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V M Andrianova

Publications and source records attributed to V M Andrianova.

4 recordsLinked to original sources
PubMed1994

[The Petergof genetic collection of microorganisms].

The Petergof Genetic Collection (PGC) of microalgae was created in the 1960s during study of the regularities of mutational processes. A collection of yeasts has been maintained at the Department of Genetics and Selection of St. Petersburg State University since 1977. This collection contains some 1000 genetically marked strains of the yeasts Saccharomyces cerevisiae and Pichia methanolica, and the algae collection comprises about 600 strains of Chlamydomonas reinhardtii, Chlorella vulgaris, and Scenedesmus obliquus. The structure of the collection and the employment of strains in basic and applied research, as well as for educational purposes, are discussed. On the basis of the original software GENESTRAIN, a yeast PGC database (DB) was developed. A visual interface that contains information about selection of Ch. reinhardtii strains and crosses made was created in the HyperCard operational system.

Eukaryota↗
PubMed1983

[Genetic express-test for distinguishing between haploids and autodiploids in the yeast Saccharomyces].

Some originally haploid strains of yeast Peterhof breeding stocks obtained in tetrad analysis of diploids turned out to be spontaneous autodiploids after storage. They produced polyploid hybrids, as shown by tetrad analysis. An express-test for discrimination between haploids and autodiploids, based on the frequency of mitotic homozygotisation for a recessive marker has been developed. It is 10-100 times higher in heterozygous diploids than in duplex triploids. Tester strains bearing selective recessive lys2, sup1 or sup2 marker have been obtained. The hybrids of the tester strains and those to be tested were plated on media selective for mitotic segregants homozygous for lys2 (medium with alpha-aminoadipic acid and lysine) or sup1, sup2 (medium without adenine, while the hybrid was homozygous for ochre nonsense ade1-6 suppressible by either sup1 or sup2); UV-induced mitotic homozygotisation was scored. By our method, we have shown that spontaneous autodiploids constitute 70% of strains under investigation in Peterhof breeding stocks.

Cell Cycle↗
PubMed1978

[Regulation of purine nucleotide biosynthesis in mutant Saccharomyces cerevisiae yeasts with increased sensitivity of the pathway for de novo synthesis to inhibition by exogenous guanine].

Aza 165 and aza 238 Saccharomyces cerevisiae mutants characterized by a 2.5 times higher sensitivity of the de novo purine synthesis to the inhibitory effect of exogenous guanine, as compared with the wild type strain, have been selected by their sensitivity to 8-azaguanine. The exogenous guanine somewhat inhibits the growth and synthesis of nucleis acids in mutants, this being due in vivo neither to permeability changes of the cell membrane, nor to concentration changes of guanilic derivatives in the acid-soluble pool of yeast cells. Using cell-free extract of the strain aza 165, it has been shown that the synthesis of the first product of metabolic pathway for de novo formation of purines, phosphoribosylamine, is inhibited by GMP by 81% and only by 35% in the 15V-P4 strain of the wild type. The inhibition by other end products, IMP and AMP, is the same in both wild and mutant strains. The enhanced sensitivity of the purine synthesis to guanine in vivo is thus due to changes in regulatory properties of the key enzyme of purine nucleotide formation, phosphoribosylpyrophosphate amido-transferase (EC 2.4.2.14). This change in the regulation of purine synthesis in yeast is likely to be a mechanism to compensate the genetically controlled defect in end steps of the biosynthesis pathway, i.e. the incapability of converting guanilic derivatives to adenilic ones. However, the information concerning the regulation of PRPP-amido-transferase activity responsible for differential sensitivity to adenilic and guanilic nucleotides in yeast is not lost but only strongly repressed.

Adenosine Monophosphate↗