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V L Iarovenko

Publications and source records attributed to V L Iarovenko.

8 recordsLinked to original sources
PubMed1977

[Spontaneous variability of Actinomyces werraensis].

The study of spontaneous variation of Act. werraensis not subjected to the treatment with mutagens and stabilizing selection revealed 6 variants within the homologous series of hereditary variation of apigmental actinomyces. The example of revealing the proactinomycete-like variants in Act. werraensis confirmed the prognosticating principle of the homologous series law in the hereditary variation of actinomycetes. Correlation between the cultural and morphological features of the spontaneous variants and the antibiotic-production level was shown. It was found that the variants of Act. werraensis had a high variation coefficient characteristic of the wild type actinomycetes. A possibility of increasing the biosynthetic activity of Act. werraensis by selection of spontaneous variants with artificial mutagenesis was shown.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Immobilization of commercial glucoamylase on the polymer carrier].

Commercial glucoamylase was immobilized on the polymer carrier produced by the binding of 4--8 mol.% 4,4'-diamine diphenyl oxide of the maleic anhydride copolymer with N-vinyl pyrrolidone. Two types of immobilized preparations were obtained: with covalent absorption and covalent attachment of the enzyme to the polymer. Glucoamylase activity of the first preparation was 20,000--60,000 and that of the second was 40--120 units/g polymer. Covalent-attached preparations showed a more prolonged action than covalent-absorbed ones.

Enzymes, Immobilized↗
PubMedDate not supplied

[Characteristics of transglucosilase from Aspergillus batatae].

Action of transglucosilase from Asp. batatae on different substrates is studied. The ratio of transglucosilase (upsilont) and hydrolase (upsilonh) activities on maltose under the action of transglucosilases from different origins is estimated. The degree of transglucosilating (upsilont/(upsilont+upsilon/)) increases with the increase of substrate molar concentration [S]. The ratio of transglucosilase and hydrolytic activities under the interaction of transglucosilase with half-products of starch metabolism is shown to depend on the concentration of glucose, the end product. The elimination of glucose from the incubation medium produces conditions for realization of hydrolytic pathway of the half-products conversion with transglucosilase. Schemes of the combined action of transglucosilase with alpha-amylase and glucoamylase under the starch conversion in enclosed and opened (continuous glucose elimination) systems are given.

Aspergillus↗
PubMedDate not supplied

[Separation and characteristics of the acid proteinases from a surface culture of Aspergillus terricola].

The enzymic preparation isolated by ethanol precipitation from the aqueous extract of the surface culture of Aspergillus terricola was purified on biogel P-10, fractionated on SE-Sephadex. As a result, 10 fractions of acid proteinases that differed in pH optima and activity were obtained. After purification specific activity of some fractions per 1 mg protein increased 24-32-fold. The temperature optimum of the enzymes was at 50 degrees C and pH optimum at 2.5--2.8.

Aspergillus↗
PubMedDate not supplied

[Some problems related to the regulation of the glucoamylase synthesis by Endomycopsis fibuligera 21].

The effect of different sources of carbon and other components on the glucoamylase synthesis by Endomycopsis fibuligera 21 was investigated. It was demonstrated that the enzyme was actively synthesized after the complete utilization of the carbon sources and the synthesis was not related to the presence of specific substrates in the medium. It was shown that water immersed washed cells of the producer accumulated high glucoamylase activity. It is suggested that the above yeast synthesize glucoamylase in the constitutive way and that the process may be regulated by catabolite repression.

Ascomycota↗