehydrogenase are localized mainly in the cytosol, where their activities made up to 86.2, 95.4 and 98.4% of their total activity, respectively. The activities of lactate dehydrogenase and acid DNAase are distributed between the nuclear and mitochondrial fractions; this distribution is even in the case of the former enzyme, whereas in the case of the latter the bulk (90.6%) of total enzyme activity is found in the nuclei. In contrast to the other enzymes whose activity is distributed between different cell fractions, tyrosine aminotransferase is localized exclusively in mitochondria, while alkaline DNAase--exclusively in the nuclei. No correlation between the level of enzyme specific activity and its total content in the fractions was established. The role of the enzymes under study in silkworm metabolism is discussed.

Animals↗
PubMed1982

[Isolation, purification and properties of acid deoxyribonuclease from silkworm Bombyx mori eggs].

The acid deoxyribonuclease was isolated from Bombyx mori eggs and its physico-chemical properties were investigated. The enzyme purified 160-fold did not contain admixtures of phosphomono- and phosphodiesterases or ribonuclease. The molecular weight of the enzyme is 40 000 +/- 1000, isoelectric point lies at 6.5. The maximum activity is revealed at pH 5.2, 50 degrees. The DNAase is insignificantly activated by Mg2+ and is inhibited by Cu2+ and Zn2+. The enzyme preferentially hydrolyzes native DNA and is an endonuclease splitting DNA down to 5'-oligonucleotides.

Animals↗
PubMed1982

[Separation and properties of multiple forms of acid phosphatase from the tissues and organs of the mulberry silkworm].

The multiple forms of acid phosphatase from the hemolymph, fat body, intestinal wall and silk gland of the silkworm larvae differing in their mobility during polyacrylamide gel electrophoresis were separated by isoelectrofocusing, gel filtration and ion-exchange chromatography and characterized in terms of their molecular weight, isoelectric points and substrate specificity. It was found that silkworm tissues contain several enzyme forms possessing broad substrate specificity (EC 3.1.3.2) as well as forms predominantly catalyzing the hydrolysis of glucose-1-phosphate (EC 3.1.3.10). The enzyme forms with a broad substrate specificity were detected in all tissues studied with the exception of hemolymph and were found to have the molecular weights above 60,000, pI greater than pH 6.0 and the highest activity within the pH range of 3.0-4.5. The enzyme forms causing predominant hydrolysis of glucose-1-phosphate detected in the hemolymph, fat body and intestinal wall are characterized by Mr = 30,000-100,000, pI below 6.0 and the highest activity within the pH range of 4.8-5.6. A possible role of the multiple forms of acid phosphatase in silkworm metabolism is discussed.

Acid Phosphatase↗
PubMed1980

[Metabolism of 14C-soluble proteins from silkworm tissues during silk formation].

The functional role of individual labelled fractions of haemolymph, fat body, carcass, gut and anterior and posterior divisions of the silk gland of the silkworm Bombyx mori was studied, using polyacrylamide gel electrophoresis. It was found that the protein fractions with Rf = 0.02, 0.05, 0.09 and 0.24 are formed in the gut, carcass and fat body during active feeding and are utilized by the silk gland in the spinning period by means of haemolymph. The contents of amino acids in several electrophoretic protein patterns (Rf = 0.02, 0.05, 0.09 and 0.24) in the haemolymph were determined. These protein fractions are sources of nitrogen-containing material used for increasing the level of free amino acids in the silk gland and for biosynthesis of major silk amino acids.

Adipose Tissue↗
PubMed1980

[Isolation, purification and properties of acid ribonuclease from the lysosomal fraction of silkworm eggs].

Acid ribonuclease (ribonucleate-3'-oligonucleotide hydrolase, EC 3.1.4.23) has been isolated from the lysosomal fraction of Bombyx mori eggs. The enzyme has a pH optimum of 4,7 and a molecular weight of 17 000 +/- 1000; the isoelectric point of the enzyme lies around 6,0. The enzyme splits RNA and poly(U) down to nucleoside-3'-phosphates to form intermediates--nucleoside-2',3'-cyclophosphates. Polyadenylic acid is hydrolyzed in the presence of the enzyme down to oligonucleotides. Mg2+ suppress the enzyme activity.

Animals↗